Feline Flashcards
Feline Asthma
- there are no clinical signs or laboratory tests that are specific for feline asthma, it is primarily a diagnosis of exclusion, made by ruling out other causes of dyspnea, wheezing and coughing in an otherwise healthy cat
- Clinical signs of labored breathing, wheezing, cough
- Often acute onset at first presentation but may be chronic
- Radiographic bronchial pattern
- Treated with oral and/or inhaled steroids and bronchodilators
Pathophysiology of Feline Asthma
What does inflammatory infiltration cause? (3)
Airway reduction occurs from? (3)
why can CS’s be severe with mild airway constriction? (2)
There are many potential underlying causes and triggers of asthma that result in inflammatory cell infiltration into bronchial mucosa and submucosa. This causes:
a. Damage, hypertrophy and/or metaplasia of airway epithelium
b. Increased mucous production by goblet cells
c. Hypertrophy and spasm of bronchial smooth muscle
● Airflow reduction occurs from:
a. Airway edema
b. Airway narrowing from cellular infiltrates c. Airway smooth muscle constriction
● Dramatic clinical signs can be seen with relatively mild airway constriction because:
a. 50% reduction in diameter equals a 16-fold reduction in airflow
b. Stimulation of cough mechanoreceptors by inflammatory infiltrate
● Similarly therapeutic interventions allowing even small increases in airway size can yield dramatic benefits.
3 Presentations of Feline Asthma?
Comon signs? (4)
Differentials? (6)
Diagnostic Tests? (2)
3 presentations:
a. Cats with intermittent signs (i.e. signs occur less than daily)
b. Cats with consistent signs
c. Acute emergency presentation
● Common signs:
a. Cough
b. Dyspnea
c. Exercise intolerance
d. Wheezing
● Diagnosis of exclusion – major rule-outs are:
a. Heart disease
b. Pneumonia
c. Pneumothorax or pleural effusion
d. Pulmonary neoplasia
e. Inhaled foreign body
f. Respiratory parasites
● Diagnostic tests of choice
a. CBC
b. Thoracic radiographs
i. Classically see a bronchial pattern
ii. Characteristic “train tracks” and “doughnuts” which are thickened bronchial walls
Treatment of 3 Presentations for Feline Asthma?
Prognosis?
● Intermittent signs
a. Consider use of inhalant bronchodilator (albuterol) for use when symptoms occur.
b. Assumption is that chronic inflammation requiring daily anti-inflammatory therapy is not present.
● Consistent signs:
a. Treatment is long term corticosteroids
i. The most consistent and effective treatment is high-dose oral corticosteroids.
ii. Often start at 1-2 mg/kg PO BID for 10-14 days and taper.
iii. Once a response is seen, begin use of inhaled steroids as you taper from oral.
● Emergency presentation in acute respiratory distress:
a. Administer oxygen
b. Consider bronchodilator
c. Consider sedation
● Prognosis
a. For most cats with asthma, the disease is not curable but can be managed through appropriate therapy.
Feline Alveolar Lung Pattern
Pathophysiology (2)
- Fluid/Cells within alveoli
- collapse
will see radiographic fluid/soft tissue opacity
air bronchogram
- “trees in the fog”
- not always present
Differentials for feline alveolar lung pattern
Diseases
- Bronchopneumonia -tend to be more cranio-ventral
- Edema
- Cardiogenic vs. Non-cardiogenic - tend to be caudo-dorsally placed
- Atelectasis - collapse or closure of the lung
- Hemmorhage (less common)
- Mass (less common)
- Granulomatous (fungal)
- Neoplasia (histiocytic sarcoma- can sometime mimick the presence of other alveolar infiltrates such as bronchopneumonia)
- Torsion or infarction (relatively rare)
Location and Character - can guide you into what disease process that may be
“Mucus Plugging”
- a phenomena more often seen in feline asthmatic patients (tends to affect more often R middle lung lobe)
- might have notable atelectasis on Rx - more opacities in region of the lung field, change in position of the cardiac silhouette
- can also see with: pleural diseases (pleural effusion, pneumothorax)
“Lobar Sign”
- An alveolar pattern is the result of fluid (pus, edema, blood), or less commonly cells within the alveolar space.
- A total collapse of the alveoli (atelectasis) leads to a similar appearance. Radiographic signs include border effacement with other soft tissue structures such as the pulmonary vessels, cardiac silhouette or diaphragm.
- Smaller, ill-defined patches of alveolar pattern can coalesce into a more homogeneous soft tissue opacity where the only remaining gas is retained in the larger bronchi, seen as “air-bronchograms”.
