Neonatal hyperbilirubinemia associated with glucose-6-phosphate dehydrogenase deficiency in Sephardic-Jewish neonates: incidence, severity, and the effect of phototherapy.

Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency is frequently associated with neonatal hyperbilirubinemia, and sometimes kernicterus, often in the absence of any identifiable trigger or hematological evidence of hemolysis. The aim of this study was to compare the incidence and severity of, and the effect of phototherapy on, jaundice in G 6-PD-deficient vs G-6-PD-normal neonates in the Sephardic-Jewish community. Healthy term newborns, born to mothers of families stemming from geographic areas known to be "at risk" for G-6-PD deficiency, were screened for the condition and surveyed for hyperbilirubinemia. Seventy-five G-6-PD-deficient neonates formed the study group, while 266 neonates with normal levels of the enzyme formed the control group. Neonates with any other identifiable cause for jaundice were excluded. Phototherapy was commenced when the serum bilirubin levels reached 16 mg/dL (274 mumol/L) or more, and it was discontinued at 12 mg/dL (205 mumol/L) or less. Hyperbilirubinemia developed in 27 (36%) of the deficient neonates (serum total bilirubin greater than 13.9 mg/dL [238 mumol/L]), compared with 50 (18.8%) of control neonates (P = .002), while 20 (26.7%) of the study group required phototherapy, compared with 31 (11.7%) of control neonates (P = .002). Two neonates in the study group required exchange transfusion (serum bilirubin greater than 20 mg/dL [342 mumol/L]), vs 0 in the control group (not significant).(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of feeding type on the efficacy of phototherapy

OBJECTIVE: The objective of this study was to assess the efficacy of phototherapy for nonhemolytic hyperbilirubinemia and rebound bilirubin levels in breast-fed newborns as compared with mixed-fed (breast milk and formula) newborns. STUDY DESIGN/SETTING: Prospective study of effects of feeding type on response to phototherapy in newborns. METHODS: The subjects were 53 full-term healthy newborns with nonhemolytic hyperbilirubinemia [defined as total serum bilirubin 12 mg/dL (205.2 micromol/L) in the first 48 hours of life or 15 mg/dl (256.5 micromol/L), on subsequent days]. Groups were formed according to type of feeding. Group 1 consisted of 28 breast-fed newborns and group 2 consisted of 25 mixed-fed newborns. Phototherapy was terminated when total serum bilirubin concentration fell to 14 mg/dL (< 239.4 micromol/L). Rebound bilirubin measurements were obtained 24 hours after phototherapy ended. RESULTS: The groups were comparable with respect to age at the start of phototherapy. The amount of weight loss (relative to birth weight) recorded at the start of phototherapy was significantly greater in group 1 than in group 2 (8.1+/- 3.9% vs. 5.4+/- 2.6% p = 0.004). The duration of phototherapy was significantly longer in group 1 than in group 2 (38.6+/- 12.6 h vs. 26.8+/- 9.4 h; P < 0.001). The 24-hour rate of decrease in bilirubin concentration in group 2 was significantly higher than that in group 1 [5.4+/- 2.2 mg/dL/d (92.3+/-37.6 micromol/L/d) vs. 4+/- 1.3 mg/dL/d (68.4+/- 22.2 micromol/L/d); p = 0.01]. The overall rate of decrease in bilirubin concentration in group 1 was significantly lower than that in group 2 [0.16+/- 0.05 mg/dL/h (2.73+/- 0.85 micromol/L/h) vs. 0.22+/- 0.09 mg/dL/h (3.76+/- 1.53 micromol/L/h); p = 0.01]. There was no significant difference between the two groups with respect to rebound bilirubin concentration (P = 0.184). Conclusion: Phototherapy effectively reduced bilirubin levels in breastfed newborns with hyperbilirubinemia, but these patients show significantly slower response to this treatment than mixed-fed newborns.     

Comparison of the effectiveness of phototherapy and exchange transfusion in the management of nonhemolytic neonatal hyperbilirubinemia.

