Orbital cellulitis as the initial presentation of Langerhans cell histiocytosis in an adult patient

Abstract

A 28-year-old woman presented with 3 weeks of right-sided blurry vision, proptosis, orbital pain, and upper eye lid swelling. She also complained of progressively worsening intermittent headaches. She had been evaluated in the emergency department multiple times for the same complaint, and had received multiple courses of intravenous antibiotics with minimal improvement. Physical examination revealed significant proptosis of the right eye although visual acuity was preserved in both eyes. Initial laboratory studies including complete blood count, basic metabolic panel, and thyroid functioning tests were within normal limits. An infectious workup including blood and fungal cultures were negative. A non-contrast computed tomography (CT) scan of the head demonstrated a mass on the right orbital rim which was concerning for right periorbital and orbital cellulitis, with the post septal component present along the superior and lateral aspects of the right orbit (Figure 1A). Broad spectrum antibiotics were initiated and a repeat magnetic resonance imaging scan performed ten days later showed partial improvement of the inflammatory changes associated with orbital cellulitis. However, there was an interval increase in the size of a more discrete mass-appearing lesion which was now eroding into the adjacent bony structures (Figure 1B). A biopsy of the lesion showed an infiltrate which stained strongly positive for CD1a and S100 (Figure 1C-F). A diagnosis of Langerhans cell histiocytosis (LCH) was considered. CT scans of the chest and abdomen-pelvis and a bone marrow biopsy did not show evidence of systemic LCH disease. She declined therapy and her prognosis is unknown. CNS imaging findings for Langerhans cell histiocytosis (LCH). A: CT head without contrast showed right periorbital edema with underlying, focal cortical destruction of the right superior orbital rim consistent with periorbital cellulitis. B: A MR of the orbits performed 2 weeks later showed an enlargement of the mass with invasion into the orbital rim. The mass is delineated by a yellow star. Subsequent pathology obtained from biopsy of the mass revealed Langerhans's histiocytosis (eosinophilic granuloma). C: Low power view; (E) High power view (cells are medium to large size, with folded/convoluted nuclei, fine chromatin, abundant eosinophilic cytoplasm in a background of eosinophils, neutrophils and small lymphocytes; (D) CD1a positive; (F) S100 positive LCH, previously known as histiocytosis X, describes a spectrum of proliferation of Langerhans cells that may manifest as a single system or multiple system disease. Although solitary ocular manifestations of LCH without evidence of systemic LCH are documented in children, they are rare in adults. The location of the infiltrate within the orbit largely determines the patient's presenting complaints.1 Most orbital manifestations of LCH in adults have been in the context of systemic LCH disease with only a handful of cases of solitary orbital LCH presenting as orbital cellulitis documented. The diagnosis is primarily determined by a biopsy of the presenting lesion, where immunohistochemical staining with S100 and CD1a is characteristic of Langerhans cells.2 Treatment strategies for orbital LCH depend on “case-by-case basis” and surgical resection and radiation is reserved for solitary lesions in children. Given its rarity, ideal management strategies are unclear, however solitary orbital LCH can spread to the central nervous system, and these patients can develop diabetes insipidus and systemic LCH. Aggressive prolonged multi-drug regimens including combinations of vincristine, prednisolone, etoposide, and methotrexate are used for treatment, with routine surveillance for recurrence with history, examination, and imaging. None. Not Applicable Obtained AD drafted and revised the manuscript. AG provided care for the patient and conceptualized the report. AG and HN revised and edited the manuscript for intellectual content.