Urinary potassium loss in children with acute liver failure and acute viral hepatitis.

OBJECTIVES: The aim of the present study was to determine urinary potassium (K⁺) loss (as measured by fractional excretion of K⁺ [FEK] and transtubular K⁺ gradient [TTKG]) in children with acute liver failure (ALF) and acute viral hepatitis (AVH) at the time of presentation to the hospital and day 45 of follow-up. METHODS: Twenty-five patients with ALF and 84 patients with AVH were worked up for clinical features, liver function tests, and hepatitis viral infections and monitored for outcome. All of the patients with ALF were hospitalized. FEK and TTKG were estimated on the day patients were first seen in the hospital or hospitalized and later on day 45 of follow-up. RESULTS: Sixty percent (15/25) of patients with ALF were hypokalemic (serum K⁺ <3.5 mEq/L) as compared with only 12% (10/84) in the AVH group (P = 0.000) at the time of presentation in the hospital. Inappropriate kaliuresis was present in 80% to 100% of hypokalemic children compared with 0% to 30% of normokalemic individuals at the time of first contact in either the ALF or AVH group. Inappropriate urinary K⁺ loss and serum K⁺ levels in the hypokalemic individuals improved as the hepatic functions recovered by day 45 of follow-up (P = 0.014-0.000). No significant change in kaliuresis was observed among normokalemic subjects between first contact and later on day 45 of follow-up (P = 0.991-0.228). Despite different physiologic mechanisms, appropriateness of kaliuresis measured by FEK and TTKG showed results in the same direction. CONCLUSIONS: Hypokalemia and inappropriate kaliuresis observed during the acute phase of ALF and AVH reversed with clinical and biochemical recovery. In the absence of major gastrointestinal losses and renal abnormalities, there is need to investigate the contributory role of factors like hyperaldosteronism and food intake, which may have therapeutic implications.

Intraventricular hemorrhage and neurodevelopmental outcomes in extreme preterm infants.

OBJECTIVE: Not many large studies have reported the true impact of lower-grade intraventricular hemorrhages in preterm infants. We studied the neurodevelopmental outcomes of extremely preterm infants in relation to the severity of intraventricular hemorrhage. METHODS: A regional cohort study of infants born at 23 to 28 weeks' gestation and admitted to a NICU between 1998 and 2004. Primary outcome measure was moderate to severe neurosensory impairment at 2 to 3 years' corrected age defined as developmental delay (developmental quotient >2 SD below the mean), cerebral palsy, bilateral deafness, or bilateral blindness. RESULTS: Of the 1472 survivors assessed, infants with grade III-IV intraventricular hemorrhage (IVH; n = 93) had higher rates of developmental delay (17.5%), cerebral palsy (30%), deafness (8.6%), and blindness (2.2%). Grade I-II IVH infants (n = 336) also had increased rates of neurosensory impairment (22% vs 12.1%), developmental delay (7.8% vs 3.4%), cerebral palsy (10.4% vs 6.5%), and deafness (6.0% vs 2.3%) compared with the no IVH group (n = 1043). After exclusion of 40 infants with late ultrasound findings (periventricular leukomalacia, porencephaly, ventricular enlargement), isolated grade I-II IVH (n = 296) had increased rates of moderate-severe neurosensory impairment (18.6% vs 12.1%). Isolated grade I-II IVH was also independently associated with a higher risk of neurosensory impairment (adjusted odds ratio 1.73, 95% confidence interval 1.22-2.46). CONCLUSIONS: Grade I-II IVH, even with no documented white matter injury or other late ultrasound abnormalities, is associated with adverse neurodevelopmental outcomes in extremely preterm infants.

Early diffusion-weighted magnetic resonance imaging findings in neonatal herpes encephalitis.

Neonatal herpes encephalitis is usually caused by herpes simplex virus type 2 and results in significant morbidity and mortality. Imaging diagnosis with ultrasound, computed tomography scan and conventional magnetic resonance imaging may be normal in the early course of the disease. In this case diffusion-weighted magnetic resonance imaging detected the disease process earlier and better than the conventional T2-weighted or fluid-attenuated inversion recovery imaging sequences. The use of diffusion-weighted magnetic resonance imaging in neonatal herpes encephalitis proved to be a useful tool in the early stage of the disease.