Serum Unconjugated Bilirubin Levels Research Articles

High-normal unconjugated bilirubin is associated with decreased risk of chronic kidney disease in type 2 diabetes: Areal-world study.

To investigate the association between serum unconjugated bilirubin (UCB) within normal limits and chronic kidney disease (CKD) in T2DM patients. This cross-sectional, real-world study was performed in 8661 hospitalised T2DM patients. The subjects were stratified into quintiles based on serum UCB levels. The clinical characteristics and CKD prevalence were compared among the UCB quantile groups. The associations of serum UCB levels and quintiles with CKD were also analysed by binary logistic regression. After controlling for age, sex, and diabetes duration (DD), the CKD prevalence (20.4%, 12.2%, 10.6%, 8.3%, and 6.4% for the first, second, third, fourth, and fifth quintiles, respectively, p<0.001 for trend) was significantly decreased across the serum UCB quintiles. The fully adjusted regression model showed negative associations of serum UCB levels (OR: 0.660, 95% CI: 0.585-0.744; p<0.001 for trend) and quintiles (p<0.001) with the presence of CKD. Compared with the subjects in the lowest UCB quintile, the risk of CKD decreased by 36.2%, 54.3%, 53.8%, and 62.1%, respectively, in those from the second to the highest UCB quintile. Additionally, C-reactive protein (CRP) levels were significantly higher in the subjects with CKD than in those without CKD (p<0.001), and significantly decreased across the UCB quintiles (p<0.001 for trend). Serum UCB levels within the normal range were significantly and negatively linked to CKD in T2DM patients. High-normal UCB may be an independent protective factor for CKD by its antioxidant and the following anti-inflammatory activities through its signalling activity, which was indicated by clearly decreased CRP levels across the UCB quintiles.

High-normal serum bilirubin decreased the risk of lower limb atherosclerosis in type 2 diabetes: a real-world study

BackgroundBilirubin has been found to protect against overt atherosclerotic diseases, but to date, few studies have investigated the effects of bilirubin especially within the normal range on lower limb atherosclerosis. Therefore, we aimed to assess the associations of bilirubin within normal limits including total bilirubin (TB), conjugated bilirubin (CB) and unconjugated bilirubin (UCB) with lower limb atherosclerosis in Chinese patients with type 2 diabetes mellitus (T2DM).Methods7284 T2DM patients with normal levels of serum bilirubin were included in this cross-sectional, real-world study. Patients were divided into quintiles by TB levels (< 8.7, 8.7-10.19, 10.20-11.99, 12-13.99, > 13.99 µmol/L). Lower limb ultrasonography was conducted to detect lower limb plaque and stenosis. The association between serum bilirubin and lower limb atherosclerosis was explored by multiple logistic regression.ResultsA remarkable decrease in the prevalence of lower limb plaque (77.5, 75.3, 70.7, 71.7 and 67.9%) and stenosis (21.1, 17.2, 13.3, 13.0 and 12.0%) was observed across the TB quintiles. Multivariable regression analysis showed that serum TB levels were negatively correlated with higher risks of lower limb plaque and stenosis, both as a continuous variable [OR (95%CI): 0.870 (0.784–0.964), p = 0.008 for plaque; and 0.835 (0.737–0.946), p = 0.005 for stenosis] and as categorized in quintiles (p = 0.015 and 0.016 for plaque and stenosis). Interestingly, serum CB levels were only negatively correlated with lower limb stenosis [OR (95%CI): 0.767 (0.685–0.858), p < 0.001], whereas serum UCB levels were only negatively associated with lower limb plaque [ OR (95%CI): 0.864 (0.784–0.952), p = 0.003] after a fully-adjusted analysis. Furthermore, serum CRP was significantly decreased across the TB quintiles and negatively associated with serum TB (r = -0.107, p < 0.001), CB (r = -0.054, p < 0.001), and UCB (r = -0.103, p < 0.001).ConclusionsHigh-normal serum bilirubin levels were independently and significantly related to reduced risks of lower limb atherosclerosis in T2DM patients. Furthermore, serum bilirubin levels including TB, CB and UCB were inversely correlated with CRP. These results suggested that higher-normal serum bilirubin may exhibit an anti-inflammatory and protective effect against lower limb atherosclerotic progression in T2DM subjects.

Low-normal serum unconjugated bilirubin levels are associated with late but not early carotid atherosclerotic lesions in T2DM subjects.

