Effect of lactate, pyruvate, acetone, acetoacetate, and beta-hydroxybutyrate on albumin binding of bilirubin

Lactate, pyruvate, acetone, acetoacetate, and beta-hydroxybutyrate were tested for their bilirubin-displacing effect on human serum albumin. Only lactate had a significant effect at levels found in asphyxiated infants (up to 20 mM). The reserve albumin equivalent for binding bilirubin was determined, using the deputy ligand monoacetyldiaminodiphenyl sulfone (MADDS), in adult human serum albumin solution, neonatal serum, and neonatal albumin solution. Twenty mM lactate caused a 23% decrease of reserve albumin when adult albumin was used, but did not cause any change of binding when neonatal serum or neonatal albumin solution was used. It is unlikely that endogenous substances, acting as competitive ligands, cause the low binding affinity of albumin for bilirubin in sick, premature infants.     

ALBUMIN ADMINISTRATION COMBINED WITH PHOTOTHERAPY IN TREATMENT OF HYPERBILIRUBINAEMIA IN LOW-BIRTH-WEIGHT INFANTS

ABSTRACT. Ebbesen, F., and Brodersen, R. (Department of Neonatology, Rigshospitalet, Copenhagen and Institute of Medical Biochemistry, Aarhus, Denmark). Albumin administration combined with phototherapy in treatment of hyperbilirubinaemia in low-birth-weight infants. Acta Paediatr Scand, 70:649,.–Fifty-nine jaundiced light treated newborn infants with low birth weight were studied. At onset of phototherapy 30 infants received 1 g human serum albumin per kg body weight as a 9 % solution containing sodium caprylate and N-acetyltryptophan as stabilizers. 29 infants did not receive human serum albumin and served as controls. Blood samples were taken before initiation of the therapy and again 24 and 48 h thereafter, and the following determinations were made: Serum concentrations of unconjugated bilirubin, albumin, reserve albumin for binding of bilirubin by the [^l4C]-MADDS method, packed cell volume and pH. Before infusion of albumin it was found that the binding fraction of serum albumin, i.e. the sum of the serum concentrations of bilirubin-albumin and reserve albumin, constituted about half of the total serum albumin concentration. The other half was non-binding, in agreement with previous findings in neonates. The effect of albumin therapy was mainly an unexpected increase of the non-binding fraction of serum albumin, while the increase of the serum reserve albumin concentration was small and the concentration of bilirubin-albumin was not changed.     

Hepatic enzymes,their induction and usefulness in predicting maximal serum bilirubin levels in premature newborn infants

Sixty-seven babies were utilized to (a) document the serum bilirubin lowering effect and safety of a phenobarbitone and nikethamide combination in neonatal hyperbilirubinaemia of non-hemolytic origin; (b) determine whether birthweight and/or SGOT, SGPT or SGGT activity on day one of life correlated with the maximum serum bilirubin level achieved; and (c) investigate the pattern of hepatic enzyme levels in serum under normal conditions and following drug induction. Results indicate a significantly lower serum bilirubin level in the treated group of babies. Birthweight and day one SGGT levels, and SGGT/birthweight ratio correlated well with the maximum serum bilirubin reached, the latter ratio being particularly useful in predicting the degree of hyperbilirubinaemia.     

BILIRUBIN, RESERVE ALBUMIN FOR BINDING OF BILIRUBIN AND pH IN PLASMA DURING PHOTOTHERAPY (ORDINARY AND DOUBLE LIGHT) OF TERM NEWBORN INFANTS

