Clinical and Radiological Characteristics of Tuberculous Meningitis in the Central Hospital

Background: Tuberculosis (TB) manifests as tuberculous meningitis (TBM) in up to 5% of extrapulmonary cases, causing significant morbidity and mortality. In Mexico, the prevalence is 0.35 cases per 100,000. Diagnosis is challenging due to the gradual onset and low TB levels in CSF. Mortality is around 20%, higher in HIV patients. Material and Methods: A cross-sectional, retrospective, descriptive study was performed with patients treated at the Central Hospital "Dr. Ignacio Morones Prieto" who were diagnosed with TBM from 2018 to 2023. Patient records that met the following criteria were included: a) age over 18 years, b) any gender, c) confirmed diagnosis of TBM through staining, bacteriological culture, molecular studies, or biopsy, and d) brain imaging study using CT or MRI. Results: Thirty-three patient files were evaluated. GeneXpert PCR, which was positive (only) in 17 of the cases (51.5%), culture (Lowenstein-Jensen) positive (only) in 6 patients (18.2%), cranial meninges biopsy (only) in 2 of the cases (6.1%) and bacilloscopic study in 1 patient (3.0%). Two positive results (GeneXpert and culture) were obtained in 7 patients (21.2%). There was a statistically significant correlation for mortality in those patients who presented stupor (100%) vs. those who did not present drowsiness only (33.0%) or remained awake (0%) (p<0.001). On the other hand, the statistically significant correlation between the presentation of cerebral edema and mortality was very striking since 93.8% of the patients who did not present edema survived, and 100% of those who presented edema died (p=0.001). Lumbar puncture findings included pleocytosis, hypoglycorrhachia (<30 mg/dL), and elevated protein (0.2 to 5 g/dL). Severe hypoglycorrhachia (<25 mg/dL) was associated with hydrocephalus and altered consciousness. Conclusions: This study provides a clinical and demographic overview of TBM in San Luis Potosí, Mexico, highlighting the need for more comprehensive data collection and larger sample sizes to better characterize the disease.