The relative effectiveness of phototherapy and exchange transfusion for nonhemolytic neonatal hyperbilirubinemia was compared in two closely matched groups of infants. Although the exchange transfusion achieved an immediate reduction of bilirubin level, the "rebound" was rapid and tended to offset this reduction. The more gradual and steady effect of phototherapy resulted in a significantly lower serum bilirubin level at 1, 2, and 3 days after commencement of therapy; the rebound after phototherapy was small. Phototherapy was demonstrated to be more effective than exchange transfusion in achieving prolonged reduction of bilirubin levels for nonhemolytic hyperbilirubinemia. With more efficient lamps delivering more energy in the desired spectrum, it would seem feasible to treat hyperbilirubinemia of whatever etiology with this safer and more convenient form of therapy, though sometimes only as in adjunct therapy.     

Neonatal hyperbilirubinemia and physical and cognitive performance at 17 years of age

To estimate the effect of neonatal hyperbilirubinemia on long-term cognitive ability in full-term newborns with a negative Coombs test, we performed a 17-year historical prospective study of 1948 subjects. Intelligence tests and medical examinations performed at the military draft board were stratified according to serum bilirubin concentration. A logistic regression analysis was used to adjust for the confounding effects of gestational age, birth weight, Apgar score, ethnic origin, socioeconomic class, paternal education, birth order, and the administration of phototherapy and exchange transfusion. No direct linear association was shown between neonatal bilirubin levels and intelligence test scores or school achievement at 17 years of age. However, the risk for low intelligence test scores (IQ score less than 85) was found to be significantly higher (P = .014) among full-term male subjects with serum bilirubin levels above 342 mumol/L (20 mg/dL) (odds ratio, 2.96; 95% confidence interval, 1.29-6.79). This association was not observed among female subjects. We conclude that severe neonatal hyperbilirubinemia, among full-term male newborns with a negative Coombs test, could be associated with lower IQ scores at 17 years of age.     

Double versus single phototherapy in term newborns with significant hyperbilirubinemia

The efficacy of double phototherapy, in the form of conventional phototherapy with special blue light plus fiberoptic phototherapy, was compared with conventional phototherapy consisting of special blue lamps alone in a relatively larger series of term newborns with significant hyperbilirubinemia. During the study period the sum of the average spectral irradiances in the double phototherapy group was significantly higher than that of the single phototherapy group (p < 0.05). Phototherapy was effective in decreasing bilirubin levels in both groups, but the response was greater in the double phototherapy group; the duration of exposure to phototherapy was significantly shorter (31.2 +/- 8.5 vs. 38.98 +/- 14.7 h, p < 0.05), and the overall bilirubin decline rate as mumol/l/h and per cent/h was significantly greater in the double phototherapy group (4.1 +/- 1.37 vs. 3.3 +/- 0.86 mumol/l/h, and 1.29 +/- 0.38 vs. 1.02 +/- 0.44 per cent/h, p < 0.05). In phototherapy treatment of term newborns with significant hyperbilirubinemia, double phototherapy provided more rapid and effective bilirubin reduction than conventional phototherapy alone due to higher spectral irradiance and larger body surface area exposed to phototherapy. The value of double phototherapy in the treatment of newborns with hemolytic hyperbilirubinemia remains to be determined.     

A clinical trial of fiberoptic phototherapy vs conventional phototherapy.

We conducted a randomized, controlled trial to compare fiberoptic phototherapy with conventional phototherapy in healthy jaundiced newborns with birth weights greater than 2500 g. Twelve patients received fiberoptic phototherapy and 14 patients received conventional phototherapy. There were no significant differences between the groups with respect to birth weight, gestational age, feeding method, presence of hemolytic disease, hematocrit, reticulocyte count, or initial serum bilirubin level. Measured irradiance at 425 to 475 nm for conventional phototherapy was greater than that of fiberoptic phototherapy (9.2 +/- 0.9 microW/cm2 per nanometer vs 8.2 +/- 1.2 microW/cm2 per nanometer). Both types of phototherapy lowered the level of serum bilirubin after 18 hours of therapy (fiberoptic group, from 231 +/- 29 to 210 +/- 24 mumol/L; conventional group, from 231 +/- 21 to 188 +/- 26 mumol/L), but the mean serum bilirubin level was lower after 18 hours of therapy in the conventional phototherapy group (188 +/- 26 vs 210 +/- 24 mumol/L). There were no side effects in either group of newborns. Both methods of phototherapy decreased the serum bilirubin level, but conventional phototherapy did so more effectively, probably because of its greater irradiance.     

