Rabies

Rabies – An Overview

A severe, invariably fatal, viral inflammation of the gray matter of the brain (known as “polioencephalitis”) of warm-blooded animals, including humans; “gray matter” is the nerve tissue of the brain that contains the nerve cell bodies.

Signalment/Description of Pet

Species

  • All warm-blooded mammals, including dogs, cats, and people.
  • United States—five strains of rabies virus are found in the skunk, raccoon, coyote, fox, and insectivorous bat populations; all five strains can be transmitted to dogs and cats.

Mean Age and Range

  • None, but adult animals that come in contact with wildlife are at most risk

Signs/Observed Changes in the Pet

  • Quite variable; atypical presentation is the rule rather than the exception
  • Three progressive stages of disease—(1) prodromal stage—early signs of disease; signs may include change in behavior, apprehension, nervousness, seeking solitude; (2) furious stage—signs may include irritability, excitability, avoidance of light (known as “photophobia”), and viciousness (biting, attacking); and (3) paralytic stage—also known as the “dumb form” of rabies; signs may include paralysis of various parts of the body (determined by location of original site of exposure to the rabies virus, such as a bite wound), change in voice (known as “dysphonia”), excessive salivation/drooling, and choking sounds; final signs include coma and death
  • 90% of cats with rabies have the furious form of disease
  • Change in attitude—pet seeks solitude; apprehension, nervousness, anxiety; unusual shyness or aggressiveness
  • Erratic behavior—biting or snapping; licking or chewing at site of wound; biting at cage; wandering and roaming; excitability; irritability; viciousness
  • Disorientation
  • Muscular incoordination; seizures; inability to move voluntarily (known as “paralysis”)
  • Change in tone of bark
  • Excess salivation or frothing
  • Paralysis of the lower jaw (mandible) and voice box or larynx; dropped jaw
  • Inability to swallow
  • Fever
  • Dilated pupils—unresponsive to light; unequal size of the pupils (known as “anisocoria”)

Causes

  • Rabies virus

Risk Factors

  • Exposure to wildlife, especially skunks, raccoons, bats, and foxes
  • Lack of adequate vaccination against rabies
  • Bite or scratch wounds from unvaccinated dogs, cats, or wildlife
  • Exposure to aerosols in bat caves
  • Pets that do not have the ability to develop a normal immune response (known as an “immunocompromised pet”)—use of modified live virus rabies vaccine

Treatment for Rabies

Healthcare

  • Strictly inpatient for pet suspected of being exposed to rabies or having rabies
  • Administer nursing care with extreme caution
  • No treatment for rabies
  • Once the diagnosis is certain, euthanasia is indicated

Activity

  • Confine to secured quarantine area with clearly posted signs indicating suspected rabies
  • Runs or cages should be locked; only designated people should have access
  • Feed and water without opening the cage or run door (in other words, pass food and water bowls into the cage or run through specialized access points designed for such use)

Diet

  • Soft, moist food; most affected pets will not eat

Surgery

  • Generally none
  • Skin biopsy—may help establish diagnosis before death of the pet; diagnosis must be confirmed by identification of rabies virus infection from central nervous system tissue

Follow-Up Care

Patient Monitoring

  • All suspected rabies patients should be isolated securely and monitored for any development of mood change, attitude change, or clinical signs that might suggest the diagnosis.
  • An apparently healthy dog or cat that bites or scratches a person should be monitored for a period of 10 days or according to local or state regulations; if no signs of illness occur in the pet within 10 days, the person has had no exposure to the virus; dogs and cats do not shed the virus for more than 3 days before development of clinical disease.
  • An unvaccinated dog or cat that is bitten or exposed to a known rabid animal must be quarantined for up to 6 months or according to local or state regulations.

Preventions and Avoidance

  • Vaccines (dogs and cats)—vaccinate according to standard recommendations and state and local requirements; all dogs and cats with any potential exposure to wildlife or other dogs and cats; vaccinate after 12 weeks of age; then 12 months later; then every 3 years using a vaccine approved for 3 years’ duration; use only inactivated virus or recombinant vector vaccines for cats.
  • Rabies-free countries—entering dogs and cats are quarantined for long periods, usually 6 months.
  • Disinfection—any contaminated area, cage/run, food dish, water bowl or instruments must be disinfected thoroughly; use a 1:32 dilution (4 ounces per gallon) of household bleach to inactivate the virus quickly.

Possible Complications

  • Paralysis
  • Attitude or behavior changes
  • Death
  • Exposure of rabies virus to other animals or people

Expected Course and Prognosis

  • Prognosis—grave; almost invariably fatal
  • Dogs and cats with clinical infection usually succumb within 1–10 days of onset of clinical signs; often within 3–4 days

Key Points

  • Rabies is a serious, usually fatal infection for the pet; rabies can be spread from animals to people (known as having “zoonotic potential”).
  • Tell your veterinarian about any possible human exposure (such as contact with the pet or other suspected rabid animal or a bite or scratch).
  • Any person possibly exposed to rabies should see a physician immediately.
  • Local public health officials must be notified.