- Air-bronchograms may not be visible early on in the disease process, their absence does not rule out alveolar disease.
- If the disease process does not spread to an adjacent lung lobe, the border of the affected lobe is sharply demarcated (“lobar sign”)
ptyalism
- hypersalivation
- may be indication of nausea in SA
Top Differential for mass lesion on the tongue of an older cat?
(may coincide with halitosis and ptyalism)
prognosis?
- Squamous Cell Carcinoma (SCC)
- Other differentials including eosinophilic granuloma complex, FIP granuloma, fungal granuloma, and bacterial granuloma are much less common
- Squamous cell carcinoma is a locally aggressive form of neoplasia that is associated with a poor prognosis unless it is caught very early (usually as an incidental finding). Median survival times for cats with this disease is about 2 months with only 10% still living 1 year after diagnosis
Ocular Dermoids in Cats
- Ocular dermoids in cats are usually characterized by the growth of hair on or near the cornea, or in the conjunctiva, the white of the eye.
- They may also appear on the upper eyelid. This condition is a rare congenital defect and will typically become apparent early on
Common Ocular Manifestations of herpesvirus in cats?
(2)
other possible findings?
- eosinophilic keratitis
- corneal sequestrum
- corneal ulcers - can be initiated by herpes virus
- conjunctivitis - also caused by herpesvirus - although can be caused by other things as well, such as calicivirus
Urticaria
- HIVES
- ed, itchy welts that result from a skin reaction.
- The welts vary in size and appear and fade repeatedly as the reaction runs its course.
- The condition is considered chronic hives if the welts appear for more than six weeks and recur frequently over months or years
What blood type are cornish rex, british short hair, and devon rex cats predisposed to?
- Type B blood type
- can lead to blood transfusion reactions marked by fever, restlessness, V+, urticaria, and hemoglobinuria
- Type B cats have anti A antibodies and tend to have acute transfusion reactions as compared with type A cats.
Indicated Treatment for Toxoplasma gondii Tx in cats?
What are CS’s possibly seen ?
- CLINDAMYCIN
- pyrexia, neurological signs (seizures), uveitis
- cats are a definitive host for this parasite
- often infected by eating raw food or infected prey
- an elevated IgM titer can show active infection with the organism
- The most common symptoms are lethargy, decreased appetite, and fever.
- The disease can cause diarrhea, upper respiratory symptoms, inflammation of the eyes, and neurologic disease
Tx for Indolent Ulcer in Cats?
- Immunosuppressive therapy and a change to a hypoallergenic diet
- an indolent ulcer is part of the eosinophilic granuloma complex - mainlyfound on the upper lip of cats
- These lesions can also extend into the oral cavity and can be found at the tongue base or hard palate.
- Typical treatment involves high doses of corticosteroids and identifying possible underlying allergic disease.
- Sometimes, antibiotics are indicated if severe infection is present. A hypoallergenic diet can be helpful if food allergy is the cause.
- Many times, the etiology is unknown but allergy is suspected
What can be effective hairball Tx?
- Frequent brushing, a higher quality diet, and a hairball treatment such as Laxatone (petroleum/mineral oil gel) should be recommended for this cat
- Metoclopramide is an anti-emetic and promotility agent and may be beneficial for hairballs if a high quality diet and laxatone fail to correct the problem.
Primary hyperparathyroidism
- most commonly caused by a parathyroid gland tumor
- commonly get CS’s: PU/PD, lethargy, nodule in thyroid gland region
- Cats will commonly not show significant clinical signs and may be diagnosed incidentally on routine blood work evaluation
- The elevated calcium causes the signs of PU/PD: The most common clinical sign of hypercalcemia is polyuria/polydipsia (PU/PD). This is a direct effect of hypercalcemia on the concentrating ability of the kidney
- Chronic hypophosphatemia usually is the result of decreased renal phosphate reabsorption
- elevated total and ionized Ca, lowered PO4-, hyposthenuria (lower USG0, Calcium oxalate crystals
- Sx is recommended
Hormones involved in Calcium and Phosphorus Regulation
(3)
- Vitamin D
- Parathyroid Hormone (PTH)
- Calcitonin
What would be an appropriate treatment in this case?
- Circummandibular cerclage wire placed caudal to canine teeth
- Separations of the mandibular symphysis are seen commonly with “high-rise syndrome” or when cats fall from heights because they frequently are able to rotate in mid-air, landing on all 4 feet to break the fall but often also landing with their lower jaw hitting the ground at the same time. This is sometimes referred to as a symphyseal fracture but it is not a true fracture as the mandibular symphysis never fully ossifies or fuses
- Symphyseal separation occurs with this type of trauma and right and left rami become distracted as is evident in the photo.
