Frequency of antinuclear antibodies and rheumatoid factor in healthy Turkish children

The frequency of antinuclear antibodies (ANA) and rheumatoid factor (RF) was investigated in 118 apparently healthy children (56 male, 62 female). The mean age was 9.8+/-2.3 years. Antinuclear antibodies (ANA) were detected by indirect immunofluorescence, using a Hep-2 cell substrate. Nephelometry was used to quantify RF in 116 children. Five serum samples (4%, 3M, 2F) were ANA-positive in low titers and all had a speckled pattern. None of the ANA-positive children had other extractable antinuclear antibodies. Rheumatoid factor (RF) was over 25 IU/ml in four children (3%, 3F, 1M). None of these was positive for both antibodies. Our results suggest a similar frequency of ANA in healthy Turkish children even with a Hep-2 cell substrate, when compared to results of other reports. On the other hand, RF was more frequent than in other reported series.     

Serum fructosamine in healthy and diabetic children and adolescents

The determination of fructosamine in serum of healthy newborns, children and adolescents by a new colorimetric method leads to an age-dependent reference range. Correction of the values for total protein yields a median of the results, which is not dependent on age and the upper limit of the reference range is not significantly different from that of healthy adults; this does not hold true for referral to albumin. As the half-life time of glycated serum proteins is shorter (mean 20 days) than that of hemoglobin A1c, fructosamine can provide useful additional informations about the diabetic control of children and adolescents (medium-term record of blood glucose).     

Thyroid antibodies in children and adolescents with thyroid disorders

Thyroid antibodies were determined by three different techniques in the sera of 125 children and adolescents with thyroid disorders and in the sera of 53 short, normal children without thyroid dysfunction. The incidence of antithyroglobulin antibodies in patients with thyroiditis was highest when measured by radioimmunoassay (85%), less than when measured by hemagglutination (24%), and least by antimicrosomal antibodies (7%). No patient who had initially negative serum for RATA subsequently had positive tests during follow-up of five to 24 months, whereas eight of 31 patients with initially negative serum for ATA later developed positive tests. Treatment appeared to have a suppressive effect on RATA, but not on ATA titers, in hypothroid patients with clinical thyroiditis. The incidence of hypothyroidism in the patients with clinical thyroiditis on initial presentation was significant (37%) and suggests that identification of children and adolescents with thyroiditis is important to ensure adequate medical follow-up.     

Persistent antinuclear antibodies in children without identifiable inflammatory rheumatic or autoimmune disease.

One hundred eight children with musculoskeletal pain considered not to be due to an autoimmune or inflammatory disease had an antinuclear antibody (ANA) test performed. Twenty-four of these children were ANA positive on HEp-2 cell substrate at a screening serum dilution of 1:20. A positive ANA test persisted in 21 of 24 of the patients over a mean time period of 38 months (range 1 to 103 months). No sera from any patient at initial evaluation had anti-DNA antibodies by radioimmunoassay or by indirect immunofluorescence on Crithidia luciliae. One patient recently developed elevated anti-DNA (radioimmunoassay) antibodies but still has a negative assay on C luciliae. Four patients had antibodies to core histones by immunoblotting. None had antibodies to Sm, RNP, Ro (SS-A), or La (SS-B) by counterimmunoelectrophoresis. No patient developed an overt inflammatory or autoimmune disease during a mean follow-up period of 61 months (range 13 to 138 months). A child with musculoskeletal pain and a positive test for ANA, but with no clinical evidence at presentation of inflammatory or autoimmune disease, is at low risk of imminently developing such a disease.     

Whole body bone mineral content in healthy children and adolescents

Data from healthy children are needed to evaluate bone mineralisation during childhood. Whole body bone mineral content (BMC) and bone area were examined by dual energy x ray absorptiometry (Hologic 1000/W) in healthy girls (n = 201) and boys (n = 142) aged 5-19 years. Centile curves for bone area for age, BMC for age, bone area for height, and BMC for bone area were constructed using the LMS method. Bone mineral density calculated as BMC/bone area is not useful in children as it is significantly influenced by bone size. Instead, it is proposed that bone mineralisation is assessed in three steps: height for age, bone area for height, and BMC for bone area. These three steps correspond to three different causes of reduced bone mass: short bones, narrow bones, and light bones.     