ABSTRACT. Ebbesen, F. (Department of Neonatology, Rigshospitalet, Copenhagen, Denmark). Bilirubin, reserve albumin for binding of bilirubin and pH in plasma during phototherapy (ordinary and double light) of term newborn infants. Acta Paediatr Scand, 70:223, 1981. –Forty-five term newborn infants with uncomplicated hyperbilirubinaemia were treated continuously with phototherapy for 24 hours. Twenty-eight infants received double light treatment and 17 infants ordinary phototherapy. During both treatments a significant decrease in the serum unconjugated bilirubin concentration, a significant increase in the serum reserve albumin concentration for binding of bilirubin determined by the [¹⁴C] MADDS method, and a significant decrease in the index of serum bilirubin toxicity occurred. The changes in these parameters were significantly greater during the double light treatment than during the ordinary phototherapy. During the treatment the fall in index was constant. No significant change in plasma pH was seen. Thus, the study gives further evidence that the risk of bilirubin encephalopathy is reduced by phototherapy and that double light treatment is in the respect superior to ordinary phototherapy. Prior to phototherapy the molar ratio in serum of unconjugated bilirubin plus reserved albumin for binding of bilirubin to albumin was only 0.60, on average, and during the treatment the increase in the serum reserve albumin concentration was less than the decrease in the serum bilirubin concentration. This can be explained either by the presence in infant serum of an unknown ligand interfering competitively or allosterically in the binding of MADDS and bilirubin to albumin, or by the existence of a foetal albumin with a lower affinity for MADDS than adult albumin.     

Salicylate saturation index in neonatal jaundice.

30 serum samples from premature and newborn infants with non-haemolytic hyperbilirubinaemia were analyzed to prove the accuracy of determination of albumin binding capacity for bilirubin. The salicylate method of Odell was used to determine the saturation index of albumin indicated by a decrease in optical density through displaced bilirubin. Bilirubin is stoichometrically displaced from albumin by the addition of salicylate. The values of the sautration index correspond to free binding sites. Analysis of our data demonstrated that there is no direct correlation between the saturation index (SI) and total serum bilirubin/albumin concentration quotient. Methodical errors, problems in statistics and other theoretical concepts are discussed. The salicylate method is not suitable for accurate determination of albumin binding capacity for bilirubin.     

The Serum Reserve Albumin Concentration for Monoacetyldiaminodiphenyl Sulphone and Auditory Evoked Responses during Neonatal Hyperbilirubinaemia

ABSTRACT. Auditory brainstem evoked responses (ABR) were recorded in 9 neonates with hyperbilirubinaemia. Pathological recordings were found in two children showing absence of waves and prolonged latencies. There was no correlation between latencies to waves and the total serum bilirubin concentration. The serum reserve albumin concentration for monoacetyldiaminodiphenyl sulphone (MADDS) was, however, inversely related to the latencies in the ABR recordings. Our findings suggest that the binding properties of serum albumin contribute to the risk of bilirubin toxicity and that, in this study, the reserve albumin concentration for MADDS seemed to be of Heater significance than the total bilirubin concentration.     

THE RELATIONSHIP BETWEEN SERUM BILIRUBIN AND RESERVE ALBUMIN FOR BINDING OF BILIRUBIN DURING PHOTOTHERAPY OF PRETERM INFANTS

ABSTRACT. Ebbesen, F. (Department of Neonatology, Rigshospitalet, Copenhagen, Denmark). The relationship between serum bilirubin and reserve albumin for binding of bilirubin during phototherapy of preterm infants. Acta Paediatr Scand, 70:405, 1981.–Thirty-four preterm newborn infants suffering from uncomplicated hyperbilirubinaemia were studied. The infants received ordinary phototherapy continuously during 48 hours. The serum unconjugated bilirubin concentration decreased significantly during the treatment, and a significant correlation between the changes in the serum bilirubin concentration and the changes in the serum reserve albumin concentration for binding of bilirubin measured by the [¹⁴C]MADDS method was found. The regression coefficients were -0.50 and -0.48 after 24 and 48 hours of treatment, respectively. Thus, it can be concluded that the risk of bilirubin encephalopathy is reduced by phototherapy in preterm infants.     