Pemphigus

Pemphigus

BASICS-Overview

  • A group of diseases in which the immune system attacks the skin (known as “auto-immune dermatoses”); auto-immune diseases are ones in which the body produces antibodies against its own tissue; an “antibody” is a protein that is produced by the immune system in response to a specific antigen (a substance that induces an immune response)—when the body is exposed to the antigen (in the case of pemphigus, the antigen is some part of the skin), the antibody responds, resulting in signs of disease.
  • The pemphigus group of diseases is characterized by varying degrees of loss of tissue on the surface of the skin, frequently with inflammation (known as “ulceration”); dried discharge on the surface of a skin lesion (known as a “crust”); and formation of small, raised skin lesions containing pus (known as “pustules”) and blisters or small, circumscribed elevation of the outer layer of the skin filled with clear fluid (known as “vesicles”)
  • Affects the skin and sometimes the moist tissues of the body (known as “mucous membranes”)
  • Forms identified in animals include pemphigus foliaceous, pemphigus erythematosus, pemphigus vulgaris, panepidermal pustular pemphigus/vegetans, canine benign familial chronic pemphigus (Hailey-Hailey disease), and paraneoplastic pemphigus; type of pemphigus based on location of skin lesions and microscopic appearance of skin lesions

Genetics

  • Benign familial chronic pemphigus (Hailey-Hailey disease)—may be a genetic disease

Signalment/Description of Pet

Species

  • Pemphigus foliaceus, erythematosus, and vulgaris—dogs and cats
  • Panepidermal pustular pemphigus—dogs

Breed Predilections

  • Pemphigus foliaceus—Akitas, bearded collies, chow chows, dachshunds, Doberman pinschers, Finnish spitzes, Newfoundlands, and schipperkes
  • Pemphigus erythematosus—collies, German shepherd dogs, and Shetland sheepdogs

Signs/Observed Changes in the Pet

Pemphigus Foliaceus

  • Scales (accumulations of surface skin cells, such as seen in dandruff); crusts (dried discharge on the surface of skin lesions); pustules (raised skin lesions containing pus); superficial loss of skin tissue (known as “erosions”); reddened skin (known as “erythema”); hair loss (known as “alopecia”); circular patterns of hair loss (alopecia) bordered by scales or surface peeling of the skin (pattern is known as an “epidermal collarette”); and thickening of the skin (known as “hyperkeratosis”) of the footpads with furrows or slits (known as “fissures”)
  • Occasional blisters (vesicles) are transient
  • Common involvement—head, ears, and footpads; often becomes generalized
  • Lesions involving the moist tissues of the body (mucous membranes) and areas where the moist tissues of the body contact the skin, such as the lips (areas known as “mucocutaneous junctions”) are uncommon
  • Cats—nipple and nailbed involvement are common
  • Sometimes enlarged lymph nodes (known as “lymphadenopathy”), fluid buildup in the skin (known as “edema”), depression, fever, and lameness (if footpads involved) may be present; however, pets are often in good health
  • Variable pain and itchiness (known as “pruritus”)
  • Secondary bacterial infection is possible

Pemphigus Erythematosus

  • Same signs as for pemphigus foliaceus
  • Lesions usually confined to head, face, and footpads
  • Loss of pigment of the moist tissues (mucous membranes) and skin (known as “mucocutaneous depigmentation”) more common than with other forms of pemphigus; loss of pigment may precede crusting

Pemphigus Vulgaris

  • Pemphigus; loss of pigment may precede crusting
  • Ulcers of the mouth are frequent, and may precede skin lesions
  • Ulcerative lesions; superficial loss of skin tissue (erosions); circular patterns of hair loss (alopecia) bordered by scales or surface peeling of the skin (pattern is called epidermal collarettes), blisters, and crusts (dried discharge on the surface of skin lesions)
  • More severe than pemphigus foliaceus and pemphigus erythematosus
  • Affects moist tissues of the body (mucous membranes), areas where the moist tissues of the body contact the skin, such as the lips (mucocutaneous junctions), and skin; may become generalized
  • Area under the front legs and between the rear legs (known as the “axillae and groin”) often involved
  • Positive Nikolsky sign (new or extended erosive lesion created when lateral pressure is applied to the skin near an existing lesion)
  • Variable itchiness (pruritus) and pain
  • Lack of appetite (known as “anorexia”), depression, and fever
  • Secondary bacterial infections are common

Panepidermal Pustular Pemphigus

  • Pustule (raised skin lesion containing pus) groups become masses that ooze
  • Involvement of the mouth has not been seen
  • No systemic illness

Causes

  • Undetermined—genetics and a possible triggering event (such as a viral infection or medication)

Risk Factors

  • Undetermined

Treatment

Health Care

  • Initial inpatient supportive therapy for severely affected pets
  • Outpatient treatment with initial frequent hospital visits (every 1–3 weeks); taper to every 1–3 months when remission is achieved and the pet is on a maintenance medical regimen
  • Severely affected pets may require antibiotics and hydrotherapy/soaks

Diet

  • Low-fat—to avoid inflammation of the pancreas (known as “pancreatitis”), which can be a side effect of steroids and (possibly) azathioprine therapy

Surgery

  • Surgical biopsy of the skin lesion and the skin surrounding the lesions

Medications

Medications presented in this section are intended to provide general information about possible treatment. The treatment for a particular condition may evolve as medical advances are made; therefore, the medications should not be considered as all inclusive

Pemphigus Foliaceus and Pemphigus Vulgaris

  • Steroids—prednisone or prednisolone
  • Chemotherapeutic drugs and other drugs to decrease the immune response—more than half of pets require medications other than steroids to decrease the immune response; these drugs generally work in conjunction with prednisone, allowing reduction in dose and side effects of the steroid; examples include azathioprine, chlorambucil, cyclophosphamide, cyclosporine, and dapsone
  • Gold-salt treatment or chrysotherapy—gold salts are used to decrease inflammation and the immune response; often used in conjunction with prednisone; such as auranofin

Pemphigus Erythematosus and Panepidermal Pustular Pemphigus

  • Steroids—prednisone or prednisolone administered by mouth
  • Steroids administered by application directly to the skin (known as “topical steroids) may be sufficient in mild cases

Alternative Steroids

  • Use instead of prednisone, if undesirable side effects to prednisone or poor response occur
  • Methylprednisolone—for pets that tolerate prednisone poorly
  • Triamcinolone
  • Steroid pulse therapy—methylprednisolone sodium succinate administered intravenously for 3 consecutive days to induce remission; limited application

Topical Steroids (Administered to the Skin Directly)

  • Hydrocortisone cream
  • More potent topical steroids—0.1% betamethasone, fluocinolone, or 0.1% triamcinonide