Beneficial effects of early hypocaloric enteral feeding on neonatal gastrointestinal function: preliminary report of a randomized trial

In a prospective randomized trial, we studied the effects of early hypocaloric enteral feedings (PO) begun at 48 hours of age in 19 infants compared with 20 infants who received no enteral feedings (NPO) for at least the first 9 days of life. Both groups initially received the majority of their calories by parenteral alimentation. The groups were similar with respect to birth weight, gestational age, sex, Apgar score, and major neonatal diagnoses. The early enteral feeds proved to be significantly beneficial without an increased incidence of complications. The PO group reached full enteral feedings faster than the NPO group (31.2 vs 47.3 days). The PO group had a greater decline in serum bilirubin concentration over the first 2 weeks of life and spent less time under phototherapy (6.8 vs 9.5 days). Less cholestasis was observed among the PO infants (6.7% vs 33%), and peak direct bilirubin levels were also lower (0.7 vs 2.5 mg/dL). Osteopenia of prematurity, manifested by significantly lower alkaline phosphatase activity, was also decreased in the PO group, perhaps because of greater calcium intake during the first month among PO infants (1.3 vs 0.8 g). Compared with complete bowel rest, early onset of hypocaloric enteral feedings has beneficial effects on indirect hyperbilirubinemia, cholestatic jaundice, and metabolic bone disease of very low birth weight infants.     

A randomized controlled trial of fluid supplementation in term neonates with severe hyperbilirubinemia

OBJECTIVE: To evaluate the effectiveness of fluid supplementation in decreasing the rate of exchange transfusion and the duration of phototherapy in term neonates with severe nonhemolytic hyperbilirubinemia. STUDY DESIGN: This was a randomized controlled trial conducted in a tertiary care referral unit in northern India. Seventy-four term neonates with severe nonhemolytic hyperbilirubinemia (total serum bilirubin > 18 mg/dL [308 micromol/L] to < 25 mg/dL [427 micromol/L]). The subjects were randomized to an "extra fluids" group (intravenous fluid supplementation for 8 hours and oral supplementation for the duration of phototherapy; n = 37) or a control group (n = 37). RESULTS: At inclusion, 54 infants (73%) had high serum osmolality, including 28 (75%) in the extra fluids group and 26 (70%) in the control group. The proportion of infants who underwent exchange transfusion was lower in the extra fluids group than in the control group: 6 (16%) versus 20 (54%)(P = .001; relative risk = 0.30; 95% confidence interval = 0.14 to 0.66). The duration of phototherapy was also shorter in the extra fluids group: 52 +/- 18 hours versus 73 +/- 31 hours (P = .004). CONCLUSION: Fluid supplementation in term neonates presenting with severe hyperbilirubinemia decreased the rate of exchange transfusion and duration of phototherapy.     

A new device for phototherapy of neonatal jaundice]

The effectiveness of a new device for phototherapy in the treatment of nonhemolytic hyperbilirubinemia (Wallaby Phototherapy System) was evaluated. 46 healthy term infants, appropriate for gestational age and with serum bilirubin > 12 mg/dl in the first 3 days of life or > 15 mg/dl after 3rd day were randomly assigned to a treatment group (24 hours of light exposure with Wallaby Phototherapy System) and to a control group (any treatment for hyperbilirubinemia). Body temperature, weight, feeding and hydration were recorded during the study period. Serum bilirubin and haematocrit were done every 12 hours in all babies. In the treated group we found a decrease of 5.1% and of 7.8% at 12 and 24 hours, while an increase of 3.37% and of 2.9% at 12 and 24 hours was found in the control group. After 24 hours the serum bilirubin level was significantly lower in the treated group than in the control group (p < 0.05). No newborn of the treated group needed conventional phototherapy versus 4 control infants (17.4%). The conclusion of our study is that the Wallaby System is useful in the treatment of neonatal nonhemolytic hyperbilirubinemia even if its effectiveness for higher bilirubin levels has still to be tested.     

