Cranial computed tomography in the emergency department evaluation of HIV-infected patients with neurologic complaints.

STUDY
OBJECTIVE: To demonstrate the usefulness of cranial computed tomography (CT) in the emergency department evaluation of HIV-infected patients and patients with risk factors for HIV infection who present with neurologic complaints.
DESIGN: Retrospective review of imaging reports and medical records of patients who visited the ED from March 1991 through March 1992.
SETTING: Urban university ED. PARTICIPANTS: Patients with HIV infection or risk factors for infection who underwent emergency cranial CT after presenting to the ED with headache, altered mental status, focal deficits, or other neurologic signs or symptoms.
RESULTS: One hundred forty-six patients visited the ED 169 times. Of the 169 cranial CTs obtained, 85 (50%) were normal, 49 (29%) showed atrophy only, and 35 (21%) demonstrated focal lesions, with mass effect noted in ten (6%). Enhancing lesions were present in 13 scans. In 21 (12%) cases, CT revealed either an indication for admission, a contraindication to lumbar puncture, or both. In 25 instances, patients with lesions had nonfocal presentations and no papilledema. Two presentations--focal deficit and altered mental status--were each statistically significantly associated with lesions on CT. In seven patients with multiple ED visits, repeat CT showed new findings. Among patients who had risk factors but were of unknown HIV status, there was the same proportion of abnormal scans as in known HIV-infected patients.
CONCLUSION: CT detected clinically significant neuropathology among our study patients. Because lesions and mass effect were associated with nonfocal as well as focal presentations, CT is indicated in every neurologically symptomatic patient with HIV infection or risk factors for infection. Because HIV-related diseases can progress rapidly, repeat CT is recommended even in patients with recent scans.