Changing trends in the epidemiology of pediatric lead exposure: interrelationship of blood lead and ZPP concentrations and a comparison to the US population

Severe lead poisoning requiring hospitalization: A case report

Cases of severe childhood lead poisoning (a blood lead level (BLL) ≥45 mcg/dL) in the United States have decreased with time. Clinicians will encounter such cases only rarely. When such cases arise, however, recognizing their complexities and identifying resources that can help in management are important. We present here a case of severe childhood lead poisoning, highlighting the variable presentation, the rebound phenomenon of BLL after chelation, the usefulness of the zinc protoporphyrin as an adjunctive monitoring parameter, and the importance of early involvement of an inter-professional team.

Maternal and Infant Supplementation with Small-Quantity Lipid-Based Nutrient Supplements Increases Infants' Iron Status at 18 Months of Age in a Semiurban Setting in Ghana: A Secondary Outcome Analysis of the iLiNS-DYAD Randomized Controlled Trial

Background

Interventions are needed to address iron deficiency in low-income settings.

Objective

This secondary outcome analysis aimed to compare the hemoglobin (Hb) and iron status [zinc protoporphyrin (ZPP)] of children born to women enrolled in the iLiNS-DYAD trial in Ghana.

Methods

Women ≤20 wk pregnant (n = 1320) were assigned to receive 60 mg Fe/d and 400 µg folic acid/d until delivery and placebo thereafter, and no supplementation for infants (IFA group); or multiple micronutrients containing 20 mg Fe/d until 6 mo postpartum and no supplementation for infants (MMN); or small-quantity lipid-based nutrient supplements (SQ-LNSs) containing 20 mg Fe/d until 6 mo postpartum, and SQ-LNSs for infants from 6 to 18 mo of age (LNS). We compared infants' Hb (g/L) and ZPP (µmol/mol heme) at 6 and 18 mo of age.

Results

At 6 mo of age, groups did not differ in mean ± SD Hb (overall: 113 ± 9.9 g/L) or geometric mean (95% CI) ZPP [overall: 62.6 (60.6, 64.7)]. At 18 mo of age, mean ± SD Hb (overall: 112 ± 10.4 g/L) did not differ significantly between groups, whereas geometric mean (95% CI) ZPP was lower (P = 0.031) in the LNS group [53.9 (50.7, 57.3)] than the IFA [60.4 (56.7, 64.3)] but not the MMN [58.8 (55.6, 62.2)] group. Further, the LNS group, compared with the IFA and MMN groups combined, had a lower prevalence of elevated (>70) ZPP (27.5% compared with 35%; P = 0.02) and a marginally lower prevalence of anemia (38.7% compared with 44.9%; P = 0.06). These results generally remained unchanged when controlling for prespecified covariates or correcting for inflammation.

Conclusions

In this setting, providing SQ-LNSs or multiple micronutrients with 20 mg Fe/d, compared with iron (60 mg/d) and folic acid, to pregnant women does not affect their infants' Hb or iron status at 6 mo of age, but maternal and infant supplementation with SQ-LNSs increases infants' iron status at 18 mo of age. This trial was registered at clinicaltrials.gov as NCT00970866.

Comparative effectiveness of zinc protoporphyrin and hemoglobin concentrations in identifying iron deficiency in a group of low-income, preschool-aged children: practical implications of recent illness

OBJECTIVE

The goal was to assess the influence of recent infection on screening tests for iron depletion (zinc protoporphyrin and hemoglobin) among low-income, preschool-aged children.

METHODS

This cross-sectional study was conducted at community sites and ambulatory care clinics in Hartford, Connecticut, and included 180 preschool-aged children. Iron depletion was defined as serum ferritin levels of < or = 15 microg/L. Recent illness was defined by parent or guardian (caretaker) report or evidence of elevated C-reactive protein concentrations. History of anemia was determined through medical records review. Sensitivity, specificity and positive predictive values of hemoglobin and zinc protoporphyrin were calculated overall and for children with and without recent illness.

RESULTS

At enrollment, more than one half of the children had a recent illness, and 57.5% had a history of anemia. More than one third had iron depletion. Serum ferritin levels were significantly higher among recently ill children. Secondary to recent illness, the positive predictive value of elevated zinc protoporphyrin, but not low hemoglobin, was reduced significantly. Zinc protoporphyrin levels of >69 micromol/mol heme identified significantly more iron-deficient children.

CONCLUSIONS

Compared with anemia, elevated zinc protoporphyrin levels identified significantly more iron-deficient children. Recently ill children were one half as likely to have low serum ferritin levels, compared with children without recent illness. The negative effect of recent illness on the positive predictive value of zinc protoporphyrin when ferritin is used to determine iron status has many practical implications.