Confirmation and extension of association of blood lead with attention-deficit/hyperactivity disorder (ADHD) and ADHD symptom domains at population-typical exposure levels

Background:  Recent studies have suggested that child attention-deficit/hyperactivity disorder (ADHD) and its symptom domains are related to blood lead level, even at background exposure levels typical in western countries. However, recent studies disagreed as to whether lead was related to inattention or hyperactivity-impulsivity within the ADHD domain. More definitive evaluation of these questions was sought.
Methods:  Two hundred and thirty-six (236) children aged 6–17 years participated (61 ADHD-Combined type, 47 ADHD Predominantly Inattentive type, 99 non-ADHD control, 29 unclassified borderline, situational, or not otherwise specified (NOS) cases). Formal diagnosis was reliably established by a best estimate procedure based on a semi-structured clinical interview and parent and teacher ratings. Lead was assayed from whole blood using inductively coupled plasma mass spectrometry with a method detection limit of .3 μg/dL.
Results:  Blood lead levels were slightly below United States and Western Europe population exposure averages, with a mean of .73 and a maximum of 2.2 μg/dL. This is the lowest level of blood lead ever studied in relation to ADHD. After statistical control for covariates including IQ and prenatal smoking exposure, blood lead was associated with ADHD-combined type but not inattentive type. Parent and teacher report indicated association of blood lead with Conners cognitive problems, but only teacher report showed effects on DSM-IV inattention symptoms. Blood lead was associated with hyperactivity-impulsivity in parent report regardless of measurement method, whereas teacher report effects depended on child treatment history.
Conclusions:  These findings confirm that in children with typical US population lead exposure, careful identification of children with ADHD also identifies children with slightly elevated blood lead.     

The Fremantle lead study part 2

Aim: A 1993 study of blood lead levels (BLLs) in pre‐schoolers living in Fremantle showed 25% had BLLs ≥ 10 µg/dL. This study compares the 1993 BLLs with a sample of contemporary Fremantle pre‐schoolers. Methods: Pre‐schoolers (0–5 years) living in the Fremantle area were recruited from hospital and community settings during 2005. As in the 1993 study, guardians completed a questionnaire concerning demographic, environmental and behavioural variables. BLLs were determined by the same method used in 1993. Statistical analysis compared the 1993 and 2005 samples according to demographic variables and dichotomised BLL. Multivariate linear regression was used to control for confounding variables, and linear regression was used to identify risk factors in the 2005 sample. Results: Community (40) and hospital (60) participants provided blood and completed questionnaires; none had BLLs ≥10 µg/dL. Compared with the 1993 sample, 2005 participants were younger, fewer were aboriginal, more had occupied their homes for over 6 months and more had a habit of putting soil in their mouths. After controlling for these variables, the geometric mean BLL in 2005 remained significantly lower than the 1993 value (1.83 and 6.82 µg/dL respectively). As in 1993, aboriginality, presence of participants during home renovation, occupancy of home less than 6 months and living <200 m from a main road were associated with higher mean BLLs. Conclusions: The reassuring decline in the mean BLL between the1993 and 2005 samples is likely associated with the phasing out of leaded petrol. Future research should concentrate on monitoring groups at higher risk.     

Lack of association of delta-aminolevulinic acid dehydratase genotype with blood lead levels in environmentally exposed children of Uygur and Han populations

Aim: A cross‐section study was conducted to explore the association between polymorphism of δ‐aminolevulinic acid dehydratase (ALAD) and lead poisoning in Uygur and Han children in China. Methods: The ALAD genotyping was determined by PCR‐RFLP in 443 Uygur and 469 Han children aged 6–10 years from Urumqi in Xinjiang province. Results: The blood lead levels of 912 environmentally exposed children ranged from 0.5 to 48.2 μg/dL, with a mean of 5.45 μg/dL and a standard deviation of 0.22 μg/dL, and 23. Thirty‐one percent individuals were with blood lead level ≥10 μg/dL. The mean and standard deviation of blood lead levels were 5.57 ± 0.223 μg/dL and 5.30 ± 0.224 μg/dL in Uygur and Han children, respectively. The frequencies of the allele ALAD1 and ALAD2 in Uygur subjects were 90.52% and 9.48%, and in Han subjects were 95.73% and 4.27%, respectively (chi‐square = 19.55, p < 0.05). No statistic correlation between the distribution of ALAD alleles and the blood lead level was found in both populations. Conclusion: A significant difference was seen in the frequency distribution of ALAD genotype between the different races. The genetic susceptibility of ALAD polymorphism to lead toxicity may exhibit in a lead dose‐dependent manner.     

