by David Douglas

Last Updated: 2007-11-16 14:38:46 -0400 (Reuters Health)

NEW YORK (Reuters Health) – Primary central nervous system vasculitis (PCNSV) appears to be a variable syndrome that consists of several subsets of heterogenous disease, researchers report in an early online issue of the Annals of Neurology.

Dr. Robert T. Brown, Jr., of the Mayo Clinic, Rochester, Minnesota and colleagues sought to further characterize this rare disease that may result in serious neurologic outcomes or death.

"Progress in understanding PCNSV has been slow because its occurrence is infrequent and its identification is difficult to make with certainty," Dr. Brown told Reuters Health.

To investigate further, the team retrospectively examined data on 101 PCNSV patients who were seen at the clinic during a 21-year period.

The median age at diagnosis was 47 years, and diagnoses were made in 75% of patients within half a year after onset of symptoms. Seventy were diagnosed by angiography and the remaining 31 by nervous system biopsy.

Angiography and brain biopsy may complement each other when determining the diagnosis, write the investigators, and early recognition and treatment may reduce poor outcomes.

The majority of patients were treated initially with prednisone and responded favorably. However, about 25% of patients overall relapsed.

"We noted that many patients showed a favorable response to treatment, emphasizing the need for early diagnosis and initiation of therapy that may help avoid serious and irreversible complications," Dr. Brown said.

Most of the patients had multiple manifestations, among them headache, altered cognition and focal neurologic manifestations. Persistent neurologic deficit or stroke and headaches were most common initial symptoms. These affected 68% of patients.

Mortality rates and disability at last follow-up were higher in patients with conditions including cognitive impairment and cerebral infarctions.

The researchers estimate that the incidence of PCNSV is 2.4 per million. The study "begins to answer some essential questions that can clarify diagnosis and hopefully lead to earlier, and successful, management," Dr. Brown concluded.

Ann Neurol 2007.