(708) Multisystem Involvement of Langerhans Cell Histiocytosis

Introduction: Langerhans Cell Histiocytosis (LCH) is an exceedingly rare hematologic-based malignancy with varying presentation based on systems affected. While more common in children, the annual incidence in adults is 1-2 cases/1 million people with 50% of cases involving the bone marrow, lungs, liver, gastrointestinal tract, and spleen. A smaller number of cases affect the nervous system, usually characterized by either mass lesions of the hypothalamus, pituitary or pineal glands. We describe a case involving numerous organ systems and its complex workup.

Description: A 33-year-old man presented with encephalopathy, hypernatremia and presumed sepsis. CT of the head revealed an area of hypodensity concerning for a mass. Follow up MRI of the brain demonstrated a diffuse, homogenous T2FLAIR hyperintense lesion with heterogeneous enhancement involving the hypothalamus and median eminence with extension to mammillary bodies. A CT chest/abdomen/pelvis, ordered due to sepsis, demonstrated inflammatory and cystic lung nodules as well as concentric wall thickening of the intrahepatic biliary ducts and porta hepatitis. Additionally, his skin exhibited severe ulcerations and erythematous plaques of the groin folds and anogenital region. His testing consisted of a bronchoscopy, skin biopsy, and lumbar puncture (LP). Skin biopsy was consistent with BRAF negative LCH, thus avoiding the need for neurosurgical biopsy. To note, the only pertinent finding of his LP was elevated cerebrospinal fluid (CSF) levels of soluble IL-2 receptor (sIL-2R). Chemotherapy was initiated with cytarabine and methotrexate. A follow up MRI brain 3 months later showed reduction in size of the hypothalamic lesion.

Discussion: An adult male presented with manifestations of panhypopituitarism from a hypothalamic mass and hepatobiliary, pulmonary, and skin abnormalities suggesting LCH. Providers should consider LCH in patients with endocrinopathies (central diabetes insipidus and hypothyroidism) and an enhancing hypothalamic mass and conduct a thorough testing for additional organ involvement. Additionally, while not providing a definitive diagnosis, sIL-2R may be a reasonable CSF marker to utilize when central nervous system hematologic malignancies are suspected, helping to narrow the differential diagnoses.