Lead exposure and its association with pubertal development in school-age Egyptian children: Pilot study

Background:  The aim of the present study was to determine blood lead levels in a group of Egyptian school-age children and assess its relationship to pubertal development.
Methods:  Forty-one children were recruited from high- and low-pollution areas in Cairo, Egypt. Sexual maturation was evaluated using Tanner score. Measurements of blood lead and serum levels of follicle stimulation hormone (FSH), luteinizing hormone (LH), estradiol in girls and testosterone in boys were performed for included subjects.
Results:  A total of 51.2% of children had high blood lead levels (≥10 µg/dL). Boys with high lead levels had delayed pubertal maturation compared to those with low lead levels. Breast staging of sexual maturation was significantly delayed in girls with high lead levels. FSH and LH were significantly reduced in children of both sexes, and testosterone levels were reduced in boys with high lead.
Conclusion:  These findings consolidate the cumulative medical evidence of the deleterious effect of high lead levels on pubertal development, possibly through the hypothalamic–pituitary–gonadal axis.     

Community characteristics associated with elevated blood lead levels in children

OBJECTIVES: To identify community characteristics associated with children having elevated blood lead levels (> or = 10 micrograms/dL) and examine whether these characteristics can be used to identify children with elevated blood lead levels. PARTICIPANTS AND SETTING: A total of 20,296 children in Monroe County, New York (< 6 years old) who had blood lead testing in the first 12 months after statewide mandated reporting of blood lead tests began. DESIGN: A logistic regression analysis was conducted to examine the association of children's blood lead levels and community characteristics by using community characteristics of 653 census block groups. RESULTS: The following community level variables were associated with increased risk of elevated blood lead levels in children: residence within the city [odds ratio (OR), 2.0; 95% confidence interval (CI), 1.6, 2.7]; block groups with a higher proportion of individuals of Black race (OR, 1.6; CI, 1.4, 2.0); higher screening rate (OR, 1.9; CI, 1.6, 2.4); lower housing value (OR, 1.6; CI, 1.2, 2.0); housing built before 1950 (OR, 1.5; CI, 1.3, 1.8); higher population density (OR, 1.5; CI, 1.3, 1.8); higher rates of poverty (OR, 1.4; CI, 1.2, 1.8); lower percent of high school graduates (OR, 1.3; CI, 1.1, 1.6), and lower rates of owner-occupied housing (OR, 1.2; CI, 1.0, 1.4). Community characteristics were comparable with clinic-based individual risk assessment to identify children with elevated blood lead levels. CONCLUSIONS: These data demonstrate that community characteristics can be used to develop screening strategies to identify children who have elevated blood lead levels and shift our efforts toward identifying houses containing lead hazards before occupancy and before children are unduly exposed.     

SERIAL DETERMINATIONS OF SERUM FERRITIN IN CHILDREN WITH ACUTE LYMPHOBLASTIC LEUKEMIA Evaluation of its Usefulness as a Prognostic Index

Abstract. Thirty children with acute lymphoblastic leukemia were monitored with serial serum ferritin determinations for up to 17 months. In children with acute lymphoblastic leukemia before initiation of therapy, or in relapse, the mean serum ferritin concentration was 636 μg/l. In children who went into primary remission, the mean serum ferritin concentration fell from 265 μg/l prior to start of treatment, to 161 μg/l after 3 months of treatment. Five patients relapsed. Their serum ferritin levels prior to the relapses ranged from 7 to 135 μg/l. At the time of relapse a further increase in serum ferritin was found in only 2 of the children. Thus, whereas high serum ferritin levels may signal disease activity in acute lymphoblastic leukemia, a normal serum ferritin level does not exclude disease activity or impending relapse.     

