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Diagnostic Tests, Clinical Signs, and Treatment for Heartworms in Dogs, Cats, and Ferrets

Diagnostic Tests, Clinical Signs, and Treatment for Heartworms in Dogs, Cats, and Ferrets

Host

–-–----------------Diagnosis (Test Utility)---------------------

Clinical Signs

Prevention

------------Treatment------------

Microfilaria

Ag or Ab Test

Thoracic Radiographs

Echocardiography

Adults

Microfilariae

Dog

****

***** (Ag)

***

MPA, PA, RHE, PTE, PIE

**

Respiratory, weight loss, exercise intolerance, heart failure

Ivermectin, milbemycin, selamectin, moxidectin

Melarsomine, doxycycline, symptomatic treatment

Moxidectina, ivermectin + doxycycline, milbemycin

Cat

*

** (Ag)

**** (Ab)#

**

PA, PIE

****

Respiratory, vomiting, sudden death, heart failure

Ivermectin, milbemycin, selamectin, moxidectin

Symptomatic treatment;, doxycycline + ML, worm extraction

NA

Ferret

*

*** (Ag)

*

RH

***

Heart failure, respiratory, sudden death, heart failure

Topical imidacloprid-moxidectin product labeled for cats and ferrets

This product should be administered monthly at the recommended minimum dosage of imidacloprid (20 mg/kg), and moxidectin (2 mg/kg), by topical administration, regardless of indoor/outdoor status.

Symptomatic treatment (including corticosteroids) Possibly topical imidacloprid-moxidectin labeled for cats and ferrets

NA

aImidacloprid-moxidectin is the only approved microfilaricide.

* = rarely useful; ** = somewhat useful; *** = moderately useful; **** = often useful; ***** = excellent test; Ag = antigen; Ab = antibody; # = Ab-positive does not prove mature infection, only exposure/abbreviated infection; MPA = main pulmonary artery enlargement; PA = pulmonary artery enlargement; PTE = pulmonary thrombus/thromboembolus; PIE = pulmonary infiltrate with eosinophils; ML = macrocyclic lactone (macrolide); RH = right heart enlargement; NA = not applicable

Adapted from McCall, JW. Clin Tech Small Anim Pract. 1998;13(2):112.