Whole body bone mineral accretion in healthy children and adolescents

Data on accretion in bone size and bone mineral content (BMC) are needed to evaluate bone mineralisation during childhood. Whole body bone mineral content (BMC) and bone area (BA) were determined by dual energy x ray absorptiometry (Hologic 1000/W) with a one year interval in healthy girls (n = 192) and boys (n = 140) aged 6-19 years. Annual accretion in BMC (ΔBMC (g/year)) and BA (ΔBA (cm²/year)) according to sex and pubertal stages were calculated. ΔBA and ΔBMC were highly significantly associated with pubertal stages in girls and boys. Centile curves for ΔBA and ΔBMC according to sex and age were constructed using the LMS method. Peak ΔBA and ΔBMC values were reached earlier in girls (12.3 and 12.5 years, respectively) than in boys (13.4 and 14.2 years, respectively). The ΔBA peak was dissociated in time from the ΔBMC peak, indicating that increase in bone size occurs before increase in bone mineral content. Assuming that 32.2% of BMC consist of calcium, the median (90th centile) annual bone calcium accretion in pubertal stage III was 220 mg/day (302) and 317 mg/day (386) for girls and boys, respectively. To obtain an average bone calcium accretion, a high calcium absorption is needed during puberty. This may have implications for dietary calcium requirements at this time.     

Prevalence of poliovirus antibodies in healthy children of Ahmedabad

Antibodies against polioviruses were estimated in 258 healthy children upto 3 years of age in Ahmedabad. Fifty per cent of the children were negative for all three poliovirus antibodies before immunisation. Only 7.8 per cent of children had antibodies against all the three types of poliovirus. Prevalence of poliovirus type 1, type 2 and type 3 antibodies were 32.3, 31.8 and 15.5 per cent respectively. In the 3–6 months age group 39.6 per cent children were having poliovirus antibodies against one or more type but the per cent positivity increased in the age group 25–36 months to 78.6 per cent children. There was no difference in the prevalence of polio antibodies between the two sexes. About 92.0 per cent of children upto 3 years of age were lacking in one or more types of poliovirus antibodies in their blood, and would be susceptible for paralytic poliomyelitis if not immunised. Financed by a grant from the Indian Council of Medical Research, New Delhi. This paper was presented in the 28th Annual Conference of Indian Association of Pathologists and Microbiologists heald at Chandigarh in December, 1979.     

Anticardiolipin antibodies in children and adolescents with insulin-dependent diabetes mellitus

Anticardiolipin antibodies were determined in 29 diabetic children and adolescents, aged 3.9–26.8 years, with disease duration from 1 month to 19 years. Anti-islet cell antibodies (ICA-IgG and CF-ICA), anti-insulin antibodies (IAA), antithyroid antibodies and non organ-specifc (NOSA) antibodies were also determined. Patients were grouped according to insulin-dependent diabetes mellitus (IDDM) duration: group I (n=11)<6 months, and group II (n=18)>5 years. Eleven of group II patients showed precocious signs of micro-angiopathic complications. Forty-two age- and sex-matched healthy subjects served as controls. IgG and IgM anticardiolipin antibodies were evaluated by ELISA and their results expressed as arbitrary units (AU). IgG anticardiolipin antibodies were found in 7 patients (24%), while IgM anticardiolipin antibodies were absent in all. IgG anticardiolipin antibodies were more frequent in IDDM patients than in controls (P<0.005) and group I (in 6 out of 11 patients; 54.5%) than in group II (in 1 out of 18 patients; 5.5%) (P<0.025). In five out of six group I patients with IgG anticardiolipin antibodies, ICA-IgG and/or CF-ICA were also found. No correlation was observed between anticardiolipin and other auto-antibodies, micro-angiopatic complications, and HLA typing.     

Organ-specific antibodies in healthy and diabetic children and young adults

160 children and young adults (aged 7-21 years) and 84 diabetics (aged 2-19 years) were screened for thyroglobulin (TgA), thyroid microsomal (MsA), smooth muscle (SMA), parietal cell (PCA), reticulin (RA), glomerular (GIA) and mitochondrial (MA) antibodies. The diabetics were also screened for islet cell antibodies (ICA). The overall incidence of other antibodies than ICA at the lowest serum titre studied was 18.1 percent for healthy children and 30.9% for diabetic children. The elevation in diabetics is significant (p less than 0.01). Females were overrepresented in both groups and had the highest titres of antibodies. The age group 10-14 years was observed to be a special time at which antibody titres became positive. As compared with the controls, diabetics exhibited an increased incidence of MsA (4.4 and 11.9% respectively, p less than 0.001), PCA (5.0 and 10.7% respectively, p less than 0.05) and RA (3.8 and 9.5% respectively, p less than 0.05). The presence of ICA or the duration of diabetes showed no correlation with other autoantibodies. The results indicate that autoantibodies at a low titre are a common phenomenon. Diabetics seem to be susceptible to react against their own tissue, which is probably associated with their increased frequency of autoimmune diseases.     

Neonatal antinuclear antibodies and the lupus syndrome

Neonatal lupus syndrome can be considered as being associated with pregnancy in women with lupus. Two antinomic cases are reported: a pregnancy in a woman presenting with Sj?gren's syndrome, bearing a child with neonatal lupus syndrome (atrioventricular block and antinuclear antibodies) and a pregnancy in a woman presenting with lupus and giving birth to a normal child with antinuclear antibodies. These 2 case reports allow us to speculate on the pathophysiology of neonatal lupus syndromes in which the type of antinuclear antibodies seems to play a major role.     

