Mycobacterium tuberculosis bacteraemia: experience from a non-endemic urban centre

Area of Science:

• Infectious Diseases
• Microbiology
• Public Health

Background:

• Mycobacterium tuberculosis bacteraemia is often associated with human immunodeficiency virus (HIV) co-infection.
• Cases are predominantly reported in developing countries, with variable impacts on tuberculosis (TB) mortality.
• Limited data exists on risk factors for TB bacteraemia in developed nations.

Purpose of the Study:

• To investigate clinical, sociodemographic, and behavioral risk factors in patients with M. tuberculosis bacteraemia.
• To compare these factors between patients with positive and negative blood cultures.
• To assess the association between M. tuberculosis bacteraemia and mortality in a US population.

Main Methods:

• Nested case-control analysis within a 9-year population-based active TB surveillance study.
• Comparison of patients with M. tuberculosis positive blood cultures to those with negative blood cultures.
• Inclusion of patients with and without mycobacterial blood cultures.

Main Results:

• HIV infection was more prevalent in patients with positive mycobacterial blood cultures (79.8% vs. 15.1%).
• Patients with M. tuberculosis bacteraemia had higher mortality rates (50.0% vs. 17.0%).
• Risk factors included men-who-have-sex-with-men behavior, renal failure, and high HIV RNA levels.

Conclusions:

• M. tuberculosis bacteraemia in HIV-infected individuals is associated with increased mortality.
• Mycobacterial blood cultures are more frequently requested in HIV-infected patients.
• Identifying risk factors is crucial for managing TB bacteraemia, especially in co-infected populations.