Umbilical cord bilirubin as a predictor of neonatal jaundice: a retrospective cohort study

Prevalence and Risk Factors of Neonatal Hyperbilirubinemia in a Semi-Rural Area of the Democratic Republic of Congo: A Cohort Study

Neonatal hyperbilirubinemia (NH) is a frequent condition that, if left untreated, can lead to neurological disability and death. We assessed the prevalence of NH and associated neonatal and maternal risk factors in 362 mothers and 365 newborns in a semi-rural area of the Democratic Republic of Congo. In addition, we explored the knowledge and practices of mothers regarding this condition. We collected demographic data, anthropometric data, and obstetric and medical anamneses. We examined newborns at birth and at 24, 48, and 72 hours and measured bilirubin at birth in umbilical cord and capillary blood and thereafter in capillary blood. Hemoglobin, hematocrit, ABO group, Rhesus factor, glucose-6-phosphate dehydrogenase (G6PD) deficiency, Hemoglobin S (HbS), and malaria were assessed in mothers and newborns. Among 296 newborns (all time points available), 5.7% developed NH (95% CI: 3.4-9.0) between 24 and 72 hours according to National Institute for Health and Care Excellence (NICE) UK guidelines. There was a significantly higher risk in newborns with G6PD deficiency (homo- and hemizygous adjusted Odd Ratio [aOR]: 21.0, 95% CI: 4.1-105.9), preterm births (aOR: 6.1, 95% CI: 1.4-26.9), newborns with excessive birth weight loss (aOR: 5.8, 95% CI: 1.4-23.2), and hyperbilirubinemia at birth (aOR: 14.8, 95% CI: 2.7-79.6). Newborns with feto-maternal ABO incompatibility and G6PD deficiency had significantly higher bilirubin at birth than others. More than 60% of mothers had adequate knowledge of NH, but compliance with phototherapy in the absence of symptoms was low. Although risk factors for NH are common in this area, prevalence was not high, suggesting a need for better case definition. Implementation of point-of-care devices for diagnosis and awareness programs on risk prevention could help reduce neonatal morbidity and mortality associated with hyperbilirubinemia in these areas.

Diagnostic Accuracy of Cord Bilirubin to Predict the Need for Phototherapy in Healthy Neonates >35-Week Gestational Age: A Systematic Review and Meta-Analysis

Objective

Early discharge puts neonates at risk of delayed detection of jaundice and resulting neurological injury. In these neonates, we can use cord bilirubin to make predictions. In this meta-analysis, we assessed the diagnostic accuracy of cord bilirubin in predicting the need for phototherapy (AAP-2004 or NICE-2010 charts).

Methods

We searched the databases of PubMed, Embase, Cochrane Library, Google Scholar, and Index Medicus for Southeast Asian Region. We included all observational studies that assessed the diagnostic accuracy of cord bilirubin. A bivariate model was used to pool the data in prespecified range of cord bilirubin levels (<1.5 mg/dl, 1.5-2.0 mg/dl, 2.0-2.5 mg/dl, 2.5-3.0 mg/dl, and >3.0 mg/dl). Data were pooled separately for studies including all neonates (no risk stratification), high-risk neonates (Rh and/or ABO incompatibility only), and low-risk neonates (excluded Rh and ABO incompatibility).

Results

Of the 1990 unique records, we studied 153 full texts and included 54 studies in the meta-analysis. For all the three groups of studies, the highest diagnostic odds ratio was noted for a cord bilirubin cut-off of 2.5-3.0 mg/dl (all neonates: 22.5, 95% CI: 21.1, 22.9; high-risk neonates: 75.5, 95% CI: 63, 85.7; low-risk neonates: 91.9; 95% CI: 64, 134.14). Using the same cut-off, the studies including all neonates without risk stratification had a pooled sensitivity of 0.31 (95% CI: 0.18, 0.47) and a pooled specificity of 0.98 (0.96, 0.99) in predicting the need for phototherapy. In studies on high-risk neonates, the pooled sensitivity was 0.8 (0.39, 0.96) and pooled specificity was 0.95 (0.78, 0.99). In studies on low-risk neonates, the pooled sensitivity was 0.74 (0.39, 0.93) and pooled specificity of 0.97 (0.91, 0.99). We noted significant heterogeneity and a high risk of bias in the index test's conduct.

Conclusion

A cord bilirubin cut-off of 2.5-3 mg/dl has good diagnostic accuracy in predicting the need for phototherapy in neonates.

Registration number

CRD42020196216.

The predictive significance of umbilical cord bilirubin and bilirubin/albumin ratio for neonatal jaundice in healthy term newborns

BACKGROUND

The aim of this study is to determine the value of the questions asked in routine follow-up, the cord blood bilirubin (CBB) and bilirubin/albumin (B/A) ratio in estimating the risk of developing hyperbilirubinemia.