Blood pressure and cardiovascular autonomic function in healthy children and adolescents

OBJECTIVES: To investigate the relationship between blood pressure levels and cardiovascular autonomic function in adolescents and preadolescents. STUDY DESIGN: We measured variability of beat-to-beat arterial pressure and R-R intervals using power spectral analysis in 56 adolescents (aged 13-16 years; mean age, 9.0 +/- 1.4 years) and 71 preadolescents (6-12 years; mean age, 13.5 +/- 1.1 years) in the supine and standing positions. RESULTS: Adolescents had higher levels of systolic arterial pressure and lower high-frequency power of RR intervals than preadolescents. Correlation between the basal level of arterial pressure and autonomic function was observed in adolescents but not in preadolescents. In adolescents, multivariate analysis indicated that the basal level of arterial pressure was inversely related with the high-frequency power of RR intervals and positively with the ratio of low-frequency and high-frequency power. No significant relation was found in preadolescents. During standing, adolescents had a more marked increase in diastolic arterial pressure, heart rate, low frequency of R-R intervals, and low frequency of arterial pressure compared with those of preadolescents. Changes in diastolic pressure showed a significant negative correlation with changes in high frequency of R-R intervals. CONCLUSION: Cardiovascular autonomic function plays an important role in increasing blood pressure levels associated with increased modulation of vagal tone of the heart after puberty but does not in the preadolescent.     

Whole body bone mineral accretion in healthy children and adolescents.

Data on accretion in bone size and bone mineral content (BMC) are needed to evaluate bone mineralisation during childhood. Whole body bone mineral content (BMC) and bone area (BA) were determined by dual energy x ray absorptiometry (Hologic 1000/W) with a one year interval in healthy girls (n = 192) and boys (n = 140) aged 6-19 years. Annual accretion in BMC (DeltaBMC (g/year)) and BA (DeltaBA (cm2/year)) according to sex and pubertal stages were calculated. DeltaBA and DeltaBMC were highly significantly associated with pubertal stages in girls and boys. Centile curves for DeltaBA and DeltaBMC according to sex and age were constructed using the LMS method. Peak DeltaBA and DeltaBMC values were reached earlier in girls (12.3 and 12.5 years, respectively) than in boys (13.4 and 14. 2 years, respectively). The DeltaBA peak was dissociated in time from the DeltaBMC peak, indicating that increase in bone size occurs before increase in bone mineral content. Assuming that 32.2% of BMC consist of calcium, the median (90th centile) annual bone calcium accretion in pubertal stage III was 220 mg/day (302) and 317 mg/day (386) for girls and boys, respectively. To obtain an average bone calcium accretion, a high calcium absorption is needed during puberty. This may have implications for dietary calcium requirements at this time.     

Lymphocyte subsets identified by monoclonal antibodies in healthy children

The distributions of lymphocyte subsets and monocytes in the peripheral blood mononuclear leukocytes of 72 normal children from 2 months to 13 5/12 yr were examined using quantitative immunofluorescence analysis with monoclonal antibodies. Distinct decreases with age were found in the total leukocyte counts, the percentages and the absolute numbers of peripheral blood mononuclear leukocytes. The percentages of Leu-2a+ cells, Leu-7+ cells, and Leu-M3+ cells significantly increased with age, whereas the percentages of Leu-3a+ cells, Leu-4+ cells, and 2H7+ cells significantly decreased with age. As a result, ratios of Leu-3a+/Leu-2a+ decreased with age. No prominent differences with age were found in the proportions of Leu-10+ cells and HLA-DR+ cells.     

Body fat reference curves for healthy Turkish children and adolescents

Childhood obesity is a major worldwide health problem. In addition to body mass index (BMI), body fat percentiles may be used to predict future cardiovascular and metabolic health risks. The aim of this study is to define new age- and gender-specific body fat centiles for Turkish children and adolescents. A total of 4,076 (2,276 girls, 1,800 boys) children and adolescents aged 6–18 years were recruited for this study. Total body fat was measured by a bioelectrical impedance noninvasive method. Body fat percentiles were produced by the LMS method. The body fat percentile curves of boys appear to rise from age 6 to 12 years and then slope downwards to age 15 years and then flatten off. The body fat % percentiles of girls increased until 14 years of age through 75th to 97th percentiles and then slope downwards, but through the third to 50th percentiles, they showed a downward slope after 14 years old. Conclusions: Since BMI may not always reflect body fat content, direct assessment of adiposity by a practical method would be significantly useful for clinical decisions. Therefore, this study provides normative data for body fat percentage in healthy Turkish children and adolescents. To this goal we used a practical and clinically applicable method. These references can be useful for evaluation of overweight and obesity.