Enzymuria in neonates receiving continuous intravenous infusion of gentamicin.

Urinary excretion of the tubular enzymes NAG and AAP was investigated during gentamicin treatment of 105 newborn infants. The values found for NAG and AAP show a significant positive correlation. The urinary excretion of NAG was on the average 92% higher during gentamicin treatment as compared with non-treatment periods in the same newborn infant (33 infants). The same tendency applied to AAP. Newborn infants receiving continuous intravenous infusion of gentamicin were not found to be at greater risk of nephrotoxicity than those receiving intermittent gentamicin treatment, using NAG and AAP as an index of nephrotoxicity. The changes in NAg and AAP within treatment periods were studied. During gentamicin treatment an insignificant average increase in the urinary excretion of NAG occurred, whereas a significant decrease was found during non-treatment periods. A significant negative correlation was found between urinary excretion of NAG and birth weight/gestational age. The long-term effect of the higher excretion of NAG and AAP in newborn and adult patients during aminoglycoside treatment is unknown.

Aminophylline versus caffeine citrate for apnea and bradycardia prophylaxis in premature neonates.

We investigated the efficacy and adverse effects of aminophylline and caffeine citrate in 180 premature neonates for 10 days and nights. Aminophylline (n = 98) and caffeine citrate (n = 82) were equally effective in preventing apnea and bradycardia. The caffeine citrate group had a lower median heart rate on day 3, fewer neonates with tachycardia and a smaller amount of gastric aspirate on day 7. The need for mononasal continuous positive airway pressure and respirator therapy was similar in both groups. We conclude that caffeine citrate is the drug of choice for apnea and bradycardia prophylaxis in premature neonates with a gestational age < or = 33 full weeks.

Renovascular hypertension after kidney transplantation.

The development of hypertension after kidney transplantation was examined in a consecutive series of 83 transplantations (79 patients) with a graft survival of more than 30 days. After transplantation, 50% of the normotensive recipients developed mild or severe hypertension, while 74% of the hypertensive recipients remained hypertensive. Stenosis of the graft artery with a narrowing of the diameter of more than 50% was found in 13 patients and in 3 patients a minor or peripheral stenosis was found. Significantly more stenoses were seen in the presence of two donor arteries, whereas no other etiological factors could be shown. In arterial stenosis, severe hypertension was established within a few months after transplantation, but in spite of satisfactory controlled blood pressure and good graft function, hypertensive crises could arise. It is therefore concluded that arteriography and renin analysis should be considered in all cases of severe hypertension, and surgical correction should be considered when arterial stenosis is present.

Cerebral blood flow and left ventricular output in spontaneously breathing, newborn preterm infants treated with caffeine or aminophylline.

Aminophylline and caffeine are commonly used for prophylaxis of apnea in premature infants. Previous studies have indicated different effects of the drugs on cerebral circulation. Therefore, we have compared the acute effects of bolus administration of caffeine citrate or aminophylline on left ventricular output, heart rate, blood pressure and global cerebral blood flow. The study group consisted of 33 newborn, spontaneously breathing, preterm infants randomly assigned to receive either aminophylline 5 mg/kg (n = 19) or caffeine citrate 20 mg/kg (n = 14). Two hours after iv drug administration, global cerebral blood flow measured by the Xe-clearance technique was significantly lower after aminophylline than after caffeine (mean (SD)): 13.2 (+2.9/-2.3) versus 17.2 (+7.1/-5.1) ml/100 g/min) (p = 0.01). There were no other statistically significant differences in circulatory or ventilatory parameters between the groups. Further studies are needed to clarify the clinical relevance of these results.

Micturition cystourethrography using X-ray or scintigraphy in children with reflux.

Thirty children with first time urinary tract infection were investigated for vesicoureteral reflux after bladder catheterization. Micturition cystourethrography with X-ray was compared to scintigraphy because scintigraphy gives less than 10% radiation dose by fluoroscopy. Reflux to the renal pelvis was observed more frequently with scintigraphy, otherwise the nosographic sensitivity and the predictive value of a negative test were about the same (0.90). Scintigraphy is therefore recommended for routine control of reflux in children.

Nitrofurantoin versus trimethoprim prophylaxis in recurrent urinary tract infection in children. A randomized, double-blind study.

The efficiency of nitrofurantoin and trimethoprim prophylaxis in preventing recurrent urinary tract infections (UTI) was compared by means of actuarial percentage recurrence-free curves in a randomized, double blind study in 130 children (126 girls, 4 boys) aged 1 to 14 years (mean 7.5). The children received the antibiotics for 6 months. Nitrofurantoin proved to be the most efficient prophylactic drug in patients with abnormal urography and/or reflux (n = 60) as evaluated by actuarial percentage recurrence-free analysis (p = 0.0025). However, no differences was found in patients without urinary tract abnormalities. Nitrofurantoin prophylaxis altered neither the pattern of resistance nor the bacteriological constellation, while patients receiving trimethoprim prophylaxis had 76% trimethoprim resistant bacteria during prophylaxis, compared with 8% before (p less than 0.0001) and 17% after (p less than 0.0001) prophylaxis. The percentage of recurrences due to E. coli (70-80%) was unaffected by trimethoprim prophylaxis, but the proportion due to trimethoprim resistant E. coli was significantly higher during prophylaxis (65%) than before (6%, p less than 0.0001) and after (11%, p less than 0.001). The percentage of Staphylococcus epidermidis UTI was significantly higher during trimethoprim prophylaxis (27%) than before (2%, p less than 0.0003). Following prophylaxis there was no difference in the actuarial percentage recurrence-free curves of the two regimens. Side effects occurred more frequently in the nitrofurantoin group (37%) than in the trimethoprim group (21%) (p = 0.05). The majority of side effects in the nitrofurantoin group derived from gastrointestinal symptoms. In conclusion, nitrofurantoin is recommended as the first choice prophylactic treatment of children with recurrent UTI and urinary tract abnormalities.