Killing of Mycobacterium tuberculosis within human monocytes: activation by cytokines and calcitriol.

Human monocytes were isolated and their ability to harbour growth of virulent tubercle bacilli was assessed, in the presence or absence of various immunomodulators. Calcitriol (1,25(OH2), vitamin D3) alone, at doses of 10(-7)-10(-9) M endowed human monocytes with a significant ability to restrict intracellular growth of the tubercle bacilli. Crude immune lymphokines as well as recombinant interferon-gamma (IFN-gamma) endowed monocytes with no tuberculostatic activity. Similarly, other recombinant cytokines tested, notably colony-stimulating factor-1 (CSF-1), interleukin-1 (IL-1), interleukin-3 (IL-3) and interleukin-6 (IL-6) all failed to stimulate anti-tuberculous properties, and even increased growth of the tubercle bacilli in monocytes, in the case of CSF-1. Conversely, incubation of crude lymphokines in combination with calcitriol led to total stasis of the growth of M. tuberculosis. Experiments with recombinant cytokines and immunologically active vitamins showed that a combination of IFN-gamma tumour necrosis factor-alpha and calcitriol induced a significant amount of intramonocyte killing of M. tuberculosis. Addition of this cocktail of factors to already infected monocytes led to substantial killing of tubercle bacilli. These sets of experiments establish clearly that combinations of recombinant cytokines and vitamins may induce substantial intramonocyte killing of M. tuberculosis. The mechanism involved in this killing activity was not clarified.     

Malignant lymphoma of bronchus-associated lymphoid tissue (BALT) coexistent with pulmonary tuberculosis

A case in which malignant lymphoma occurred in association with a tuberculosis focus in a 70-year-old man is reported. Surrounding the epithelioid cell granulomas with caseous necrosis was a dense and diffuse monotonous infiltration of atypical lymphoid cells. Acid-fast bacilli were found in the granulomas and pulmonary tuberculosis was diagnosed. The infiltrating atypical lymphoid cells occasionally invaded the respiratory epithelium producing lymphoepithelial lesions. Immunohistochemically, the lymphoid cells were positive for CD20, and clonal rearrangement of the immunoglobulin heavy chain gene was demonstrated by polymerase chain reaction (PCR). We diagnosed the lesion as a pulmonary malignant lymphoma of bronchus-associated lymphoid tissue (BALT) occurring in the background of tuberculosis. This is the first reported case of pulmonary BALT lymphoma coexistent with pulmonary tuberculosis.     

TB prevention cascade at a district hospital in rural Eastern Cape,South Africa

SETTING:Rural Eastern Cape, South Africa.OBJECTIVE:To identify steps in the TB preventive care cascade from routinely collected data among TB patients at a district hospital prior to the implementation of a novel TB program.DESIGN:This was a retrospective study. We adapted the TB prevention cascade to measure indicators routinely collected at district hospitals for TB using a cascade framework to evaluate outcomes in the cohort of close contacts.RESULTS:A total of 1,722 charts of TB patients were reviewed. The majority of patients (87%) were newly diagnosed with no previous episodes of TB. A total of 1,548 (90%) patients identified at least one close contact. A total of 7,548 contacts were identified with a median of 4.9 (range 1–16) contacts per patient. Among all contacts identified, 2,913 (39%) were screened for TB. Only 15 (0.5%) started TB preventive therapy and 122 (4.4%) started TB treatment. Nearly 25% of all medical history and clinical information was left unanswered among the 1,722 TB charts reviewed.CONCLUSION:Few close contacts were screened or started on TB preventive therapy in this cohort. Primary care providers for TB care in district health facilities should be informed of best practices for screening and treating TB infection and disease.     

Hybrid Approach to Estimation of Underreporting of Tuberculosis Case Notification in High-Burden Settings With Weak Surveillance Infrastructure: Design and Implementation of an Inventory Study

BackgroundThe greatest risk of infectious disease undernotification occurs in settings with limited capacity to detect it reliably. World Health Organization guidance on the measurement of misreporting is paradoxical, requiring robust, independent systems to assess surveillance rigor. Methods are needed to estimate undernotification in settings with incomplete, flawed, or weak surveillance systems. This study attempted to design a tuberculosis (TB) inventory study that balanced rigor with feasibility for high-need settings.ObjectiveThis study aims to design a hybrid TB inventory study for contexts without World Health Organization preconditions. We estimated the proportion of TB cases that were not reported to the Ministry of Health in 2015. The study sought to describe TB surveillance coverage and quality at different levels of TB care provision. Finally, we aimed to identify structural-, facility-, and provider-level barriers to notification and reasons for underreporting, nonreporting, and overreporting.MethodsRetrospective partial digitalization of paper-based surveillance and facility records preceded deterministic and probabilistic record linkage; a hybrid of health facilities and laboratory census with a stratified sampling of HFs with no capacity to notify leveraged a priori knowledge. Distinct extrapolation methods were applied to the sampled health facilities to estimate bacteriologically confirmed versus clinical TB. In-depth interviews and focus groups were used to identify causal factors responsible for undernotification and test the acceptability of remedies.ResultsThe hybrid approach proved viable and instructive. High-specificity verification of paper-based records in the field was efficient and had minimal errors. Limiting extrapolation to clinical cases improved precision. Probabilistic record linkage is computationally intensive, and the choice of software influences estimates. Record absence, decay, and overestimation of the private sector TB treatment behavior threaten validity, meriting mitigation. Data management demands were underestimated. Treatment success was modest in all sectors (R=37.9%–72.0%) and did not align with treatment success reported by the state (6665/8770, 75.99%). One-fifth of TB providers (36/178, 20%) were doubtful that the low volume of patients with TB treated in their facility merited mastery of the extensive TB notification forms and procedures.ConclusionsSubnational inventory studies can be rigorous, relevant, and efficient in countries that need them even in the absence of World Health Organization preconditions, if precautions are taken. The use of triangulation techniques, with minimal recourse to sampling and extrapolation, and the privileging of practical information needs of local decision makers yield reasonable misreporting estimates and viable policy recommendations.     

