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Published on: February 14, 2011
Acute Anaplasma phagocytophilum infection in a pediatric domestic cat
Molly Graham1, Patty Ewing1, Megan Whelan1
1Angell Animal Medical Center, Boston, MA, USA.
Case Summary:
A domestic shorthair cat estimated to be 4-6 weeks old was presented to a referral center for evaluation of lethargy, anorexia and diarrhea for a duration of 24 h. A feline vector-borne PCR panel, as well as a blood smear, examined by a board-certified pathologist, confirmed an Anaplasma phagocytophilum infection. Morulae were identified in both feline neutrophils and eosinophils. Treatment consisted of a 21-day course of liquid doxycycline. Clinical signs rapidly resolved and were not noted to recur.
Relevance And Novel Information:
This case demonstrates that A phagocytophilum can infect cats as young as 4-6 weeks old. Doxycycline, as the antibiotic of choice for the treatment of A phagocytophilum infections, was used. Consistent with the literature, a rapid clinical improvement was detected. Anaplasmosis should be listed as a differential diagnosis in pediatric cats suffering from acute febrile illness with potential previous tick exposure (history of living outdoors) in order to provide proper treatment.
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