METHODS

Term and healthy 217 newborns whose CBB and albumin could be obtained and whose needed to be measured bilirubin level at the 24thand 72nd hours of life were included. Nutrition, sex and nationality, consanguinity between parents, jaundice in the sibling (s), mother's medications were questioned. CBB and albumin, serum total bilirubin (STB), serum albumin and transcutaneous bilirubin (TcB) at the 24th and 72nd hours of life, were recorded.

RESULTS

CBB and cord B/A ratio, STB and serum B/A ratio, and TcB at the 24th and 72nd hours were found to be higher in the babies who received the phototherapy (p < 0.001 for all). The moderate positive correlation (correlation coefficient 0.383) at the 24th hour and strong positive correlation (correlation coefficient 0.759) at the 72nd hour between STB and TcB measurements was detected. In estimating the need for phototherapy the sensitivity and specificity of CBB were 74.2% and 56.5%, the sensitivity and specifity of cord B/A was 74.2%, and 61.8%. The cut-off value of CBB in estimating the need for phototherapy is 1.8, and the cut-off value of the cord B/A ratio is 0.56. When the cut-off value is 1.8 for the CCB and the cord B/A ratio is 0.56, the positive predictive values are low, but the negative predictive values are significantly high (92.9% and 93.5%, respectively) in determining the need for phototherapy.

DISCUSSION

CBB and B/A ratio are important in predicting the possibility of indirect hyperbilirubinemia (IHB) development. Babies should be followed closely in terms of IHB development when their CBB value is 1.8 mg/dL and above, and the cord blood B/A ratio is 0.56 and above.

Immunohematology testing using umbilical cord blood: review of the literature, survey of practice and guidance development

BACKGROUND

Following delivery, blood tests are performed on umbilical cord blood (CB) to avoid neonatal venipuncture. Despite widespread and longstanding CB testing, no guidelines exist to suggest which immunohematology tests should be performed on CB.

STUDY DESIGN AND METHODS

We performed a scoping review, surveyed national practice, and developed guidance statements concerning CB testing. Database searches identified relevant articles. A survey was sent to all Canadian hospitals and transfusion laboratories that perform perinatal testing. A national panel of experts was convened to develop guidance statements.

RESULTS

A total of 116 articles met the inclusion criteria and were summarized. Literature on CB testing is limited; few studies have investigated laboratory testing methodologies or validated CB test results with peripheral samples. The survey was completed by 580/597 institutions (97%); 85% were community hospitals and 16% had a neonatal intensive care unit. There is diversity in the types of CB tests performed and variability in practice. While most centers order appropriately, some laboratories routinely perform CB tests that are not clinically indicated (e.g., direct antiglobulin testing for all neonates) and other do not perform CB tests when results would be beneficial (e.g., phenotype on CB when mother has a clinically significant antibody). Fifteen guidance statements were developed.

DISCUSSION

This study highlights variability in CB testing, likely reflecting evidence gaps, methodology differences between studies, and lack of guidelines. CB tests should only be performed when indicated and validated on this sample type. The presented guidance statements aim to standardize practice and encourage judicious CB sampling.

Cord blood bilirubin and prediction of neonatal hyperbilirubinemia and perinatal infection in newborns at risk of hemolysis

OBJECTIVE

To assess the accuracy of umbilical cord bilirubin values to predict jaundice in the first 48h of life and neonatal infection.

METHOD

Newborn infants treated at a regional well-baby nursery born at ≥36 weeks of gestation were included in this retrospective cohort study. All infants born in a 3-year period from mothers with O blood type and/or Rh-negative were included and had the umbilical cord bilirubin levels measured. Hyperbilirubinemia in the first 48h was defined as bilirubin levels above the phototherapy threshold. Neonatal infection was defined as any antibiotic treatment before discharge.

RESULTS

A total of 1360 newborn infants were included. Two hundred and three (14.9%) newborn infants developed hyperbilirubinemia in the first 48h of life. Hyperbilirubinemic infants had smaller birth weight, higher levels of umbilical cord bilirubin, a higher rate of infection and were more often direct antiglobulin test positive. Umbilical cord bilirubin had a sensitivity of 76.85% and a specificity of 69.58% in detecting hyperbilirubinemia in the first 48h, with the cut-off value at 34μmol/L. The area under the receiver operating characteristic curve was 0.80 (95% CI: 0.78-0.82). Umbilical cord bilirubin had a sensitivity of 27.03% and specificity of 91.31% in detecting perinatal infection. The area under the receiver operating characteristic (ROC) curve was 0.59 (95% CI: 0.57-0.63).

