الفهرس 
Neonatal JaundiceOnly 14 pages are availabe for public view
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Abstract
Bilirubin neurotoxicity (kernicterus) occurs because of neural damage of certain brain areas. Clinical spectrum of kernicterus ranges from mild symptoms to very severe manifestations.
Several mechanisms are involved in bilirubin induced neurotoxicity. One of proposed mechanisms is bilirubin-induced lipid peroxidation resulting in over production of prostaglandins and neuroinflammation.
Our study aimed to: Study the effect of hyperbilirubinemia on blood levels of oxidant and total antioxidant and their relationship with early manifestations of kernicterus. Study the effect of phototherapy on blood levels of oxidant and total antioxidant. Study the relation between blood levels of oxidant and total antioxidant and the cause of jaundice.
Patients and Methods
We conducted a prospective observational study on 104 full term newborns, admitted to Neonatal Intensive Care Unit of Menoufia University Hospitals, in the period from July 2019 to June 2020.
Our study included a total of (104) full-term newborns, classified into two groups, case group (group I) that included 52 newborns with indirect hyperbilirubinemia requiring phototherapy according to American Academy of Pediatrics guidelines and a control group (group II) which included 52 healthy full-term newborns without hyperbilirubinemia.
On admission all newborns were subjected to full history taking, clinical examination, neurological examination and laboratory including investigations plasma level of Prostaglandin E2 (PGE2), Prostaglandin Em (PGEm), Malondialdehyde (MDA) and Total antioxidant (TAO). In addition, chest x- ray if needed and brain MRI for suspected cases of kernicterus.
According to the aim of our study we classified newborns into two groups,
i. group I (n=52) We measured plasma PGE2, PGEm, MDA and TAO levels before and after phototherapy.
group I was further subdivided into:
group I a (n=12)
group I b (n=40)
ii. group II (n=52) in these newborns we measured plasma levels of PGE2, PGEm, MDA and total TAO only one time.
Summary
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Results
The study has shown that:
There was a significant difference observed between both subgroups regarding mean of duration of phototherapy (114.5±24.37; p<0.032) that was higher in subgroup I a.
At the time of admission, means of total serum bilirubin (TSB), direct serum bilirubin (DSB), MDA, PGEm (16.63±3.73, 1.21±0.59, 8.18±1.86 and 37.47±23.63) respectively were significantly higher in group I (before phototherapy) compared to group II, (p < 0.0001).
Means of TAO (0.811±0.09) was significantly lower in group I (before phototherapy) compared to group II, (p<0.0001).
Before phototherapy in subgroup I a and subgroup I b, there were significant differences in the plasma levels of PGEm, PGE2 and TSB, that were higher in subgroup I a (54.39±36.99; p<0.019), (59.25±42.41; p<0.019), (21.66±2.67; p<0.006) respectively.
Means of plasma level of TSB, DSB, MDA, PGE2 and PGEm (16.63±3.73, 1.21±0.59, 8.18±1.86, 81.09±23.92 and 37.47±23.63) respectively were significantly higher in group I (before phototherapy) compared to their levels (after phototherapy) (p<0.0001).
Mean of TAO (0.811±0.09) was significantly lower in group I (before phototherapy) compared to its level after phototherapy (p< 0.0001).
After phototherapy in subgroup I a and subgroup I b, there were significant differences in the levels of PGEm, DSB and TSB that were higher in subgroup I a (31.18±8.90; p<0.02), (0.667±0.20, p<0.001) and (10.07±0.66, p<0.001) respectively.
Patients with PGE2 more than 43.37 were more likely to have kernicterus, as 66.7% of them were truly diagnosed as kernicterus (sensitivity). The proportion of actual negatives that were correctly identified as negative PGE2 (less than 43.37) was 85% (specificity).
PGE2 can separate well the tested group into those who was diagnosed as having kernicterus or not.
Conclusions
Hyperbilirubinemia has effects on blood levels of oxidants and antioxidants:
Positive correlation with PGE2, PGEm and MDA.
Negative correlation with TAO.
Regarding kernicterus:
PGE2 is a reliable biomarker at cutoff point 43.37 ng/l in exclusion of kernicterus in jaundiced newborns (specificity 85%).
PGEm at cutoff point 33.34 ng/l is a reliable biomarker in diagnosis of kernicterus (sensitivity 67%).
Summary
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Regarding phototherapy:
MDA has significant positive correlation with duration phototherapy (p value <0.0001).
The increased plasma level of TAO after phototherapy is due to upregulation of antioxidant capacity.
The decrease in plasma levels of PGE2 and PGEm after phototherapy is due to the decrease of bilirubin level.
Regarding cause of jaundice:
There was no significant difference in the values of the biological markers in relation to the cause of jaundice.