Relationship of serum bilirubin levels to ototoxicity and deafness in high-risk low-birth-weight infants

During a 4-year period, 12 premature infants, all less than 34 weeks of gestation and all with a bilirubin level above 240 mumol/L (14 mg/dL) were determined to have bilateral sensorineural deafness. In order to to investigate how far the hyperbilirubinemia or any a associated factor might have been a causative factor, all infants of 34 weeks of gestation or less who had a serum bilirubin level above 240 mumol/L were investigated. For a period of 4 years, 99 infants meeting these criteria were classified as high risk or low risk on the basis of perinatal risk factors. Eight of the 22 high-risk infants with birth weight less than 1,500 g, but only two of 43 high-risk infants with birth weight greater than 1,500 g were deaf (P less than .05). The deaf infants were also matched with infants of normal hearing who had similar bilirubin levels and the same number of adverse perinatal factors. The mean duration of hyperbilirubinemia was significantly longer in the deaf infants (P less than .02), and they appeared to have a greater number of acidotic episodes while they were hyperbilirubinemic. These findings suggest that in healthy preterm infants with birth weight greater than 1,500 g, high bilirubin levels carry little risk, whereas a serum bilirubin level greater than 240 mumol/L in high-risk preterm infants with birth weight of 1,500 g or less is associated with a high risk of deafness.     

Double versus single phototherapy in low birth weight newborns.

Conventional phototherapy systems that simultaneously irradiate the front and the back of the baby lower the serum bilirubin level more rapidly than one-sided systems, but they are impractical. Fiberoptic phototherapy makes it easy to administer conventional phototherapy from above while the infant lies on a fiberoptic phototherapy blanket. Newborns with birth weights less than 2500 g were randomly assigned to receive either single (n = 37) or double (n = 33) phototherapy. The groups were similar in clinical and laboratory characteristics. After 18 hours of therapy the serum bilirubin concentration declined by 31 +/- 11% in the double and 16 +/- 15% in the single phototherapy group (2.9 +/- 1.1 vs 1.6 +/- 1.4 mg/dL), and the difference in the total serum bilirubin levels after 18 hours of therapy was significant (double phototherapy group 7.1 +/- 2.7 mg/dL vs single phototherapy group 8.2 +/- 2.6 mg/dL). After 18 hours of treatment the serum bilirubin level was less than the phototherapy threshold level in 26 of 37 single phototherapy patients vs 32 of 33 double phototherapy patients. Double phototherapy was well tolerated. It is concluded that this type of double phototherapy is more effective than single phototherapy in low birth weight newborns. Double phototherapy may be useful when it is necessary to reduce an elevated serum bilirubin level as rapidly as possible or when the bilirubin level is rising with single phototherapy.     

Efficacy of oral phenobarbitone in term "at risk" neonates in decreasing neonatal hyperbilirubinemia: a randomized double-blinded, placebo controlled trial

OBJECTIVE: To evaluate the efficacy of oral phenobarbitone in "at risk " term neonates (with high cord bilirubin) in decreasing hyperbilirubinemia. DESIGN: Double blind, placebo-control, randomized trial. SETTING: Tertiary level neonatal unit. OUTCOME: Primary-hyperbilirubinemia defined as total serum bilirubin (TSB) greater than 13 mg/dL. Secondary-TSB at 72 +/- 12 hr, need for phototherapy or exchange transfusion and side effects of phenobarbitone therapy. METHODS: All consecutively born term healthy neonates with cord bilirubin > or = 2.5 mg/dL were randomly assigned to receive either phenobarbitone (n = 37) or placebo (n = 38) after obtaining informed consent. Phenobarbitone was administered orally (5 mg/kg/day) for 3 days starting within 12 hours of birth. The neonates were followed up till seven days of life. TSB was estimated in neonates who developed jaundice with clinically assessed level of 8-10 mg/dL and at 72 +/-12 hours of age in 55 neonates. RESULTS: The baseline characteristics were similar in two groups. There was no significant reduction in incidence of hyperbilirubinemia in phenobarbitone group compared to in placebo group (6/37 (16.2%) versus 13/38 (34.3%); RR 0.47, 95% confidence interval: 0.20-1.11; risk difference: -18.1%, 95% confidence interval: -39.5 to 3.3%). However TSB at 72 +/-12 hours in phenobarbitone group (mean +/- S.D: 10.0 +/- 3.7 mg/dL) was significantly lesser than in placebo group (mean +/- S.D: 12.3 +/- 3.3 mg/dL) (difference of means: -2.3 mg/dL, 95% confidence interval: -3.9 to -0.7 mg/dl, P = 0.018). No significant difference with respect to need for treatment was observed in two groups. No significant adverse effects of phenobarbitone were noted. CONCLUSIONS: Prophylactic phenobarbitone is not helpful in reducing the incidence of hyper-bilirubinemia in "at risk" term neonates.     

