A Case of Hypothyroidism Probably Caused by 131I Transmitted in Maternal Milk

When the patient was 1–2 years of age, the mother was treated with a total dose of 19 mCi ¹³¹I for hyperthyroidism. Lactation continued during treatment. The patient became hypothyroid 2–3 years later, characterized by a markedly shortened stature. Treatment with desicated thyroid resulted in a euthyroid status and improvement of the short stature.     

Urinary Excretion of Phosphate in Normal Children

In 55 normal children on a normal diet, the phosphate and creatinine were estimated in a fasting 2-hour urine collection and in a simultaneous blood sample. In comparison with adults, a high serum phosphate and relatively decreased phosphaturia were found, both of which tended to adult values with the advent of puberty. A correlation between the serum phosphate and the urine phosphate/creatinine ratio (r = + 0·42, p <0·002) was found. The phosphate excretion index was lower in mid-childhood than in adulthood.The interpretation of any expression of phosphaturia in childhood requires its own age-specific normal range.     

Urinary C-peptide Excretion in Obese and Anorectic Children

ABSTRACT. To assess the total insulin secretion in children in different nutritional states we have analysed the 24 h urinary C-peptide excretion in 32 obese children (16 boys and 16 girls) 8–15 years of age as well as in 7 girls with anorexia nervosa 11–16 years of age. Obese children had a median urinary C-peptide excretion rate of 0.27 nmol/kg/24 h, which was not different from that of a group of normal-weight children. In the group of anorectic girls, on the other hand, the median value 0.47 nmol/kg/24 h was significantly ( p <0.05) higher than for normal-weight girls of the same age (median = 0.26 nmol/kg/24 h). These results indicate that in obese children insulin secretion, measured as the 24 h urinary C-peptide excretion per kg body weight, is the same as in normal-weight children. Total insulin secretion is consequently increased. In anorexia nervosa, on the other hand, the higher C-peptide excretion per kg body weight compared with normal-weight children, indicates that insulin secretion is increased in relation to body weight.     

Concentrations of LTB4, LTC4, LTD4 and LTE4 in bronchiolitis due to respiratory syncytial virus

Fifty-five infants with bronchiolitis due to respiratory syncytial virus were evaluated for the presence of leukotriene B₄, C₄, D₄ and E₄ in nasopharyngeal secretions. An attempt was made to correlate concentrations of leukotrienes to arterial oxygen tension. Forty participants received conventional therapy consisting primarily of aerosolized albuterol and occasional aminophylline therapy. The other 15 individuals received ribavirin therapy in addition to conventional therapy, and leukotriene concentrations were compared among individuals in these groups. RSV infection was documented by standard methods, and leukotrienes were measured by reverse-phase high pressure liquid chromatography. The leukotriene detected most commonly was LTC₄ (up to 83% of subjects); LTD₄ and LTB₄ were present in approximately 30% of individuals. The mean partial pressure of oxygen was found to be lower in those individuals with detectable LTB₄ than in those without detectable LTB₄ (p < 0.025), and an overall inverse correlation of LTB₄ concentrations with initial pO₂ values was observed (r = 0.318, p < 0.05). The presence and quantity of other leukotrienes did not correlate with the severity of illness. During the first week of illness, the concentration of leukotrienes declined sharply in ribavirin recipients. Individuals receiving conventional therapy during the same time interval exhibited stable or increasing leukotriene concentrations. These observations suggest that LTB₄ may be important in the pathogenesis of bronchiolitis, and that ribavirin therapy may inhibit leukotriene release in the respiratory tract.     

Altered Na+-K+ ATPase activity in uraemic adolescents

The Na⁺-K⁺ ATPase enzyme plays an essential role in the regulation of cell composition and volume. Enzyme activity itself is regulated by substrate availability and several hormones. In adult uraemic patients red blood cell Na⁺-K⁺ ATPase activity is decreased. However, it is unknown if children with uraemia exhibit the same phenomenon. Therefore, in the present study we examined whether endogenous digoxin-like factors (EDLF) and physicochemical membrane properties play a role in the regulation of erythrocyte Na⁺-K⁺ ATPase activity in uraemic children and adolescents. Healthy age-matched children were used as controls. Enzyme activity was measured in detergent-pretreated red blood cells and erythrocyte ghosts. Na⁺-K⁺ ATPase activity (2204 ± 538nmol Pi ml erythrocyte^?1 h^?1 in detergent pretreated erythrocytes; 204 ± 56 nmol Pi mg protein^?1 h^?1 in ghosts) in adolescents with uraemia was lower compared to controls (3245 ± 362 nmol Pi ml erythrocyte ¹ h^?1; 266 ± 37 nmol Pi mg protein^?1 h^?1, p < 0.001, p < 0.05, respectively). Plasma levels of EDLF were elevated in uraemic patients (0.30 ± 0.05 versus 0.21 ±0.04 ng ml^?1, p < 0.01). Furthermore, the membrane lipid component was decreased in patients with uraemia, while the cholesterol/phospholipid ratio and membrane fluidity were similar in both groups. No correlation was found between the decrease in Na⁺-K⁺ ATPase and the increase in EDLF concentration and altered membrane lipid components. Our results demonstrate, that similar to the findings of adults, the activity of Na⁺-K⁺ ATPase is diminished in uraemic adolescent patients, and that uraemia-associated elevation in EDLF and altered membrane components do not play a role in the down-regulation of Na⁺-K⁺ ATPase. Therefore other factors (presence of other inhibitors and/or reduced number of enzyme molecules) should contribute to the lower activity of the Na⁺-K⁺ pump.