Lymphocytic meningitis following insertion of a porcine dermis dural graft.

We describe a case of lymphocytic meningitis following insertion of a porcine dermis implant to repair an operative dural defect. Histology of the excised implant revealed local abscess formation with a granulomatous reaction. Oligoclonal Immunoglobulin G, part of which could be removed by absorbtion with the porcine dermis, was present in the patient's cerebrospinal fluid, and, to a less marked degree, in his serum. The cerebrospinal fluid glucose was markedly depressed. An unusual hypersensitivity reaction to the porcine implant was considered the most likely explanation for this meningitic illness. The patient went on to make a full recovery following excision of the implant.