Environmental lead exposure during early childhood

OBJECTIVE: To determine the relative contribution of residential lead hazards to children's blood lead concentrations during early childhood. METHODS: We enrolled children 6 months of age and followed them until 24 months of age. Blood and samples of dust, soil, water and paint were analyzed for lead at 6-month intervals, and interviews were conducted to estimate nutritional, behavioral, and demographic factors linked with lead exposure. RESULTS: Of the 276 children enrolled, 249 (90%) were followed until 24 months of age. The geometric mean blood lead concentration of children at 6 months of age was 2.9 microg/dL (95% CI, 2.7-3.1). At 24 months of age, children's mean blood lead was 7.5 microg/dL; 82 (33%) had a blood lead level of > or = 10 microg/dL. In adjusted analyses, lead-contaminated floor dust, soil, and water contributed to children's lead intake throughout the first 2 years of life (P < .05). Lead-contaminated dust from window troughs was a source of lead exposure, especially in the second year of life. Dietary iron intake, but not calcium intake, was inversely associated with blood lead levels (P < .05). Blood lead concentration was over 50% higher in black than in white children (P = .0001). CONCLUSION: Lead-contaminated house dust is the major source of lead intake during early childhood. Black children remain at increased risk for higher blood lead concentration after adjusting for environmental lead exposures and dietary intake.     

Effects of elevated blood lead levels in preschool children in urban Vellore

Objectives

To study the burden and associated risk factors for elevated blood lead levels among pre-school children (15–24 months) in urban Vellore, and to study its effects on child cognition and anemia.

Design

An investigative study through Mal-ED cohort.

Setting

Eight adjacent urban slums in Vellore, Tamil Nadu.

Participants

251 babies recruited through Mal-ED Network.

Outcome measures

Blood lead levels using Graphite Furnace Atomic Absorption Spectrophotometry method at 15 and 24 mo; hemoglobin estimation by azidemethemoglobin method; cognitive levels using Bayley Scales of Infant Development III.

Results

Around 45% of children at 15 months and 46.4% at 24 months had elevated blood lead levels (>10 μg/dL). Among children who had elevated blood lead levels at 15 months, 69.2% (45/65) continued to have elevated levels at 24 months. After adjusting for potential confounders, children from houses having a piped drinking water supply and houses with mud or clay floors were at significantly higher risk of having elevated blood lead levels at 15 months. Thirty one percent (21/67) of the children with elevated blood lead levels had poor cognitive scores. Children with elevated blood lead levels at 15 months had higher risk (Adjusted OR 1.80; 95% CI 0.80–3.99) of having poorer cognitive scores at 24 months. More than half of the children (57%) were anemic at 15 months of age, and elevated blood lead levels were not significantly associated with anemia.

Conclusions

Elevated blood lead levels are common among preschool children living in urban slums of Vellore. Poorer conditions of the living environment are associated with elevated lead levels.     

Iron deficiency as a risk factor for first febrile seizure

We conducted this study to determine the role of iron deficiency as a risk factor for first febrile seizure in children. Fifty children between 6 months to 6 years with first febrile seizure (Cases) and 50 children with febrile illness but without convulsions (Controls) were enrolled from the pediatric ward of a tertiary care hospital. Iron deficiency was determined by estimation of hemoglobin, red blood cell indices and serum ferritin. The mean serum ferritin level (μg/L) was significantly low in Cases (31.9 ± 31.0) as compared to Controls (53.9 ± 56.5) with P = 0.003. Iron deficiency could be a potential risk factor for febrile seizure in children.     

Selenium status of New Zealand infants fed either a selenium supplemented or a standard formula

Objective: New Zealand soils are deficient in the essential micronutrient, selenium. New Zealand infants have low selenium levels at birth and experience a further decline if fed cows milk based formula. This study examined the selenium status of infants fed with a new commercially available selenium supplemented formula.
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age.     

