Failure to thrive: the prevalence and concurrence of anthropometric criteria in a general infant population.

BACKGROUND: Failure to thrive (FTT) in early childhood is associated with subsequent developmental delay and is recognised to reflect relative undernutrition. Although the concept of FTT is widely used, no consensus exists regarding a specific definition, and it is unclear to what extent different anthropometric definitions concur. OBJECTIVE: To compare the prevalence and concurrence of different anthropometric criteria for FTT and test the sensitivity and positive predictive values of these in detecting children with "significant undernutrition", defined as the combination of slow conditional weight gain and low body mass index (BMI). METHODS: Seven criteria of FTT, including low weight for age, low BMI, low conditional weight gain and Waterlow's criterion for wasting, were applied to a birth cohort of 6090 Danish infants. The criteria were compared in two age groups: 2-6 and 6-11 months of life. RESULTS: 27% of infants met one or more criteria in at least one of the two age groups. The concurrence among the criteria was generally poor, with most children identified by only one criterion. Positive predictive values of different criteria ranged from 1% to 58%. Most single criteria identified either less than half the cases of significant undernutrition (found in 3%) or included far too many, thus having a low positive predictive value. Children with low weight for height tended to be relatively tall. CONCLUSIONS: No single measurement on its own seems to be adequate for identifying nutritional growth delay. Further longitudinal population studies are needed to investigate the discriminating power of different criteria in detecting significant undernutrition and subsequent outcomes.

Absence of high-affinity calreticulin autoantibodies in patients with systemic rheumatic diseases and coeliac disease.

Calreticulin has been reported to be an autoantigen in various autoimmune connective tissue diseases and in coeliac disease. Previous studies have used incubation buffers with low salt and low detergent concentrations (low stringency conditions) with serum albumin or other proteins as a blocking agent. Using these conditions we found a relatively high level of non-specific binding in many sera. Antibodies to proteins that are used as blocking reagents in ELISA (bovine serum albumin (BSA), ovalbumin, skimmed milk powder) are frequently present in sera, and these may cause false-positive results. Moreover, the low isoelectric point of calreticulin and its chaperone properties may give rise to false-positive results under low stringency conditions. We report that the use of a simple buffer without protein (50 mM Tris, pH 7.5, 1% Tween 20, 0.3 M NaCl) removes most of the problems with unwanted binding (high stringency conditions). Using the high stringency conditions, we screened sera from 107 patients with systemic lupus erythematosus, sera from patients with other systemic autoimmune diseases and from children with coeliac disease for the presence of high-affinity calreticulin autoantibodies by immunoblotting and ELISA. None of the sera contained high-affinity calreticulin antibodies. It is concluded that calreticulin is not a common autoantigen in patients with autoimmune connective tissue diseases or coeliac disease.

Interobserver variation in diagnosing coeliac disease. A joint study by Danish and Swedish pathologists.

There is an almost 40-fold difference in incidence rates of symptomatic coeliac disease between Denmark and Sweden. In an attempt to explain this difference, the present study focused on the interobserver agreement when pathologists were assessing small intestinal biopsy specimens from children suspected of suffering from coeliac disease. The study was performed on 90 biopsy specimens from 73 children. Most of the biopsies came from children who turned out not to suffer from coeliac disease after a clinical evaluation including small intestinal biopsy. Using the kappa methodology, the interobserver agreement between two Danish pathologists and one Swedish pathologist, all of whom were experienced, was "moderate" to "substantial" or 0.57-0.75. Kappa indices when the pathologists evaluated selected histological elements were in the interval from 0.24 to 0.67. A comparison of a previous routine diagnostic assessment of the 90 biopsies (14 pathologists) with the results of the experienced pathologists in the present study gave kappa indices of from 0.53 to 0.57. The study could prove no major differences in the histopathological assessment of small intestinal biopsy specimens made by Danish and Swedish pathologists. The difference in clinical presentation of coeliac disease in Denmark and Sweden does not relate to differences in the histopathological assessment of small intestinal biopsies.

[Celiac disease in children on the two sides of the Sound]. / Morbus coeliacus hos børn på de to sider af Oresund.

Of 771 children (381 Swedish and 390 Danish) investigated during 1972-1989 because of suspected coeliac disease (CD), 179 proved to have the disease. Surprisingly only 24 CD patients were Danish whereas 155 were Swedish, despite the very similar ethnic, geographical, and cultural backgrounds of the two populations. The Danish CD children were diagnosed at an older age (mean 5.5 versus 1.5 years). Breastfeeding habits were comparable. The estimated content of gliadin in the officially recommended diets of the two countries in 1987 differed substantially, the Swedish diet containing more than 40 times more gliadin than the Danish (4400 mg versus 100 mg) at the age of eight months, and four times more (3600 mg versus 900 mg) at the age of 12 months. Compared to the Swedish diet, the Danish infant diet contained significantly larger amounts of rye flour, which is low in gluten. The earlier introduction of food items with a high gluten content in the Swedish as compared with the Danish diet could be a possible explanation for the great difference in incidence and symptomatology of CD between the two populations.