The serum reserve albumin concentration for monoacetyldiaminodiphenyl sulphone and auditory evoked responses during neonatal hyperbilirubinaemia

Auditory brainstem evoked responses (ABR) were recorded in 9 neonates with hyperbilirubinaemia. Pathological recordings were found in two children showing absence of waves and prolonged latencies. There was no correlation between latencies to waves and the total serum bilirubin concentration. The serum reserve albumin concentration for monoacetyldiaminodiphenyl sulphone (MADDS) was, however, inversely related to the latencies in the ABR recordings. Our findings suggest that the binding properties of serum albumin contribute to the risk of bilirubin toxicity and that, in this study, the reserve albumin concentration for MADDS seemed to be of greater significance than the total bilirubin concentration.     

An etiological study of neonatal hyperbilirubinaemia

Summary Etiological classification of neonatal jaundice based on an intensive investigation of 100 newborns, 50 having neonatal hyperbilirubinaemia (serum bilirubin more than 12 mg.%) and another 50 having milder jaundice, (serum bilirubin less than 12 mg.%) has been attempted. The two groups have been compared. The etiology in a large group of neonatal hyperbilirubinaemia (38%) cases could not be ascertained which were labelled as the ‘unknown group’. More intensive investigations with a particular reference to red cell enzyme studies is required for further evaluation of the etiological factors. From the departments of Pediatrics and Obstetrics and Gynaecology, King George’s Medical College, Lucknow.     

Bilirubin-albumin binding affinity and serum albumin concentration during intensive phototherapy (blue double light) in jaundiced newborn infants

Thirty newborn infants with normal birth weights and uncomplicated hyperbilirubinaemia were studied. Twenty three of these were treated continuously for 24h with intensive phototherapy (blue double light), and seven untreated infants served as controls. During the treatment the serum concentrations of total bilirubin and unbound bilirubin in diluted serum measured by the peroxidase method were markedly reduced. The binding affinity of bilirubin to its high affinity site on serum albumin was not affected. During the treatment a slight decrease of the serum albumin concentration occurred, and the possible causes of this observation are discussed.     

EFFECT OF EXCHANGE TRANSFUSION ON SERUM RESERVE ALBUMIN FOR BINDING OF BILIRUBIN AND INDEX OF SERUM BILIRUBIN TOXICITY

ABSTRACT. Ebbesen F. (Department of Neonatology, Rigshospitalet, Copenhagen, Denmark). Effect of exchange transfusion on serum reserve albumin for binding of bilirubin and index of serum bilirubin toxicity. Acta Paediatr Scand, 70:643,.–Seventeen newborn infants, who received their first exchange transfusion due to hyperbilirubinaemia and/or rhesus haemolytic disease, were studied. The exchange transfusions were performed with fresh, citrated blood. During the exchange transfusion a marked increase in the serum reserve albumin concentration for binding of bilirubin measured by the [^,4C]-MADDS method was observed, followed by a smaller decrease after the transfusion. Plasma pH increased both during and after the exchange transfusion. During the exchange transfusion a drastic fall in index of serum bilirubin toxicity was observed, followed by a smaller increase after the transfusion. Citrate was not found to interfere in the binding of bilirubin to albumin. The results are in agreement with the clinical finding that an exchange transfusion performed with fresh, citrated blood effectively reduces the risk of bilirubin encephalopathy. The ratio in serum of binding albumin, i.e. bilirubin plus reserve albumin, to total albumin failed to be increased by the exchange transfusion, and a decrease occurred after the transfusion. These findings indicate the presence in infant serum of non-binding albumin. Donor albumin with intact binding potential is partly transformed into the non-binding variety in the course of one hour after the transfusion. In the most severely rhesus sensitized infant a drastic decline of the serum albumin binding capacity was seen during the first day of life.     

