Elizabeth James

Heparin-induced thrombocytopenia in the newborn

This pilot study was initiated to determine whether heparin-induced thrombocytopenia occurs in the newborn and whether thromboembolic complications in the newborn could be related to heparin-induced thrombocytopenia. Thirty-four infants in whom thrombocytopenia (less than 70,000/mm3) (n = 23), precipitous (30% to 50%) fall in platelet count (n = 5), or thromboses (n = 6) developed while they were receiving heparin were studied. Heparin-associated antiplatelet antibodies were demonstrated in 14 infants by platelet aggregation testing. The average gestational age (29 +/- 6 weeks); birth weight (1300 +/- 945 gm); and platelet count at birth (234,000/mm3 +/- 111,000/mm3) of these 14 infants did not differ statistically from the 20 infants without heparin-associated antiplatelet antibodies. An umbilical artery catheter was inserted in all infants except a single patient from each group. Aortic thrombosis was documented by abdominal ultrasonography in 11 of 13 (85%) infants with heparin-associated antiplatelet antibodies. One patient died with a midgut volvulus before the aorta could be examined. Five aortic thromboses were detected in the 20 infants without heparin-associated antiplatelet antibodies. Bleeding was not associated with the heparin-induced thrombocytopenia. One patient with previously demonstrated thrombocytopenia and heparin-associated antiplatelet antibodies had recurrent thrombocytopenia when reexposed to heparin; her platelet count recovered after heparin withdrawal. Thus heparin-induced thrombocytopenia does occur in preterm and term infants receiving heparin and is associated with arterial thromboses. Therefore infants receiving any form or amount of heparin must be carefully monitored for heparin-induced thrombocytopenia.1+

Renal Failure in the Newborn

From the Departments of Child Health and Pathology, University of Missouri-Columbia School of Medicine, Columbia, Missouri 65212. Post-dactoral Neonatal Fellow, Department of Child Health. t Director of Perinatal Medicine, and Associate Professor, Departments of Child Health and Obstetrics/ Gynecology. ‡ Assistant Professor, Department of Child Health. § Assistant Professor, Departments of Child Health and Pathology, and Associate Director, Clinical Research Center (correspondence). Received for publication August, 1978; revised January, 1979 and accepted February 9, 1979. RENAL FAILURE is a serious, potentially ~~~~ serious, fatal illness in newborn infants. The diagnosis is frequently difficult, as diagnostic maneuvers appropriate to older children and adults are technically difficult, and adult values of renal function may not apply to the infant who has immature kidneys. 1-4 Treatment, including dialysis, is frequently uneffectual.5,6 To help determine the most common clinical presentation of newborn infants with renal failure,

Ceruloplasmin and alkaline phosphatase levels in cord serum of term, preterm, and physiologically jaundiced neonates

Ceruloplasmin levels were found to be significantly lower (35 per cent, p < 0.001) in cord serum from neonates who developed clinical physiological jaundice than in cord serum from normal newborns. Levels were also lower (35 per cent, p < 0.001) in preterm than in term infants. However, ceruloplasmin levels in cord serum were 25 to 30 per cent lower in neonates who developed clinical physiological jaundice than in normal infants of similar gestational age. No difference in alkaline phosphatase levels was observed between the term and preterm cord serum.

Twenty-seven years of experience with oral vitamin K1 therapy in neonates

Healthy term infants born at the University of Missouri have received vitamin K prophylaxis as a single oral dose since 1967. A retrospective study was undertaken to determine whether either hemorrhagic disease of the newborn or any unexplained intracranial hemorrhage occurred in an infant who received orally administered vitamin K, but none could be found in three separate databases. We conclude that we have met our duty of providing appropriate care.

DIAGNOSIS OF RENAL FAILURE IN THE NEWBORN

Diagnosis of renal failure in newborn infants is difficult due to immaturity of the kidney and technical factors. Utilization of urine to plasma ratios of urea (U/P U), creatinine (U/P Cr), sodium (U/P Na), and fractional sodium excretion (FE/Na) obviate the use of timed urine collections. FE/Na is calculated as:Measurement of U/P Na, U/P Cr or U/P U and FE/Na were performed in 11 premature and full term infants with demonstratable renal failure, and in 9 infants of various gestational ages with pre-renal oliguria.One patient with renal failure had FE/Na values below 3-5. and no infant with pre-renal oliguria had values above 3-5- However, 2 infants with renal failure had U/P U values above 11 and 4 infants with ollguria had values less than 11. FE/Na appears to be a useful adjunct to diagnosis of renal failure in the newborn and appears to be better than U/P U alone.