Intussusception in the premature infant

Intussusception is uncommon in the neonatal period; only a few cases have been reported in premature infants. Two such cases are described. The infants presented with abdominal distention and vomiting followed by rectal bleeding. Confusion with the diagnosis of necrotizing enterocolitis (NEC) led to a delay in operation. Pathological leading points were present in both patients. Early operation is recommended for persistent intestinal obstruction in premature infants with an atypical picture of NEC or meconium disease not relieved by meglumine diatrizoate (Gastrografin) enema. Offprint requests to: O. Zamir at the above address     

Intraventricular hemorrhage in the premature infant

Periventricular-intraventricular hemorrhage is the most important adverse neurologic event of the newborn period. It is very common and can be very severe. Such hemorrhage begins in the germinal matrix but may spread into and throughout the ventricular system. It may be accompanied by hemorrhage within the brin parenchyma. The pathogenesis of periventricular-intraventricular hemorrhage is still imperfectly understood, but relates to the anatomy and physiology of the developing cerebral vasculature and to the biophysical and biochemical environment in which that development proceeds. Periventricular-intraventricular hemorrhage may be marked by a catastrophic clinical deterioration, but is more commonly accompanied by a saltatory progression that may be difficult to detect clinically. Both concomitant neonatal disease and therapeutic intervention for such disease have been implicated in the initiation and exacerbation of periventricular-intraventricular hemorrhage. Real-time ultrasound scanning with portable instruments is now the best procedure for identifying this lesion and for assessing its sequelae. Prognosis relates principally to the severity of the lesion. Early management must be particularly directed to the maintenance of cerebral perfusion. Later management is predominantly the therapy of posthemorrhagic hydrocephalus. There is no currently available therapeutic modality that will prevent progressive posthemorrhagic hydrocephalus.     

Brain ultrasonography in the premature infant

Brain ultrasonography plays a central role in the detection and management of neonatal disease in the preterm infant. Although morphological study, using high-frequency transducers, remains the cornerstone of imaging, pulsed and colour Doppler scans provide additional information and improve the diagnostic and prognostic accuracy of ultrasonography. Particular features of normal brain US in the extremely preterm infant are reported. Cerebral haemorrhage and its different patterns (intraventricular haemorrhage and periventricular hemorrhagic infarction) are described. The value of Doppler techniques is emphasized, e.g. demonstration of coloured signal within the aqueduct of Sylvius, visualization of patency of the terminal veins, demonstration of Doppler spectrum fluctuations, recognition of low blood flow, and the detection of vasodilatation. The sonographic diagnosis of periventricular leucomalacia and its difficulties are documented. Some uncommon brain lesions of the premature infant are illustrated, e.g. gangliothalamic ischaemic damage, cortical necrosis, focal infarcts, etc. The importance of repeating the US examinations until near term is highlighted.     

Molybdenum balance studies in premature male infants

Despite the fact that the trace element molybdenum (Mo) is essential, there is insufficient knowledge about the demands in infancy. Mo balances were therefore assessed under consideration of formula Mo concentrations ranging from 0.125 to 2.704 μmol/l. Sixteen premature male infants participated in the investigation. Their birth weights were between 1500 and 1990 g, the median (range) gestational age was 34 (32–36) weeks and the post-conceptual age at the time of study 37.4 (34.1–40.6) weeks. Twenty-four balance studies were performed and the materials analysed by atomic absorption spectroscopy. Infants with a “low” Mo intake received 0.024 (0.020–0.035) μmol/kg per day, had a urinary excretion of 0.02 (0.008–0.045) and a retention of 0.0006 (−0.03 to 0.008) μmol/kg per day. Infants with a “high” intake received 0.284 (0.227–0.487) μmol/kg per day, had a urinary excretion of 0.243 (0.118–0.378) and a retention of 0.022 (−71.1 to 141.44) μmol/kg per day. Since the median urinary excretion exceeded 60% of the Mo intake at low and high intakes, sufficient resorption but minimal retention was assessed at low intakes of Mo. Conclusion In view of the limited knowledge of long-term exposure to an elevated molybdenum intake and the substantial retention observed at higher intakes, upper limits should be set for molybdenum concentrations in preterm infant formulas. Received: 22 February 2000 and in revised form 13 July 2000 and 23 August 2000 Accepted: 25 August 2000     

Peripheral retinal lesions in the premature infant

The periphery of the retina was examined with the use of contact lenses at the age of 5 years in children who were born prematurely and weighed less than 1,500 g at birth. In this retrospective series 65% of the children were found to have lesions similar to the classical findings in retrolental fibroplasia although only to a minor degree. Low oxygen levels with a short duration of the exposure cannot completely prevent these sequalae. This retinopathy which is limited to the periphery, may account for the frequency and severity of myopia in children who were premature. Later in childhood and more rarely retinal detachment or tears may occur which cause severe visual impairment.     

Furosemide-related renal calcifications in the premature infant

Low birthweight infants treated with chronic furosemide therapy are at risk for the development of intrarenal calcifications. A prospective longitudinal renal ultrasound investigation was conducted to study the correlation of diuretic therapy, clinical course and ultrasonographic findings. Of 117 premature infants studied ultrasonographically upon discharge from the hospital, 20 had intrarenal calcifications. Eight patients at age 16.3±2.6 months had sonographic resolution of renal calcifications, 6.6±1.1 months after furosemide therapy had been discontinued. Of the 12 patients with persistent calcifications, 4 died from severe pulmonary disease and autopsy in 3 of them confirmed the ultrasonographic diagnosis. All 12 children but 2 continued to receive furosemide for their chronic lung disease demonstrating significant association between chronic use of loop diuretics and persistance fo the renal calcifications (p<0.001). Two patients required nephrolithotomy and 4 suffered from recurrent urinary tract infections. In 4 patients, 5 kidneys were of small size and in 2 bilateral collecting system dilation was noted. We conclude that discontinuation of furosemide therapy is associated with resolution of the renal calcifications. On the other hand, continued treatment with furosemide is associated with high renal morbidity which indicates ongoing clinical and ultrasonographic follow-up.