Role of Erythrocyte Morphologic Features in Diagnosis of Neonatal Hemolytic Jaundice

Background: The most frequent complication needing re-hospitalization in the first week following birth is severe jaundice. Unfortunately, the majority of newborns with severe hyperbilirubinemia have no known underlying cause for their jaundice.
Aim of the Work: to diagnose the underlying causes of hemolysis by morphological abnormalities of erythrocytes in neonates with unconjugated hyperbilirubinemia.
Methods: This is a hospital based cross-sectional study included all neonates with unconjugated hyperbilirubinemia who admitted to the Neonatal Intensive Care Unit (NICU) of Pediatrics Department, Al-Azhar Assiut University Hospitals in the period from 1^st of November 2021 to 30^th of June 2022. All studied neonates were subjected to full-history taking and complete physical examinations. Laboratory evaluation included complete blood picture (CBC), blood smear and blood film, direct and indirect bilirubin, liver function test, and glucose-6-phosphate dehydrogenase (G6PD) quantitative test. In addition, maternal and neonatal blood groups, and direct antiglobulin (Coombs) test were also done. C-reactive protein (CRP), cerebrospinal fluid (CSF), thyroid function tests, ultrasonography and radiograms of the central nervous system were done to all cases.
Results:  A total of 50 neonates with confirmed diagnosis of hemolytic hyperbilirubinemia were included in the current study, with male:female ratio of 2.6:1. ABO incompatibility was the commonest cause of severe neonatal hyperbilirubinemia in 50.0% of the studied neonates, Rh incompatibility in 28.0%, Glucose 6-phosphate dehydrogenase (G6PD) deficiency in 12.0%, only two cases (4.0%) suffered from hereditary spherocytosis, while in  three cases we couldn’t detected the underlying cause of their hemolysis. More than half of the studied patients developed peak bilirubin at the 5^th postnatal day, 34% at the 2^nd postnatal day, five patients (10.0%) at the 1^st postnatal day, and two patients (4.0%) developed peak bilirubin at the 7^th postnatal day. The whole studied cases suffered from leucopenia, thrombocytosis, low hemoglobin level, low RBCs count, increased MCHC, decreased hematocrit value, and increase in the reticulocyte count. In addition, by examining the peripheral blood film of the studied neonates we observed that 26.0% suffered from abnormal blood film examination in the form of two cases (15.4%) with microspherocytes, 3 cases (23.1%) with elliptocytes, 6 cases (46.2%) with bite and blister cells, one case (7.7 %) with echinocytes, another one case (7.7 %) with schistocytes.
Conclusions: Applying morphological abnormalities of erythrocytes in routine clinical practice can help neonatologists to take care of neonates with hemolytic jaundice.