Heartworm Disease I- CardioRush

7-8 monthsHow long does it take after infection for microfilaria to be present in cats?Asymptomatic, pulmonary vascular disease, thrombus, Cor pulmonale/RCHF, eosinophilic pneumonitis, Caval syndrome, Glomerulonephropathy, DIC, Wolbacia infection, occult infection aberrant infectionWhat clinical syndromes may develop with HWD?Pulmonary vascular disease causes thrombus, secondary pulmonary hypertension and RCHFWhat occurs in Cor Pulmonale?TrueTrue or false: the majority of dogs are asymptomatic from HWD and we catch them by screeningClass I-IVWhat are the clinical stages of HWD?Class IWhat clinical stage of HWD is usually identified by routine screening, and clinical or imaging evidence of disease are usually absent of mild?Class IIWhat clinical stage of HWD is moderate disease with coughing and exercise intolerance but no CHF, and radiographic changes are present?Class IIIWhat clinical stage is severe HWD with cor pulmonale?Class IVWhat clinical stage of HWD is caval syndrome?False (it is primarily of the pulmonary arteries)True or false: HWD is a disease primarily of the heart3 weeksHow quickly after adult HW transplantation into the pulmonary arteries do vascular changes occur?Leukocyte and platelet activation, inflammationWhat is the result of endothelial damage from adult HWs in the pulmonary arteries?Villous endarteritisWhat histopathologic finding is virtually pathognomonic for HWD?Proliferation of smooth muscle in tunica media, migration of smooth muscle cells to intima and production of villiWhat occurs in villous endarteritis?Decreased lumen diameter, increased resistance, pulmonary hypertensionWhat is the result of smooth muscle hypertrophy from HWD in the pulmonary arteries?More severe pulmonary arterial diseaseWhat is the result of dogs exercising with an adult HW infection?3 months (with arrival of L5 in pulmonary vessels)At what point post infection can pathologic changes to the pulmonary arteries occur?Neutrophils, eosinophilsWhat cells contribute acutely to severe pulmonary arterial disease in HWD?Embolization, thrombosis, intense inflammation, pulmonary infarction, acute RCHF, resp failure, vascular ruptureWhat are some consequences of adult HW death?False (all consequences of adult death are the same in adulticide therapy)True or false: catastrophic consequences of adult HW death are only a threat if the adult worm dies naturally, not if adulticide therapy is used1-3 weeksWhen is the peak worm die-off expected after adulticide therapy?TrueTrue or false: PTE is a common sequelae to HWDPlatelet activation, endothelial damage, chronic inflammation, glomerulonephropathy, blood stasisWhat causes the hypercoagulable state that can lead to thrombus in HW infection, independent of adult worm death leading to embolism?TrueTrue or false: animals that were previously infected with HW will continue to have a coagulopathy once HWD has been resolvedLeft caudal (pulmonary vein largely distended on right)What lung lobe is most likely infarcted due to HWD?Chronic pulmonary disease, pulmonary hypertension, RV pressure overload, hypertrophy, RCHFWhat is the pathogenesis of cor pulmonale?Jugular and hepatic vein distention, ascites, pleural effusion, cachexiaWhat are the signs of RCHF that can manifest with cor pulmonale?Microfilaria sequestered in lungsWhat causes eosinophilic pneumonitis in HWD?Occult cannot detect microfilaria, patent canWhat is the difference in occult vs. patent HW infection?Microfilaria sequestered in lungsWhat causes occult HWD in dogs?Diffuse interstitial to alveolar patternWhat is the characteristic appearance of eosinophilic pneumonitis from HWD on chest radiographs?Granulomatous like reaction, can be mistaken for pulmonary neoplasiaWhat can eosinophilic infiltration in the lungs from HWD progress to?Interstitial to alveolar pattern consistent with pulmonary edema, which occurs in LCHF, but HWD affects the right heart which would cause pleural effusion, so this is actually eosinophilic pneumonitisThe following radiograph is taken of a heartworm positive dog that presents with dyspnea. Why is it not LCHF?Different treatmentsWhy is it important to differentiate eosinophilic pneumonitis from CHF?Caval syndromeWhat is the most severe presentation of HWD in cats and dogs?False (uncommon)True or false: Caval syndrome is commonRV, RA, vena cava, hepatic veinsWhere are the adult HWs located in caval syndrome?TrueTrue or false: caval syndrome is immediately life threateningAcute onset anorexia, weakness, collapse (cardiogenic shock)What are the signs of caval syndrome?Cor pulmonaleWhat is caval syndrome often complicated by?Shearing forces from worms in heartWhat causes hemolysis in caval syndrome?Hemoglobinemia, hemoglobinuria, anemiaWhat are the signs of hemolysis associated with caval syndrome?Immediate surgical removal of wormsWhat is the only treatment for caval syndrome?False (death of that many worms would immediately kill the animal)True or false: adulticide therapy is a good option in caval syndromeArrhythmias, increased central