Effects of arginine treatment on nutrition, growth and urea cycle function in seven Japanese boys with late-onset ornithine transcarbamylase deficiency.

BACKGROUND: The aim of this study was to investigate the effects of arginine on nutrition, growth and urea cycle function in boys with late-onset ornithine transcarbamylase deficiency (OTCD). Seven Japanese boys with late-onset OTCD enrolled in this study resumed arginine treatment after the cessation of this therapy for a few years. Clinical presentations such as vomiting and unconsciousness, plasma amino acids and urinary orotate excretion were followed chronologically to evaluate urea cycle function and protein synthesis with and without this therapy. In addition to height and body weight, blood levels of proteins, lipids, growth hormone (GH), insulin-like growth factor-I (IGF-I) and IGF-binding protein -3 (IGFBP-3) were monitored. RESULTS: The frequency of hyperammonemic attacks and urinary orotate excretion decreased significantly following the resumption of arginine treatment. Despite showing no marked change in body weight, height increased gradually. Extremely low plasma arginine increased to normal levels, while plasma glutamine and alanine levels decreased considerably. Except for a slight increase in high-density lipoprotein cholesterol level, blood levels of markers for nutrition did not change. In contrast, low serum IGF-I and IGFBP-3 levels increased to age-matched control levels, and normal urinary GH secretion became greater than the level observed in the controls. CONCLUSION: Arginine treatment is able to reduces attacks of hyperammonemia in boys with late-onset OTCD and to increase their growth.

[Metabolic, hormonal and nutritional effects of long-term theophylline therapy in preterm infants: a case-control study]. / Effetti metabolici, ormonali e nutrizionali della terapia prolungata con teofillina nei nati pretermine: uno studio caso-controllo.

Theophylline is widely used in preterm newborns for the prevention of idiopathic apnoeas, but few controlled studies have evaluated its effects on the nutritional and hormonal status of the infant. For this reason we have studied the effect of long term theophylline administration on 16 laboratory parameters concerning the metabolism of proteins, glucose, lipids, hormones and the glomerular function (blood: hemoglobin, glucose, albumin, prealbumin, urea nitrogen, creatinine, cholesterol, triglycerides, apolipoproteins A-I and B-100, IGF-I, IGFBP-3; urine: urea nitrogen, creatinine, C-peptide, GH). A case-control study was performed on 18 healthy preterm infants who were receiving oral theophylline for the prevention of idiopathic apnoeas. The mean duration of therapy at the moment of the balance study was 31 days (SD 12, range 12-51), the mean daily dose was 4.2 mg/kg (SD 1.0), the plasma range of theophylline concentration was 5 to 15 mg/l. As controls, 18 healthy preterm infants of comparable post-conceptional age, body weight and calories/protein intake at the moment of the study, were selected if they had been never treated with theophylline. No statistically significant differences were found between the two groups for the growth velocity or any of the parameters studied. The only notable exception was hemoglobin, which was significantly lower in theophylline treated infants (mean values 10.5 vs 12.7 g/dl, p 0.005 at t test). In synthesis, long term theophylline treatment in preterm infants seems to be safe from the point of view of growth, glucose, protein and lipid metabolism, hormones and glomerular function, but further studies are needed on the effects of theophylline on neonatal erythropoiesis.

Early detection of nephrotoxic effects in thalassemic patients receiving desferrioxamine therapy.

Nineteen transfusion-dependent beta-thalassemia major patients were included in the study. Six of these patients underwent chelation therapy with desferrioxamine by subcutaneous infusion (50 mg/kg/12 hr) and 13 received intravenous infusion (50 mg/kg/6 hr or 100 mg/kg/24 hr). BUN, creatinine, creatinine clearance, beta 2-microglobulin, urinary beta 2-microglobulin and urinary growth hormone excretion were evaluated during desferrioxamine treatment. Thirteen out of nineteen patients presented tubular damage indicated by increased excretion of urinary beta 2-microglobulin. 85% (11 of 13) of these patients showed more serious tubular damage, as demonstrated by concurrent increased urinary growth hormone excretion. Moreover, a positive correlation between urinary growth hormone excretion and urinary beta 2-microglobulin was observed (P < 0.05).