Patients at Risk for TB Meningitis
HIV-infected individuals are at highest risk for TB meningitis at all CD4 counts, with young children under 4 years representing the second major high-risk group due to rapid disease progression and high rates of dissemination, particularly TB meningitis. 1, 2
High-Risk Populations by Immune Status
HIV/AIDS Patients
- TB meningitis is an important consideration at all CD4 counts in HIV-positive patients, not just those with advanced immunosuppression 1
- HIV-infected patients with CD4 counts <200 cells/mm³ have particularly elevated risk, with mortality reaching up to 70% in HIV co-infected TBM patients 3, 4
- Advanced HIV disease (lower CD4 counts) predicts higher in-hospital mortality in patients presenting with TBM 3
Other Immunocompromised States
- Patients receiving prolonged corticosteroid therapy are at increased risk for TB disease including meningitis 1, 5
- Patients on immunosuppressive therapy, including chemotherapy for cancer and TNF-α antagonists, have elevated risk 1, 5
- Patients with hematologic and reticuloendothelial diseases such as leukemia or Hodgkin's disease 5
- End-stage renal disease patients 5
- Diabetes mellitus patients 5
High-Risk Populations by Age
Young Children
- Children under 4 years of age are at high risk for rapid development of TB disease, particularly TB meningitis 1
- All infants and children younger than 4 years with tuberculin skin test ≥10 mm are candidates for preventive therapy due to meningitis risk 5
Adolescents and Young Adults
- Young adults have a second peak of meningococcal disease in late teens/early 20s, though TB meningitis disproportionately affects younger populations in high-burden settings 1, 2
High-Risk Populations by Medical History and Exposures
Close TB Contacts
- Close contacts of persons with newly diagnosed infectious tuberculosis (tuberculin skin test ≥5 mm) require preventive therapy 5
- Tuberculin-negative children and adolescents who are close contacts within the past 3 months need preventive therapy until repeat testing at 12 weeks 5
Previous TB or Radiographic Evidence
- Persons with abnormal chest radiographs showing fibrotic lesions likely representing old healed tuberculosis (≥5 mm tuberculin reaction) 5
- Patients with pulmonary silicosis 5
Substance Use and Malnutrition
- Intravenous drug users, even if HIV-seronegative (≥10 mm tuberculin reaction) 5
- Patients with substantial rapid weight loss or chronic undernutrition, including intestinal bypass surgery, postgastrectomy state, chronic peptic ulcer disease, chronic malabsorption syndromes 5
- Alcohol dependency creates relative immunocompromise increasing TB risk 1
Geographic and Demographic Risk Factors
- Foreign-born persons from high-prevalence countries who never received BCG vaccine 5
- Medically underserved low-income populations, including high-risk racial or ethnic minority populations (especially Blacks, Hispanics, and Native Americans) 5
- Residents of long-term care facilities including correctional institutions, nursing homes, and mental institutions 5
- Travelers returning from TB-endemic areas, particularly those with relevant travel history to high-burden regions 1
Critical Clinical Pitfall
- Do not wait for advanced immunosuppression to consider TB meningitis in HIV patients—it remains an important consideration at all CD4 counts, unlike cryptococcal meningitis which predominantly occurs at CD4 <100 cells/mm³ 1
- In high HIV/TB co-infection settings, up to 66.7% of meningitis cases may be HIV-positive, with TB representing a major proportion of chronic meningitides 6