An unusual presentation of eosinophilic granuloma in an adult: a case report.

Eosinophilic granuloma is the most common and benign form of a rare proliferative disorder: Langerhans' cell histiocytosis. Spinal involvement is rare and only 15 adult cases have been reported. We present an unusual variant of eosinophilic granuloma in a 25-year-old woman with radiological evidence of vertebra plana. Plain radiography, magnetic resonance imaging, bone scan, and blood tests were carried out, and a specimen was taken from L4 using computed tomography-guided biopsy. Gram staining, acid fast bacillus smear, bacterial and fungal cultures were negative. Histological examination of the biopsy showed features of eosinophilic granuloma with aggregates of Langerhans histiocytes. The patient was treated with low-grade radiotherapy at 150 cGy per day for 7 days. She was asymptomatic at one-year follow-up although the radiological picture was unchanged.