The Influence of Mining and Human Immunodeficiency Virus Infection Among Patients Admitted for Retreatment of Tuberculosis in Northern Tanzania

Abstract

Abstract. In tuberculosis (TB)-prevalent settings, patients admitted for retreatment of TB may account for a high burden of poor treatment outcome. We performed a retrospective cohort study to characterize retreatment patients and outcomes at a TB referral hospital in northern Tanzania. From 2009 to 2013, 185 patients began a retreatment regimen, the majority for relapse after prior treatment completion. Men accounted for an unexpected majority (88%), 36 (20%) were human immunodeficiency virus (HIV) infected and for 45 (24%) mining was their primary occupation. A poor outcome (death, default, or persistent smear positivity after 7 months of treatment) was found in 37 (23%). HIV infection was the only significant predictor of poor outcome (adjusted odds ratio [aOR] = 2.50, 95% confidence interval [CI] = 1.07-5.83, P = 0.034). Interventions to minimize need for retreatment or improve retreatment success may be regionally specific. In our setting, community-based diagnosis and management among at-risk subpopulations such as miners and those HIV infected appear of highest yield.In Tanzania, like many tuberculosis (TB) endemic countries, patients categorized as undergoing retreatment for TB account for proportionally the highest rates of death, treatment failure, and default among all TB patients excluding those with known drug resistance.1 The national estimate for treatment success rate in human immunodeficiency virus (HIV)-negative patients without prior treatment was 90%, but was 80% in patients with a history of TB treatment.1 Patients undergoing retreatment are often prescribed the World Health Organization (WHO) Category II regimen of extended total duration, which contains the daily intramuscular injection of streptomycin, a medication with considerable cumulative side effects including ototoxicity and vestibular toxicity that may further compromise treatment completion. Kibong'oto Infectious Diseases Hospital (KIDH) is a regional referral hospital for retreatment TB cases, and the national referral hospital for multidrug-resistant (MDR) TB. The Mererani region includes numerous small-scale mining operations, principally involved in the mining of the precious gemstone tanzanite. The mines are run with low-level mechanization, use roughly 8,000 transient workers, and are situated in a community of approximately 200,000 people with interdependence on the mining industry.3 The mining occupation in other TB-endemic settings has been associated with high rates of HIV coinfection, comorbid lung disease such as silicosis and risk of TB reinfection.4 Perception suggests that miners account for a considerable number of patients admitted to KIDH for retreatment and may account for a greater proportion of those with poor retreatment outcome.We therefore sought to perform a retrospective cohort study of all patients admitted to KIDH for a retreatment regimen over the past 5 years to define the local burden of retreatment, clinical characteristics among retreatment patients, and predictors of retreatment outcome.The hospi...

High mortality during tuberculosis retreatment at a Ghanaian tertiary center: a retrospective cohort study

“…We found that when mortality occurred, it was early in RT-TB therapy. While one study in Tanzanian RT-TB patients found 6.5% mortality in the first two months [13], we observed over 10% mortality within the first fifteen days of therapy. This high early mortality rate likely reflects late advanced disease presentations.…”

Risk factors for the treatment outcome of retreated pulmonary tuberculosis patients in China: an optimized prediction model

“…The standard WHO recommended retreatment regimen (category II) for PTB is an economic and TPR, true-positive rate (sensitivity); TNR, true-negative rate (specificity); PPV, positive predictive value; NPV, negative predictive value. efficient regimen [24][25][26]. However, in past two decades, the collaborative researches were conducted in many countries have provided a lot of evidence that patients ultimately failed with standard retreatment regimen [27][28][29][30][31][32].…”

“…The standard WHO recommended retreatment regimen (category II) for PTB is an economic and efficient regimen [24–26]. However, in past two decades, the collaborative researches were conducted in many countries have provided a lot of evidence that patients ultimately failed with standard retreatment regimen [27–32].…”

Prevalence and factors associated with tuberculosis among the mining communities in Mererani, Tanzania

“…[4,5,9] Small-scale miners have relatively high risk of getting TB as a result of inadequate ventilation, significant exposure to respirable crystalline silica, HIV infection, in some cases poor nutrition and alcohol abuse. [6,10] Tuberculosis transmission is favoured in poorly ventilated, dark and humid environment as is the case in most of the small-scale mining pits. As miners carry a huge TB prevalence, they also pose high risk to the surrounding communities they come into contact with.…”

“…Locally at Mererani mines, the prevalence of TB among tanzanite miners has been reported to be well higher compared to the general population. [10] The SSM are generally all men, with no standard time of the daily working shifts, almost all don't use standard personal protective equipments and just a few will use locally improvised nose and mouth protective cloths while working. [11] This study aimed to determine the current prevalence of TB among the mining communities in Mererani, situated in Simanjiro District, northern Tanzania and assess factors associated with TB.…”