BACKGROUND: Neonatal jaundice that occurs in ABO or Rhesus issoimunisation has been recognized as one of the major risk factors for development of severe hyperbilirubinemia and bilirubin neurotoxicity.AIM: Aim of our study was to investigate clinical and laboratory parameters associated with hemolytic jaundice due to Rh and ABO incompatibility and compare results with the group of unspecific jaundice.MATERIAL AND METHODS: One hundred sixty seven (167) neonatal hyperbilirubinemia cases were included in the study, 24.6% of which presented with ABO/Rhesus type hemolytic jaundice, and the rest with unspecific jaundice. Evaluation included: blood count, reticulocites, serum bilirubin, aminotransferases, blood grouping, and Coombs test, also the day of bilirubin peak, duration of the hyperbilirubinemia, and additional bilirubin measurements.RESULTS: We showed significantly lower mean values of hemoglobin, erythrocytes and hematocrit and significantly higher values of reticulocytes in the group of ABO/Rh incompatibility compared to the group of jaundice of unspecific etiology; also an earlier presentation and a higher-grade jaundice in this group.CONCLUSIONS: The laboratory profile in ABO/Rh isoimmunisation cases depicts hemolytic mechanism of jaundice. These cases carry a significant risk for early and severe hyperbilirubinemia and are eligible for neurodevelopmental follow-up. Hematological parameters and blood grouping are simple diagnostic methods that assist the etiological diagnosis of neonatal hyperbilirubinemia.

Neonatal hyperbilirubinemia is a common clinical manifestation of the inherited glucose-6-phosphate dehydrogenase (G6PD) deficiency. The aim of this study was to investigate the influence of the inherited G6PD deficiency on the appearance of neonatal hyperbilirubinemia in southern Croatia. The fluorescent spot test (FST) was used in a retrospective study to screen blood samples of 513 male children who had neonatal hyperbilirubinemia, of unknown cause, higher than 240 μmol/L. Fluorescence readings were performed at the beginning and at the fifth and tenth minute of incubation and were classified into three groups bright fluorescence (BF), weak fluorescence (WF) and no fluorescence (NF). Normal samples show bright fluorescence. All NF and WF samples at the fifth minute were quantitatively measured using the spectrophotometric method. Bright fluorescence was present in 461 patients (89.9%) at the fifth minute. The remaining 52 (10.1%) were quantitatively estimated using the spectrophotometric method. G6PD deficiency was observed in 38 patients (7.4%). Prevalence rate of G6PD deficiency among male newborns with hyperbilirubinemia in southern Croatia is significantly higher (p < 0.01) compared with the previously reported prevalence rate among male in general population of southern Croatia (0.75%). We recommend FST to be performed in hyperbilirubinemic newborns in southern Croatia.

Glucose-6-phospahte dehydrogenase deficiency (G6PD) is one of the most common inherited disorders affecting around 400 million people worldwide. Molecular analysis of the G6PD gene identified more than 140 distinct mutations, the majority being single base missense mutations. G6PD Mediterranean is the most common variant found in populations of the Mediterranean area. The aim of our study was to perform molecular characterization of G6PD deficiency in families from the Republic of Macedonia and correlate the findings to disease phenotype. Six patients and seven other family members were selected for genetic characterization, the selection procedure involved clinical evaluation and G6PD quantitative testing. All patients were first screened for the Mediterranean mutation, and subsequently for the Seattle mutation. Mutations were detected using PCR amplification and appropriate restriction endonuclease cleavage. Four hemizygote and 3 heterozygous carriers for G6PD Mediterranean were detected. All G6PD deficient patients from this group showed clinical picture of hemolysis, and in 66.6% neonatal jaundice was confirmed based on history data. To our knowledge, this is the first study concerned with molecular aspects of the G6PD deficiency in R. Macedonia. This study represents a step towards a more comprehensive genetic evaluation in our population and better understanding of the health issues involved.

Neonatal indirect hyperbilirubinemia is one of the most frequent neonatal problems that affect almost two thirds of term infants. Although etiology of jaundice has been widely studied, identification of pathological causes presents constant clinical challenge. Our study group performed an extensive retrospective study of etiology of neonatal hyperbilirubinemia and showed high frequency (44.37%) of jaundice of undefined etiology. The group included exaggerated physiological jaundice, early- and late-onset breast-milk jaundice, and no identifiable etiology. Other etiologies were neonatal infection, prematurity, birth trauma, and hemolysis represented with 15%. We described hematological parameters in both non-hemolytic and hemolytic type of jaundice; a significant correlation of relevant laboratory findings with etiology was established. In this chapter we will present our own data and perform a data-relevant literature review. Furthermore, investigation and management plan of neonatal indirect hyperbilirubinemia will be presented in accordance with own data and available literature.

The aim of this study is to investigate the frequency of six tag SNPs (single nucleotide polymorphisms) within specific genes (F2, F5, F7, MTHFR, NOS2A, PAI 2-1, PAI 2-2, and PAI 3-3): F2 (rs1799963), F5 (rs6025), F7 (rs6046), NOS 2 (rs1137933), PAI 2 (SERPINB2) (rs6103), MTHFR (rs1801133). The study also investigates their association with the development and severity of HIE. The genes F2, F5, and F7 code for proteins involved in blood clotting. MTHFR is a gene that plays a significant role in processing amino acids, the fundamental building blocks of proteins. NOS2A, PAI 2-1, PAI 2-2, and PAI 3-3 are genes involved in the regulation of various physiological processes, such as the relaxation of smooth muscle, regulation of central blood pressure, vasodilatation, and synaptic plasticity. Changes in these genes may be associated with brain injury. This retrospective study included 279 participants, of which 132 participants had Hypoxic–Ischemic Encephalopathy (HIE) and 147 subjects were in the control group. Our study found that certain genetic variants in the rs61103 and rs1137933 polymorphisms were associated with hypoxic–ischemic encephalopathy (HIE) and the findings of the magnetic resonance imaging. There was a correlation between Apgar scores and the degree of damage according to the ultrasound findings. These results highlight the complex relationship between genetic factors, clinical parameters, and the severity of HIE.