Haemophilus influenzae type b antibodies in vaccinated and non-vaccinated children

Background: Invasive Haemophilus influenzae type b (Hib) infection has a high morbidity among young children, but the burden of disease and rate of Hib are different in different regions. The aim of the present study was to investigate the levels of Hib antibodies and the oropharyngeal Hib prevalence in young children.
Methods: One hundred-fifty nine healthy children aged 19–36 months of age were included in this cross-sectional study. Anti-polyribosylribitol phosphate (anti-PRP) antibody concentrations were measured using commercially available enzyme-linked immunosorbent assay (ELISA), and serotyping of isolated Hib strains was conducted by slide agglutination with specific antisera.
Results: Of the study participants, 57 (35.8%) were fully vaccinated (group 1A); 17 (10.7%) were incompletely vaccinated (group 1B), and 85 (53.5%) were non-vaccinated (group 2). Geometric mean titer (GMT) of anti-PRP antibody was 3.8 μg/mL, 2.2 μg/mL and 0.49 μg/mL in group 1A, group 1B and group 2, respectively. While all children in group 1 ( n  = 74) had seroprotective antibody concentrations (≥0.15 μg /mL), of the children in group 2 ( n  = 85) 31.8% did not have seroprotective anti-PRP levels ( P  < 0.0001). A total of 68.2% in group 2 had natural immunity. Nineteen children (33.3%) in group 1, and 46 (54.1%) in group 2 had oropharyngeal Hib colonization ( P  = 0.0004).
Conclusions: Hib conjugate vaccine is immunogenic and reduces Hib colonization. Each country should investigate the burden of Hib disease and the natural immunity in young children, and should determine antigenic dose, number of doses administered and dose intervals before deciding whether to introduce Hib conjugate vaccine in routine immunization programs.     

Effect of living in lead mining area on growth

Objective Blood lead level BLL and growth parameters including weight and height, in children, living in lead mining area was surveyed. Methods Two groups of 7–11 yr old children, including 45 from a lead mining area (Angooran-Zanjan Province-Iran) and 36 from control area (similar area to the study area, but not lead mining: Ijrood-the same province), were selected to assess BLL (by atomic absorption spectrometry) and growth parameters. Results In the children of the study and control areas, mean BLLs were 36.97±24.67 (μg/dL; mean ± SD) and 15.57 ± 13.35 (μg/dL; mean±SD), respectively (P=0.0005). No significant correlation was found between BLL in children and their fathers’ occupation. In addition, there was no significant difference in growth parameters, including weight and height, in the children of two groups. Conclusion Regarding the results of this study, environmental exposure due to living in lead mining area can lead to increased BLL in children. In addition, our results suggest there is no significant effect of BLL on growth parameters in children in lead mining area. Since some clinical and sub clinical problems are strongly probable when BLL is increased, special attention of the relevant organizations, and more research about the problem and its outcome, is recommended.     

Evaluation of risk assessment questions used to target blood lead screening in Illinois

