Study setting

RRHs are tertiary hospitals that, in addition to in-and out-patient care, offer specialist clinical, radiological and surgical services. Each hospital serves 10 districts, a population of about 2 500 000, and has medical out-patient clinics which see 7000–10 000 patients each month. An HIV/ART clinic attached to each medical out-patient clinic serves 3000–5000 active TB patients.2 The out-patient clinics are serviced by fully functioning laboratories equipped with fluorescence microscopy (FM) and Xpert.

The results of all sputum samples tested in these laboratories were recorded in the hospitals' TB laboratory registers. TB treatment is offered at all RRHs using internationally recommended fixed-dose regimens provided by the Uganda NTLP, and is recorded in the hospitals' TB treatment register.

From January 2012 to December 2014, Xpert testing was sequentially introduced at all RRHs in Uganda. Five of these hospitals were included in the study based on the availability and completeness of data 6 months before and 6 months after the introduction of Xpert. These hospitals serve large rural populations in Eastern, Northern and Western Uganda. Before the introduction of Xpert, presumptive TB patients with a smear-negative result were started on anti-tuberculosis treatment if they 1) had a chest X-ray suggestive of TB, 2) did not respond to a 2-week course of antibiotics, or 3) if the health care worker made a clinical decision to start them on anti-tuberculosis treatment (Figure 1). After the introduction of Xpert, presumptive TB patients with a negative smear result were recommended for Xpert testing if they were HIV-positive or their HIV status was not known. Patients with a positive Xpert test were started on treatment for drug-susceptible TB if their disease was rifampicin (RMP) susceptible or, if their disease was RMP-indeterminate or -resistant they were referred for drug susceptibility testing and subsequent treatment for drug-resistant TB. Patients who were negative on Xpert were referred back to health care workers to be assessed and treated for another possible cause of their symptoms (Figure 1).

Algorithms for TB diagnosis in Uganda before and after implementation of Xpert^® MTB/RIF testing. TB=tuberculosis; HIV=human immunodeficiency virus; +=positive; CXR=chest X-ray; AFB = acid-fast bacilli; MTB = M. tuberculosis; RIF = rifampicin; −= negative; DST = drug susceptibility testing.