Miscellaneous Medications

  • Tetracycline and niacinamide

Follow-Up Care

  • Monitor response to therapy

Monitor for medication side effects—routine bloodwork (complete blood count [CBC] and serum biochemistry), especially pets on high doses of steroids, chemotherapeutic drugs, or gold-salt treatment; check every 1–3 weeks, then every 1–3 months when in remission

Prevention and Avoidance

  • Pet should avoid the sun, because ultraviolet (UV) light may worsen the lesions

Possible Complications

  • Depend on type of pemphigus
  • Secondary infections
  • Side effects of medications may affect quality of life
  • Pemphigus foliaceus and pemphigus vulgaris may be fatal, if untreated (especially pemphigus vulgaris)

Expected Course and Prognosis

  • Treatment with steroids and chemotherapeutic drugs and medications to decrease the immune response is needed
  • Pets may require medication for life
  • Monitoring is necessary
  • Side effects of medications may affect quality of life
  • May be fatal, if untreated (especially pemphigus vulgaris)
  • Secondary infections cause morbidity and possible mortality (especially pemphigus vulgaris)

Pemphigus Erythematosus and Panepidermal Pustular Pemphigus

  • Relatively benign and self-limiting
  • Steroids administered by mouth eventually may be tapered to low maintenance doses; may be stopped in some pets (as directed by your pet’s veterinarian)
  • Skin disorder (known as “dermatosis”) develops, if untreated; generalized (systemic) signs are rare
  • Prognosis fair

Key Points

  • A group of diseases in which the immune system attacks the skin (known as “auto-immune dermatoses”)
  • Pet should avoid the sun, because ultraviolet (UV) light may worsen lesions

Lyme Disease

Lyme Disease – An Overview

  • One of the most common tick-transmitted diseases in the world.
  • Caused by spirochete species of the Borrelia burgdorferi group (such as B. burgdorferi, B. afzelii, B. garinii).
  • Dominant clinical feature (dogs)—recurrent lameness due to inflammation of the joints (known as “arthritis”); sometimes lack of appetite (known as “anorexia”) and depression; may develop kidney and rarely heart or nervous system disease.
  • Reported in people, dogs, horses, and occasionally in cats.
  • Also known as “Lyme borreliosis” or “borreliosis”.
  • Experimentally, young dogs (puppies) appear to be more susceptible to disease than do adult dogs

Genetics

  • Certain dog breeds (such as the Bernese mountain dog) are reported to develop severe kidney failure following infection with Borrelia.

Signs/Observed Changes in the Pet

  • Recurrent lameness due to inflammation of the joints (arthritis).
  • In studies, sudden (acute) form lasts for only 3–4 days; recurs days to weeks later in the same or in other legs (known as “shifting-leg lameness,” characterized by lameness in one leg, then that leg appears to be normal and another leg is involved); one or more joints may be swollen and warm; a pain response is elicited by feeling the joint; responds well to antibiotic treatment.
  • Affected dogs may refuse to walk or stand or may walk stiffly, with an arched back, and be sensitive to touch.
  • Long-term (chronic) inflammation of several joints, in which the bones around the joints are not destroyed (known as “non-erosive polyarthritis”) is found in pets with prolonged infection without adequate treatment; may persist despite antibiotic therapy.
  • Fever, lack of appetite (anorexia) and depression may accompany inflammation of the joints (arthritis).
  • Superficial lymph nodes close to the site of the infecting tick bite may be swollen.
  • Kidneys—reported glomerulonephritis with immune-complex deposition in the glomeruli leading to fatal kidney disease; “glomerulonephritis” is inflammation and accompanying dysfunction of glomeruli (plural of glomerulus) of the kidney; each kidney is composed of thousands of nephrons (the functional units of the kidney, each consisting of the glomerulus [a tuft of blood capillaries—the “blood filter”] and a series of tubes and ducts, through which the filtered fluid flows, as urine is produced); inflammation most commonly is due to the presence of immune complexes in the glomerulus.
  • Kidneys—loss of protein through the kidneys (condition known as “protein-losing nephropathy”) with resulting low levels of albumin (the type of protein lost through the kidneys) in the blood (condition known as “hypoalbuminemia”).
  • Kidney failure (signs include vomiting; diarrhea; lack of appetite [anorexia]; weight loss; increased urination [known as “polyuria”] and increased thirst [known as “polydipsia”]; fluid buildup in the tissues, especially the legs and under the skin [known as “peripheral edema”] or fluid buildup in the abdomen [known as “ascites”]).
  • Heart abnormalities—reported, but rare; include complete heart block.
  • Nervous system complications—rare.

Causes

  • Borrelia burgdorferi—transmitted by slow-feeding, hard-shelled tick species of the genus Ixodes (such as Ixodes scapularis [the deer tick], Ixodes pacificus, Ixodes ricinus, Ixodes persulcatus).
  • Infection—only after a tick (nymph or adult female) carrying Borrelia has been attached to the host for at least 18 hours.

Risk Factors

  • Roaming in tick-infested environment, where Lyme borreliosis is common (known as an “endemic area”)

Treatment for Lyme Disease

  • Outpatient
  • Keep pet warm and dry

Activity

  • Reduced activity advisable until clinical signs improve

Diet

  • No change needed

Surgery

  • Tapping the joint and removing joint fluid (known as “aspiration of synovial fluid”) may be considered for diagnostic purposes

Medications

Medications presented in this section are intended to provide general information about possible treatment. The treatment for a particular condition may evolve as medical advances are made; therefore, the medications should not be considered as all inclusive:

  • Most commonly used antibiotics—doxycycline, amoxicillin, or azithromycin.
  • Doxycycline—preferred in pets that have both Borrelia and Anaplasma phagocytophilum infections at the same time (Anaplasma is another tick-borne agent that causes disease).
  • Antibiotics do not eliminate the infection; consequently, persistent infection with a very low bacterial burden remains; treatment significantly improves clinical signs and disease.
  • Recommended treatment period—4 weeks.
  • Steroids—initially may cause signs to improve; may cover up or mask effects of antibiotics for diagnostic purposes; may increase clinical signs later by decreasing the ability of the pet to develop a normal immune response (known as “immunosuppression”).
  • Nonsteroidal pain medications—use judiciously to avoid covering up or masking signs; use only as directed by your pet’s veterinarian.