OBJECTIVE: Beginning in 1995, Illinois law permitted targeted-as opposed to universal-blood lead screening in low-risk areas, which were defined by ZIP code characteristics. State guidelines recommended specific lead risk assessment questions to use when targeting screening. This study was designed to evaluate the sensitivity and specificity of Illinois lead risk assessment questions. DESIGN: Parents bringing their 9- or 10- or 12-month and 24-month-old children for health supervision visits at 13 pediatric practices and parents of children (aged 6 through 25 months and who needed a blood lead test) receiving care at 5 local health departments completed a lead risk assessment questionnaire concerning their child. Children had venous or capillary blood lead testing. Venous confirmation results of children with a capillary level >/=10 micrograms/dL were used in analyses. CHILDREN: There were 460 children with both blood and questionnaire data recruited at the pediatric practices (58% of eligible) and 285 children (51% of eligible) recruited at local health departments. Of the 745 children studied, 738 provided a ZIP code that allowed their residence to be categorized as in a low-risk (n = 456) or high-risk (n = 282) area. RESULTS: Sixteen children (3.5%) living in low-risk areas versus 34 children (12.1%) living in high-risk areas had a venous blood lead level (BLL) >/=10 micrograms/dL; 1.8% and 5.3%, respectively, had a venous BLL >/=15 micrograms/dL. For children living in low-risk areas, Illinois mandated risk assessment questions (concerning ever resided in home built before 1960, exposure to renovation, and exposure to adult with a job or hobby involving lead) had a combined sensitivity of.75 for levels >/=10 micrograms/dL and.88 for levels >/=15 micrograms/dL; specificity was.39 and.39, respectively. The sensitivity of these questions was similar among children from high-risk areas; specificity decreased to.27 and.28, for BLLs >/=10 micrograms/dL and >/=15 micrograms/dL, respectively. The combination of items requiring respondents to list house age (built before 1950 considered high risk) and indicate exposure to renovation had a sensitivity among children from low-risk areas of.62 for BLLs >/=10 micrograms/dL with specificity of.57; sensitivity and specificity among high-risk area children were.82 and.36, respectively. For this strategy, similar sensitivities and specificities for low and high-risk areas were found for BLLs >/=15 micrograms/dL. CONCLUSIONS: The Illinois lead risk assessment questions identified most children with an elevated BLL. Using these questions, the majority of Illinois children in low-risk areas will continue to need a blood lead test. This first example of a statewide screening strategy using ZIP code risk designation and risk assessment questions will need further refinement to limit numbers of children tested. In the interim, this strategy is a logical next step after universal screening.     

Comparison of morbidities in very low birthweight and normal birthweight infants during the first year of life in a developing country

Objective : To compare the morbidities in the very low birthweight (VLBW; < 1500 g) and normal birthweight (NBW; ± 2500 g) Malaysian infants during the first year of life.
Methodology : Prospective observational cohort study of consecutive surviving VLBW infants and randomly sampled NBW infants born in the Kuala Lumpur Maternity Hospital between 1 December 1989 and 31 December 1992. Infants were followed up regularly during the first year of life, after correction for prematurity.
Results : Compared with NBW infants ( n = 106), VLBW infants ( n = 127) had significantly higher risk of failure to thrive (odds ratio [OR] = 8.0, 95% confidence intervals [Cl]: 1.1 to 354.3), wheezing (OR = 3.7, 95% Cl: 1.6 to 9.3), rehospitalization (OR = 2.3, 95% Cl: 1.1 to 5.0), cerebral palsy (OR = 8.6, 95% Cl: 2.0 to 77.6), neurosensory hearing loss (OR = 12.0, 95% Cl: 1.7 to 513.6) and visual loss (7.9 vs 0%, P = 0.002). The mean mental developmental index (MDI) and mean psychomotor developmental index (PDI) at 1 year of age were significantly lower among VLBW infants (MDI 99 [SD = 28], PDI89 [SD = 25]) than NBW infants (MDI 106 [SD = 18], PDI 101 [SD = 18]) (95% Cl for difference between means being MDI: -14.1 to -1.7; and PDI: -17.6 to -6.0). Logistic regression analysis showed that among VLBW infants: (i) male sex, Malay ethnicity and bronchopulmonary dysplasia were significant risk factors associated with wheezing; (ii) longer duration of oxygen therapy during the neonatal period, seizures after the post-neonatal period and wheezing were significant risk factors associated with rehospitalization; and (iii) longer duration of oxygen therapy during the neonatal period was a significant risk factor associated with adverse neurodevelopmental outcome during the first year of life.
Conclusions : Compared with NBW infants, VLBW Malaysian infants had significantly higher risks of physical and neurodevelopmental morbidities.     