Alkaline phosphatase as an early marker of hemolysis in newborns

Background: Early diagnosis and appropriate management of neonatal hyperbilirubinemia are very important in order to prevent bilirubin encephalopathy and kernicterus. Several diagnostic tests may be used for this purpose, including bilirubin level itself. The aim of the present study was to investigate whether serum alkaline phosphatase (ALP), which is an intracellular enzyme found abundantly in red blood cells, could be used for the early diagnosis and prediction of hyperbilirubinemia in newborns. Methods: A total of 100 babies were evaluated, starting from the sixth hour after birth, and serum ALP and bilirubin levels were analyzed. Results: ALP levels were significantly higher in babies requiring therapy such as phototherapy or exchange transfusion (247.01 ± 67.44 IU/L vs 154.25 ± 56.07 IU/L). ALP levels rose significantly with rising total bilirubin level. Conclusion: ALP levels at the sixth hour of life may be a significant predictor of developing hemolysis and hyperbilirubinemia requiring treatment.     

Carboxyhemoglobin Measurements in the Diagnosis of ABO Hemolytic Disease

To assess hemolysis in hyperbilirubinemic infants with ABO isoimmunization, we measured the carboxyhemoglobin (HbCO) concentrations in full-term infants with ABO isoimmunization during the first week of life. Two groups of infants, ABO compatible (n=34) and ABO incompatible (n=30), were further divided into two groups with and without hyperbilirubi-nemia. All the infants from ABO incompatible pregnancies showed a positive indirect Coombs' test. The groups with hyperbilirubinemia included infants with maximum serum total bilirubin levels about 15 mg/dL and infants treated by phototherapy or exchange transfusion. In the ABO incompatible infants, the HbCO levels in those with hyperbilirubinemia were significantly higher than in infants without hyperbilirubinemia during the first week after birth (p < 0.01 at 24, 72, 120 hours after birth, respectively). The levels of HbCO in the ABO incompatible infants with hyperbilirubinemia were significantly higher compared with the levels in the ABO compatible infants with hyperbilirubinemia (p < 0.05 at 24 hours, p < 0.01 at 72 and 120 hours after birth, respectively). HbCO measurement may facilitate the early diagnosis of hemolytic disease and the prediction of jaundice caused by ABO isoimmunization.     

不同方法对重症新生儿高胆红素血症的疗效观察

探讨不同治疗方法对重症新生儿高胆红素血症的治疗效果 ,将 43例重症新生儿高胆红素血症患儿 (达换血标准 )按治疗方法分为 3组。光疗组 1 5例 ,予以药物治疗及光疗直至退黄 ;丙球组 1 6例 ,药物及光疗同前组 ,另加静脉输注丙种球蛋白(简称丙球 )× 3d ;换血组 1 2例 ,予以换血 ,换血前后药物治疗及光疗同前二组。所有三组患儿分别于治疗前 ,治疗后第 1d、4d、7d测血胆红素。结果 :( 1 )血清胆红素值 :治疗第 1d换血组明显低于丙球组及光疗组 (P均 <0 0 1 ) ,但光疗组与丙球组之间无统计学意义 (P >0 0 5) ;治疗第 4d、7d三组间比较均有显著性差异 (P均 <0 0 1 ) ;( 2 )所需光疗时间及黄疸消退时间 :换血组明显低于丙球组及光疗组 (P均 <0 0 1 ) ,但光疗组与丙球组之间无统计学意义 (P >0 0 5) ;( 3)临床情况 :43例患儿黄疸均消退 ,换血组 1 2例无胆红素脑病、贫血发生 ;丙球组胆红素脑病 2例 ,明显贫血 5例 ;光疗组胆红素脑病 3例 ,明显贫血 5例 ,亦因拒绝输血而未予纠正。结论 :换血疗法仍然是治疗重症新生儿黄疸的最佳选择     

