Effect of micronutrient deficiency on QuantiFERON-TB Gold In-Tube test and
tuberculin skin test in diagnosis of childhood intrathoracic tuberculosis.
Author(s): Mukherjee A(1), Saini S(1), Kabra SK(1), Gupta N(2), Singh V(3), Singh S(4),
Bhatnagar S(1), Saini D(1), Grewal HM(5), Lodha R(1); Delhi TB Study group.
Collaborators: Aneja S, Arya T, Bhatnagar S, Chandra J, Dutta AK, Doherty TM,
Friis H, Grewal HM, Hesseling AC, Kabra SK, Lodha R, Marais B, Mukherjee A,
Parashar D, Prajapati S, Purohit K, Saini D, Saini S, Singh RR, Singh S, Singh V.
Affiliation(s): Author information:
(1)Department of Pediatrics, All India Institute of Medical Sciences, New Delhi,
India.
(2)Department of Endocrinology, All India Institute of Medical Sciences, New Delhi,
India.
(3)Department of Pediatrics, Kalawati Saran Children Hospital and Lady Hardinge
Medical College, New Delhi, India.
(4)Division of Clinical Microbiology and Molecular Medicine, Department of
Laboratory Medicine, All India Institute of Medical Sciences, New Delhi, India.
(5)1] Department of Clinical Science, Faculty of Medicine and Dentistry, University
of Bergen, Bergen, Norway [2] Department of Microbiology, Haukeland University
Hospital, Bergen, Norway.
Publication date & source: 2014, Eur J Clin Nutr. , 68(1):38-42
BACKGROUND/OBJECTIVES: Data on performance of QuantiFERON-TB Gold In-Tube test
(QFT) and tuberculin skin test (TST) in children with active tuberculosis from
high burden countries in the context of micronutrient deficiency are scarce. The
objective of this study was to evaluate the effect of micronutrient deficiency on
the performance of TST and QFT in children with intrathoracic tuberculosis.
SUBJECTS/METHODS: Children with probable intrathoracic tuberculosis underwent
TST, QFT, gastric lavages and induced sputum examination for AFB (Acid-Fast
Bacilli) smear and culture. Zinc, copper, ferritin and vitamin D were measured on
stored serum samples. The study used cross-sectional data at initiation of
anti-tubercular therapy.
RESULTS: Three hundred and sixty-two children (median age 115.5 months
(interquartile range: 73, 144), 200 (55.3%) girls) were enrolled in the study.
Microbiological confirmation of tuberculosis could be obtained in 128 patients.
TST and QFT were positive in 337 (93%) and 297 (82%) children, respectively.
Performance of both the tests was unaffected by weight-for-age and height-for-age
'z-scores' or by serum copper levels. TST was not affected by serum zinc and
ferritin levels. Children with negative QFT results had lower mean serum zinc
level (P=0.01) and higher ferritin levels (P=0.007) as compared to those with
positive test. Higher proportion of children with positive TST were vitamin D
deficient/insufficient (P=0.003).
CONCLUSION: Micronutrient status, especially serum levels of zinc, may influence
the performance of QFT in children with intrathoracic tuberculosis. Considering
the high prevalence of zinc deficiency in developing countries, QFT should be
used cautiously for diagnosing tuberculosis.
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