Blood lead levels of children with pica and surma use

Blood lead levels of 253 Delhi children were estimated by dithizone method. In 82 (controls) children with no symptoms mean blood lead level was 9.6 μg/dl (±SD 6.8: median 10 μg); only 6 had high levels between 30–33 μg/dl. In 88 children with pica, the mean blood lead level was 23.0 μg/dl (±SD 13.82; median 17 μg) which was significantly higher than the control; 26 had high levels between 30–92 μg/dl. Sixteen children with pica and surma- use and 46 children suspected of lead poisoning showed lead level patterns like the pica group. However, 21 surma-using children without pica resembled the control group. Children with pica were significantly more anemic than the controls and showed higher prevalence of abdominal-neurological symptoms. Because, in India, blood lead cannot be estimated in most of the hospitals, it is suggested that children with severe pica, anemia, abdominal-neurological symptoms and exposure to surma or lead, be suspected of lead poisoning, kept in lead-free environment with corrected nutrition, and be given a short cautious therapeutic trial with oral penicillamine.     

Interaction of iron deficiency and lead and the hematologic findings in children with severe lead poisoning

Microcytic anemia, long considered an effect of lead poisoning, may in fact result from coexisting iron deficiency. In this study, how RBC size, hemoglobin, and zinc protoporphyrin vary as a function of iron status in a group of children with high lead levels was examined. Charts of all children (N = 51) admitted to Cook County Hospital for treatment of lead poisoning in 1981 to 1983 were reviewed for data on age, blood lead level, hemoglobin concentration, MCV, transferrin saturation and zinc protoporphyrin level. The mean lead level was 86 micrograms/dL and the range was 63 to 190 micrograms/dL. Children with transferrin saturation values less than 7% had a mean MCV of 56 microL, hemoglobin of 8.9 g/dL, and zinc protoporphyrin of 693 micrograms/dL; for those with saturations of 7% to 16%, the values were 61 microL, 10.1 g/dL, and 581 micrograms/dL, respectively; the children with saturations greater than 16% had normal mean MCVs and hemoglobin concentrations (74 microL and 11.4 g/dL) and a mean zinc protoporphyrin value of 240 micrograms/dL (P less than .0005). Multiple linear regression was used to correct for effect of age, and transferrin saturation remained the most important predictor of MCV, hemoglobin, and zinc protoporphyrin levels; the addition of lead did not improve the models. Results of this study suggest that iron deficiency is strongly associated with some of the observed toxicities of lead. Also, lead poisoning can exist without producing microcytosis or anemia, and zinc protoporphyrin concentration may not be a sensitive indicator of lead level in the absence of iron deficiency.     

湖南省城镇学龄前儿童血铅水平流行病学调查

目的：调查湖南省城镇学龄前儿童血铅水平及影响因素,为儿童铅中毒的防治提供科学依据。方法：2008年9月至2009年6月整群随机抽取湖南省12个地区城镇学龄前儿童2 044名,男1 108名,女936名,年龄2～6岁,平均4.4±1.1岁。采用原子吸收光谱法测定末梢血血铅水平, 并采用《中国部分城市儿童铅中毒防治项目调查表》进行问卷调查。Logistic回归分析血铅水平的影响因素。结果：湖南省学龄前儿童平均血铅值为81.9±34.5 μg/L。血铅水平≥100 μg/L者482例,占23.58%。其中血铅水平100～199 μg/L(高铅血症)472例,占23.09%,血铅水平≥200 μg/L（铅中毒）10例,占0.49%。不同年龄组间血铅异常(血铅水平≥100 μg/L)率差异有统计学意义(P<0.01)。男童的血铅异常率为28.99%,高于女童的 21.98% （P<0.01）。不同地区儿童血铅异常率差异亦有统计学意义 (P<0.01)。回归分析显示,男性(OR=1.449, P<0.01)、父亲从事铅暴露职业(OR=1.314, P<0.01)及母亲常用染发剂（OR=1.678,P<0.05）为儿童血铅异常的危险因素。结论：湖南省城镇学龄前儿童血铅异常率较高。该省城镇学龄前儿童血铅异常率与儿童所在地区和年龄有关。男性、父亲从事铅暴露职业及母亲常用染发剂为儿童血铅异常的危险因素。［中国当代儿科杂志,2010,12（8）：645-649］     