venous pressure, RCHFWhat are some possible consequences of caval syndrome that are more rare than hemolysis and low CO?Shorter than females, corkscrew headWhat are the characteristics of male HWs?Chronic antigenic stimulation, immune complexes with adult antigensWhat causes glomerulonephritis in HWD?Subacute membranous, diffuse focal plasma cell infiltrates in glomeruliWhat are the characteristics of glomerulonephritis from HWD?Proteinuria, hypoalbuminemia, loss of antithrombin, prerenal azotemia secondary to low COWhat are the signs of glomerulonephritis associated with HWD?False (it is potentially resolvable once adulticide occurs)True or false: glomerulonephritis as a result of HWD will remain once the adult worms are removedPrimarily from HWS or from adulticide treatmentWhat are 2 reasons DIC can occur in HWD?Endothelial damage, exposure of subendothelial collagen, platelet activationWhat causes DIC in severe HWD?Early hypercoagulation, later hypocoagulation as factors are consumedWhat are the two stages of DIC in HWD?False (may increase the host immune response)True or false: Symbiotic Wolbachia bacteria may decrease the host immune response to D. immitis infectionObligate intracellular gram negWhat are the characteristics of Wolbachia?Wolbachia surface protein, endotoxinWhat are the 2 toxin associated with Wolbachia?Development from L3 to L4, increase worm fecundityWhat are Wolbachia critical for in the filarial life cycle?Ivermectin, doxycyclineWhat can we treat HWD with to target Wolbachia in addition ot D. immitis to decrease pathology and improve outcome?TrueTrue or false: Pre-treatment with doxycycline and low dose ivermectin decreases pulmonary pathology associated with adulticide therapyLack of circulating microfilariaWhat characterizes immune mediated occult infections of HWD?Severe pulmonary vascular disease, eosinophilic pneumonitisWhat type of disease is more likely to occur in occult HWD?No microfilaria production, MF sequestered in lungsWhat are 2 reasons that HW infections may be occult?Microfilaria, neutrophils, eosinophilsWhat forms complexes in eosinophilic pneumonitis?Form giant cells, focal granulomasWhat is the result of complexes being phagocytosed by macrophages in eosinophilic pneumonitis?TrueTrue or false: the immune response in eosinophilic pneumonitis decreases fecundity of adult wormsIgG dependent leukocyte adhesionWhat type of adhesion in pulmonary vasculature occurs with microfilaria in eosinophilic penumonitis?Ectopic migration of larvaeWhat characterizes aberrant HW infections?Cats, peopleWhat animals are aberrant HW infections more likely to affect?Muscle, brain, spinal cord, anterior chamber of eyeWhat are some areas that HW larvae may migrate to in aberrant infection?Neuromuscular, ocularWhat are 2 common manifestations of aberrant HW infections?ATEWhat is the result of L5 migration into the arterial system in aberrant HW infections?TrueTrue or false: cats are resistant to HW infection compared to dogsPrevalence in dogsWhat does the prevalence of HWD in cats correlate geographically with?L5What stage of larvae tend not to survive in cats?False (immature worms can still result in clinical disease)True or false: because L5 larvae don't survive to adults, there is rarely clinical disease from HW in catsEctopic (brain, subQ, abdomen)What type of infections of HW are more common in cats than dogs?TrueTrue or false: Cats can get an intense respiratory distress that results form acute pulmonary injury, which may lead to pulmonary failureUsually very low worm burden, sometimes single sex infectionWhy are cats more likely to have occult HWD?1-3How many adult HWs tend to be present in cats?Dyspnea, cough, incidentalWhat are the most common presentations of feline HWD?Syncope, sudden death, CNS signs, emesisWhat are some uncommon presentations of feline HWD?Severe pneumonitisWhat can be caused by immature worms in cats with HWD?HW associated resp diseaseWhat is feline HARD?Feline asthmaWhat is HARD often confused with?Pulmonary insult from arrival of immature worms in pulmonary vasculatureWhat causes HARD in cats with HW?Radiographic changes, dyspnea, coughingWhat signs make HARD difficult to distinguish from feline asthma?False (hypertrophy of arterioles and inflammatory changes in small airways)True or false: feline HARD only affects the vasculature, not the lung parenchymaMedial hypertrophyWhat type of hypertrophy of the pulmonary artery is consistent with HARD?No, uncommonDoes Cor pulmonale and RCHF associated with chronic feline heartworm disease occur as frequently as in dogs?Smaller pulmonary arterial tree, less collateral circulation, embolization produces infarction or deathWhat are some differences in feline anatomy that make HWD more dangerous in cats?False (they are most commonly chronic but can be acute or peracute)True or false: onset of signs from feline HWD can be peracute or acute, but are rarely chronicTrueTrue or false: Dyspnea and cough are relatively consistent findings and when present, should cause suspicion of HWD in endemic areas