Heartworm Disease II- CardioRush

History, PE, serology, Knotts test, rads, echo, minimum database
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Terms in this set (72)
History, PE, serology, Knotts test, rads, echo, minimum database
What are the ways we diagnose and stage HWD?
Antigen test
What is the primary screening test for HWD in dogs?
Antibody test
What is the primary screening test for HWD in cats?
Inadequate prevention
What is the most important aspect of history in animals with HWD?
True
True or false: the majority of dogs that are diagnosed with HWD are caught by screening and are asymptomatic
Cough, dyspnea, exercise intolerance, syncope, collapse, abdominal distention, weight loss, lethargy, cachexia
What are some examples of possible clinical signs of HWD in a dog?
Loud or split S2, murmur from tricuspid regurg, S3 gallop, RCHF signs
Though the majority of dogs have no abnormalities on PE, what are some possible PE findings that may occur with HWD specific to the heart?
Pulmonary hypertension
What causes loud or split S2 in animals with HWD?
Pulmonary hypertension
What causes tricuspid regurgitation in animals with HWD?
Cough, inspiratory crackles, dyspnea, cyanosis, hemopysis
What are some respiratory PE findings that can be consistent with HWD?
Weight loss, cachexia, fever, petechia, ecchymosis, hemorrhage, icterus, hemoglobinuira, NM or ocular findingsWhat are some systemic PE findings consistent with HWD?Hemoptysis, feverWhat are the signs consistent with PTE in animals with HWD?DICWhat causes petechia, ecchymosis, and hemorrhage associated with HWD?Hemolysis from caval syndromeWhat causes icterus and hemoglobinuria associated with HWD?ELISA for protein released from adult female repro tractWhat does the HW antigen test specifically target?3 or more femalesHow many worms present usually cause the HW antigen test to be positive?Low worm burden, all males, prepatent infection, antigen bound to immune complexesWhat can cause a false negative on the HW antigen test?6-7 monthsWhat time after infection can an antigen test detect HWD?False (it is semiquantitative, repeat if the test is a weak positive)True or false: the HW antigen test is quantitativeHigh specificity, good sensitivityWhat is the sensitivity and specificity of the HW antigen test in a dog?7 months after peak exposureWhy should dogs be tested annually in the late spring for HWD?6 months (minimum)What age must a puppy be before using a HW antigen test?YesCan microfilaria be passed through the placenta?No (requires injection on L3 phase, microfilaria are L1)Can puppies get adult HWs from infection with microfilaria across the placenta?Immediately after, decays to 0 by 12 weeksWhen does the antigen level increase following adulticide or adult worm death?False (Don't need to test before 6 months, wouldn't give another adulticide treatment before then even if still positive)True or false: it is best to retest for HW antigen every week during adulticide treatmentTrueTrue or false: false positive antigen test is uncommon and is most likely a lab errorImmature worms (prepatent infection), single sex infection, low worm burdenWhat are the 3 most common reasons for false negative antigen tests for HWD?Low worm burdens make it much less sensitiveWhy is antigen testing for HWD not used for a screening test in cats?Confirmatory test after Ab screeningHow should antigen tests be used in cats to detect HWD?NoIs it necessary to heat treat every sample of serum before testing for HWD using the antigen test?Negative Ag but HW highly suspected, confirms resultWhat samples can heat treatment be used in?Use in monitoring effectiveness of slow kill treatmentWhy did heat treating samples before HWD antigen tests become popular?Antigen bound to Ig will be freed, more likely to be caught by ELISAWhat is the theory behind heat treating a serum sample before HW antigen testing?False (it is specifically for testing in cats)True or false: HW antibody testing can be used in dogsEarly as 2-3 months, usually by 5 monthsWhen following infection can an antibody HW test be positive in an infected cat?Higher sensitivity, lower specificityWhat is the sensitivity and specificity of the antibody test for HWD in cats compared to Ag test?Exposure, NOT active infectionWhat does a positive antibody test for HW in a cat indicate?Prepatent infection, live adult infection, persistent Ab following death of adult in previous infectionWhat 3 scenarios cause a positive antibody test for HWD in a cat?6 monthsHow long after worm or larval death with antibodies persist in a cat?90%What percentage of cats that are HWD infected will test positive on an antibody test?False (not a confirmation)True or false: Ab testing in cats is a confirmatory test for HWDAg test, echoWhat tests are needed to confirm HWD after a positive antibody test in cats?TrueTrue or false: ALL dogs that are positive by Ag test should also be tested for microfilaremiaModified Knotts test (concentration test that utilizes full mL of blood)What is the most sensitive test for microfilaria in the blood?Direct smear, microhematocrit testWhat are some other less sensitive tests than the modified Knotts that can be used to test for microfilaremia?False (always double check suspicious cases by looking for microfilaria)True or false: dogs with suspicious clinical findings that aren't positive on an antigen test usually don't need to be checked for microfilariaOccult infections prevalentWhy is finding microfilaria an insensitive method for diagnosing HWD?Occult infectionWhat is the term for active HW infection without circulating microfilaria (amicrofilaremia)?66%What percentage of cats with HWD have an occult infection?Iatrogenic, immune mediated, unisex infection, prepatent infectionWhat are some causes of an occult HW infection?Macrolide preventative kills microfilariaHow can an occult infection be iatrogenic?Unisex infectionWhat is a common reason for occult HWD infection in cats?IatrogenicWhat is the most common cause of occult HW infection?False (Also caused by Acanthocheilonema reconditum)True or false: only Dirofilaria immitis causes microfilaremiaTrueTrue or false: If a particular dog doesn't seem to make sense of having Dirofilaria but has microfilaria, then you should ask the lab to speciate the microfilariaCBC, chem, rads, macrolides therapy, adulticide theraapyIf a dog tests positive on an antigen test, but a modified Knotts test is negative, what should you do?Antigen testWhat should you do if a cat tests positive on an antibody test?CBC, rads, echo, microfilaria test, start preventativeWhat should you do if a cat tests positive on the antibody test but negative on the antigen test?Start preventative, baseline echo, treat symptomatically as neededWhat should you do for a cat that has a confirmed heartworm infection?CBC, Chem, urinalysis, UPCWhat is the minimum database that should be collected in HWD?Chem, tells most if healthy otherwiseIf you have to chose just one test from the minimum database to do before moving forward with treatment, which should you chose and why?Pulmonary diseaseWhat is the primary manifestation of HWD?False (they are an essential component of pretreatment eval, tells how severely they are affected)True or false: chest rads are ideal for establishing how affect an animal is in HWD, but not essential for treatmentRVWhat is the arrow pointing to?Enlarged MPAWhat is the arrow pointing to?PneumonitisWhat is circled?RV hypertrophyWhat does the shape of the heart mean on this view?Enlarged MPAWhat is the red arrow pointing to?Large PAWhat is the red arrow pointing to?Pulmonary hypertensionWhat does it mean if the pulmonary artery is larger than the vein?Eosinophilic pneumonitisA heartworm positive dog presents with coughing and radiographs are taken. What is the most likely finding?