Justin Wang, MD
Resident Physician
Nassau University Medical Center
East Meadow, New York, United States
Jenzel Espares, DO
Resident Physician
Nassau University Medical Center
East Meadow, New York, United States
Chi Lam Kwok, DO
Resident Physician
Nassau University medical center
Rego park, New York, United States
Brent Fogel, DO
Resident Physician
Nassau University Medical Center
East Meadow, New York, United States
Forrest Butensky, DO
Resident Physician
Nassau University Medical Center
East Meadow, New York, United States
Ajendra S. Sohal, MD
Attending Physician
Nassau University Medical Center
East Meadow, New York, United States
Calcium pyrophosphate (CPP) is an insoluble salt produced by joint cartilage. Precipitation of CPP within joints is referred to as CPP deposition (CPPD). CPPD disease, also known as pseudogout, occurs when this deposition causes symptoms. CPPD can also be asymptomatic. CPPD disease can manifest as acute inflammatory arthritis, chronic inflammatory/degenerative arthropathies, and radiographic cartilage calcification. CPPD is estimated to affect 4-7% of adults in the Western world, and becomes increasingly common with advanced age. People with prior joint trauma are also at increased risk. CPPD disease most often affects the knee joint ( >50% of acute attacks) whereas traditional gout, caused by urate crystals, most often affects the first metatarsophalangeal joint. Diagnosis is by analysis of arthrocentesis fluid showing positively birefringent CPP crystals. Imaging can aid in the diagnosis by demonstrating chondrocalcinosis.
Conclusions: This case demonstrates a rare manifestation of pseudogout in which it affects a prosthetic joint. While post-implant pseudogout is rare, PJI is a serious complication of TKA that can lead to limb loss if not identified early. Due to the similarities in presentation, a prompt and comprehensive infectious work up, including arthrocentesis, followed by initiation of antibiotics is indicated.
