BACKGROUND: Erdheim-Chester disease is a rare non-Langerhans-cell histiocytosis of unknown etiology with multi-organ involvement.

CASE REPORT: A 19-year-old woman presented with orthopnea, severe fatigue, bilateral exophthalmos, and gradual loss of vision. She had anemia and mild leucocytosis related to chronic illness. Marked left side pleural effusion and massive pericardial effusion with bilateral hydronephrosis were detected by plain X-ray, echocardiography, and computed tomography, respectively. Retro-orbital tissue and bone marrow biopsy revealed histiocytic infiltration, which was CD68-positive and CD1a-negative.

CONCLUSIONS: This report describes the first case presentation of Erdheim-Chester disease in our country. This case report may advance our understanding of an orphan disease. Our patient’s young age and stable clinical status may allow long-term follow-up of treatment results.

Keywords: Dyspnea - etiology, Blindness - etiology, Egypt, Erdheim-Chester Disease - diagnosis, Exophthalmos - etiology, Hydronephrosis - etiology, Pericardial Effusion - etiology, Pleural Effusion - etiology, Rare Diseases - diagnosis, young adult