An evidence-based review of important issues concerning neonatal hyperbilirubinemia

This article is adapted from a published evidence report concerning neonatal hyperbilirubinemia with an added section on the risk of blood exchange transfusion (BET). Based on a summary of multiple case reports that spanned more than 30 years, we conclude that kernicterus, although infrequent, has at least 10% mortality and at least 70% long-term morbidity. It is evident that the preponderance of kernicterus cases occurred in infants with a bilirubin level higher than 20 mg/dL. Given the diversity of conclusions on the relationship between peak bilirubin levels and behavioral and neurodevelopmental outcomes, it is apparent that the use of a single total serum bilirubin level to predict long-term outcomes is inadequate and will lead to conflicting results. Evidence for efficacy of treatments for neonatal hyperbilirubinemia was limited. Overall, the 4 qualifying studies showed that phototherapy had an absolute risk-reduction rate of 10% to 17% for prevention of serum bilirubin levels higher than 20 mg/dL in healthy infants with jaundice. There is no evidence to suggest that phototherapy for neonatal hyperbilirubinemia has any long-term adverse neurodevelopmental effects. Transcutaneous measurements of bilirubin have a linear correlation to total serum bilirubin and may be useful as screening devices to detect clinically significant jaundice and decrease the need for serum bilirubin determinations. Based on our review of the risks associated with BETs from 15 studies consisting mainly of infants born before 1970, we conclude that the mortality within 6 hours of BET ranged from 3 per 1000 to 4 per 1000 exchanged infants who were term and without serious hemolytic diseases. Regardless of the definitions and rates of BET-associated morbidity and the various pre-exchange clinical states of the exchanged infants, in many cases the morbidity was minor (eg, postexchange anemia). Based on the results from the most recent study to report BET morbidity, the overall risk of permanent sequelae in 25 sick infants who survived BET was from 5% to 10%.     

Comparison of Two Phototherapy Methods (Prophylactic vs Therapeutic) for Management of Hyperbilirubinemia in Very Low Birth Weight Newborns

Objective

Preterm and low birth weight (LBW) infants are at greater risk of developing bilirubin-associated brain damage compared with term infants. Certainly, phototherapy, if used appropriately, is capable of controlling the bilirubin levels in LBW infants; but there is not a unique phototherapy treatment strategy in LBW infants. This study was designed to compare the prophylactic phototherapy and late treatment of jaundiced newborns weighing 1000-1500 grams.

Methods

Sixty newborns with birth weight 1000–1500 g were studied. They were divided into two groups: the “Prophylactic” group, in which phototherapy started within six hours after birth and continued for at least 96 hours, and the "Treatment" group, which received phototherapy when indicated according to birth weight and suspended when bilirubin level fell below 50% of bilirubin level for blood exchange. Mean value of daily transcutaneous bilirubin (TCB), duration of phototherapy, the need for blood exchange, and the highest TCB value in both groups were analyzed.

Findings

In the prophylactic group, the highest daily mean rate of TCB was 7.71±1.84 mg/dl, which happened on the third day. In the treatment group, it was 8.74±1.72 mg/dl on the fourth day after birth. The TCB values in prophylactic group were significantly less than those of the treatment group only on the fourth and fifth days after birth (P<0.001). Although the median duration of phototherapy in the treatment group was shorter than that of the prophylactic group (137.60±57.39 vs 168.71±88.01 hours, respectively), this difference was not statistically significant. Only one neonate needed blood exchange in the treatment group.

Conclusion

The prophylactic phototherapy treatment for babies weighing 1000–1500 g significantly decreases bilirubin levels on the fourth and fifth days after birth but the clinical course of hyperbilirubinemia does not alter in LBW infant, as indicated by the non-significant change in the duration of phototherapy.     

