Measurement of serum free IGF-I in diagnosis of growth hormone deficiency.

Serum levels of total insulin-like growth factor-I (IGF-I) are growth hormone (GH) dependent and can be used as the screening tool for GH deficient status. However, most of them are bound to IGF-binding proteins, leaving less than 1 per cent in the free or unbound forms which represent the active biological fractions. Serum free IGF-I levels were measured by radioimmunoassay (IRMA) in 48 short children with various conditions. We found that the means +/- SEM of free IGF-I in children with panhypopituitarism (PAN) and complete growth hormone deficiencies (cGHD) were significantly lower than those in sex and age matched normal children (0.02 +/- 0.01 vs 2.01 +/- 0.7 ng/ml, p = 0.0006 and 0.42 +/- 0.18 vs 1.72 +/- 0.27 ng/ml, p = 0.0007 respectively) but not in children with partial growth hormone deficiencies (pGHD) (0.91 +/- 0.3 vs 1.97 +/- 0.4 ng/ml, p = 0.27) and idiopathic short stature (ISS) (0.94 +/- 0.3 vs 1.95 +/- 0.6 ng/ml, p = 0.13). However, when we classified the pGHD children into 2 groups according to IGFBP-3 SDS for normal Thai children, we found that the mean of free IGF-I levels in pGHD children with IGFBP-3 SDS < or = -1.3 was significantly lower than that of the controls. (0.68 +/- 0.55 vs 2.66 +/- 0.71 ng/ml, p = 0.04) In conclusion, the measurement of free IGF-I level can be used to evaluate the GH status of short children and might be used as a guide when starting treatment.

Type 1 diabetes in Thai children aged 0-14 years.

Fifty-nine patients were diagnosed with diabetes in the ten years from 1987 to 1996 in the Division of Endocrinology and Metabolism, Department of Pediatrics, Faculty of Medicine Siriraj Hospital, Bangkok, Thailand. All patients were less than fifteen years old. Fifty-five patients (93.3%) were type 1 diabetes, three (5%) were type 2 diabetes and MODY, and one (1.7%) was diabetes secondary to beta thalassemia major. Patients with type 2 diabetes, MODY, and secondary diabetes were excluded from this study, and fifty-five patients with type 1 diabetes were analysed. The aims of this study were to determine some of the general characteristics of Thai childhood type 1 diabetes and to see whether a seasonal variation is present. The results showed a female to male ratio of 1.39:1. The peak age at diagnosis was from 9 to 12 years. Seventy-seven per cent had diabetic ketoacidosis at the time of diagnosis. The majority of patients (93.9%) had a BMI of less than 20 kg/m2. A family history of diabetes was reported in 38 per cent but only 2 per cent were type 1 diabetes. We found a high prevalence of patients in the summer and winter seasons (35-48% and 37-50% respectively) and a lower prevalence in the rainy season (14.8-15%). These results are different from a previously reported study in 1984-1985 which found no differences in summer, winter, and rainy seasons. Further research study into Thai childhood type 1 diabetes is needed, especially the influence of seasonal factors, the incidence of the disease, and the significance of family history.

Serum IGF-I and IGFBP-3 levels for normal Thai children and their usefulness in clinical practice.

Serum IGF-I and IGFBP-3 levels are growth hormone (GH) dependent and reflect the endogenous GH secretion. Two hundred and forty-four healthy children were evaluated for serum IGF-I and IGFBP-3 levels and then the age-defined normal values for Thai children were constructed. The results showed that the serum IGF-I and IGFBP-3 levels were age dependent, gradually increased from birth and reached the peak values around the age of 14-16 years. In addition, we studied the IGF-I and IGFBP-3 values in 28 GH deficient children and 26 normal variant short stature (NVSS) by using our normal constructed values as the reference. To minimize the influence of age, both IGF-I and IGFBP-3 values were transformed to standard deviation score (SDS). In clinical practice, we recommend using the IGF-I SDS and IGFBP-3 SDS of -1 and -1.3 respectively as a cut-off point to discriminate between GH deficiency and NVSS to avoid risky GH provocative tests and unnecessary GH replacement with the sensitivity of 71 per cent and the specificity of 92 per cent.

Serum IGF-I and IGFBP-3 levels by immunoeadiometric assay (IRMA) in diagnosis of growth hormone deficiency.

The anabolic actions of growth hormone (GH) are mediated by insulin-like growth factor-I (IGF-I) which circulates in blood bound with high affinity to specific carrier proteins, IGF-binding proteins (IGFBP) especially IGFBP-3. Serum levels of IGF-I and IGFBP-3 reflect 24-hour growth hormone status. We divided 44 children into 4 groups depending on growth hormone status. Group I (n=9), complete growth hormone deficiency (GHD). Group II (n=9), partial GHD. Group III (n=12), idiopathic short stature Group IV (n=14), normal children. Measurement of serum IGF-I and IGFBP-3 was performed by immunoradiometric assay (IRMA). The results showed the serum IGF-I and IGFBP-3 levels in group I were 123.1 + 106.8 ng/ml and 1825.1+ 966.6 ng/ml respectively which were significantly different from the levels in group 4, IGFI=270.7+ 139.4 ng/ml (p=0.025) IGFBP-3 = 2702.7+ 500.4 ng/ml (p=0.009) but not in group 2 and 3. In conclusion serum IGF-I and IGFBP-3 levels were proved to by useful for diagnosis of complete GHD.

The correlation between osmolality and specific gravity of parenteral nutrition solution.

The correlation between osmolality and specific gravity of parenteral nutrition solutions containing various concentrations of amino acid and glucose were studied. There is good correlation between osmolality and specific gravity up to 1,000 mOsmol/kg H2O and 1.050, respectively. There are strong correlations between osmolality and amino acid concentration at each concentration of glucose. An equation which can be applied for quick calculation of osmolality of the solution from amino acid and glucose concentrations is: Osmolality (mOsmol/kg H2O) = 74.36 G + 163.91 A - 36.56. The results of this study can be adopted by all physicians for quick assessment of the osmolality of the PNS before administration to patients.

Gastric emptying pattern in Thai infants.

Gastric emptying of milk from the stomach of Thai infants shows a biphasic pattern. At 40 minutes the amount of stomach contents is more than at 20 minutes. At 100 minutes, only 16 per cent of the initial amount was recovered. The results of our study can be used as a standard reference for further study in infants with other diseases.

Effect of recombinant DNA human growth hormone in Thai children with growth hormone deficiency.

We conclude that recombinant DNA methionine-free hGH treatment of GH-deficient Thai children is very effective in the first year of treatment. No patients reported any side effects or resistance to treatment.

An estimation of volume of fluid by using Polyethylene Glycols (PEG) as a marker: An in vitro study.

Polyethylene glycols are non-digestable and non-ansorbable substances, being used extensively in studies of the DI tracts. When amount and concentration of PEGs are known, then the volume of fluid could be estimated. From the in vitro study, we measured the substances at 5 different concentrations. The results showed that the volumes of fluid estimated were about 7 percent higher than the actual. From this study we could conclude that the accuracy of the measurement is within 7 percent of the estimated volume, which will be used as a reference for further related study.