Search

A case of neonatal Myotonic Dystrophy (MD) is presented. A 35 week old 3570 g baby was born to a mother affected by MD and pregnancy-induced unstable diabetes. Soon after birth, he developed apnea, severe hypoglycemia, hypocalcemia, hypotonia and mild respiratory distress. His clinical course improved during the following days, but persistent episodes of desaturation and/or cyanosis did not subside; hypotonia was mild. A polysomnographic recording showed mixed central and obstructive apnea. DNA testing showed trinucleotide repeat expansion mutations diagnostic of MD. The baby was discharged with home-sleep monitoring and breast-feeding. Recurrent apnea/bradycardia was the main clinical feature in this case of congenital MD, with increased risk of an acute life-threatening event.

During the 1975-1984 period, 93 infants weighing 1500 g or less were transferred to the Magenta Perinatal Center Hospital. The survival rate at discharge was 82.9% for infants transferred in utero and 63.5% for infants transferred postnatally (p less than 0.05). The incidence of major neurological sequelae was 3.1% and 23.3% respectively (p less than 0.02). This experience confirms that the high risk pregnancies should be referred to the Perinatal Center for optimal care of the mother, fetus and newborn infant.

US screening for hip dysplasia was performed on 1421 full-term newborns. The study was aimed at: 1) evaluating US feasibility in an unselected maternity ward population; 2) determining the frequency of the different types of hips, and correlating ours with literature data; 3) evaluating the efficacy of both an early prevention and treatment. All US examinations were performed within the first week of life and the 2842 hips classified according to Graf. At birth, normal hips (Ia, Ib) were 2064 (72.6%) (group I); physiologically immature hips (IIa) were 721 (25.4%) (group II); pathological hips (group III) were: 43 (1.5%) IIc, 8 (0.3%) IId, 6 (0.2%) III. Hips in group B were checked at 3 months: 502 were normal, 51 were type IIb, and 1 was type IId: the latter 52 hips were treated and normalized in the following months. Hips in group C (types IIc, IId, and III = 57 hips) were treated and checked every seventh week until normalization. Our experience confirms US value in the evaluation of hip dysplasia in the newborn. In our opinion, the use of this method should be encouraged, although US screening of all newborns remains controversial on a cost-benefit ratio. Multicentric studies will better define US sensitivity, specificity and reliability. The correlation of our results with literature data was difficult, because study populations are not always homogeneous. As for therapy, we found the plastic splint very effective and easy to use. In 2 cases, Milgram devices were used for a few months.

To evaluate whether the addition of an aminoglycoside might enhance the clinical efficacy of ceftazidime in cystic fibrosis patients with acute exacerbations of chronic Pseudomonas lung infections we carried out a prospective, comparative, randomized blind study with three schedules: ceftazidime vs. ceftazidime plus sisomicin (C/S) vs. piperacillin plus sisomicin, for a total of 60 courses of 14 days of treatment. Each treatment led to clinical and radiologic improvement with marked reduction of signs of acute infection. Statistically there was no significant difference in clinical responses among the schedules. No side effect appeared during treatments with ceftazidime or C/S. Hyperpyrexia was seen in 35% of patients receiving piperacillin. Decrease in Pseudomonas aeruginosa count to less than 10(5) colony-forming units/ml of sputum was achieved in 60% of patients treated with C/S and in 30% of patients who received ceftazidime or piperacillin plus sisomicin (statistically not significant). A transient increase in mean geometric minimal inhibitory concentrations for ceftazidime and piperacillin was observed at the end of the combined therapies. A larger percentage of persistent resistant strains of P. aeruginosa was seen after the combined therapies. We conclude that ceftazidime as monotherapy may be an effective alternative in Pseudomonas lung infections in cystic fibrosis patients. Its clinical efficacy seems not to be enhanced by the addition of an aminoglycoside, although reduction of Pseudomonas in the sputum was better achieved by the combination of C/S.

The pharmacokinetics and clinical efficacy of ceftazidime, a cephalosporin with activity against Pseudomonas aeruginosa, were studied in children with cystic fibrosis. Ceftazidime had high in vitro activity against P. aeruginosa strains isolated from our patients, with a mean MIC90 of 8 micrograms/ml. The first dose of 50 mg/kg IV of ceftazidime achieved serum concentrations of 40.8 +/- 19.7 micrograms/ml at one hour and 3.8 +/- 1 micrograms/ml at four hours after administration (mean values +/- SD). The MIC90 was exceeded by serum concentrations for up to three hours. The elimination of the drug from the blood followed a biexponential decay with an elimination half-life of 60.4 +/- 6.8 min and a total body clearance of 6.0 +/- 3.1 ml/min/kg. Renal clearance of the drug accounted for 75% of the total clearance; these are higher values than those reported for adults. Peak concentrations of ceftazidime in the sputum two hours after a single administration were 4.13 +/- 2.06 micrograms/ml; after seven and 14 days of treatment, sputum concentrations were significantly lower. Eleven children with acute pulmonary exacerbation were treated for 14 days with ceftazidime at a dose of 150 mg/kg/day (12 treatment courses). Significant clinical and radiologic improvements were obtained in nine of 12 patients. In six of 11 cases the P. aeruginosa count decreased by 10(4) CFU/ml. Ceftazidime was well tolerated, and no side effects appeared during treatment.

