Hip Periprosthetic Joint Infection Due to in an Adult Male

is an obligate intracellular Gram-negative bacterium. "Query fever" (Q fever) first described in 1939 is a disease caused by . This bacterium infects animals including goats, sheep, and cattle, and has been recognized as a pathogen causing acute illness in humans. A patient living on a farm with a history of a right total hip arthroplasty presented with right hip pain. Arthrocentesis revealed a total nucleated count of 4288 (93% neutrophils), however his synovial fluid culture remained negative. His Q fever phase I IgG and phase II IgG were elevated at 1:4096 and 1:2048, respectively. He underwent incision and drainage with exchange of the femoral head and acetabular component, with retention of the femoral stem. PCR of tissue samples returned positive for . He was diagnosed with a persistent localized prosthetic joint infection (PJI) of the right hip. PJI is a rare but increasingly recognized form of persistent localized Q fever infection. Q fever should be considered in the differential diagnosis of culture-negative PJI, especially among patients with exposure to sheep, goats, or cattle. Initial screening for includes serology, but tissue PCR and immunohistochemical staining may be obtained to confirm joint infection