Ceftriaxone effect on bilirubin-albumin binding

The effect of ceftriaxone on bilirubin-albumin binding was measured in vitro using the peroxidase method with human serum albumin and a dialysis rate method with adult and newborn serum. Ceftriaxone competes with bilirubin for binding to human serum albumin; the displacement constant is 1.5 X 10(4) L/mol. Therapeutic levels of ceftriaxone decrease the reserve albumin concentration in newborn serum by 39%. These results indicate that ceftriaxone may increase the risk of bilirubin encephalopathy in jaundiced premature infants.     

Spectrum of outcome in infants with extreme neonatal jaundice

The increasing number of case reports on neurologic sequelae related to hyperbilirubinaemia may represent a re-emergence of kernicterus in the industrialized world. However, not much has been written about infants who survived extreme levels of serum bilirubin without neurologic damage. We present three cases of extreme neonatal hyperbilirubinaemia, all with peak serum bilirubin levels > 600 µmol/L. Two of the infants developed neurologic sequelae, but the third infant did not. In contrast to the two with sequelae, the infant without sequelae was female, had a positive Coombs' test, less clinical signs compatible with bilirubin encephalopathy, and a shorter exposure to serum bilirubin values > 400 µmol/L. Conclusion: The basic mechanism of bilirubin neurotoxicity remains unknown, and it is not clear why some infants do not develop neurologic injury at serum bilirubin levels at which others do. We speculate that a comparison between patients with sequelae and those without may yield important information.     

COMPARISON BETWEEN TWO PREPARATIONS OF HUMAN SERUM ALBUMIN IN TREATMENT OF NEONATAL HYPERBILIRUBINAEMIA

ABSTRACT. Thirty-six newborn infants with normal birth weights and with uncomplicated hyperbilirubinaemia, treated with light, were studied. At onset of phototherapy the infants received intravenously 1 g human serum albumin (HSA) per kg body weight as a 9 % solution. Two different preparations of HSA were used and compared. One of these, HSA_I, contained sodium caprylate and N-acetyltryptophan, 5 mmol/1 of each, as stabilizers. HSA_II contained only caprylate, 5 mmol/1. Nineteen infants received HSA_I and seventeen infants HSA_II. The reserve albumin for binding of bilirubin, measured by the [¹⁴C] MADDS method, was low in both preparations in vitro. During the infusion, the serum concentrations of albumin and reserve albumin increased and the serum unconjugated bilirubin concentration decreased, resulting in a fall in the index of plasma bilirubin toxicity in all infants. After completion of the infusion, the serum concentrations of albumin and reserve albumin declined, and a slight rise in index occurred. The increase in the serum reserve albumin concentration was markedly higher during infusion of HSA_II than of HSA_I. It is concluded that infusion of both HSA preparations during phototherapy provides an immediate protection against bilirubin encephalopathy. HSA_I is inferior to HSA_II, probably due to its content of N-acetyltryptophan.     

D-penicillamine decreases the H2O2 and phenylhydrazine induced lipid peroxidation in the erythrocyte membrane

The protecting effect of D-penicillamine against hydrogen peroxide and phenylhydrazine induced haemolysis and lipid peroxidation is discussed. It might represent a possible way of action of the drug in some neonatal disorders like hyperbilirubinaemia and retrolental fibroplasia.     

Effect of Sulfisoxazole on Bilirubin-Albumin Binding in Gunn Rats

Hyperbilirubinemic Gunn rats were used to study sulfisoxazole-mediated displacement of bilirubin from albumin. Bilirubin not bound to albumin or unbound bilirubin, which can enter the brain and cause damage, was measured by the automated peroxidase micromethod using the UB-Analyzer. When sulfisoxazole was added to the rat serum in vitro, it showed measurable displacing competition with bilirubin for the binding sites on albumin. The bilirubin titration curves of hyperbilirubinemic sera, after injection of sulfisoxazole, showed a shift to the left indicating that the drug effectively lowered the capacity of serum albumin to bind to bilirubin. The bilirubin binding affinity of the first binding site on the albumin decreased with the administration of 25 mg/kg or more of sulfixazole. The serum concentration of both total bilirubin and unbound bilirubin decreased after the injection of sulfisoxazole suggesting their diffusion into extravascular compartments.     

