eng Science and Education Publishing American Journal of Medical Case Reports 2374-216X 2025-06-13 13 4 22 25 10.12691/ajmcr-13-4-1 AJMCR20251341 article Najlaa Al-Sudani Najlaa.alSudani@memorialhermann.org 1 Department of Internal medicine, Memorial Hermann Health System, Houston, Texas, USA Gout and septic arthritis share similar clinical characteristics, including acute joint pain, swelling, fever, and increased inflammatory markers, which make the diagnosis and differentiation more complicated. This challenge is further exacerbated in patients with chronic kidney disease (CKD), who are at risk for both crystal arthropathy and infections. We present a 73-year-old male with CKD stage 3 who initially presented with monoarthritis and systemic symptoms suggestive of septic arthritis; however, synovial fluid analysis showed monosodium urate crystals and sterile cultures. His history of recurrent gout supported the final diagnosis. Following corticosteroid treatment, the patient had rapid improvement in symptoms. This case highlights the diagnostic difficulties and the essential role of synovial fluid analysis in differentiating gout from septic arthritis in CKD patients, stressing the need for a high index of suspicion and tailored management. https://pubs.sciepub.com/ajmcr/13/4/1/ajmcr-13-4-1.pdf Acute gout Chronic kidney disease Diagnostic challenge Differential diagnosis Gout mimicking infection Monoarthritis Septic arthritis Synovial fluid analysis