Effects of Coronavirus Disease Pandemic on Tuberculosis Notifications,Malawi

The coronavirus disease (COVID-19) pandemic might affect tuberculosis (TB) diagnosis and patient care. We analyzed a citywide electronic TB register in Blantyre, Malawi and interviewed TB officers. Malawi did not have an official COVID-19 lockdown but closed schools and borders on March 23, 2020. In an interrupted time series analysis, we noted an immediate 35.9% reduction in TB notifications in April 2020; notifications recovered to near prepandemic numbers by December 2020. However, 333 fewer cumulative TB notifications were received than anticipated. Women and girls were affected more (30.7% fewer cases) than men and boys (20.9% fewer cases). Fear of COVID-19 infection, temporary facility closures, inadequate personal protective equipment, and COVID-19 stigma because of similar symptoms to TB were mentioned as reasons for fewer people being diagnosed with TB. Public health measures could benefit control of both TB and COVID-19, but only if TB diagnostic services remain accessible and are considered safe to attend.     

Fecal Excretion of Mycobacterium leprae,Burkina Faso

Mycobacterium leprae was detected by optical microscopy, fluorescent in situ hybridization, and molecular detection in feces collected for the diagnosis of Entamoeba coli enteritis in a leprosy patient in Burkina Faso. This observation raises questions about the role of fecal excretion of M. leprae in the natural history and diagnosis of leprosy.     

基于季节性ARIMA模型的新疆肺结核发病预测分析

目的 探讨季节性时间序列模型(autoregressive integrated moving average,ARIMA)在新疆肺结核发病预测中的应用,并验证模型的可行性和适用性。 方法 采用季节性ARIMA(p, d, q )(P, D, Q)_s拟合2005年1月—2019年8月新疆地区肺结核月发病人数,建立多个季节时间序列模型并进行比较,选出最优模型对2019年9—12月肺结核发病人数进行预测。 结果 2005年1月—2019年8月新疆地区肺结核累积发病人数为627 869例,年平均发病人数为3 567例。 新疆地区肺结核月发病数具有季节性,1—5月平均发病数高于平均水平,6—12月平均发病数低于平均水平,发病高峰为1月和3月,发病低谷为9月。通过赤池信息量(Akaike Information Criterion,AIC)和贝叶斯信息量(Bayesian Information Criterion,BIC)最小原则得出,ARIMA(1, 1, 1 )(0, 1, 2)₁₂是最优模型,其残差序列为白噪声,参数的回归系数均具有统计学意义,拟合的平均绝对百分比误差MAPE为8.723%。预测的MAPE为18.674%,真实值均处于预测值的95%置信区间内。 结论 ARIMA(1, 1, 1 )(0, 1, 2)₁₂模型能够较好地拟合新疆肺结核发病数据,并进行短期预测,对新疆卫生防控措施的制定具有一定指导意义。     

Novel 6-Month Treatment for Drug-Resistant Tuberculosis,United States

The US Food and Drug Administration approved a 6-month regimen of pretomanid, bedaquiline, and linezolid for extensively drug-resistant or multidrug-intolerant tuberculosis after a trial in South Africa demonstrated 90% effectiveness 6 months posttreatment. We report on a patient who completed the regimen using a lower linezolid dose.     

Effectiveness of Preventive Therapy for Persons Exposed at Home to Drug-Resistant Tuberculosis,Karachi, Pakistan

In Karachi, Pakistan, a South Asian megacity with a high prevalence of tuberculosis (TB) and low HIV prevalence, we assessed the effectiveness of fluoroquinolone-based preventive therapy for drug-resistant (DR) TB exposure. During February 2016–March 2017, high-risk household contacts of DR TB patients began a 6-month course of preventive therapy with a fluoroquinolone-based, 2-drug regimen. We assessed effectiveness in this cohort by comparing the rate and risk for TB disease over 2 years to the rates and risks reported in the literature. Of 172 participants, TB occurred in 2 persons over 336 person-years of observation. TB disease incidence rate observed in the cohort was 6.0/1,000 person-years. The incidence rate ratio ranged from 0.29 (95% CI 0.04–1.3) to 0.50 (95% CI 0.06–2.8), with a pooled estimate of 0.35 (95% CI 0.14–0.87). Overall, fluoroquinolone-based preventive therapy for DR TB exposure reduced risk for TB disease by 65%.