Erdheim-Chester disease: An elusive diagnosis in a 50-year-old Ethiopian man presenting with diffuse sclerotic bone lesion.

Key Clinical Message: Diagnosis of Erdheim-Chester disease (ECD) requires the clinician to be familiar with its various manifestations, classic radiologic and histologic features. This case highlights the significance of considering ECD in any patient presenting with bone pain and symmetric osteosclerosis of long bones of extremities to allow for early diagnosis and treatment. Abstract: Erdheim-Chester disease (ECD) is a rare non-Langerhans histiocytic disorder with diverse clinical manifestations, ranging from indolent, localized presentation to life-threatening, multi-systemic disease. Delayed or erroneous diagnosis is common. The presence of classic radiographic finding along with foamy histiocytes that is positive for CD68 but negative for CD1a on histologic examination establishes the diagnosis. We report a second case of ECD from Ethiopia. A 50-year-old Ethiopian man presented with a 13-year history of bilateral lower leg bone pain, cold intolerance, somnolence, constipation, impotence, decreased libido, and secondary infertility. The diagnosis was suspected when skeletal X-ray revealed bilateral symmetric sclerosis of metadiaphysis of femur, tibia, and humerus. The demonstration of foamy histiocytes that were positive for CD68 but negative for CD1a on histologic examination with immunohistochemical staining confirmed the diagnosis. Evaluation for the extent of the disease revealed coated aorta sign, hairy kidney sign, and cystic lesion with ground glass opacity of lung, primary hypothyroidism, and hypergonadotropic hypogonadism. ECD is rare histiocytic neoplasm with wide range of clinical features which often delay the diagnosis. Clinician should be mindful of the various presentations and the classic radiographic and histologic features of ECD. This case highlights the significance of entertaining ECD in any patient presenting with lower leg bone pain and symmetric osteosclerosis of long bones of lower extremities to allow for early diagnosis and treatment.

Atypical presentation of syphilis: Rapidly progressive glomerulonephritis.

Syphilis is a sexually transmitted disease with a wide range of clinical manifestations. With the recent worldwide resurgence of syphilis, it is imperative to recognize various presentations of this great imitator. Renal syphilis is rare and most commonly present as nephrotic range proteinuria associated with pathological features of membranous glomerulonephritis. Rapidly progressive glomerulonephritis (RPGN) is a rare and atypical form of renal syphilis. A 50-year-old Ethiopian woman presented with periorbital swelling, hematuria, proteinuria, and rapidly progressive renal failure. Rapid plasma reagin and confirmatory Treponema pallidum hemagglutination (TPHA) tests were reactive. Treatment with a weekly Benzathine penicillin for 3 weeks resulted in a rapid return of renal function to baseline, with the increasing rate of new syphilis, clinicians should be mindful of the various renal manifestation of syphilis. This case highlights the significance of considering syphilis as a reversible cause in any patient presenting with a clinical feature suggestive of RPGN.

Osteitis Fibrosa Cystica; A Forgotten Manifestation of Secondary Hyperparathyroidism Due to End-Stage Renal Disease: A Case Report.

Introduction: Osteitis fibrosa cystica is a rare complication of secondary hyperparathyroidism. Even though it is thought to be a disease of the past, it still continues to be seen in this modern era in the setting of undiagnosed or untreated chronic kidney disease. Case Presentation: A 26-year-old married Ethiopian women presented with 4 year history of progressive proximal weakness of extremities and diffuse bone pain. Physical examination revealed diffuse bone tenderness and features consistent with myopathy. Blood work up showed raised creatinine, markedly elevated PTH, borderline low calcium, and vitamin D in severe deficiency range. X-Ray findings were consistent with classical skeletal lesion of severe secondary hyperparathyroidism. Conclusion: Osteitis fibrosa cystica is a rare but still frequent complication of secondary hyperparathyroidism, which may be the initial presentation of chronic kidney disease. This case report emphasizes the importance of considering secondary hyperparathyroidism in patients presenting with weakness and bone pain to allow for early diagnosis, treatment, and improvement of overall prognosis.