Hypertrophic pachymeningitis in an immunocompetent adult with positive Aspergillus DNA in the cerebrospinal fluid

A 42-year-old immunocompetent man presented with subacute onset unilateral headache and associated lower cranial nerve palsies. Cranial magnetic resonance imaging showed enhancing thickened tentorium cerebelli and subtentorial dura mater. Cerebrospinal fluid examination revealed lymphocytic pleocytosis and positive polymerase chain reaction assay of Aspergillus DNA. While on voriconazole treatment a progressive increase was noted in subtentorial pachymeningeal hypertrophy, which was excised because of critical compression of the medulla. The excision material showed extensive fibrosis, cellular infiltrates and no organisms. With combination therapy with anti-fungal agents and corticosteroids, pachymeningitis showed regression. We hypothesised that intact immune status and less burden of Aspergillus infection in this patient may have resulted in a chronic progressive hypertrophic pachymeningitis.