Thread by @IUIDfellowship

#idboardreview 50 M s/p heart transplant 5 yrs ago, has outdoor cats, presents w/ fever, thigh nodule, groin lymphadenopathy. diagnosis? #medEd #idmeded #idtwitter

#Bartonella henselae gram neg bacilli. Human infection is typically associated with cat and flea exposure, particularly young cats. Immunocompetent: typically localized, self-limited lymphadenitis near site of inoculum, cat scratch disease

#bartonella Immunosuppressed pts: risk for dissemination. Solid organ transplantation: increased frequency of cases in renal transplant recipients, followed by liver, then lung and heart transplant recipients

#bartonella time from transplant-infection: 1mo-14 yrs. Often disseminated earlier in post-transplant course, while those with localized cat scratch disease typically present later. Most cases w/ cat exposure reported cases from transplant and reactivation from immunosuppression

#bartonella Solid organ transplant recipients with disseminated bartonellosis often present w/ non-specific fever, night sweats, headache, some w/ hepatomegaly and splenomegaly. Dx serology, PCR, culture, and histopathology.

#bartonella serology or culture can be neg earlier as fastidious, slow-growing. Pathology +granulomas +Warthin-Starry silver stain

#bartonella if localized immunocompetent: no tx. When needs tx: doc azithromycin. Immunosuppressed either monotherapy or azithro+doxy. Consider reduction in immunosuppression. Duration few wks-several months based on degree of dissemination & clinical response.