Implementing rapid testing for tuberculosis in Mozambique

Area of Science:

• Medical diagnostics
• Infectious disease epidemiology
• Public health interventions

Background:

• Sputum smear microscopy, the primary method for diagnosing pulmonary tuberculosis in Mozambique, exhibits low sensitivity, particularly in individuals with HIV.
• A significant proportion of tuberculosis cases remain undiagnosed and untreated, exacerbated by limited testing for drug-resistant tuberculosis strains.

Purpose of the Study:

• To evaluate the implementation and impact of rapid molecular testing using Xpert® MTB/RIF for tuberculosis diagnosis in Mozambique.
• To assess the increase in tuberculosis case detection and identification of rifampicin resistance in smear-negative samples.

Main Methods:

• Introduction of Xpert® MTB/RIF testing for smear-negative sputum samples in four public hospitals.
• Establishment of a sputum transportation system and training for laboratory technicians and clinicians.
• Deployment of polymerase-chain-reaction-based assay for simultaneous detection of Mycobacterium tuberculosis and rifampicin resistance.

Main Results:

• Xpert® MTB/RIF identified an additional 1081 (69%) tuberculosis cases among smear-negative individuals.
• Rifampicin resistance was detected in 5% of these newly identified cases.
• Treatment initiation rates were lower for patients diagnosed with Xpert® (67%) compared to microscopy (82%), and 25% of Xpert® modules failed calibration within 15 months.

Conclusions:

• Rapid molecular testing shows promise for improving tuberculosis diagnosis, especially in HIV-co-infected populations.
• Significant logistical challenges, including the need for more affordable and durable testing platforms, hinder widespread implementation.
• Ensuring prompt treatment initiation and completion for all tuberculosis patients, including those with drug-resistant strains, is critical.