Developmental changes in serum half-life of (EZ)-cyclobilirubin

BACKGROUND: Phototherapy has been a standard treatment for neonatal hyperbilirubinemia for more than 40 years, but it has remained sub-optimal. AIMS: To clarify the developmental changes in parameters of (4E, 15Z)-cyclobilirubin ((EZ)-C) elimination in order to obtain basic data for establishing optimal phototherapy. STUDY DESIGN: Blood samples were taken at regular intervals after stopping phototherapy, and bilirubin fractions were analyzed by high-performance liquid chromatography. SUBJECTS AND METHODS: The subjects were 46 infants with hyperbilirubinemia who underwent phototherapy. The gestational age and birth weight of the subjects ranged from 25.0 to 41.0 weeks and from 656 to 3810 g, respectively, and the age at cessation of phototherapy was a median of 5 days. A kinetic model of (EZ)-C elimination was established, and the serum half-life of (EZ)-C was calculated on the basis of the determined model. Relationships of the half-life of (EZ)-C with birth weight and gestational age were investigated. RESULTS: Serum (EZ)-C elimination followed a first-order kinetic model in 43 infants and a zero-order kinetic model in three extremely low birth weight infants. The half-life of (EZ)-C calculated on the basis of a first-order elimination model in serum ranged from 68 to 274 min and showed weak negative correlations with birth weight and gestational age. CONCLUSIONS: Serum (EZ)-C excretion followed a first-order kinetic model in most of the neonates. The half-life of (EZ)-C becomes more prolonged in the very low birth weight infant and early gestational age.     

Glucose-6-phosphate dehydrogenase deficiency in neonatal indirect hyperbilirubinemia

The aim of this article is to investigate the prevalence of Glucose-6-phosphate dehydrogenase (G6PD) deficiency in neonatal hyperbilirubinemia and to compare the clinical presentation and course of G6PD-deficient and normal patients. This study included a total of 624 term neonates with indirect hyperbilirubinemia from March 2001 to September 2004. Birth weight, sex, weight at admission, serum bilirubin at admission, maximum bilirubin, phototherapy duration, duration of hospitalization and the need for exchange transfusion were recorded. Laboratory evaluations included blood group typing of mother and newborn, complete blood count, peripheral blood smear, serum total and direct bilirubin, direct coombs test, reticulocyte count, serum-free T4 and TSH, urine analysis, urinary reducing substance and erythrocyte G6PD level. The analysis of the results indicated that 24 neonates with indirect hyperbilirubinemia were G6PD-deficient. No statistically significant difference was detected between G6PD-deficient and normal groups in relation to the time of onset of jaundice, reticulocyte count, hematocrit level, phototherapy duration and duration of hospitalization. Serum bilirubin at admission, maximum serum bilirubin level and the need for exchange transfusion were higher in G6PD-deficient group. From this study our conclusion is that the G6PD deficiency is a common enzyme defect causing severe indirect hyperbilirubinemia which may result in kernicterus. Early neonatal screening programmes should be instituted in countries where the deficiency is prevalent.     

Bilirubin rebound after intensive phototherapy for neonatal jaundice

This study was conducted to determine the incidence and magnitude of postphototherapy bilirubin rebound in neonates. Subjects included inborn neonates needing phototherapy for hyperbilirubinemia. Standard guidelines were used to start and stop phototherapy. Rebound bilirubin was measured 24±6 h after stopping phototherapy. Significant bilirubin rebound (SBR) was defined as postphototherapy bilirubin level needing reinstitution of phototherapy. Among 245 neonates with hyperbilirubinemia, post-phototherapy bilirubin estimation was done in 232 neonates. A total of 17 (7.3%) neonates developed SBR. In neonates with SBR, bilirubin increased by 2.3 mg/dL (95% CI 1.6–3.0) after stopping phototherapy. Risk factors for SBR included birth at <35 weeks of gestation (RR 4.3, 95% CI 1.5–12.0), birthweight <2000 g (RR 3.2, 95% CI 1.0–10.3) and onset of jaundice at <60 h of age (RR 3.3, 95% CI 1.2–9.0). Post-phototherapy discharge and follow-up planning should take into account these risk factors.