- The standard treatment is circummandibular cerclage wire placed caudal to the lower canine teeth with the wire tightened once the hemi-mandibles are aligned. A hypodermic needle is often used to guide placement of the wire
Wood’s lamp test
- In veterinary medicine, Wood’s lamps are most commonly used to help identify dermatophytosis caused by Microsporum canis
- Fungal culture is the most definitive diagnostic for dermatophytosis.
- Ketoconazole is not recommended in cats because it causes them to vomit.
- Examination of the lesions under a Wood’s lamp does not definitively rule out dermatophytosis; only about 50% of Microsporum canis organisms actually fluoresce under a Wood’s lamp. Other dermatophyte species do not fluoresce at all.
What is the most common cause of Cat Scratch Disease in humans?
Bartonella henselae
- Usually, you will see a papule at the site of inoculation followed by fever and local lymphadenopathy one week later.
- The lymphadenopathy will last months but is self-limiting. Neat! Cats are generally asymptomatic
IV dextrose
- can aid with hyperkalemia (as may happen with urinary obstruction in a cat)
- Dextrose. IV dextrose is helpful for longer term control of hyperkalemia.
- A 50% dextrose solution (1 mL/kg), diluted to a final concentration of 10% to 20%, is administered as an IV bolus.
- This treatment stimulates endogenous insulin release, causing intracellular translocation of plasma potassium - makes cells have an increased permeability to potassium
- be aware: in some cases, in the immediate post-obstructive period with urinary blockage, cats may develop hypocalcemic tetany - The mechanism is considered to be secondary to laws of mass action that drive down calcium as a result of existing hyperphosphatemia. Judicious use of calcium gluconate can quickly restore their electrolyte balance and prevent further complications such as hypocalcemic seizures
Where is the primary site of Cryptococcus infection in cats?
- In cats, dogs, koalas and psittacine birds, the nasal cavity is usually the primary site of infection.
- In cats, infections with feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) have been thought to predispose to cryptococcosis
Useful way of diagnosing feline cryptococcus infection?
- Serology
- The latex agglutination test against the cryptococcal antigen is very sensitive and specific and can be used to document disease or monitor therapy.
- It can be run on serum, CSF, or urine.
Lily Toxicity
- need to check BUN and creatinine levels immediately - NEPHROTOXIC!
- Lily plant toxicosis is extremely serious and can cause rapid and fatal acute renal failure in cats.
- If ingestion is suspected, decontamination and aggressive fluid therapy, and monitoring of renal values are recommended immediately
- Ingesting any part of the plant can cause complete kidney failure in 36-72 hours. may see anuria in 24-48 hours
- The toxicity may occur by ingestion of, or by mouthing, very small amounts of lily material.
acetaminophen toxicity in cats
- acetaminophen toxicity is death.
- Some cats will develop fluid buildup in the face, paws, and forelimbs several hours after ingesting acetaminophen.
- The urine may become dark or even chocolate-colored from the presence of blood or methemoglobin.
- Occasionally, the first sign of acetaminophen toxicity is death
- Heinz Body anemia may present
- Recall that cats are particularly sensitive to acetaminophen because they have decreased glucuronyl transferase activity which conjugates acetaminophen to glucuronic acid for excretion. As a result, 50-60 mg (a single tablet) may be fatal for a 4-5 kg cat
- Treatment should consist of toxin removal if possible by inducing emesis in some cases.
- The specific antidote is acetylcysteine which binds to some of the reactive metabolites of acetaminophen and increases the availability and synthesis of glutathione.
- Other treatments may include S-Adenosylmethionine (SAMe) which has hepatoprotective and antioxidant properties. Cimetidine can be given to inhibit the p450 oxidase in the liver and limit formation of toxic metabolites.
- Ascorbic acid can also be used as an adjunct treatment to bind toxic metabolites.
- In cats with signs of hypoxemia from severe hemolytic anemia (PCV <20%), a transfusion and further supportive care may be warranted.
When performing a subtotal colectomy on a feline patient, what blood vessel limits the amount of colon that you are able to remove?
- Ileocolic artery
- The ileocolic artery provides blood supply to the ascending and transverse colon.
- The site for colonic resection is limited by tension on the ileocolic artery when trying to suture your new end of colon to the rectum.
- Sometimes the tension is too great and instead of a colocolic anastomosis, an ileocolic anastomosis must be performed.
