Brainstem and Spinal Arachnoiditis Ossificans Associated With Neurocysticercosis: A Case Report.

Arachnoiditis ossificans (AO), a very rare entity that can cause severe neurological deficit, is associated with an inflammatory response and compressive effect on the spinal cord. A 65-year-old woman with diagnosis of arachnoiditis ossificans, who had a past medical history of neurocysticercosis diagnosed eight years before the actual onset that was accompanied by obstructive hydrocephalus and required bilateral ventriculoperitoneal shunts, presented with lower limb paresis. The spinal CT reported large calcified subdural spinal plaques. She was treated with high-dose steroids with subsequent improvement of the clinical manifestations. Spinal neurocysticercosis is a rare manifestation of this disease, although the Mexican population is especially prone to it, due to the endemic presence of this entity, it can provoke spinal arachnoiditis. We conclude that the chronic inflammation of the spinal meninges induced by the cysticercosis could encourage the arachnoid cells to go through osteoblastic metaplasia with consequent production of thick calcium deposits, such as those found in AO. Thus it may be associated with AO. We present, to our knowledge, the first patient with AO-associated neurocysticercosis.

Metastatic primary brain rhabdomyosarcoma in a pediatric patient: illustrative case.

BACKGROUND: Primary intracranial rhabdomyosarcoma is an extraordinarily rare malignant tumor, with even fewer presenting with distant metastasis. To date, only five cases, including the one presented here, have been reported to present metastatic activity. OBSERVATIONS: A 12-year-old boy presented with a few days of headache, nausea, vomiting, but no neurological deficit. Brain computed tomography and magnetic resonance imaging demonstrated hydrocephalus and a cystic lesion with left parieto-occipital extension. After resection, pathology reported primary rhabdomyosarcoma, with positive desmin and myogenin on immunohistochemistry. The patient presented with pulmonary metastasis. The patient had an overall survival of 21 months after diagnosis with optimal treatment. LESSONS: Rhabdomyosarcoma is a malignant neoplasm arising from undifferentiated skeletal muscle cells, with morphological, immunohistochemical, ultrastructural, or molecular genetic evidence of primary skeletal muscle differentiation. It presents with a rapidly worsening clinical course and the final outcome is poor. Treatment is widely based on protocols that have been proven to be effective in extracranial versions of these tumors, although repeatedly ineffective. Primary brain rhabdomyosarcoma poses a diagnostic challenge because of its infrequent presentation, grade of undifferentiation and tumor heterogeneity. Immunohistochemical and genetic testing have proven to be useful tools for diagnosis.