Lab Studies:
Arthrocentesis obtained 160mL amber colored fluid which had 9,825 white blood cells predominantly lymphocytes and monocytes. Gram stain and culture were negative. Acid fast culture was negative. Urine gonorrhea and chlamydia tests were negative. C reactive protein, erythrocyte sedimentation rate, rheumatoid factor, Lyme antibodies were also negative.
Other Studies:
1. MRI of right knee showed large suprapatellar joint effusion containing frond-like fatty tissue consistent with lipoma arborescens Case Photo #1 . Regions of soft tissue enhancement along the synovium which may represent concurrent synovitis. Ligaments and meniscus were normal.
2. Arthroscopy showed multi-compartment synovitis which was resected and sent to pathology Case Photo #2 . Synovial tissue showed extensive lymphoblastic infiltrate necrosis and granulomatous inflammation with PAS and GMS stains positive for fungal spherules consistent with coccidioidomycosis.
Consultations:
1. Orthopedic surgery
2. Infectious disease
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