Follow-Up Care

Patient Monitoring

  • Improvement in sudden (acute) inflammation of the joints caused by Borrelia (known as “Lyme arthritis”) should be seen within 2–5 days of antibiotic treatment.
  • If no improvement within 2–5 days or is signs worsen, consider a different diagnosis.

Preventions and Avoidance

  • Mechanical removal of ticks—groom pets daily; discuss appropriate technique for removing ticks from your pet with the veterinarian.
  • Prevention of tick attachment—products to kill ticks (known as “acaricides”) and tick repellents are available commercially as spot-on topical products, sprays or collars; any such product should be used only according to label directions (do not use permethrin on cats).
  • Vaccines—are available commercially for dogs; talk to your pet’s veterinarian about the vaccine and vaccination protocols.
  • Tick population control in the environment—restricted to small areas; limited success by reducing deer and/or rodent population.

Possible Complications

  • Fatal kidney failure
  • Heart block
  • Central nervous system disorders

Expected Course and Prognosis

  • Recovery from sudden (acute) lameness expected 2–5 days after initiation of antibiotic treatment.
  • Disease may be recurrent with intervals of weeks to months; responds again to antibiotic treatment.

Key Points

  • Treatment of Lyme disease requires regular administration of antibiotics as prescribed by your pet’s veterinarian.
  • Prevent tick attachment—products to kill ticks (acaricides) and tick repellents are available commercially; any such product should be used only according to label directions (do not use permethrin on cats).
  • Diagnosis of Lyme disease (Lyme borreliosis) in a pet increases the risk to people living in the same area, as the people may be infected with Borreliaif they come into contact with ticks in the environment; they too should prevent tick attachment to themselves and should inform their personal physician of the pet’s diagnosis if they become ill.

Canine Leptospirosis

Leptospirosis – An Overview

  • “Leptospirosis” is caused by disease-causing members of the bacterial genus Leptospira.
  • Sudden (acute) and long-term (chronic) diseases of dogs (mainly inflammation of the kidney [known as “nephritis”] and inflammation of the liver [known as “hepatitis”]) and other animals, including cats, although rarely.
  • Dogs—serovars causing disease vary by geographic region, recent serovars of concern in the United States include Leptospira grippotyphosa,Leptospira autumnalis, and Leptospira pomona; “serovars” are subdivisions of a species that are different from other strains.
  • Dogs—ideally vaccines should include representative serovars found in the geographic region where the dog lives.
  • Young dogs—more likely to exhibit severe disease.
  • Old dogs with adequate protection from vaccinations—seldom exhibit clinical disease, unless exposed to a serovar not in the vaccine.

Signs/Observed Changes in the Pet

  • Vary with age and immune status of the pet, environmental factors that affect Leptospira survival, and disease-causing nature of the infecting serovar
  • May have no clinical signs.

Very Sudden (Peracute) Disease to Disease with Signs over a Moderate Amount of Time (Known as “Subacute Disease”)

  • Fever
  • Sore muscles
  • Stiffness
  • Shivering
  • Weakness
  • Lack of appetite (known as “anorexia”)
  • Depression
  • Vomiting
  • Rapid dehydration
  • Diarrhea—with or without blood
  • Yellowish discoloration to the gums and other tissues of the body (known as “jaundice” or “icterus”)
  • Spontaneous cough
  • Difficulty breathing (known as “dyspnea”)
  • Increased thirst (known as “polydipsia”) and increased urination (known as “polyuria”) progressing to production of no urine (known as “anuria”)
  • Bloody vaginal discharge
  • Death—without clinical signs

Very Sudden (Peracute) to Sudden (Acute) Disease

  • Rapid breathing (known as “tachypnea”)
  • Rapid, irregular pulse
  • Poor blood flow in the capillaries (smallest blood vessels; condition known as “poor capillary perfusion”)
  • Vomiting blood (known as “hematemesis”)
  • Passage of blood in the bowel movement or stool (known as “hematochezia”)
  • Black tarry stools, due to the presence of digested blood (known as “melena”)
  • Bleeding in the nose and nasal passages (known as “epistaxis” or a “nosebleed”)
  • Widespread small, pinpoint areas of bleeding (known as “petechia”); bruises or purplish patches under the skin, due to bleeding (known as “ecchymoses”)
  • Reluctance to move, overly sensitive to pain or touch (known as “hyperesthesia”) along the spine, stiff gait
  • Inflammation of the moist tissues of the eyes (known as “conjunctivitis”)
  • Inflammation of the nose (known as “rhinitis”)
  • Blood in the urine (known as “hematuria”)
  • Mildly enlarged lymph nodes (known as “lymphadenopathy”)

Long-Term (Chronic) Disease

  • May have no apparent illness
  • Fever of unknown origin
  • Increased thirst (polydipsia) and increased urination (polyuria)—long-term (chronic) kidney failure

Causes

  • Dogs—Leptospira canicola, Leptospira icterohaemorrhagiae, Leptospira pomona, Leptospira grippotyphosa, Leptospira copenhagenii, Leptospira australis, Leptospira autumnalis, Leptospira ballum, and Leptospira bataviae
  • Cats—Leptospira canicola, Leptospira grippotyphosa, Leptospira pomona, and Leptospira bataviae

Risk Factors

Transmission

  • Direct—host-to-host contact via infected urine, postabortion discharge, infected fetus/ discharge, and sexual contact (semen).
  • Indirect—exposure (via urine) to a contaminated environment (such as vegetation, soil, food, water, bedding) under conditions in whichLeptospira can survive.
  • Disease agent—Leptospira serovar, each with its own disease-causing factors, infectious dose, and route of exposure.
  • Leptospirosis in companion animals often is the result of spillover from disease occurring in wildlife (many different types of mammals) in the area; wildlife may act as “hosts” and maintain the different serovars.

