Study says healthcare shortcomings leave tuberculosis undiagnosed, untreated

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In a prospective autopsy study published in The Lancet of patients who died at a hospital in Lusaka, Zambia, researchers found a large percentage of patients were infected with tuberculosis but had gone undiagnosed and untreated, and 17 percent of patients infected with tuberculosis were indeed infected with multidrug-resistant TB but also remained undiagnosed.

Aiming to assess the burden of pulmonary TB, extrapulmonary TB, undiagnosed subclinical TB, and multidrug-resistant TB, researchers performed autopsies on 125 adults who died in the inpatient general medical wards of the tertiary care referral center. Researchers first performed histopathological examinations to detect rifampicin-resistant TB, and then used the Xpert MTB/RIF assay on tissue samples from patients with detected TB to confirm drug resistance.

Researchers found that of 125 patients, 101 were infected with HIV. They also found 78 patients had TB but only 47 had TB listed as cause of death, which meant 20 patients were infected with TB but had not been diagnosed, and subsequently had not received treatment. Of the 78 patients with TB, 13 had undiagnosed multidrug-resistant TB, and 35 patients had extrapulmonary TB. The risk of extrapulmonary TB was greater among those infected with HIV compared to uninfected patients. Only half of patients infected with HIV had access to antiretroviral therapy at time of death.

Study authors note “the neglected burden of tuberculosis among hospital inpatients might be greater” than in Zambia’s prison population which sees a TB prevalence of 7.6 percent.

“The fact that patients continue to die of tuberculosis at a tertiary care referral center reveals several shortcomings in clinical awareness, recognition, and diagnosis of tuberculosis, coupled with poor laboratory services and an inadequate cascade of tuberculosis health care, from peripheral clinics up to the tertiary care level,” authors wrote.

Study authors call for “more proactive screening for tuberculosis and MDR-TB” worldwide, suggesting screening for TB “on admission for all inpatients, irrespective of admission diagnosis, with the rapid GeneXpert MTB/RIF assay on sputum.”

“Additional screening would go some way to detecting a proportion of the 3 million missed cases of tuberculosis and undiagnosed multidrug-resistant tuberculosis,” authors wrote.

2 thoughts on “Study says healthcare shortcomings leave tuberculosis undiagnosed, untreated

  1. Reuben Granich

    I have not read the article but this also illustrates the huge missed opportunity to prevent TB in people living with HIV. TB is largely preventable in people living with HIV using earlier ART (before people get TB) and IPT. ART reduces the risk by around 65% irrespective of CD4 cell count (Suthar et al) and when IPT is added this reduction is up in the 90’s range. TEMPRANO showed the benefits of immediate ART and IPT–check out the CROI abstract for details. In the future one could only hope that these sorts of articles would be rare as most people get access to early ART and IPT and of course TB treatment if they develop TB (even people on ART can develop TB). We neglect achieving 90-90-90 targets at our peril–TB/HIV interventions contribute to 90-90-90 (early HIV testing of TB patients, getting people on earlier ART, and keeping people virally suppressed) and without improved access to HIV treatment and IPT as part of 90-90-90 push then we will be faced with these sorts of preventable TB and MDR TB public health disasters for people living with HIV and their community.

  2. youjizz

    One may argue that taking a random sample from the 9299 prisoners (the total number of prisoners minus those already on TB treatment), would be a better strategy to quantify the prevalence of undiagnosed TB. However, we would be missing those presumptive TB cases that should immediately be detected and treated. We tried to undertake a mass screening strategy considering the importance of not missing cases, and the high prevalence of TB in this population. But, as we found more presumptive TB cases than expected, we faced financial constraints and hence culture was done for about 68% presumptive TB cases. The remaining presumptive TB cases were also not left as they were; they were immediately referred to nearby health facilities for diagnosis and immediate treatment. The fact that we had extrapolated positive culture results for the presumptive TB cases that weren’t able to obtain cultures was a limitation of this study. However, as we used a representative sample, we trust that our final estimate is accurate. Moreover, we didn’t include chest X-ray examination; instead, we relied on symptomatic screening and hence some prisoners that were unable to produce sputum and those non-symptomatic TB cases which could have been detected by chest X-ray might have been missed. The relatively short study duration and the fact that the duration of a cough had to be at least 2 weeks were also limitations of our study.


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