A common presentation – turning out as an uncommon diagnosis: From hip pain to Langerhans cell histiocytosis

• Published in: The American journal of the medical sciences 2022-09, Vol.364 (3), p.353-358
• Main Authors: Volis, Ina, Livneh, Ido, Zohar, Yaniv, Raz-Pasteur, Ayelet
• Format: Article
• Language: English
• Subjects: Adult; Adult Langerhans cell histiocytosis; Arthralgia; BRAF; Female; High risk Langerhans cell histiocytosis; Histiocytosis, Langerhans-Cell - diagnosis; Histiocytosis, Langerhans-Cell - diagnostic imaging; Humans; Lung - pathology; Lytic lesions; Magnetic Resonance Imaging; Middle Aged; Multi-system Langerhans cell histiocytosis; Pain - etiology; Tomography, X-Ray Computed
• ISSN: 0002-9629; 1538-2990
• DOI: 10.1016/j.amjms.2022.04.014

Langerhans cell histiocytosis (LCH) is an uncommon clonal proliferation of myeloid progenitor cells, it is especially rare in adults. We present a case of multi-system LCH in a 53-year-old woman, the sole symptom of which was prolonged, non-resolving hip pain for 18 months prior to the diagnosis. Initial evaluation included imaging studies aimed at identifying a presumed local etiology. X-ray demonstrated non-specific arthritic changes on the left femur. Computed tomography (CT) and magnetic resonance imaging (MRI) scans identified a lytic lesion at the same location, warranting a systemic workup. After non-invasive investigations failed to reveal the underlying etiology, a biopsy was performed, revealing cores of Langerhans cells that stained positive for both CD1a and langerin. These findings verified the surprising, uncommon diagnosis of LCH. A comprehensive workup was conducted in order to determine the extent of the disease and its molecular nature – revealing a BRAFV600E-positive, high-risk, multi-system LCH with skeletal, lung and liver involvement.