We aimed to examine the association of serum unconjugated bilirubin (UCB) within normal limits with carotid atherosclerosis in Chinese patients with type 2 diabetes mellitus (T2DM). This cross-sectional, real-world study was performed in 8,006 hospitalized T2DM patients including 4,153 men and 3,853 women with normal UCB. The subjects were stratified into quintiles based on serum UCB levels (<6.2, 6.2-7.9, 8.0-8.9, 9.0-10.9, and >10.9 μmol/l, respectively). Carotid atherosclerotic lesions detected by ultrasonography, including carotid intima-media thickness (CIMT), carotid plaque, and stenosis, were compared among the five groups. The associations of serum UCB levels and quintiles with carotid atherosclerotic lesions were also determined by multiple logistic regression. The prevalence of carotid plaque (55.3%, 49.5%, 47.4%, 43.8%, and 37.5%, respectively; p < 0.001 for trend) and stenosis (15.2%, 12.2%, 9.1%, 7.7%, and 5.4%, respectively; p < 0.001 for trend) was progressively lower across the UCB quintiles even after adjusting for age, sex, and duration of diabetes. Results of a fully adjusted multiple logistic regression analysis revealed that serum UCB levels and quintiles were significantly associated with carotid plaque and stenosis. Compared with the subjects in the lowest UCB quintile, the risk of carotid plaque decreased by 25.5%, 28.7%, 33.5%, and 42.8%, and that of carotid stenosis by 24.6%, 37.4%, 44.9%, and 47.3%, respectively, in those from the second to highest UCB quintiles. High serum UCB within the normal range was a protective factor against carotid plaque [odds ratio (OR) 0.810, 95% confidence interval (CI) 0.747-0.878; p < 0.001] and stenosis [OR 0.722, 95% CI 0.647-0.805; p < 0.001]. However, no significant association was observed between serum UCB and CIMT in T2DM patients. Furthermore, C-reactive protein (CRP) levels were significantly higher in the subjects with carotid atherosclerosis than in those without carotid atherosclerosis and clearly decreased across the UCB quintiles. Serum UCB within normal limits is inversely associated with late carotid atherosclerotic lesions including carotid plaque and stenosis but not CIMT, an early carotid atherosclerotic lesion in T2DM patients. High-normal UCB may be protective against carotid atherosclerosis by its anti-inflammation effect, which was indicated by significantly decreased CRP levels from the lowest to highest UCB quintiles.

Unconjugated hyperbilirubinemia may exacerbate certain underlying chronic liver diseases.

BACKGROUND: Negative correlations have been described between elevated serum unconjugated bilirubin levels and the prevalence/severity of various chronic inflammatory conditions. Whether a similar association exists for patients with unconjugated hyperbilirubinemia (UCB) and underlying chronic liver diseases (CLD) has yet to be reported. The aim of this study was to document hepatic necro-inflammatory disease activity and fibrosis in CLD patients with and without UCB and otherwise normal liver function tests (albumin and INR). METHODS: Necro-inflammatory disease activity was assessed by serum aminotransferase levels and fibrosis by APRI and FIB-4 calculations. UCB patients were matched 1:2 by age, gender, and underlying CLD to patients with normal bilirubin levels. RESULTS: From a database of 9,745 CLD patients, 208 (2.1%) had UCB and 399 served as matched controls. Overall, UCB patients had significantly higher serum aminotransferase levels, APRI, and FIB-4 scores. The differences were driven by patients with underlying chronic viral or immune mediated liver disorders rather than non-alcoholic fatty liver disease, alcohol-related liver disease, or 'other' CLDs. CONCLUSIONS: These results suggest UCB is associated with increased rather than decreased hepatic necro-inflammatory disease activity and fibrosis in patients with certain CLDs.

