Recrudescence of Natural Coccidioidomycosis During Combination Antiretroviral Therapy in a Pigtail Macaque Experimentally Infected with Simian Immunodeficiency Virus.

Coccidioidomycosis is a common fungal infection in people living with HIV-1, particularly in southwest regions of the United States where the Coccidioides sp. is endemic, but rates of infection have significantly declined in the era of potent combination antiretroviral therapy (cART). Natural coccidioidomycosis also occurs in outdoor-housed macaques residing in the southwestern states that are utilized in biomedical research. Here, we report on a recrudescent case of previously treated, naturally occurring coccidioidomycosis in a pigtail macaque that was experimentally infected with simian immunodeficiency virus (SIV) and virally suppressed on cART. Coccidioides IgG antibody titer became detectable before discontinuation of cART, but symptomatic coccidioidomycosis developed subsequent to cART withdrawal. This animal was screened and treated in accordance with the guidelines for the prevention and treatment of coccidioidomycosis, suggesting that macaques with a history of coccidioidomycosis should be excluded from enrollment in HIV studies. Continual monitoring for known endemic pathogens based on the colony of origin is also recommended for animals utilized for HIV/AIDS research.