The effects of iron deficiency on infants' developmental test performance

Aim : To assess the effects of iron deficiency on developmental test scores in infants. Methods : This prospective, single-blind, controlled clinical intervention study was made on 108 children aged 6–30 mo who applied to our paediatric outpatient clinic. The cases were classified as control ( n = 31, haemoglobin ± 11 g/dl, serum ferritin >12 μg/l, MCV ± 70 fl), non-anaemic iron deficiency (NAID, n = 40, haemoglobin ± 11 g/dl, serum ferritin ± 12 μg/l, MCV ± 70 fl) and iron deficiency anaemia (IDA, n = 37, haemoglobin < 11 g/dl, ferritin ± 12 μg/l, MCV >70 fl) due to their anaemia status. In each group, MCV, haemoglobin and ferritin levels were measured, and Denver Developmental Screening Test (DDST) and Bayley Scales of Infant Development (BSID-I) were administered before and after a 3-mo follow-up. IDA and about half of the NAID subjects were treated with oral iron for 3 mo. Results : Subjects with iron deficiency showed significantly lower developmental test scores both with BSID-I and DDST-II compared to their iron-sufficient peers ( p < 0.05). After 3 mo of iron treatment, lower mental developmental test scores were no longer observed among the IDA and NAID groups whose anaemia and iron deficiency were also corrected. No significant differences were found between control NAID and control IDA groups on DGTT-II results after treatment. The difference in motor and mental developmental scores did not appear to depend on environmental and family factors considered in the analyses.
Conclusion : These findings support the conclusions that iron deficiency may cause lower mental and motor test scores in infants and these adverse effects can be improved by iron therapy.     

Iron status of children with short stature during accelerated growth due to growth hormone treatment

We determined the influence of human growth hormone (hGH) treatment on blood soluble transferrin receptor (sTfR) in 35 children with short stature. Whereas the serum concentration of ferritin decreased from 29.6 μg/1 to 19.7 μg/l, and that of transferrin increased from 2.9g/1 to 3.2g/1 during 6 months ( p < 0.001), only a minimum rise in the sTfR concentration was observed (7.12 ± 0.20mg/1 vs 7.51 ± 0.19mg/l, p = 0.025). The prevalence of anaemia or microcytosis did not increase. Most of the changes in serum ferritin and transferrin concentrations occurred during the first week. The study demonstrates that rapid body growth per se does not affect the sTfR concentration, but it may affect the serum transferrin and ferritin concentrations. Alternatively, GH may have a specific effect on serum ferritin and transferrin concentrations.     

Relationship Between Low-Level Lead Exposure and Neurobehaviors of Preschool Children

目的　探讨低水平铅暴露对儿童神经行为的影响。方法　整群随机抽取某市幼儿园 4～ 6岁 2 11名儿童为研究对象 ,采指端末梢血 2 0 μl,原子吸收石墨炉法测定血铅 ,以血铅水平 10 0 μg/L为界 ,分为高血铅组(≥ 10 0 μg/L)和低血铅组 (<10 0 μg/L) ,采用Achenbach儿童行为量表 (CBCL)及自拟调查表进行问卷调查 ,其结果运用t ,χ2 检验 ,简相关及多元逐步回归等方法进行统计分析。结果　高血铅组外向行为得分及行为异常率(13.2 8± 6 .2 6 ,18.2 6 % )显著高于低血铅组 (9.98± 5 .4 6 ,7.2 9% ) (t =4 .0 6 77,χ2 =5 .4 70 ,均P <0 .0 5 ) ,血铅值与外向行为中多动、攻击、违纪因子分显著正相关 (r =0 .316 4 ,0 .2 82 8,0 .1886 ,P <0 .0 5 ) ,血铅值≥ 15 0 μg/L时 ,行为异常率显著增加 (χ2 =13.6 95 ,P <0 .0 5 )。结论　低水平铅暴露对儿童外向行为具有负性影响。