Central nervous system nocardiosis with granulomatous pachymeningitis and osteomyelitis of skull vault.

A 34-year-old immunocompetent man weighing 95 kg was operated for a small left parietal scalp swelling in the year 2002. He was well until 2008, when he developed chronic diffuse headache, vomiting and drowsiness. The left parietal dura and overlying vault biopsy showed evidence of granulomatous pachymeningitis with osteomyelitis secondary to nocardiosis. He had responded well to inadequate antibiotic therapy. After a dormant period of 3 years, there was recrudescence of severe raised intracranial tension symptoms in 2011. Magnetic resonance imaging showed diffuse pachymeningeal thickening mainly involving the occipital dura, posterior falx, and tentorium cerebelli. In addition, well-defined small nodules with hypointense signals on both T1- and T2-weighted images were seen in occipital lobes. Patient was treated with three drug regime with good recovery at 3 months follow-up. This is a rare case of central nervous system nocardiosis with skull vault osteomyelitis and a protracted clinical course.