Striking differences in the incidence of childhood celiac disease between Denmark and Sweden: a plausible explanation.

Among 771 children (381 Swedish and 390 Danish) investigated between 1972 and 1989 because of suspected celiac disease (CD), 179 proved to have the disease. Surprisingly only 24 CD patients were found among the Danish children, compared with 155 in the Swedish group, despite the close ethnic, geographical, and cultural background of the two populations. The Swedish CD children were diagnosed at an earlier age than the Danish children (mean, 1.5 vs. 5.5 years). The symptoms of the Swedish patients were dominated by failure to thrive (93 vs. 71%), whereas a higher proportion of the Danish CD patients suffered from stomach pain (21 vs. 5%). Breast-feeding habits were comparable. The estimated content of gliadin in the officially recommended diets of the two countries in 1987 differed substantially, the Swedish diet containing more than 40 times more gliadin than the Danish (4,400 vs. 100 mg) at the age of 8 months, and 4 times more (3,600 vs. 900 mg) at the age of 12 months. The Danish infant diet differed significantly from the Swedish in containing a larger amount of the lower gluten-containing rye flour. The earlier introduction of food items with a high gluten content in the Swedish compared with the Danish diet seems to be an obvious explanation for the great difference in incidence and symptomatology of CD between the two populations.

Insulin-like growth factor-I in celiac disease.

To contribute to the description of the physiopathological mechanisms of celiac disease, changes in insulin-like growth factor I (IGF-I) were followed-up in 21 children suspected of suffering from celiac disease. Thirteen children were suffering from celiac disease according to the original criteria of the European Society of Paediatric Gastroenterology and Nutrition. Ten celiac children changing from a gluten-containing to a gluten-free diet presented a significant rise in IGF-I (+1.54 mM per month). In a group of eight celiac children challenged with gluten, seven had a significant decrease in IGF-I (-1.11 mM per month), and five celiac children returning to the gluten-free diet after challenge with gluten had a marked but not significant increase in IGF-I (+1.7 mM per month). Eight children not suffering from celiac disease, but challenged with gluten, had a significant increase in IGF-I (+0.29 mM per month), corresponding to the expected age-dependent increase. The significant changes in IGF-I described under the diagnostic dietetic phases of celiac disease reflect the extent of growth retardation caused by the disease. IGF-I may be a supplementary aid in the diagnosis of celiac disease in describing individual changes under the dietetic phases.

The diagnostic value of the gliadin antibody test in celiac disease in children: a prospective study.

Serum gliadin antibodies (IgA/IgG) were determined in 191 consecutive children (median age, 2.75 years; range, 0.33-15.5 years) admitted for a small-intestinal biopsy on suspicion of celiac disease. The test was a diffusion-in-gel enzyme-linked immunosorbent assay (DIG-ELISA). Of these 191, 14 (7.3%) appeared to have untreated celiac disease. Depending on the choice of cut-off value of the test (combined determination of IgA and IgG), the sensitivity was 86-100%, the specificity was 97-99%, and the positive/negative predictive values were 70-92% and 99-100%, respectively. No variation according to age was found. Gliadin antibodies were determined in 47 children who had well-treated celiac disease. Fourteen of these children were also investigated when challenged with gluten. Gliadin antibodies (IgA or IgG) decreased significantly in 13 of 13 cases when the patients shifted from a gluten-containing diet to a gluten-free one. During the gluten challenge, the IgG and IgA increased in 14 of 14 and 11 of 14 cases, respectively (two patients suffered from IgA deficiency). In eight patients who later appeared to be free of celiac disease, the gliadin antibodies were determined on gluten-free diet and during gluten challenge; no significant differences in gliadin antibodies were found. We conclude that this test is useful in selecting patients with symptoms suggesting celiac disease for a small-intestinal biopsy. The test seems to be of some value in monitoring the effects of a gluten-free diet and during gluten challenge.

Extremely low incidence rates of celiac disease in the Danish population of children.

Incidence rates by birth of celiac disease of 0.09 per 1000 live births were described for the period 1960-88 in the entire Danish population. Broad diagnostic criteria were used in order to prevent the risk of under-diagnosing the disease. The observations support previous local reports from Copenhagen County of low incidence rates by birth of celiac disease. The study presents the lowest incidence rate by birth of celiac disease yet described.

Low incidence rates by birth of symptomatic coeliac disease in a Danish population of children.

Using the original diagnostic criteria of the European Society for Paediatric Gastroenterology and Nutrition for symptomatic coeliac disease in children, we found an average incidence rate by birth of 0.10 per 1000 live births in a demographically homogeneous Danish population over a 15-year period. This incidence rate by birth is the lowest described in an epidemiological study in contrast with rates of 0.33 to 8 per 1000 live births found in other western countries. This difference may be explained by the different diagnostic criteria used for coeliac disease. Another contributing factor may be a late and gradual introduction of gluten-containing cereals into the diet of Danish infants.