Host Factors

  • Vaccine—protection is serovar-specific; prevents clinical disease as a result of specific serovar; may not prevent kidney colonization of Leptospiraand subsequent shedding of the bacteria in the urine; serovars not included in the vaccine may infect and cause disease in vaccinated pet.
  • Outdoor pets or hunting dogs—exposure of moist tissues of the body (mucous membranes) to water; exposure of abraded or water-softened skin increases risk of infection.

Environmental Factors

  • Warm and moist environment; wet season (high rainfall areas) of temperate regions; low-lying areas (marshy, muddy, irrigated); warm humid climates of tropical and subtropical regions.
  • Environmental temperature range—7–10 dg C (44.6–50 dg F) to 34–36 dg C (93–96 dg F).
  • Water—organism survives better in stagnant than in flowing water; neutral or slightly alkaline pH.
  • Organism survives 180 days in wet soil and longer in standing water.
  • Dense animal population—kennels and urban settings; increases chances of urine exposure.
  • Exposure to rodents and other wildlife.

Treatment

Health Care

  • Sudden (acute) severe disease—inpatient; extent of supportive therapy depends on severity of disease; kidney failure requires closely monitored, medically induced increased production of urine (known as “diuresis”).
  • Dehydration and shock—intravenous fluids (such as lactated Ringer’s solution).
  • Severe bleeding—blood transfusion may be needed in association with treatment for the blood-clotting disorder, known as “disseminated intravascular coagulopathy” or DIC.
  • Production of only small amounts of urine (known as “oliguria”) or no urine (known as “anuria”)—initially rehydrate; then give medications to increase production of urine (known as “diuretics”); peritoneal dialysis (a type of dialysis in which fluids are put into the abdomen and the lining of the abdomen [known as the “peritoneum”] acts as a filter to remove waste products from the blood; after a certain amount of time, the fluids and waste products are removed from the abdomen) may be necessary.

Activity

  • Suddenly (acutely) ill pets and pets with the presence of bacteria in their blood (known as “bacteremia”) or generalized disease caused by the spread of bacteria in the blood (known as “septicemia” or “blood poisoning”)—restricted activity; cage rest; monitoring; and warmth.

Diet

  • Severely ill pets—often have lack of appetite (anorexia); provide nutrition through intravenous feeding for prolonged anorexia.

Medications

Medications presented in this section are intended to provide general information about possible treatment. The treatment for a particular condition may evolve as medical advances are made; therefore, the medications should not be considered as all inclusive:

  • Procaine penicillin G—an antibiotic; administer until kidney function returns to normal
  • Dihydrostreptomycin—an antibiotic; administer for 2 weeks to eliminate organism from kidney tissues; try streptomycin if no kidney failure (drug not available everywhere)
  • Doxycycline—an antibiotic; administer for 2 weeks; use alone to clear Leptospira from the blood and urine
  • Ampicillin or amoxicillin—antibiotics; may be used instead of penicillin; administer for 2 weeks
  • Erythromycin—an antibiotic

Follow-Up Care

Patient Monitoring

  • Monitor bloodwork and urinalysis for kidney function and monitor bloodwork for liver function and electrolytes.
  • Monitor bloodwork (blood urea nitrogen [BUN] and serum creatinine) and urine specific gravity in dogs with kidney failure for indication of prognosis.

Preventions and Avoidance

  • Vaccine (dogs)—whole-cell bacterin vaccines contain the serovars Leptospira canicola and Leptospira icterohaemorrhagiae (some also now includeLeptospira pomona and Leptospira grippotyphosa); promotes immunity to these serovars and protection from overt clinical disease; serovar specific; does not promote protection against other serovars present in nature; may not prevent colonization of the kidneys of Leptospira, resulting in a long-term (chronic) carrier state; a “carrier state” is one in which the animal has no signs of disease, but harbors Leptospira and can transmit it to other animals.
  • Newer subunit vaccine contains the serovars Leptospira pomona, Leptospira icterohaemorrhagiae, Leptospira grippotyphosa, and Leptospira canicola; claims are made that the vaccine provides protection from clinical disease and prevents kidney colonization of Leptospira.
  • Vaccines—vaccinate dogs per current label recommendations; bacteria-induced immunity lasts only 6–8 months and is serovar specific (no cross-protection outside of the serogroup); revaccination at least yearly; vaccinate dogs at risk (such as dogs that hunt, show dogs, and dogs with access to water/ponds) every 4–6 months, especially in areas where Leptospira is found (known as “endemic areas”); the veterinarian will assess the risk of exposure and will recommend a vaccination protocol for your pet.
  • Kennels—strict sanitation to avoid contact with infected urine; control rodents; monitor and remove carrier dogs until treated; isolate affected dogs during treatment; “carrier dogs” are infected, but have no signs of disease—they harbor Leptospira and can transmit it to other animals.
  • Activity—limit access to marshy/muddy areas, ponds, low-lying areas with stagnant surface water, heavily irrigated pastures, and access to wildlife.

Possible Complications

  • Blood-clotting disorder (disseminated intravascular coagulopathy)
  • Liver and/or kidney dysfunction may be permanent
  • Inflammation of the iris and other areas in the front part of the eye (known as “uveitis”)
  • Abortion

Expected Course and Prognosis

  • Most infections are subclinical or long-term (chronic); a “subclinical infection” is one in which the animal is infected, but has no signs of disease.
  • Prognosis guarded for sudden (acute) severe disease.