The Assessment of the Relationship among Bilirubin in Cord Blood and Venous Blood during the Intensive Care Unit Stay of Infants with Jaundice

Aim: Newborn babies who are released from the hospital at a younger postnatal age are more likely to be hospitalized to the nursery due to neonatal jaundice. This readmission is undoubtedly a significant source of strain in the nurseries, but it may be addressed by adequate assessment prior dismissing the newborn. The purpose of this study was to see if there was a link among cord blood bilirubin and vein bilirubin on the third day of life.&#x0D; Methods: On 120 healthy term newborns, a cross-sectional description research was conducted. Blood was drawn from the child's cord right after birth, whether vaginally or through caesarean surgery, for total serum bilirubin, unconjugated serum bilirubin levels, and conjugated serum bilirubin levels. On the third day (72 hours), a second serum blood sample is obtained from peripheral venous blood, and total serum bilirubin, unconjugated serum bilirubin, and conjugated serum bilirubin levels are measured again. The research was carried out over a one-year period, from March 2020 to February 2021.&#x0D; Results: The babies were divided into two groups: those with hyperbilirubinemia and those without. The findings acquired from aggregate and stratified samples demonstrate a significant association 0.542 and P-value 0.001 among serum cord blood bilirubin and peripheral venous blood bilirubin.&#x0D; Conclusion: There is a link among elevated bilirubin levels in normal infants born and serum cord blood bilirubin levels. The increase in serum cord blood bilirubin levels correlates with both the increase in peripheral venous blood bilirubin on the third day of life.

Oxidative Stress and Related Biomarkers in Gilbert's Syndrome: A Secondary Analysis of Two Case-Control Studies.

Bilirubin is an important antioxidant and a modulator of biological functions. However, most of the protection against oxidative stress was shown in vitro or ex vivo. The aim of this case-control study was to investigate whether subjects with Gilbert’s syndrome (GS) experience different levels of lipid and protein oxidation (as well as differences in oxidative stress related markers) compared to healthy controls. GS subjects (n = 119) demonstrated higher serum levels of unconjugated bilirubin (p < 0.001), a lower BMI (p < 0.001), 37% higher antioxidant potential assessed as ferric reducing ability potential (p < 0.001), higher advanced oxidation protein products (p < 0.01) andlower apolipoprotein B (p < 0.05), hs-C-reactive protein (p < 0.05), interleukin 6 (p < 0.001) and interleukin 1 beta (p < 0.05) values compared to healthy controls (n = 119). Furthermore, the resting heart rate was significantly lower in the GS group (p < 0.05). Stronger protective effects for GS subjects were demonstrated in the older subgroup (n = 104, average age 50 years) compared to those of the younger group (n = 134, average age 27 years). Although not all markers related to oxidative stress were different between the groups (e.g., malondialdehyde, homocysteine, oxLDL, and myeloperoxidase; p > 0.05), the observed differences contribute to the explanation of why GS serves as an important protector in the pathogenesis of metabolic, oxidative stress related diseases.

Yinzhihuang Oral Liquid Ameliorates Hyperbilirubinemia Induced by δ-Aminolevulinic Acid and Novobiocin in Neonatal Rats.

Yinzhihuang oral liquid (YZH) is a traditional Chinese medicine that has been widely used in Asia to prevent and treat neonatal hyperbilirubinemia, but the published preclinical studies on its anti-hyperbilirubinemia effect are conducted in adult animals, partly due to the lack of preclinical neonatal hyperbilirubinemia animal models. In the present study, we tested six reagents to induce hyperbilirubinemia in neonatal rats, and established two appropriate neonatal hyperbilirubinemia rat models by subcutaneous injection of δ-Aminolevulinic acid (ALA, 200 mg/kg) or novobiocin (NOVO, 200 mg/kg). Oral treatment of YZH (80, 160 and 320 mg/kg) significantly decreased serum conjugated bilirubin levels in ALA-treated neonatal rats and serum unconjugated bilirubin levels in NOVO-treated neonatal rats, respectively. Additionally, pre-treatment of YZH also prevented the increase of serum bilirubin levels in both ALA- and NOVO-treated rats. Mechanistically, YZH significantly up-regulated the mRNA expression of genes involved in hepatic bilirubin disposition (organic anion-transporting polypeptide 1b2, Oatp1b2; multidrug resistance-associated protein 2, Mrp2) and bilirubin conjugation (UDP-glucuronosyltransferase 1a1, Ugt1a1). Additionally, YZH up-regulated the mRNA expression of cytochrome P450 1A1 (Cyp1a1), the target gene of aryl hydrocarbon receptor (AhR), and increased the nuclear protein levels of AhR in livers of neonatal rats. YZH and its two active ingredients, namely baicalin (BCL) and 4'-hydroxyacetophenone (4-HT), up-regulated the mRNA expression of AhR target genes (CYP1A1 and UGT1A1) and increased nuclear protein levels of AhR in HepG2 cells. In conclusion, the present study provides two neonatal hyperbilirubinemia animal models and evaluates the anti-hyperbilirubinemia effect and mechanisms of YZH in neonatal animals.