The relationship between Apgar score, umbilical artery pH and operative delivery for fetal distress in 2778 infants born at term.

A total of 2778 infants born at term were studied to determine the relationship between Apgar scores after 1 min, umbilical artery pH values, mode of delivery, a diagnosis of fetal distress leading to operative delivery, and sex. Eighty-three percent of the population had normal Apgar scores (greater than or equal to 8) and normal pH values (greater than 7.15) in which 10% were operatively delivered for fetal distress (ODFD). Sixty-one percent of the children with low Apgar scores (less than or equal to 7) had normal pH values, and 74% of the infants with acidosis (pH less than or equal to 7.15) had normal Apgar score. Twenty-four percent of the infants with a low Apgar score and/or acidosis were ODFD (sensitivity). Ninety percent of the infants who had Apgar scores and pH values were not ODFD (specificity). The predictive value (a low Apgar score and/or acidosis) of ODFD was 33%, and the negative predictive value (normal Apgar score and a normal pH) of ODFD was 85%. A significantly higher incidence of ODFD and acidosis was found in boys.

Relationship between infant feeding and infectious illness: a prospective study of infants during the first year of life.

Prior studies investigating the relationship between infant feeding and infectious illnesses in developed countries have provided conflicting data about whether breast-feeding protects against common infectious illnesses early in life. These conflicts may in part be due to the failure to consider the following methodologic issues: (1) collecting data prospectively at frequent intervals for active surveillance of the detection of infections and of feeding practices, (2) specifying what is meant by infectious illnesses and breast-feeding, (3) controlling for confounding variables such as social class or presence of siblings in the household, and (4) applying appropriate analytical strategies to a population in which both feeding and exposure to illness change over time. A total of 500 infants born consecutively in a university-affiliated community hospital in Copenhagen, Denmark, were studied prospectively for the first 12 months of life by means of a detailed, monthly, mailed questionnaire that focused on feeding practices and illnesses (overall response rate, 73%). The percentage of infants who were completely or mostly breast-fed decreased from 88% at 1 month to 20% at 12 months of age. After adjustment for major covariates, no statistically significant relationship was found between the type of infant feeding and the incidence of four categories of infectious illnesses: gastroenteritis, upper respiratory illness, otitis media, and lower respiratory illness. The adjusted incidence density ratio for gastroenteritis was 1.067 (95% confidence interval = 0.982, 1.226) and for upper respiratory illnesses 0.984 (95% confidence interval = 0.883, 1.096).(ABSTRACT TRUNCATED AT 250 WORDS)

Infant feeding patterns during the first year of life in Denmark: factors associated with the discontinuation of breast-feeding.

We prospectively studied 500 infants born consecutively in a university-affiliated community hospital in Copenhagen, Denmark, over the first 12 months of life using a detailed monthly mailed questionnaire (overall response rate = 73%) which focused on feeding practices and illnesses. Seventy-seven percent of respondents breast-fed their infants at 1 month of life compared to 19% at 12 months of life. Analysis of breast-feeding behavior using survival analysis showed that 50% of the mothers who breast-fed since the first month of their infant's life were still breast-feeding at 7 months of life. Also, there was a greater than two-fold increase in the rate of discontinuation of breast-feeding for infants in daycare compared to infants not attending daycare (RR = 2.08, 95% CI = 1.43, 3.01). Discontinuation of breast-feeding was not significantly associated with the number of children in the family or with social class. These results give insight into infant feeding patterns in a developed country and suggest that: (1) breast-feeding is the dominant method of feeding during the infant's first year of life, and (2) the rate of discontinuation of breast-feeding is increased by the entry of these infants into daycare.

Effect of passive smoking on birth-weight.

500 consecutive Danish women who had full-term babies were interviewed on the third or fourth day post partum and asked about smoking in all household members. Exposure to smoking by the mother was found to reduce birth-weight, and indirect or passive exposure to smoking by the father had nearly as large (66%) an effect. On average, birth-weight was reduced by 120 g per pack of cigarettes (or cigar/pipe equivalent) smoked per day by the father. This relation remained statistically significant after controlling for mother's age, parity, alcohol and tobacco consumption during pregnancy, illness during pregnancy, and social class and sex of the baby. The effect of passive smoking was greatest in the lower social classes.

Caliper skinfold measurements in newborns: analysis of a method.

Bilateral skinfold measurements on 10 different sites were performed blindly by 3 investigators in 118 newborns with a mean birth weight from 1,700 to 4,200 g. The caliper method was precise as judged by intra- and interobserver variances. Precision was independent of skinfold thickness, and not related to amount of training. Bilateral measurements of skinfolds over the quadriceps, pectoral and biceps muscles carried the highest precision. Precision was significantly increased by combination of these 3 measurements. There was no significant difference between the precision of these 3 bilateral measurements and 5 selected unilateral sites. For clinical practice, we recommend cumulated measurements of right-sided skinfolds over the quadriceps, pectoral, biceps and triceps muscles and subscapular skinfold.