Key Points

  • Leptospirosis has zoonotic potential from contaminated urine of affected dogs and their environment; “zoonotic diseases” can be passed from animals to people.

Canine Distemper

Canine Distemper – An Overview

  • Distemper is a contagious disease that appears suddenly (acute) or over a moderate amount of time (known as “subacute”), characterized by fever and a variety of signs involving the eyes, central nervous system, and respiratory, urogenital, and gastrointestinal tracts; often a fatal disease
  • Caused by the canine distemper virus
  • Affects many different species of the order Carnivora (dogs, fox, wolves, hyenas, weasels, ferrets, mink, raccoons, skunks and civets); mortality rate varies greatly among species
  • Young dogs, especially unvaccinated, dogs are more susceptible to infection than are adults

Signs of Distemper/Observed Changes in the Dog

  • Fever—first fever occurs 3–6 days after infection, may go undetected; second fever several days later (and intermittent thereafter), usually associated with discharge from the nose and eyes, depression, and lack of appetite (known as “anorexia”)
  • Gastrointestinal and/or respiratory signs follow, often enhanced by secondary bacterial infection.
  • Central nervous system signs—occur in many infected dogs; often, but not always, after generalized (systemic) disease; depends on the virus strain; either sudden (acute) gray or white matter disease (“gray matter” is the nerve tissue of the brain and spinal cord that contains the nerve cell bodies; “white matter” is the part of the brain and spinal cord that contains nerve fibers covered with myelin, a fatty covering that increases conduction of nerve impulses).
  • Gray-matter disease—affects the brain and spinal cord; may cause inflammation of the meninges (the membranes covering the brain and spinal cord; inflammation of the meninges known as “meningitis”), seizures, stupor, hysteria, and wobbly, uncoordinated or “drunken” appearing gait or movement (known as “ataxia”); dogs may die in 2–3 weeks; some dogs recover (associated with prompt immune response), while others progress to develop white-matter disease; “gray matter” is the nerve tissue of the brain and spinal cord that contains the nerve cell bodies; “white matter” is the part of the brain and spinal cord that contains nerve fibers covered with myelin, a fatty covering that increases conduction of nerve impulses.
  • White-matter disease—variable signs of disease involving multiple locations of the central nervous system; commonly see weakness and wobbly, uncoordinated or “drunken” appearing gait or movement (ataxia) secondary to spinal cord disease; occasionally may see twitching or contraction of a group of muscles (known as “myoclonus”); some dogs die 4–5 weeks after initial infection; some dogs may recover with minimal central nervous system injury.
  • Inflammation of the optic nerve (the nerve that runs from the back of the eye to the brain; condition known as “optic neuritis”) and lesions in the back of the eye (known as the “retina”) may occur.
  • Hardening of the footpads (known as “hyperkeratosis”) and nose—some virus strains; but relatively uncommon.
  • Abnormal development of the enamel layer of the teeth (known as “enamel hypoplasia”) after neonatal infection is common.

Risk Factors

  • Contact of animals that have not been vaccinated or have not responded to vaccinations with animals that are infected with canine distemper virus (dogs or wild carnivores)

Treatment for Distemper

  • Inpatient treatment in isolation, to prevent infection of other dogs
  • Supportive treatment, including intravenous fluids—cases with lack of appetite (anorexia) and diarrhea
  • Once fever and secondary bacterial infections are controlled, pets usually begin to eat again
  • Carefully clean away discharges from the nose and eyes

Activity

  • Limited

Diet

  • Depends on the extent of gastrointestinal involvement

Medications for Distemper

Medications presented in this section are intended to provide general information about possible treatment. The treatment for a particular condition may evolve as medical advances are made; therefore, the medications should not be considered as all inclusive:

  • Antiviral drugs—none known to be effective in treating canine distemper viral infections.
  • Antibiotics—to reduce secondary bacterial infection, because canine distemper virus decreases the ability of the dog to develop a normal immune response (known as “immunosuppression”).
  • Medication to control seizures (known as “anticonvulsant therapy”)—phenobarbital, potassium bromide.

Follow-Up Care

Patient Monitoring

  • Monitor for signs of pneumonia or dehydration from diarrhea in the sudden (acute) phase of the disease
  • Monitor for central nervous system signs, because seizures often follow

Preventions and Avoidance

  • Routine vaccination against canine distemper virus is key to prevention and avoidance; series of vaccinations administered initially followed by periodic booster vaccinations, as directed by your pet’s veterinarian
  • Avoid infection of puppies by isolation to prevent infection from wildlife (such as raccoons, fox, skunks) or from canine distemper virus-infected dogs

Possible Complications

  • Secondary bacterial infections, frequently involve the respiratory and gastrointestinal systems
  • Possibility of occurrence of central nervous system signs for 2–3 months after discharge from the eyes and nose has subsided
  • Seizures
  • Death

Expected Course and Prognosis

  • Depending on the strain of virus and the individual host response—dog may be infected, but have no signs of disease (known as a “subclinical infection”) or have signs of disease involving various areas of the body; the infection may be fatal or non-fatal.
  • Mild central nervous system signs—pet may recover; twitching or contraction of a group of muscles (myoclonus) may continue for several months or indefinitely.
  • Death—2 weeks–3 months after infection; mortality rate approximately 50%.
  • Euthanasia—owner may elect euthanasia, if or when nervous system signs develop; indicated when uncontrollable seizures occur.
  • Fully recovered dogs are not carriers, as they do not shed canine distemper virus.