Low Serum Levels of Fibroblast Growth Factor 2 in Gunn Rats: A Hyperbilirubinemia Animal Model of Schizophrenic Symptoms.

Fibroblast Growth Factor (FGF) 2 (also referred to as basic FGF) is a multifunctional growth factor that plays a pivotal role in the pro-survival, pro-migration and prodifferentiation of neurons. Because alterations in FGF2 levels are suggested to contribute to the pathogenesis of schizophrenia, we investigated serum levels of FGF2 in the Gunn rat, a hyperbilirubinemia animal model of schizophrenic symptoms. The enzyme-linked immunosorbent assay showed that the serum levels of FGF2 in Gunn rats were 5.09 ± 0.236 pg/mL, while those in the normal strain Wistar rats, serum levels were 11.90 ± 2.142 pg/mL. The serum FGF2 levels in Gunn rats were significantly lower than those in Wistar rats. We also measured serum levels of Unconjugated Bilirubin (UCB) and found a significant negative correlation between UCB and FGF2 in terms of serum levels in all the rats studied. Since it is known that FGF2 regulates dopaminergic neurons and have antineuroinflammatory effects, our finding suggests that low FGF2 levels may contribute to the pathogenesis of schizophrenia, in which imbalanced dopamin-ergic signaling and neuroinflammation are supposed to play certain roles.

Oxidative state in equine neonates: Anti- and pro-oxidants.

In newborns, exposure to the extrauterine environment with high oxygen tension and sudden pulmonary adaptation leads to an increase in reactive oxygen species (ROS). ROS have several physiological roles, which are essential for neonatal development, however, when unbalanced, these highly unstable molecules can cause cellular destabilisation, compromising vital processes. To characterise the oxidative status in healthy equine neonates, evaluating an indicator of lipid peroxidation and both enzymatic and nonenzymatic antioxidant systems, during the first week of life. Experimental cohort. Twenty-four foals were evaluated, with blood collections performed at 5minutes, 12, 72 and 168hours after birth. The degree of lipid peroxidation was quantified using Thiobarbituric Acid Reactive Substances (TBARS). Superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzymatic activities, and total, conjugated and unconjugated serum bilirubin levels were also analysed. Comparisons were performed using ANOVA followed by a Tukey's test. Additionally, dependent variables were also evaluated with Pearson's correlation tests. Higher GPx activity was observed at 12 and 72hours when compared to 5minutes. An increase in TBARS levels was found at 5minutes after birth, followed by a decrease at 72hours and stabilisation through subsequent moments until 168hours after birth. No differences were observed in SOD activity when comparing the four time points. Bilirubin concentrations were lower at 5minutes after birth and total and unconjugated bilirubin increased at 12hours and decreased between 72 and 168hours after birth. Lipid peroxidation at birth was high, suggesting an increase in ROS levels relating to physiological events in neonatal adaptation. Antioxidant systems, involving unconjugated bilirubin and GPx, were activated and these biomolecules act concomitantly to reduce ROS levels, thus maintaining oxidative homeostasis. Overall, our results suggest a pro-oxidant balance during the first 168hours after birth in equine neonates.

Role of cord blood bilirubin and albumin levels as predictors of subsequent hyperbilirubinemia in newborns

Introduction: Neonatal hyperbilirubinemia is one of the most common problems in term and preterm babies. Development of hyperbilirubinemia in neonates is fretful for the parents and a concern for the pediatrician too. Healthy babies born through normal vaginal delivery who are getting discharged early are being readmitted for the treatment of hyperbilirubinemia. Aim sand Objectives: The present study is done to determine the correlation of cord blood bilirubin, albumin and neonatal hyperbilirubinemia in identifying newborn babies at risk of developing significant hyperbilirubinemia and to establish the cutoff values of cord blood bilirubin and cord blood albumin levels to identify such high-risk neonates. Materials and Methods: In present study, 303 term neonates who are delivered in ASRAM, Eluru from January 2012-January 2013, were included after parental consent. Cord blood bilirubin, Blood grouping and typing, Cord blood albumin and serum bilirubin levels were done in all babies. Results: The incidence of significant hyperbilirubinemia in this study was 23.7%. Cord serum unconjugated bilirubin level ≥2.0 mg/dl and total cordserum bilirubin level ≥ 2.5mg/dl as high risk indicator towards predicting neonatal hyperbilirubinemia in first week of life. 58.53% babies had cord serum albumin level &lt; 2.8gm/dl. Conclusion: Cord serum unconjugated bilirubin level ≥2mg/dl and total cord serum bilirubin level ≥2.5mg/dl, cord blood albumin &lt;2.8g/dl is a high-risk indicator towards predicting neonatal hyperbilirubinemia in the first week of life.

