Parasitic infection may be associated with discordant responses to QuantiFERON and tuberculin skin test in apparently healthy children and adolescents in a tuberculosis endemic setting, Ethiopia

Abstract

BackgroundM. tuberculosis remains one of the world’s deadliest pathogens in part because of its ability to establish persistent, latent infections, which can later reactivate to cause disease. In regions of the globe where disease is endemic, as much as 50% of the population is thought to be latently infected, complicating diagnosis and tuberculosis control. The tools most commonly used for diagnosis of latent M. tuberculosis infection are the tuberculin skin test and the newer interferon-gamma release assays, both of which rely on an antigen-specific memory response as an indicator of infection. It is clear that the two tests, do not always give concordant results, but the factors leading to this are only partially understood.MethodsIn this study we examined 245 healthy school children aged from 12 to 20 years from Addis Ababa, a tuberculosis-endemic region, characterised them with regard to response in the tuberculin skin test and QuantIFERON™ test and assessed factors that might contribute to discordant responses.ResultsAlthough concordance between the tests was generally fair (90% concordance), there was a subset of children who had a positive QuantIFERON™ result but a negative tuberculin skin test. After analysis of multiple parameters the data suggest that discordance was most strongly associated with the presence of parasites in the stool.ConclusionsParasitic gut infections are frequent in most regions where M. tuberculosis is endemic. This study, while preliminary, suggests that the tuberculin skin test should be interpreted with caution where this may be the case.

Interferon‐gamma release assays can effectively screen migrants for the tuberculosis infection, but urgent, active cases need clinical recognition

“…We found the highest rate of IGRA positivity (18%) in group one, which contained paediatric immigrants from Somalia and was comparable to the 25% QFT positivity rate reported for Ethiopian schoolchildren at a median age of 15 years (11). The second highest rate (8.4%) was found in other high-incidence countries, which was comparable with the QFT positivity of 10% at a median age of seven in migrant children from two high-burden countries, Africa and India (2).…”

Infectious diseases prevalence, vaccination coverage, and diagnostic challenges in a population of internationally adopted children referred to a Tertiary Care Children's Hospital from 2009 to 2015

“…Available data on association between parasitic infections and TST and QFT-G-IT results are poor [34,65] : Wassie and colleagues screened 245 healthy school children from Addis Abeba, a TB-endemic region, with TST and QFT-G-IT. Although concordance between the tests was generally fair (90%), there was a subset of children who had positive QFT-G-IT with negative TST and a strong association with the presence of parasites in the stool of these patients.…”

“…Although concordance between the tests was generally fair (90%), there was a subset of children who had positive QFT-G-IT with negative TST and a strong association with the presence of parasites in the stool of these patients. [65] Piñeiro-Pérez et al did not found differences in TST results among 1074 infected and noninfected children. [34] In our univariable and multivariable analyses, we did not find an association between parasite infection and positive result of TST or of QFT-G-IT, nor with eosinophilia.…”

Schistosoma mansoni Infection Can Jeopardize the Duration of Protective Levels of Antibody Responses to Immunizations against Hepatitis B and Tetanus Toxoid

“…Helminth infections have also been implicated in diminished or altered immune responses to a number of other infectious diseases including malaria [13] [14], Helicobacter pylori [15], HIV [16,17], and Mycobacterium . tuberculosis [18]. Also, S .…”