Emergency department presentation of idiopathic intracranial hypertension

Idiopathic intracranial hypertension (IIH), or pseudotumor cerebri, is a sy ndrome characterized by an elevated intracranial pressure in the absence of a focal lesion, infective process, or hydrocephalus. New onset IIH may pre sent to the emergency department in a variety of ways. To describe the etio logic associations and clinical features in this disorder, we performed a r etrospective analysis of consecutive emergency department patients with new onset IIH during the calendar years 1987-1996. A total of 52 patients met all study criteria. The mean patient age was 27 +/- 8.9 years; the female t o-male ratio was 7:1. An etiologic association could he identified in 85% o f cases and included obesity, hypertension, drugs, endocrine, and systemic disorders. Headache was a dominant complaint in most patients (48/52) and a ssociated with dizziness, nausea, and/or visual complaints. Fourteen patien ts (27%) were not diagnosed on their initial ED visit and were more likely to have atypical clinical features (71% vs. 24%; P = .004). Atypical featur es included paraesthesias, neck/back pain, unilateral headache, vertigo, an d nystagmus. Papilledema, the ophthalmoscopic hallmark of IIH, was not dete cted initially in 11 patients (21%), These results suggest that IIH is a re latively uncommon neurological illness that may have a variety of causes. T he emergency department diagnosis may be complicated by atypical clinical f eatures and a lack of detectable papilledema. (C) 1999 by W.B. Saunders Com pany.