Biliverdin Reductase inhibitors did not improve severe unconjugated hyperbilirubinemia in vivo

We aimed to identify potent biliverdin reductase (BVRA) inhibitors as a novel concept for the treatment of severe unconjugated hyperbilirubinemia. 1280 FDA-approved compounds were screened in vitro for their ability to inhibit human and rat BVRA activity and 26 compounds were identified as BVRA inhibitors. Montelukast and Disulfiram were selected as potentially clinically applicable drugs and tested to reduce serum unconjugated bilirubin (UCB) levels in the Ugt1a1-deficient rat, a model for chronic unconjugated hyperbilirubinemia. Oral administration of Disulfiram was toxic in the Ugt1a1-deficient rat (weight loss, transaminase elevation). Oral Montelukast administration led to low serum concentrations and did not alter serum UCB levels. Intraperitoneal injections of Montelukast resulted in concentrations up to 110 μmol/L in serum and 400 μmol/L in the liver. Still, serum UCB levels remained unaltered. This first study on biliverdin reductase inhibition as a novel concept for treatment of unconjugated hyperbilirubinemia identified putative in vitro BVRA inhibitors. Montelukast, the clinically most suitable inhibitor, did not result in reduction of serum UCB in the Ugt1a1-deficient rat. The proposed treatment strategy will not result in amelioration of severe unconjugated hyperbilirubinemia in humans without the identification or development of more potent BVRA inhibitors.

Bilirubin and Atherosclerotic Diseases

Bilirubin is the final product of heme catabolism in the systemic circulation. For decades, increased serum/plasma bilirubin levels were considered an ominous sign of an underlying liver disease. However, data from recent years convincingly suggest that mildly elevated bilirubin concentrations are associated with protection against various oxidative stress-mediated diseases, atherosclerotic conditions being the most clinically relevant. Although scarce data on beneficial effects of bilirubin had been published also in the past, it took until 1994 when the first clinical study demonstrated an increased risk of coronary heart disease in subjects with low serum bilirubin levels, and bilirubin was found to be a risk factor for atherosclerotic diseases independent of standard risk factors. Consistent with these results, we proved in our own studies, that subjects with mild elevation of serum levels of unconjugated bilirubin (benign hyperbilirubinemia, Gilbert syndrome) have much lower prevalence/incidence of coronary heart as well as peripheral vascular disease. We have also demonstrated that this association is even more general, with serum bilirubin being a biomarker of numerous other diseases, often associated with increased risk of atherosclerosis. In addition, very recent data have demonstrated biological pathways modulated by bilirubin, which are responsible for observed strong clinical associations.

Fluorescent protein-based detection of unconjugated bilirubin in newborn serum.

Increased serum levels of unconjugated bilirubin are associated with the development of brain damage in newborns. In current clinical settings, there are no methods for directly determining serum levels of unconjugated bilirubin. UnaG, a fluorescent protein from Japanese eel muscle that specifically binds to unconjugated bilirubin was used in this study. Linear regression analysis was carried out to compare unconjugated bilirubin levels measured by UnaG and conventional bilirubin oxidase methods. Unconjugated bilirubin levels in the serum of newborns who were untreated or treated with phototherapy were compared. Effects of interfering factors in the serum (conjugated bilirubin, hemoglobin, and lipid) on unconjugated bilirubin concentration measured by the UnaG method were also evaluated. Unconjugated bilirubin levels measured by the UnaG method were highly correlated with those determined by the bilirubin oxidase assay. Unconjugated bilirubin levels determined by bilirubin oxidase and UnaG assays were similar in serum samples containing conjugated bilirubin. The performance of the UnaG assay was unaffected by phototherapy and the presence of serum hemoglobin and lipid emulsion. These results demonstrate the clinical applicability of the UnaG method for direct measurement of unconjugated bilirubin levels in newborn serum.