- Essentially you are trying to connect a section of ascending colon to the rectum. Now that can be pretty far! Performing an ileocolic anastomosis is not ideal because you eliminate the ileocecal valve, and that may predispose the animal to bacterial overgrowth
How does DM cause PU/PD?
- The increased glucose in the blood overwhelms the kidneys, which can no longer filter out all the glucose, and some spills into the urine.
- The glucose in the urine draws water in from the body, causing an increased volume of urine (polyuria).
- To avoid becoming dehydrated, the pet consumes more water (polydipsia).
Skin Fragility Syndrome
- Typically, these patients appear to have a normal looking coat from a distance but when palpated or manipulated one must be very careful, particularly when scruffing the patient
- Skin fragility syndrome in cats is commonly associated with poorly regulated diabetes mellitus due to hyperadrenocorticism
- Cushing’s disease can cause insulin resistance. Clinical signs are similar to those seen in dogs (pendulous abdomen, polyuria, polydipsia, polyphagia, lethargy, and muscle wasting).
- The hyperadrenocorticism can be iatrogenic, adrenal dependent or pituitary dependent.
- In cats, approximately 80% have a pituitary tumor while 20% have an adrenal tumor.
- ACTH stimulation test is not recommended in cats due to poor sensitivity. The low dose dexamethasone suppression test is recommended to confirm hyperadrenocorticism. Urine cortisol-creatinine ratio can be used as a screening tool. The UCCR has a high sensitivity so a negative test makes Cushing’s highly unlikely.
- Abdominal ultrasound can be used to support your diagnosis. With pituitary dependent Cushing’s (which constitutes 80% of cats), you would expect normal to hypertrophied/enlarged adrenal glands.
- The excessive ACTH secreted from the pituitary gland produces an excessive amount of cortisol and adrenal hypertrophy
What is true concerning migration and feline heartworm disease?
- Migration of larvae to ectopic regions (outside of the heart and pulmonary arteries) is same or more common than in dogs
- Cats do typically have fewer adult worms than dogs because of increased natural resistance.
- Cats are often microfilaria negative despite an active infection (either from all male worm infections, or occult disease).
- Antibody testing can detect exposure to both male and female worms; however, in cats, larvae are more likely to migrate to ectopic locations such as the brain, skin, and ocular tissue.
Life Cycle of Toxoplasma gondii
The most common symptoms are lethargy, decreased appetite, and fever.
The disease can cause diarrhea, upper respiratory symptoms, inflammation of the eyes, and neurologic disease.
The treatment for this infection is the antibiotic Clindamycin (lincomycin AB)
What differentials can explain the presentation shown here?
- cat is exhibiting cervical ventroflexion
- most common: hypokalemia, often due to chronic renal failure
- others: myasthenia gravis; polymyopathies caused by toxoplasmosis, immune-mediated disease, or hyperadrenocorticism; and neuropathies caused by organophosphate poisoning, thiamine deficiency, or botulism.
Infection by FHV-1
(primary infection v. recurrence)
- parturition can be a stressful time and the mother may experience recurrence while birthing and pass it to the kittens (whom will develop a primary infection)
- 29% of cats will have an identifiable STRESSOR at the time of recrudenscence
Common Sequelae to FHV-1 (5)
- dry eye is quite rare in cats and is more thought to be due to chronic irritation casing closure of the lacrimal ductules rather than issues with the lacrimal gland
What is the most common systemic mycosis of cats?
systems often involved?
Tx options?
- cryptococcosis
- breed predispositions: siamese, birman, ragdolls
- systems affected: upper respiratory, cutaneous, and CNS signs
- more prevalent in Western United States
- source: often identified as bird waste (pigeon), decaying plant matter, hollows of certain trees
- nasal cavity often seems to be the initial site of infection
- Treatment: Azoles (Fluconazole - most effective for cats with CNS involvement, Itraconazole, Ketoconazole), Amphotericin B - should also treat with, but carefully (given parenterally, nephrotoxic), Flucytosine - should not be used alone - monotherapy can lead to resistance, Sx
What should Dietary therapy for CKD entail?
(5)
What type of hypersensitivities can result from FAD? (flea allergy dermatitis)
Where does it often present in cats?
Type 1 and 4, and basophil hypersensitivities.
Salivary enzymes contain proteolytic enzymes, histamine-like compounds, anti-coagulants, haptens and antigens.
Often presents on: neck and face (but also see posterior like dogs)
Intradermal Testing for FAD?
(sensitivity/specificity)
Why does it usually take 2-3 months to eliminate fleas from pets/home?
