COVID-19 and Chronic Diabetes: The Perfect Storm for Reactivation Tuberculosis?

A Case Series

Genesis P. Aguillón-Durán; Ericka Prieto-Martínez; Doris Ayala; Juan García Jr.; John M. Thomas III; Juan Ignacio García; Brandon Michael Henry; Jordi B. Torrelles; Joanne Turner; Eder Ledezma-Campos; Blanca I. Restrepo


J Med Case Reports. 2021;15(621) 

In This Article


The coronavirus disease 2019 (COVID-19) pandemic is predicted to become a double-edged sword for tuberculosis (TB) control.[1] On the positive side, comprehensive preventive measures against COVID-19 such as self-quarantine, social distancing, and use of face masks is likely to reduce the spread of Mycobacterium tuberculosis. However, there is an anticipated net negative effect of COVID-19 on TB control, including an increase in the number of TB cases and deaths, and the proportion of drug-resistant TB.[1] Two types of interrelated factors can contribute: the first type are programmatic issues that affect all TB patients in a community. These include the lockdown of TB diagnosis and treatment services, and the redirection of the already limited resources for national TB programs worldwide to address the urgency of the COVID-19 pandemic. A model estimated that between 2020 and 2025 there will be a global excess of active TB cases (3.1–10.7%) and deaths (4–16%) as a result of the COVID-19 pandemic, setting back global TB control efforts by at least 8 years.[2]

The second type are biological or social factors that can contribute to the hypothesized bidirectional synergy between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Mycobacterium tuberculosis.[3] First, both microbes primarily target the lung. Second, both share social risk factors (for example poverty, overcrowding, malnutrition, and poor access to healthcare), which increase the risk of disease transmission, progression, and poor TB treatment outcomes.[4,5,6] Third, both diseases share biological risks, such as male gender or diabetes. Diabetes increases the risk of TB development or adverse treatment outcomes, and is also a risk factor for more severe COVID-19 presentation and increases the risk of death.[4,7–9] Fourth, there is reported immunosuppression in COVID-19 patients that would be expected to favor M. tuberculosis growth. These include reduction in CD4 and CD8 counts, functional exhaustion of these T cells[10] and heightened production of interleukin (IL)-10 in response to the viral infection,[11] and the widespread, often unregulated and inappropriate use of immunosuppressive treatments (for example steroids, tocilizumab) in many countries.[12] Thus, the convergence of these biosocial factors would be expected to increase the risk of adverse outcomes for COVID-19 or TB. However, clinical evidence is still limited, albeit beginning to show support. The first published cohort of COVID-19 and TB provides examples of TB preceding, overlapping, or following COVID-19 infection.[13] Some studies have reported more severe TB disease, delayed recovery, and higher death in patients with both TB and COVID-19.[3,4,13–15] Likewise, TB prevalence was higher among patients with severe COVID-19, when compared with nonsevere cases.[3] Thus, the need for integrated care of both types of diseases and, hence, knowledge of the individual risk factors that retro-feed on each other.

However, to date, the role of COVID-19 in boosting TB development is yet to be established.[3] We describe our findings in three individuals with newly diagnosed TB after recovery from COVID-19 (Table 1). These cases alert to the heightened risk for reactivation TB in patients recovering from COVID-19 with a chronic history of poorly controlled diabetes.