Secondary hemophagocytic lymphohistiocytosis with associated central pontine myelinolysis

A 34-year-old previously healthy male presented to the emergency department with an altered mental state and unexplained intermittent fevers persisting for three weeks. Initially, his symptoms mimicked an ear infection, for which he received a prescription for Augmentin. As his condition deteriorated, additional symptoms emerged, including bilateral ear pain, fever, and diffuse headaches. Initial evaluations revealed acute hepatic encephalopathy, mastoiditis, and pancytopenia. Further tests uncovered hepatosplenomegaly, lymphadenopathy, and reactivated EBV. The patient met six of the eight HLH criteria, including fever above 38.3°C, cytopenia, elevated triglyceride and ferritin levels, and a bone marrow biopsy confirming hemophagocytosis. The treatment plan followed the HLH-2004 protocol, involving an eight-week induction therapy using etoposide, dexamethasone, and cyclosporine. Monitoring of disease-specific markers such as ferritin and IL-2R showed improvement. One month later, the patient experienced a throbbing headache, nausea, photophobia, and vision changes. MRI showed abnormal signals consistent with central pontine myelinolysis. Lumbar puncture findings included pleocytosis, elevated total protein, and a substantial EBV viral load, indicative of progressive CNS-HLH with persistent EBV reactivation. The patient is currently undergoing salvage therapy for EBV reactivation, with a poor prognosis for CNS involvement and allogeneic transplant preparations.