Predictors of delayed‐type hypersensitivity to Candida albicans and anti‐epstein‐barr virus antibody among children in Kilimanjaro, Tanzania

Abstract

We evaluated sex, age, nutritional status, and infectious disease (ID) as predictors of two biomarkers of cell-mediated immunity (CMI), delayed-type hypersensitivity to Candida albicans (DTH-Candida), and anti-Epstein-Barr virus antibody (EBV Ab), among 200 children in Kilimanjaro, Tanzania. DTH-Candida, which decreases with compromised CMI, was positively associated with age (OR: 1.27; 95% CI: 1.02, 1.57) and triceps skinfold (TSF; OR: 1.16; 95% CI: 1.02, 1.26), and inversely associated with height-for-age Z score (HAZ; OR: 0.86; 95% CI: 0.68, 1.08) and diagnosed ID (OR: 0.48; 95% CI: 0.22, 1.08). There was significant interaction between TSF and ID: DTH-Candida exhibited a strong inverse association with ID among children with low TSF (OR: 0.16; 95% CI: 0.05, 0.50) and a strong positive association with TSF among children with ID (OR: 2.64; 95% CI: 1.29, 5.42). EBV Ab, which increases with compromised CMI, was inversely associated with male sex (β: −0.47; 95% CI: −0.70, −0.24) and TSF (β: −0.04; 95% CI: −0.08, 0.00), and positively associated with HAZ (β: 0.06; 95% CI: −0.03, 0.15). Among males, EBV Ab was positively associated with anemia. Among normal HAZ children, EBV Ab was inversely associated with TSF. There was no association between DTH-Candida and EBVAb. While DTH-Candida provides a direct measure of CMI, our results suggest that interpretation of EBV-Ab among Kilimanjaro children was complicated by its indirect relationship with CMI. Among our sample, CMI increased with age and adequate nutrition and was compromised during acute ID. The suggestive CMI-compromising effect of increasing height-forage may bear further exploration.

Breastfeeding over two years is associated with longer birth intervals, but not measures of growth or health, among children in Kilimanjaro, TZ

“…Breastfeeding ≥2 years was associated with lower AGP ( P < 0.001), but not CRP ( P = 0.933). Other associations with these variables were consistent with our expectations and previous observations: Children with higher TSF were less likely to have clinically‐apparent (physician‐diagnosed) infectious disease ( P = 0.013); older children ( P = 0.007), those with higher TSF ( P = 0.023), and those who had experienced severe infectious disease in the first year of life ( P = 0.075) were more likely to express DTH to C. albicans (Wander et al, ). Increased age was associated with lower CRP (parameter retained by AIC model selection; P = 0.116), as was female sex ( P = 0.035); history of severe infectious disease during infancy was positively associated with both CRP (parameter retained by AIC model selection , P = 0.131) and AGP ( P = 0.012).…”

“…We conducted a secondary analysis of data collected among a cross‐sectional sample of approximately three hundred 2‐ to 7‐year‐old children in Kilimanjaro, Tanzania. The primary purpose of the study was to explore the impact of exposure to infectious agents during early life on immune function and infectious disease morbidity later in childhood (Wander, ; Wander et al, ). Here, we evaluate breastfeeding for greater than 2 years as the main predictor of interest.…”

“…A small amount of pathogen antigen is introduced under the most superficial layers of the skin. Local activation of immunological memory is evident on the skin after approximately 24 h and indicates intact cell‐mediated immunity (Christou et al, ; Wander et al, ) and lower susceptibility to many infectious diseases (Shell‐Duncan and Wood, ).…”

“…After approximately 24 h, the site of the Candin skin test was evaluated for the presence of an induration and induration size was measured in millimeters (mm) across two perpendicular diameters. A mean induration ≥5 mm defined DTH positivity to C. albicans (Wander et al, ).…”

The immune-nutrition interplay in aging – facts and controversies

“…If it was solely a matter of lack of building blocks, all parameters of the immune system should be affected in the same way. Other explanations include a confounding role of infections in influencing immune parameters in malnourished individuals [203], low levels of certain hormones in malnourished children, e.g. leptin [204], prolactin [205] and growth hormone [206], all of which impact growth and function of thymus -an important specialized primary lymphoid organ where T cells mature till puberty.…”