Cardiovascular changes in patients with non-severe Plasmodium vivax malaria

BackgroundCardiovascular system involvement in patients with Plasmodium vivax malaria has been poorly addressed. The aim of this study was to evaluate cardiac structures and function, and serum markers of cardiovascular injury in patients with the non-severe form of vivax malaria in Manaus, Amazonas State, Brazil. Methods and resultsWe prospectively evaluated 26 patients with vivax malaria in an outpatient referral hospital and compared results with a control group of 25 gender- and age-matched healthy individuals. Patients underwent clinical evaluation, laboratory tests, and transthoracic echocardiography at first evaluation (day zero, D0) and seven days (D7) after malaria diagnosis. At D0 echocardiography showed higher left ventricular (LV) systolic diameter (28.8±2.82 vs 30.9±4.03mm; p=0.037) and LV diastolic volume (82.4±12.3 vs 93.8±25.9ml; p=0.05), and lower LV ejection fraction (Teicholz method: 73.2±6.59 vs 68.4±4.87%; p=0.004) in patients compared to controls. Right ventricle (RV) fractional area change (54.7±5.11 vs 50.5±6.71%; p=0.014) was lower, and RV myocardial performance index (0.21±0.07 vs 0.33±0.19; p=0.007), and pulmonary vascular resistance (1.13±0.25 vs 1.32±0.26 Woods unit; p=0.012) were higher in patients than controls. Patients presented higher serum levels of unconjugated bilirubin (0.24±0.15 vs 1.30±0.89mg/dL; p<0.001), soluble vascular cell adhesion molecule–1 (sVCAM-1; 453±143 vs 1983±880ng/mL; p<0.001), N-terminal prohormone brain natriuretic peptide (0.59±0.86 vs 1.08±0.81pg/mL; p=0.045), and troponin T (861±338 vs 1037±264pg/mL; p=0.045), and lower levels of plasma nitrite (13.42±8.15 vs 8.98±3.97μM; p=0.016) than controls. Most alterations had reversed by D7. ConclusionPatients with non-severe Plasmodium vivax malaria present subclinical reversible cardiovascular changes.

Unconjugated bilirubin inhibits proteolytic cleavage of von Willebrand factor by ADAMTS13 protease

Bilirubin is a yellow breakdown product of heme catabolism. Increased serum levels of unconjugated bilirubin are conditions commonly seen in premature neonates and adults with acute hemolysis including thrombotic microangiopathy. Previous studies have shown that unconjugated bilirubin lowers plasma ADAMTS13 activity, but the mechanism is not fully understood. The study is to determine whether unconjugated bilirubin directly inhibits the cleavage of von Willebrand factor (VWF) and its analogs by ADAMTS13. Fluorogenic, surface-enhanced laser desorption/ionization time-of-flight mass spectrometric assay, and Western blotting analyses were used to address this question. Unconjugated bilirubin inhibits the cleavage of F485-rVWF73-H, D633-rVWF73-H, and GST-rVWF71-11K by ADAMTS13 in a concentration-dependent manner with a half-maximal inhibitory concentration of ~13, ~70, and ~17 μmol L(-1) , respectively. Unconjugated bilirubin also dose-dependently inhibits the cleavage of multimeric VWF by ADAMTS13 under denaturing conditions. The inhibitory activity of bilirubin on the cleavage of D633-rVWF73-H and multimeric VWF, but not F485-rVWF73-H, was eliminated after incubation with bilirubin oxidase that converts bilirubin to biliverdin. Furthermore, plasma ADAMTS13 activity in patients with hyperbilirubinemia increased after treatment with bilirubin oxidase. Unconjugated bilirubin directly inhibits ADAMTS13's ability to cleave both peptidyl and native VWF substrates in addition to its interference with certain fluorogenic assays. Our findings may help proper interpretation of ADAMTS13 results under pathological conditions. Whether elevated serum unconjugated bilirubin has prothrombotic effect in vivo remains to be determined in our future study.