1. The present study was undertaken to investigate the possibility that central nervous system mono-aminergic pathways may play a role in the control of the renin-angiotensin-aldosterone system in man. 2. Eight normal subjects received in a randomized order placebo, L-dopa (500 mg, orally) and L-dopa (100 mg, orally) plus carbidopa (35 mg, orally) after pretreatment with carbidopa (50 mg every 6 h for four doses). 3. L-Dopa administration elicited a significant fall in plasma renin activity (PRA) (P less than 0.01 at 120, 150 and 180 min) and in plasma aldosterone levels (P less than 0.05 at 90, 120, 150 and 180 min); L-dopa plus carbidopa induced a decrease in PRA (P less than 0.05 at 120 and 150 min, P less than 0.01 at 180 min) and in plasma aldosterone concentration (P less than 0.05 at 30 and 60 min, P less than 0.01 at 90 and 120 min), in comparison with placebo administration; between-drugs analysis revealed no difference in the decreases in PRA and plasma aldosterone levels induced by the two regimens. 4. Since L-dopa, as well as L-dopa plus carbidopa, has been shown to augment catecholamine levels in the brain of various animal species, the present data suggest that in man PRA and plasma aldosterone concentration might be inhibited by increased central nervous system catecholamine levels.

The effects of chronic prazosin treatment (3 mg/day for three weeks) on plasma renin activity (PRA) and plasma aldosterone (PA) levels were evaluated in 12 hypertensive patients, under conditions of metabolic balance. After three weeks of drug administration no significant change occurred in PRA as well as PA levels, with respect to pretreatment values, both in basal conditions and following 2 hours of ambulation. No change was observed in heart rate, while a fall in both systolic (P less than 0.02) and diastolic (P less than 0.05) blood pressure occurred in supine as well as in deambulation-stimulating condition. A mild increase in body weight (P less than 0.05) and a decrease in serum sodium (P less than 0.05) was induced by prazosin treatment. These findings are in keeping with the pharmacologic properties of prazosin, which is a selective blocker of postsynaptic alpha adrenoreceptors and therefore lowers vascular resistance without reflex sympathetic overactivity. The moderate volume expansion after prazosin does not appear to be aldosterone mediated.

The effects of intravenous infusion of the alpha- and beta-adrenoceptor blocking drug labetalol (100 mg over 10 min) on heart rate, blood pressure, and several endocrine and metabolic variables have been evaluated in 12 hypertensive patients (6 men and 6 women). Drug administration was associated with significant lowering of heart rate and systolic and diastolic blood pressure in comparison with a control study performed with saline infusion. Plasma glucose was significantly increased, while no changes were observed in serum-free fatty acids, insulin, C-peptide, and growth hormone levels. Serum prolactin concentration was significantly increased in the whole group, a marked rise occurred in females, while only a trend upward was observed in males. The acute lowering of blood pressure suggests a predominant activity on alpha-adrenoceptors following intravenous labetalol infusion, although the reduction in heart rate is consistent with the beta-adrenoceptor blocking effect of the drug. Although the reason for the increase in plasma glucose is not apparent, it might depend on the rise in norepinephrine levels observed after labetalol. Stimulation of prolactin release by intravenous labetalol is not easily attributable to interference with adrenergic receptors. The mechanism of this action of the drug is presently obscure, although a possible antidopaminergic activity of labetalol might be involved.

In an attempt to evaluate the relative importance of brain and peripheral (i.e., outside the blood-brain barrier) dopamine (DA) receptor stimulation in the regulation of GH release, DA (5 microgram/kg/min infused i.v. for 120 min), L-dopa (500 mg p.o.), L-dopa (100 mg p.o.) plus carbidopa (35 mg p.o.) after pretreatment with carbidopa (50 mg p.o. every 6 h for 1 day), and nomifensine (200 mg p.o.) have been administered to healthy women. Significant elevations in serum GH were induced by all regimens in comparison with a control placebo study, although the effect of DA was only transient in spite of continuing infusion. The between drugs analysis revealed that L-dopa alone was significantly more effective in releasing GH than carbidopa plus L-dopa as well as DA infusion and nomifensine administration. These results suggest that both central nervous system and peripheral mechanisms are involved in dopaminergic stimulation of GH release in man. Since DA does not affect somatotropes directly, increased serum GH levels by DA infusion probably reflect stimulation of median eminence dopaminergic neurons.