Key Points

  • Mortality rate is about 50%
  • Dogs that appear to recover from early signs (such as discharge from the eyes and nose) may later develop fatal central nervous system signs
  • Fully recovered dogs are not carriers, as they do not shed canine distemper virus
  • Routine vaccination against canine distemper virus is key to prevention and avoidance; series of vaccinations administered initially followed by periodic booster vaccinations, as directed by your pet’s veterinarian

Bacterial Pneumonia

Bacterial Pneumonia – An Overview

  • Inflammation in the lung as a response to disease-causing bacteria, characterized by accumulation of inflammatory cells and fluid in the lung, conducting airways (bronchi and bronchioles), and alveoli (the terminal portion of the airways, in which oxygen and carbon dioxide are exchanged).
  • “Pneumonia” is inflammation of the lungs.
  • “Broncho” refers to the bronchi, the airways leading from the windpipe (known as the “trachea”) into the lungs.
  • “Upper respiratory tract” (also known as the “upper airways”) includes the nose, nasal passages, throat (pharynx), and windpipe (trachea).
  • “Lower respiratory tract” (also known as the “lower airways”) includes the bronchi, bronchioles, and alveoli (the terminal portion of the airways, in which oxygen and carbon dioxide are exchanged).
  • Inherited inflammation of the nose and inflammation of the smaller bronchi and lungs (known as rhinitis-bronchopneumonia complex”)—Irish wolfhound.
  • Dogs can get pneumonia, less common in cats

Breed Predilections

  • Dogs—sporting breeds, hounds, working breeds, and mixed-breed dogs (greater than 12 kg [26 lbs] of body weight)

Mean Age and Range

  • Dogs—common in young and old dogs; range, 1 month–15 years; many cases in puppies less than 1 year of age

Risk Factors

  • Contact of animals that have not been vaccinated or have not responded to vaccinations with animals that are infected with canine distemper virus (dogs or wild carnivores)

Signs/Observed Changes in the Pet

  • Cough
  • Fever
  • Labored breathing
  • Exercise intolerance
  • Lack of appetite (known as “anorexia”) and weight loss
  • Sluggishness (lethargy)
  • Nasal discharge
  • Difficult or rapid breathing
  • Abnormal breath sounds on listening to the lungs with a stethoscope (known as “auscultation”)—increased intensity or breath sounds over the bronchi; short, rough snapping sounds (known as “crackles”); and squeaking or whistling sounds (known as “wheezes”)
  • Dehydration

Causes

Dogs

  • Most common primary disease-causing organisms of the respiratory tract— Bordetella bronchiseptica and Mycoplasma.
  • Most common gram-positive bacteria—Staphylococcus, Streptococcus, and Enterococcus; gram staining is a technique in which slides with potential bacteria on them are stained in a sequential manner; gram-positive bacteria stain dark purple while gram-negative bacteria stain pink; gram staining allows differentiation of bacteria into groups (that is, gram-positive or gram-negative).
  • Most common gram-negative bacteria— Escherichia coli, Klebsiella, Pseudomonas, Pasteurella
  • Anaerobic bacteria (bacteria that can live and grow in the absence of oxygen)—found in lung abscesses and various types of pneumonia (particularly with aspiration or foreign bodies); approximately 20% of pets with bacterial pneumonia have anaerobic bacterial infections.

Cats

  • Bacteria—Bordetella bronchiseptica, Pasteurella, and Moraxella most frequently reported; Mycoplasma considered a primary disease-causing microorganism (known as a “pathogen”) in the lower respiratory tract.
  • Carrier state—may exist; periods of shedding Bordetella bronchiseptica after stress; infected female cats (queens) may not shed the organism during pregnancy (prepartum) but begin shedding it after delivering the kittens (postpartum), serving as a source of infection for kittens.

Risk Factors

  • Preexisting viral infection.
  • Regurgitation (return of food or other contents from the esophagus or stomach back up through the mouth), dysphagia (difficulty swallowing), or vomiting (forceful ejection of stomach contents up through the esophagus and mouth).
  • Functional or structural (anatomic) defects—paralysis of the voice box or larynx (known as “laryngeal paralysis”); enlarged esophagus (known as “megaesophagus”); cleft palate; inherited disorder in which the normal secretion clearance mechanism of the lungs is defective (known as “primary ciliary dyskinesia”).
  • Reduced level of consciousness—stupor, coma, or anesthesia.
  • Foreign body in the bronchi (part of the airway).
  • Long-term (chronic) dilation of bronchi or bronchioles, as a consequence of inflammation or blockage of the airway (known as “bronchiectasis”).
  • Drugs to decrease the immune response (known as “immunosuppressive drugs”)—such as chemotherapeutic drugs and steroids.
  • Severe metabolic disorders—excess levels of urea and other nitrogenous waste products in the blood (known as “uremia” or “azotemia”); sugar diabetes (diabetes mellitus); excessive production of steroids by the adrenal glands (known as “hyperadrenocorticism” or “Cushing’s syndrome”).
  • Presence of pus-forming bacteria and their poisons in the blood or tissues (known as “sepsis”).
  • Age—very young more susceptible to fatal infections.
  • Vaccination status.
  • Environment—housing, sanitation, ventilation.
  • Abnormal function of cells that normally remove bacteria and foreign materials from the body (known as “phagocyte dysfunction”)—feline leukemia virus (FeLV) infection and diabetes mellitus.
  • Complement (a protein substance in the blood that contributes to the destruction and removal of bacteria from the body) deficiency—rare.
  • Selective immunoglobulin A (IgA) deficiency; immunoglobulin A is an immune protein, found in the intestines; it functions as a protective barrier to prevent limit antigens (substance to which the immune system is responding and producing antibodies) and disease-causing microorganisms from entering the body through the intestines—rare.
  • Combined T-cell and B-cell dysfunction—rare; a lymphocyte is a type of white blood cell, formed in lymphatic tissue throughout the body; lymphocytes are further divided into T lymphocytes (which are involved in cell-mediated immunity), so-called “T-cells” and B lymphocytes (which produce antibodies as part of the immune process), so-called “B-cells”—rare.

