barw Judi Clinical Journal 3105-4102 1 2 2025 11 24 Late-Onset Alkaptonuria in an Elderly Male: A Case Report and Literature Review 118 121 10.70955/JCJ.2025.14 eng Ronak S. Ahmed Scientific Affairs Department, Smart Health Tower, Madam Mitterrand Street, Sulaymaniyah, Iraq Shvan O. Siddiq Shahid Nabaz Dermatology Teaching Center for Treatment of Skin Diseases, Sulaimani Directorate of Health, Sulaymaniyah, Iraq Lawen J. Mustafa Rheumatology Department, Ministry of Health, Shorsh Street, Sulaymaniyah, Iraq Rawa M. Ali Hospital for Treatment of Victims of Chemical Weapons, Mawlawy Street, Halabja, Iraq Razan B. Jalal Scientific Affairs Department, Smart Health Tower, Madam Mitterrand Street, Sulaymaniyah, Iraq Omed M. Hussein Rheumatology Department, Ministry of Health, Shorsh Street, Sulaymaniyah, Iraq Saywan K. Asaad Department of Orthopaedics and Traumatology, Shorsh General Hospital, Sulaymaniyah, Iraq Abdullah K. Ghafour Scientific Affairs Department, Smart Health Tower, Madam Mitterrand Street, Sulaymaniyah, Iraq Lawand A. Sharif Department of Orthopaedics and Traumatology, Shorsh General Hospital, Sulaymaniyah, Iraq Sasan M. Ahmed Kscien Organization for Scientific Research (Middle East Office), Hamdi Street, Azadi Mall, Sulaymaniyah, Iraq 0009-0003-2842-9781 2025 08 21 Introduction: Alkaptonuria (AKU) is a rare autosomal recessive metabolic disorder caused by homogentisate 1,2-dioxygenase deficiency, leading to homogentisic acid accumulation. While AKU typically presents in children and young adults, this report aims to present an unusual late-onset presentation of AKU in an elderly male. Case presentation: A 65-year-old male presented with 20 years of black skin discoloration and chronic knee and pelvic pain. Despite early signs, including dark-colored urine, the condition was repeatedly misdiagnosed as melasma and primary osteoarthritis. Computed tomography scan revealed vertebral ankylosis and sacroiliac arthritis, and histopathological examination confirmed ochronotic pigment deposition. Due to financial constraints, the patient declined joint replacement surgery and was managed with diclofenac 100 mg twice daily and dietary restrictions. Literature review: Among six case reports of AKU reviewed in the literature, selected with a focus on misdiagnosis or delayed diagnosis, the majority of cases (3/6, 50%) occurred in the 8th–9th decades of life. Although AKU affects both sexes equally, five of the six reviewed cases (83.3%) were male. Conclusion: This case highlights the unusual late-onset alkaptonuria and the risk of prolonged misdiagnosis, emphasizing the importance of early recognition and multidisciplinary management.