Malignant Otitis Externa in a 20-Year-Old Male Patient With Erdheim-Chester Disease: A Case Report.

Malignant otitis externa (MOE) is an uncommon, potentially life-threatening, invasive infection of the external auditory canal and lateral skull base. It is mainly seen in older adults with diabetes or immunocompromised patients and rarely seen in children. Erdheim-Chester disease (ECD) is a rare, non-Langerhans histiocytosis disorder. It is a multisystem disease with a poorly understood etiology. It commonly affects the skeletal system, central nervous system (CNS), cardiovascular system, lungs, retroperitoneum, kidneys, and skin. CNS involvement confers poor prognosis and reduced response to treatment. Cardiovascular involvement is another indicator of poor prognosis. This report describes the case of a 20-year-old male with ECD who had bilateral malignant otitis externa/skull base osteomyelitis and hearing loss. The patient was not responding well to treatment. He was on intravenous antibiotics, underwent left mastoidectomy, received targeted immunotherapy, and had four rounds of chemotherapy. The patient died after six months from the diagnosis and targeted treatment, which indicates the aggressiveness of the disease. MOE should be suspected in any patient presenting with intractable otalgia with otorrhea that is not responsive to local treatment for uncomplicated otitis externa or otalgia with temporomandibular joint (TMJ) pain aggravated by chewing. This is the first report of malignant otitis externa in a young patient with ECD to the best of the author's knowledge. This case emphasizes the importance of suspecting MOE in young patients, especially if the risk factors of the disease are present because early diagnosis can prevent or minimize life-threatening complications.