CONCLUSIONS

A positive correlation was found between umbilical cord bilirubin and hyperbilirubinemia in the first 48h of life. Umbilical cord bilirubin is a poor marker for predicting neonatal infection.

Rate and Predictors of Neonatal Jaundice in Northwest Ethiopia: Prospective Cohort Study

Background

Neonatal jaundice is one of the most common clinical disorders occurred worldwide. About 1.1 million neonates develop jaundice per year globally and the vast majority of them found in sub-Saharan Africa and South Asia. There is a paucity of evidence on the incidence rate and predictors of neonatal jaundice in Ethiopia. Therefore, this study was aimed at determining the rate and predictors of neonatal jaundice in the northwest, Ethiopia.

Methods

A prospective cohort study design was conducted at Debre Markos comprehensive, specialized Hospitals using 334 neonates from October 1, 2019, to June 30, 2020. Using a systematic random sampling technique, the study subjects were drawn. Data were entered into the Epi-Data^TM Version 4.2 and analyzed using STATA^TM Version 14.0. The Kaplan-Meier survival curve was used to estimate the survival time. A generalized Log rank test was used to compare the survival curves of different categorical variables. Finally, both bi-variable and multivariable Cox-proportional hazards regression models were used to identify the predictors of neonatal jaundice.

The Results

The overall incidence rate of jaundice among neonates was 4.5 per 100 person-hours. Long duration of labor [ARR = 3.5; 95% confidence interval (CI), (2.8–8.7)], being male neonates [ARR= 5.2; 95% CI (3.5–7.3)], “O” blood group mothers [ARR = 4.5; 95% CI (3.4–10.3)], and having neonatal sepsis 3.4 [ARR=3.4; 95% CI: (2.5–6.1)] were predictors.

Conclusion

The incidence rate of jaundice was higher in this study than the finding of the previous one. Being male, prolonged duration of labor, “O” blood group mothers and sepsis were the significant predictors. Hence, an effort has to be made to decrease the incidence rate of neonatal jaundice through improving newborn care and timely intervention for neonates with sepsis and delivered at a long duration of time as well as the neonates born from “o” blood type mothers are our recommendation.

An Automated Method for Direct Antiglobulin Testing and the Resulting Amount of Phototherapy Used at a Large Academic Medical Center

OBJECTIVE

To evaluate how clinical practice was affected by the change in direct antiglobulin testing (DAT) methodologies and subsequent stronger reported DAT results at our large academic medical center.

METHOD

We retrospectively reviewed DAT results of umbilical cord blood from infants with blood type A or B born to mothers with antibody-negative type O blood, based on records kept at the University of Alabama at Birmingham (UAB) Hospital, a 1400-bed academic medical center.

RESULTS

We randomly chose 50 neonates with positive DAT results who had been tested using the tube method and 50 whose testing had used the gel method. Although 86% of results with the tube method were positive microscopically, 52% and 40% of the DAT results with the gel method were 1+ and 2+ positive, respectively. Further, we observed an increase in the number of neonates treated with phototherapy who had been tested using the gel method.

CONCLUSION

We report that DATs performed using the gel method had increased DAT strength compared with tube testing, which led to increased use of phototherapy by our clinical colleagues.

Umbilical cord bilirubin level and pre-discharge hyperbilirubinemia risk

OBJECTIVES

To assess whether arterial umbilical cord bilirubin (aUCB) level at delivery predicts predischarge neonatal hyperbilirubinemia, facilitating a safe discharge from the hospital.

METHODS

Prospective analysis of hospital biochemistry records identified near term and term infants with recorded aUCB and predischarge, at 36 h of life, capillary heal bilirubin (cHB), to identify those with a cutoff of bilirubin levels >9 mg/ml, >75th percentile on the nomogram of Bhutani et al.

RESULTS

Of 616 study neonates, median (IQR) aUCB and cHB levels were 1.5 mg % (IQR 0.7-2.2) and 7.7 mg % (IQR 6.6-8.9), respectively. The values resulted statistically correlated (Pearson correlation coefficient 0.26, p < .0001) and an increment of 1 mg/dl in aUCB was associated with an increment (Regression coefficient, 95% confidence interval) of mean cHB 0.49 (0.33-0.65, p < .0001). Among these, 143 (23.2%) neonates developed bilirubin levels >9 mg/ml at 36 h of life and multivariable analysis confirmed that cHB levels (OR 1.49, 95% CI 1.22-1.82; p < .0001) and vaginal delivery (OR 2.34, 95% CI 1.33-4.36; p = .005) were significantly associated with bilirubin levels >9 mg/ml.

CONCLUSIONS

These data suggest that aUCB should be added to the list of major risk factors for neonatal hyperbilirubinemia.