EXPERIENCE WITH BRAIN BIOPSY IN ACQUIRED IMMUNE-DEFICIENCY SYNDROME-RELATED FOCAL LESIONS OF THE CENTRAL-NERVOUS-SYSTEM

Involvement of the central nervous system (CNS) in patients with acqui red immune deficiency syndrome (AIDS) is an increasing clinical proble m. The most common brain complications are toxoplasmosis (50-70 per ce nt), primary CNS lymphoma (20-30 per cent) and progressive multifocal leucoencephalopathy (10-20 per cent). Almost two-thirds of these condi tions can be treated, early diagnosis and therapy leading to survival with a good quality of life. Although clinical and neuroradiological c riteria alone may have high predictive value, they are not sufficient to distinguish the broad spectrum of diseases reliably. Consequently, biopsy appears necessary for definite diagnosis in some cases. The pot ential role and timing of brain biopsy have been assessed. Twenty-four of 50 human immunodeficiency virus-seropositive patients with focal c erebral lesions were considered for biopsy between October 1991 and De cember 1992. Twelve underwent brain biopsy, seven stereotactic and fiv e ultrasonographically guided. A diagnosis was achieved in 11 patients : six primary lymphoma, three progressive multifocal leucoencephalopat hy, and one mycotic and one tuberculous abscess. Both techniques prove d to be safe and reliable, with a 92 per cent diagnostic rate. These d ata confirm the usefulness of biopsy in patients with AIDS with its wi de range of associated cerebral lesions that require different aggress ive treatments. On the basis of this preliminary experience and report s in the literature, it is considered that brain biopsy is indicated f or patients with focal enhancing cerebral mass lesions seen on compute d tomography and magnetic resonance imaging who do not respond to an a ppropriate trial of empirical antitoxoplasmosis therapy and for those showing rapid clinical deterioration in whom imaging and serology do n ot suggest toxoplasmosis.