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Cochrane Review: Prophylactic phototherapy for preventing jaundice in preterm or low birth weight infants

Low birth weight and premature infants are at major risk for exaggerated hyperbilirubinaemia and jaundice that can lead to bilirubin encephalopathy. Phototherapy is the most common treatment for neonatal hyperbilirubinaemia and could be most effective in preventing the sequelae of hyperbilirubinaemia if initiated prophylactically. To evaluate the efficacy and safety of prophylactic phototherapy for preterm (< 37 weeks gestational age) or low birth weight infants (birth weight < 2500 g). We searched the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 3) on 31 March 2011, MEDLINE (1950 to 31 March 2011), EMBASE (1980 to 31 March 2011) and CINAHL (1982 to 31 March 2011). Randomised controlled trials or quasi-randomised controlled studies evaluating the effects of prophylactic phototherapy for preterm or low birth weight infants. Two authors independently obtained data from published articles. We performed fixed-effect meta-analysis for the outcomes: rate of exchange transfusion, cerebral palsy or other neurodevelopmental impairment, peak serum bilirubin level and all-cause mortality. Nine studies of 3449 participants were included. The rate of exchange transfusion was reduced in one study with liberal transfusion criteria (risk ratio (RR) 0.20; 95% confidence interval (CI) 0.13 to 0.31) but not in the other two more recent studies with stringent criteria (typical RR 0.66; 95% CI 0.19 to 2.28). There was no statistically significant difference in the rate of cerebral palsy (typical RR 0.96; 95% CI 0.50 to 1.85; two studies, 756 participants). However, one large study that reported on neurodevelopmental impairment (a composite outcome including cerebral palsy) found a slightly lower rate of neurodevelopmental impairment with prophylactic phototherapy (RR 0.85; 95% CI 0.74 to 0.99; 1804 participants). The prophylactic phototherapy group had lower peak bilirubin levels (mean difference (MD) -2.73; 95% CI -2.89 to -2.57; six studies, 2319 participants) and had fewer neonates with peak unconjugated serum bilirubin levels > 10 mg/dl (typical RR 0.27; 95% CI 0.22 to 0.33; three studies, 1090 participants) or peak unconjugated serum bilirubin levels > 15 mg/dl (typical RR 0.13; 95% CI 0.07 to 0.23; four studies, 1116 participants). There was no statistically significant difference in the rate of all-cause mortality between the two groups (typical RR 1.08; 95% CI 0.93 to 1.26; four studies, 3044 participants). Prophylactic phototherapy helps to maintain a lower serum bilirubin concentration and may have an effect on the rate of exchange transfusion and the risk of neurodevelopmental impairment. However, further well-designed studies are needed to determine the efficacy and safety of prophylactic phototherapy on long-term outcomes including neurodevelopmental outcomes.

Unconjugated hyperbilirubinemia is inversely associated with non‐alcoholic steatohepatitis (NASH)

It has been recognised that unconjugated bilirubin contains hepatic anti-fibrogenic and anti-inflammatory properties and is a potent physiological antioxidant cytoprotectant. We believe that unconjugated hyperbilirubinemia may protect against development of non-alcoholic steatohepatitis (NASH). This study was conducted to assess the association of serum unconjugated bilirubin levels and histological liver damage in non-alcoholic fatty liver disease (NAFLD). This was a retrospective analysis involving adult patients from a tertiary medical centre undergoing liver biopsy to evaluate suspected NAFLD or NASH and a control group without NAFLD based on normal liver ultrasound, labs and history. Identification of unconjugated hyperbilirubinemia was based on the presence of predominantly unconjugated bilirubin ≥1.0 mg/dL (17.1 μmol/L) while fasting, in the absence of haemolytic disease or other hepatic function alteration. Six-hundred and forty-one patients were included. Unconjugated hyperbilirubinemia was inversely associated with NASH (OR 16.1, 95% CI 3.7-70.8 P < 0.001). Of the patients without NAFLD (133 patients), 13 (9.8%) had unconjugated hyperbilirubinemia (range 1.0-1.8, mean 1.4). Of the patients with NAFLD without NASH (285 patients), 32 (11.2%) had unconjugated hyperbilirubinemia (range 1.0-3.0, mean 1.4). Of the patients with NASH (223 patients), three (1.3%) had unconjugated hyperbilirubinemia (1.0, 1.1, 1.4). Unconjugated hyperbilirubinemia is inversely associated with the histopathological severity of liver damage in non-alcoholic fatty liver disease.