Treatment

Health Care

  • Inpatient—recommended with signs involving multiple body systems (such as lack of appetite [anorexia], high fever, weight loss, and sluggishness [lethargy]).
  • Maintain normal hydration—important to aid the normal secretion clearance mechanism of the lungs; use a balanced electrolyte solution.
  • Administration of medication in a fine spray (known as “nebulization”) with saline aerosol—results in more rapid resolution, if used with physiotherapy and antibiotics.
  • Physiotherapy—efforts to dislodge secretions in the lungs and to induce coughing (known as “coupage”); windpipe manipulation to stimulate mild cough; and postural drainage; may enhance clearance of secretions; always do immediately after nebulization; avoid allowing the pet to lie in one position for a prolonged time.
  • Oxygen therapy—for pets with low levels of oxygen in their blood (known as “hypoxemia”) and signs of severe breathing difficulties (known as “respiratory distress”).

Activity

  • Restrict during treatment (inpatient or outpatient), except as part of physiotherapy after administration of medication in a fine spray (nebulization).

Diet

  • Ensure normal intake of food, with foods high in protein and calorie or energy density.
  • Feeding directly into the intestinal tract (known as “enteral feeding”) or through the veins (known as “parenteral nutrition”)—indicated in severely ill pets.
  • Use caution in feeding pets with an enlarged esophagus (megaesophagus); lack of normal function of the voice box or larynx (known as “laryngeal dysfunction”) or surgery on the voice box or larynx; disease of the throat or pharynx (known as “pharyngeal disease”), and pets that are unable to get up (they are recumbent).

Surgery

  • Surgical removal of a lung lobe (known as “lung lobectomy”)—may be indicated with lung abscesses or foreign body in the bronchus with secondary pneumonia; may be indicated if the pet is unresponsive to conventional treatment and disease is limited to one or two lobes of the lung(s).

Medications

Medications presented in this section are intended to provide general information about possible treatment. The treatment for a particular condition may evolve as medical advances are made; therefore, the medications should not be considered as all inclusive:

Antibiotics

  • Antibiotics are best selected based on results of bacterial culture and susceptibility testing from transtracheal wash (a technique in which samples from the lower airways are obtained for bacterial culture and/or for evaluation through a microscope) or other diagnostic techniques.
  • Reasonable initial antibiotic choices pending culture results include amoxicillin–clavulanic acid, cephalexin, enrofloxacin, or trimethoprim-sulfonamide.
  • Gram-positive cocci—ampicillin, ampicillin-sulbactam; amoxicillin; amoxicillin–clavulanic acid; azithromycin; chloramphenicol, erythromycin; gentamicin; trimethoprim-sulfonamide; first-generation cephalosporins.
  • Gram-negative rods—enrofloxacin; chloramphenicol; gentamicin; trimethoprim-sulfonamide; amikacin; marbofloxacin; carboxypenicillins.
  • Bordetella—doxycycline; chloramphenicol; enrofloxacin; azithromycin.
  • Mycoplasma—doxycycline, enrofloxacin, marbofloxacin, chloramphenicol.
  • Anaerobes (bacteria that can live and grow in the absence of oxygen)—amoxicillin–clavulanic acid; chloramphenicol; metronidazole; clindamycin; ticarcillin-clavulanic acid.
  • Administration of gentamicin in a fine spray (known as “gentamicin nebulization”) for Bordetella—typically used in conjunction with antibiotics given by mouth or injection.
  • Continue treatment for at least 10 days beyond clinical resolution and/or 1–2 weeks following resolution of x-ray (radiograph) evidence of pneumonia.

Antibiotics

  • Recommended by some veterinarians; no objective evidence that they increase movement of mucus or mobilization of secretions.

Bronchodilators

  • Recommended by some veterinarians; used to decrease spasm of the bronchi; bronchodilators are medications that enlarge the bronchi and bronchioles in the lungs.

Follow-Up Care

Patient Monitoring

  • Monitor breathing rate and effort.
  • Complete blood count (CBC) should be performed periodically; CBC should return to normal as the pet responds to treatment.
  • Arterial blood gases, to monitor levels of oxygen and carbon dioxide in the blood—most sensitive monitor of progress.
  • Monitor pulse oximetry; : “pulse oximetry” is a means of measuring oxygen levels in blood.
  • Listen to the pet’s lungs (auscultate) frequently.
  • Chest x-rays (radiographs)—improve more slowly than the clinical signs.

Preventions and Avoidance

  • Vaccination—against upper respiratory viruses; against Bordetella bronchiseptica, if dog is boarded or exposed to large number of other dogs.
  • Catteries—environmental strategies to lower the number of cats or the close proximity in which they are housed (known as “population density”) and improve hygiene help control outbreaks of bordetellosis (infection caused by Bordetella).

Possible Complications

  • Presence of pus-forming bacteria and their poisons in the blood or tissues (sepsis).

Expected Course and Prognosis

  • Prognosis—good with aggressive anti-bacterial and supportive therapy; more guarded in young pets, pets with decreased ability to develop a normal immune response (immunodeficiency), and pets that are debilitated or have severe underlying disease.
  • Prolonged infection—potential for long-term (chronic) inflammation of the bronchi (bronchitis) or chronic dilation of bronchi or bronchioles, as a consequence of inflammation or blockage of the airway (bronchiectasis) in any pet.
  • High death rates are associated with severely low levels of oxygen in the blood (hypoxemia) and presence of pus-forming bacteria and their poisons in the blood or tissues (sepsis).

Key Points

  • Inflammation in the lung as a response to disease-causing bacteria, characterized by accumulation of inflammatory cells and fluid in the lung, conducting airways (bronchi and bronchioles), and alveoli (the terminal portion of the airways, in which oxygen and carbon dioxide are exchanged).
  • More common in dogs than in cats.
  • Antibiotics are best selected based on results of bacterial culture and susceptibility testing.
  • High death rates are associated with severely low levels of oxygen in the blood (hypoxemia) and presence of pus-forming bacteria and their poisons in the blood or tissues (sepsis).