[Atypical pseudotumoral neuromeningeal cryptococcosis in an immunocompromised patient treated for pontine glioma. Case report and literature review].

Background And Purpose: We report an atypical feature of neuromeningeal cryptococcosis presenting as spinal cystic arachnoiditis and cerebellar cryptococcoma in a child treated for pontine glioma.

Case Report: In November 2003, we diagnosed a pontine glioma in a six-year-old female child. She was initially treated with radiotherapy (54Gy for six weeks) and dexamethasone until July 2006. From January 2004 to September 2006, the patient received 30 cycles of chemotherapy including vincristine 1.5mg/m(2) Day 1, carboplatin 150mg/m(2) Day 1, and temozolomide 150mg/m(2) Days 2-6 every 28 days. In October 2006, the patient suffered spontaneous acute low back pain radiating into both lower limbs revealing lumbar cystic arachnoiditis and cerebellar cryptococcoma. The cerebrospinal fluid (CSF) sample showed lymphocytic pleocytosis and Cryptococcus neoformans; glucose and protein levels were low. First-line medical treatment including liposomal amphotericin B, then fluconazole effectively decreased the pain. However, in February 2007, she presented with cauda equina syndrome and the spinal MRI showed that the lumbar cyst had increased in size. The patient underwent a lumbar laminectomy and cyst removal. Histology confirmed the arachnoiditis with no cancer cells or pathogenic agents.

Conclusions: Arachnoiditis and cryptococcoma are rare. They can appear to be a brain neoplasm because of their pseudotumoral aspect. Often, the diagnosis can be made from the CSF sample.