Insect growth regulators
Rivalta’s Test
- Rivalta’s test has the highest negative predictive value in the diagnosis of FIP. This means that a negative test is likely associated with the cat truly not having the disease
- False positives are more commonly seen in older cats and cats with lymphoma or bacterial infections but negative results are relatively convincing compared to most other diagnostic tests for this disease
- Immunofluorescence staining for coronavirus in macrophages in effusion fluid has been reported to have a PPV= 100% and NPV= 57% in comparison
2 most common species of cryptococcus infecting cats?
- C. neoformans
- C. gattii
found in bird excreta (exp. pigeons), decaying plant matter, hollows of certain trees
in cats - nasal cavity seems to be the initial site of infection
- get URT signs
- ulcerative lesions or nodules on skin
- can then spread hematogenously via macrophages to a number of different tissues: Lungs, CNS, LN’s, eyes
- may also get LUT signs, PU/PD if renal system is involved
even a titre of 1-2 on a serology test is considered significant - can often isolate organisms alone or pyogranulomatous lesions
The Cryptococcal Antigen Latex Agglutination System (CALAS) test has a high sensitivity and specificity
Tx: Azoles (fluconazole, itraconazole, amphotericin B, Sx)
- fluconazole is the most effective treatment for cats with CNS involvement, but they should also be treated with amphotericin B which breaks up fungal cell membranes
- Capillaria aerophila eggs
- can perform a routine fecal flotation and see double operculated eggs with asymmetric terminal plugs
- Capillaria ova look similar to Trichuris eggs but are smaller and have asymmetric terminal plugs. Most cases of Capillaria are asymptomatic but chronic cough may be seen.
Cytauxzoon felis
- Transmitted by fleas, Dermacentor variabilis or Amblyomma americanum are the most likely vectors.
- The disease in cats is rapidly progressive and almost 100% fatal.
- A recent study shows 32 of 34 cats dying or being euthanized as a result of infection.
- Clinical signs include anorexia, lethargy, dyspnea, dark urine, dehydration, icterus, fever, prolonged capillary refill time, and death (essentially disseminated intravascular coagulation).
- Ring-shaped organisms can be seen in erythrocytes or schizonts in spleen, liver, blood, bone marrow aspirates, or lymph nodes
What are the first mandibular premolars in cats numbered as?
What lesion is prone to occur here?
- 307 and 407
- feline odontoclastic resorptive lesions can occur in any tooth, they are most frequently found in the first premolars, 307 and 407 in feline patients.
- So far, there is still no explanation for why these teeth are more vulnerable to this process
Feline Acne
- Feline acne is a common condition of cats; it is a deep pyoderma condition of the chin.
- Treatment involves cleaning the site with antiseptic solutions.
- You should rule out other conditions such as mite infections or dermatophytosis
- Cat acne occurs due to excessive keratin production at the hair follicles (follicular keratinization) and over-secretion from sebaceous glands.
- This leads to blockage of the hair follicles with a combination of keratin and sebum, the oily secretions from the skin glands.
- In cats, acne is thought to be most common around the chin area, which is why it’s commonly referred to as cat chin acne
Budesonide
- Corticosteroids such as prednisolone and budesonide are the most common medications used for controlling inflammatory bowel disease in cats.
- Budesonide concentrates its effects in the gastrointestinal tract, thus has fewer systemic side effects as compared to prednisolone.
- Sulfasalazine and metronidazole can be used to help the condition by treating secondary bacterial overgrowth.
- Other treatments include an easily digestible diet and one with a novel protein source, pro-motility agents or anti-nausea agents such as metoclopramide when needed, and vitamins such as cyanocobalamin (vitamin B-12) or omega-3 fatty acids may also be of benefit in some cases.
Notoedres cati
- Notoedric mange, also referred to as Feline scabies, is a highly contagious skin infestation caused by an ectoparasitic and skin burrowing mite Notoedres cati.
- N. cati is primarily a parasite of felids, but it can also infest rodents, lagomorphs, and occasionally also dogs and foxes
Cat breeds with Type B blood
Common B blood type breeds include:
British Shorthairs, Devon and Cornish Rex, Ragdolls, Scottish Fold, Persians, and Himalayans.
Symblepharon
- A symblepharon is a partial or complete adhesion of the palpebral conjunctiva of the eyelid to the bulbar conjunctiva of the eyeball. It results either from disease (conjunctival sequelae of trachoma) or trauma.
- can see with feline herpes virus
- Symblepharon is adhesion of part of the conjunctiva onto the cornea/limbus in cats with herpes induced epithelial erosions.
- Dendritic ulcers (superficial branching ulcers seen with Rose-bengal staining) are pathognomonic for herpes.
