Immunopathogenesis in HIV-associated pediatric tuberculosis

Incidence and Risk Factors of Tuberculosis among Children Receiving Antiretroviral Therapy in Northwest, Ethiopia

Objectives

Tuberculosis (TB) is a significant global health issue, especially for children living with HIV/AIDS. Hence, the objective of this study was to determine the incidence of TB among children on Anti-retroviral treatment (ART) and its predictors in Northwest Ethiopia.

Methods

A retrospective follow-up study was conducted among 428 children on ART using simple random sampling from patient registries (2011-2020). STATA statistical software was used for data analysis. The Cox regression model was used to explore predictors of TB infection.

Result

The study found that the incidence density of TB was 3.37 cases per 100 person-years. The risk factors for TB incidence among children on ART included a history of contact with active TB cases, missed isoniazid preventive therapy, advanced HIV/AIDS stages according to WHO clinical staging, poor drug adherence, and incomplete vaccination status.

Conclusion

The incidence of TB among children on ART is high, particularly within the first year of enrollment. Children with incomplete vaccination, poor adherence, missed isoniazid prophylaxis, a history of TB contact, and advanced WHO clinical stage are at an increased risk of TB incidence.

Clinical characteristic, common sites, and geographical distribution of pediatric tuberculosis patients in Southwest China

Background

The data report of a large sample, dynamic epidemiology, and characteristic analysis of pediatric tuberculosis (TB) in Southwest China is not clear. Herein, we conducted descriptive dynamic epidemiology, characteristic analysis and geographical distribution study of pediatric TB inpatients in Southwest China for more than 20 years.

Methods

Patients with pediatric TB were recruited from October 2002 to September 2022 in Southwest of China based on etiology or clinical confirmation. Extract hospitalization medical record information for each patient. The geographical distribution chart of cases is used to display the trend of case flow segmented every 5 years.

Results

Among 3,024 pediatric TB patients with an average age of 9.11 ± 4.39, 17.49% (529) had pulmonary tuberculosis (PTB), 9.06% (274) had extrapulmonary tuberculosis (EPTB), and 73.45% (2,221) had combined TB. The most common form of EPTB is disseminated TB (28.98%), followed by TB lymphadenitis (20.56%), pleural TB (19.72%), and TB meningitis (19.68%). Children aged 0-4 years had a high risk of TB meningitis and a severe symptoms, while children in the elderly age group had a high risk of pleural TB. In the past 20 years, hospitalized TB pediatric cases mainly came from Sichuan, Tibet, Qinghai, Yunnan and other places. The number of patients from ethnic minorities, especially Tibetans, showed an upward trend on a yearly basis (χ2 = 401.43, P < 0.001).

Conclusions

Public health investment and effective management in pediatric TB should be further strengthened.

Maternal HIV infection drives altered placental Mtb-specific antibody transfer

Introduction

Placental transfer of maternal antibodies is essential for neonatal immunity over the first months of life. In the setting of maternal HIV infection, HIV-exposed uninfected (HEU) infants are at higher risk of developing severe infections, including active tuberculosis (TB). Given our emerging appreciation for the potential role of antibodies in the control of Mycobacterium tuberculosis (Mtb), the bacteria that causes TB, here we aimed to determine whether maternal HIV status altered the quality of Mtb-specific placental antibody transfer.

Methods

Antigen-specific antibody systems serology was performed to comprehensively characterize the Mtb-specific humoral immune response in maternal and umbilical cord blood from HIV infected and uninfected pregnant people in Uganda.

Results

Significant differences were noted in overall antibody profiles in HIV positive and negative maternal plasma, resulting in heterogeneous transfer of Mtb-specific antibodies. Altered antibody transfer in HIV infected dyads was associated with impaired binding to IgG Fc-receptors, which was directly linked to HIV viral loads and CD4 counts.

Conclusions

These results highlight the importance of maternal HIV status on antibody transfer, providing clues related to alterations in transferred maternal immunity that may render HEU infants more vulnerable to TB than their HIV-unexposed peers.