Hyperbilirubinemia and Neurodevelopmental Outcome of Very Low Birthweight Infants: Results from the LIFT Cohort

BackgroundBilirubin-related neurotoxicity is an important clinical issue in very low birthweight (VLBW) infants, and the existing literature is inconsistent.ObjectiveTo analyze the relationship between maximal serum unconjugated bilirubin levels (SBL) and neurodevelopmental outcome at 2-year corrected age in VLBW infants.MethodsPhototherapy was initiated in all infants born before 33 weeks of gestation, according to Maisels' recommendations. Neurodevelopmental assessment at 2-year corrected age was performed in all infants that survived. SBLs collected during the first week of life were used to define three tertiles of max-SBL. The first tertile corresponded to infants with the lowest max-SBL.Results and ConclusionsA total of 724 infants were included in the study, and among them, 631 (87%) were evaluated at two years old. The infants of the first tertile were younger and smaller than the infants of the other two tertiles, in accordance with Maisels' recommendations for very small infants. No difference in the risk of impaired functional outcome among the three groups was observed. However, among infants weighing less than 1001 g, those in the third tertile had a poorer neurodevelopmental prognosis as compared to those in the second tertile (adjusted odds ratio = 6.8, 95% CI: 1.2–36.7, p = 0.03). Considering the results obtained, we propose 196 µmol/L (11.5 mg/dL) when birthweight varies between 1001 and 1500 g, and 170 µmol/L (9.9 mg/dL) when birthweight is less than 1001 g, as recommended max-SBLs (defined as maximal levels of 95th percentile curves of SBLs in infants with an optimal outcome). When Maisels' recommendations were applied, max SBLs were higher in 8% of infants weighing 1001–1500 g and in 15% of infants weighing less than 1001 g. Our data seems to validate Maisels' recommendations in the overall population of infants born before 33 weeks of gestation, but not in infants weighing less than 1001 g.

Prophylactic phototherapy for preventing jaundice in preterm or low birth weight infants

Low birth weight and premature infants are at major risk for exaggerated hyperbilirubinaemia and jaundice that can lead to bilirubin encephalopathy. Phototherapy is the most common treatment for neonatal hyperbilirubinaemia and could be most effective in preventing the sequelae of hyperbilirubinaemia if initiated prophylactically. To evaluate the efficacy and safety of prophylactic phototherapy for preterm (< 37 weeks gestational age) or low birth weight infants (birth weight < 2500 g). We searched the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 3) on 31 March 2011,MEDLINE (1950 to 31 March 2011), EMBASE (1980 to 31 March 2011) and CINAHL (1982 to 31 March 2011). Randomised controlled trials or quasi-randomised controlled studiesevaluating the effects of prophylactic phototherapy for preterm or low birth weight infants. Two authors independently obtained data from published articles. We performed fixed-effect meta-analysis for the outcomes: rate of exchange transfusion, cerebral palsy or other neurodevelopmental impairment, peak serum bilirubin level and all-cause mortality. Nine studies of 3449 participants were included. The rate of exchange transfusion was reduced in one study with liberal transfusion criteria (risk ratio (RR) 0.20; 95% confidence interval (CI) 0.13 to 0.31) but not in the other two more recent studies with stringent criteria (typical RR 0.66; 95% CI 0.19 to 2.28). There was no statistically significant difference in the rate of cerebral palsy (typical RR 0.96; 95% CI 0.50 to 1.85; two studies, 756 participants). However, one large study that reported on neurodevelopmental impairment (a composite outcome including cerebral palsy) found a slightly lower rate of neurodevelopmental impairment with prophylactic phototherapy (RR 0.85; 95% CI 0.74 to 0.99; 1804 participants). The prophylactic phototherapy group had lower peak bilirubin levels (mean difference (MD) -2.73; 95% CI -2.89 to -2.57; six studies, 2319 participants) and had fewer neonates with peak unconjugated serum bilirubin levels > 10 mg/dl (typical RR 0.27; 95% CI 0.22 to 0.33; three studies, 1090 participants) or peak unconjugated serum bilirubin levels > 15 mg/dl (typical RR 0.13; 95% CI 0.07 to 0.23; four studies, 1116 participants). There was no statistically significant difference in the rate of all-cause mortality between the two groups (typical RR 1.08; 95% CI 0.93 to 1.26; four studies, 3044 participants). Prophylactic phototherapy helps to maintain a lower serum bilirubin concentration and may have an effect on the rate of exchange transfusion and the risk of neurodevelopmental impairment. However, further well-designed studies are needed to determine the efficacy and safety of prophylactic phototherapy on long-term outcomes including neurodevelopmental outcomes.