We retrospectively studied the clinical and laboratory findings of 23 culture positive TBM pts by comparing their clinical characteristics with their isolate's IS6110-based DNA fingerprints (van Embden, 1993) and drug susceptibility.

The mean age of the pts was 16 (70% < 20 years old). The mean duration of illness prior to admission was 26 days. At presentation, the majority of pts had stage 3 disease (70%), while the remainder had stage 2 disease(30%).1 Thirteen pts (57%) were treated for TBM (the remainder died within the first 48 hours). The following data apply to the treated group: 77% survived. Stage 2 pts were more likely to die than stage 3 pts (43% vs. 0%). Pts sick for greater than two weeks preceding admission were more likely to have stage 3 disease (64%) than stage 2 disease and were also more likely to die (27% vs. 0%). Many patients had ocular palsies (69%, most commonly 6th nerve). Seizures were associated with a long duration of illness and poor outcome (33% mortality vs. 14% mortality without seizures).

M. tuberculosis isolates from these pts were “fingerprinted” and the resulting patterns were compared to one another. Of the isolates evaluated, two (9%) had cluster patterns matching one another. Of the 16 isolates whose drug susceptibility data are complete, two are drug resistant (one to Rifampin and one to Isoniazid).

The long duration of illness, the large number of stage 3 pts, and the high mortality imply that these pts became very ill before seeking admission. Improved patient education, along with early hospitalization and prompt intervention, could have changed the outcome for many of these individuals. In this small group of pts, two were infected with clustered isolates. As more isolates are fingerprinted, additional cluster groups will likely be revealed. Epidemiologic analysis of these groups will better define segments of the population at risk for TBM, leading to improved prevention strategies for this often fatal disease.

1. Stage 1 disease = pts who are rational and do not have focal neurologic signs or hydrocephalus; stage 2 disease = pts who have an altered mental status but are not stuporous (i.e. confused pts) or have focal neurologic signs; and stage 3 disease = pts who are stuporous or have paraplegia or dense hemiplegia.