Neonatal bilirubin exposure and psychoeducational outcome

The association between neonatal bilirubin exposure and psychoeducational outcome was investigated in a group of grade school children 9 to 11 years old who required neonatal intensive care between 1977 and 1980. Seventy-four children were evaluated with four measures of psychoeducational outcome, including the Kaufman Mental Processing and Achievement Scales, the Beery Visual Motor Integration Test, and the Vineland Adaptive Behavior Scale. A measure of bilirubin binding calculated directly from the albumin concentration correlated significantly with the Kaufman Mental Processing Composite, although other more direct measures of bilirubin exposure (such as maximum serum bilirubin, direct measures of binding, and cumulative bilirubin exposure) did not. Thus, it is possible that the impact on psychoeducational outcome is the result of some other effect of low serum albumin itself, in addition to its ability to bind bilirubin. The correlation of the calculated albumin-determined binding value with the Kaufman Mental Processing Composite suggests that this level, rather than total serum bilirubin, may be more appropriate in determining clinical management.     

Perinatal asphyxia and jaundice in newborn infants

The serum bilirubin concentration was studied in 114 full term and 199 preterm babies suffering from either perinatal asphyxia or idiopathic indirect hyperbilirubinaemia, in order to establish the effect of asphyxia on the serum bilirubin level. Infants with any other disease causing non-physiologic jaundice were excluded. It was found that perinatal asphyxia per se does not exaggerate hyperbilirubinaemia either in full term or in preterm babies. Weight loss correlated significantly with the peak bilirubin concentration in all groups of patients. This would suggest the possible role of feeding and hydration in the genesis of hyperbilirubinaemia.     

Measurements of neonatal bilirubin and albumin concentrations: a need for improvement and quality control

Accurate and precise bilirubin and albumin measurements are essential for proper management of jaundiced neonates. Data hereon are lacking for Dutch laboratories. We aimed to determine variability of measurements of bilirubin and albumin concentrations typical for (preterm) neonates. Aqueous, human serum albumin-based samples with different concentrations of bilirubin (100, 200, 300, 400, and 500 μmol/L) and albumin (0, 10, 15, 20, 25, and 30 g/L) were sent to laboratories of all Dutch neonatal intensive care units (n = 10). Bilirubin and albumin recoveries of the specimens were measured using locally available routine analytical methods. The mean, standard deviation, and coefficients of variations (CV) were calculated per sample. Bilirubin concentrations were underestimated in the absence of albumin (maximal CV 26.0%). When the albumin concentration was 10 or 20 g/L, the bilirubin concentrations of the samples were overestimated (maximal CV 14.1% and 9.2%, respectively). Variability increased with higher weighed-in bilirubin concentrations. Measured albumin levels were ~10% lower than albumin levels of manufactured samples. Bilirubin concentration did not influence albumin measurements. The maximal CV was 6.8%. In conclusion, interlaboratory variability of bilirubin and albumin measurements is high. Recalibration and introduction of a specific quality assessment scheme for neonatal samples is recommended to ensure exchangeability of bilirubin and albumin measurements among laboratories and to control the observed large variability.     

Effect of a popular Chinese herb on neonatal bilirubin protein binding

A study on the effects of a popular Chinese herb commonly given to newborn infants was undertaken. 'Chuen-Lin', Coptis chinensus/japonicum, which is consumed by 28-51% of Chinese infants, was found to have a significant effect in displacing bilirubin from its serum protein binding as assessed by the peroxidase oxidation method. Taking this herbal tea may thus increase the risk of brain damage by free bilirubin in jaundiced infants. As neonatal hyperbilirubinaemia is highly prevalent among Southern Chinese, the use of Chuen-Lin in the perinatal period must be strongly discouraged.