What are the effects of high jaundice in children?

If a child is found to have high jaundice during examination, it will still have some impact on their future health. Therefore, once it happens, they still need to receive formal treatment as soon as possible to prevent any sequelae. Most of the time, this situation will occur in newborn babies, so appropriate treatment measures need to be taken to alleviate it.

A serious complication of neonatal jaundice is bilirubin encephalopathy. When serum bilirubin is severely elevated or high-risk factors exist at the same time, unconjugated bilirubin can pass through the blood-brain barrier into the brain, leading to bilirubin encephalopathy. It is more common within 1 week after birth, and neurological symptoms may appear as early as 1 to 2 days after birth. Hemolytic jaundice appears early, usually occurring 3 to 5 days after birth.

Premature infants or those caused by other reasons usually occur 6 to 10 days after birth. When there are high-risk factors such as premature birth, asphyxia, dyspnea or hypoxia, severe infection, hypoalbuminemia, hypoglycemia, hypothermia, acidosis or body weight less than 1.5 kg, bilirubin encephalopathy may also occur when serum bilirubin is lower than the critical value. Symptoms usually appear 12 to 48 hours after the peak of severe jaundice.

(3) Red blood cell fragility test: This test can be performed if jaundice is suspected to be caused by hemolysis but hemolytic disease due to blood type incompatibility has been ruled out. If fragility increases, consider hereditary spherocytosis, autoimmune hemolytic disease, etc. If fragility is reduced, it can be seen in hemoglobin disorders such as thalassemia.

(4) The normal methemoglobin reduction rate is >75%. This value is lower in patients with G-6PD (6-phosphate glucose dehydrogenase) deficiency, and further G-6PD activity measurement is required to confirm the diagnosis.

(5) Blood, urine, cerebrospinal fluid culture, serum specific antibodies, C-reactive protein and erythrocyte sedimentation rate examination. If jaundice is suspected to be caused by infection, blood, urine, cerebrospinal fluid culture, serum specific antibodies, C-reactive protein and erythrocyte sedimentation rate examination should be performed. The white blood cell count in the blood routine test is increased or decreased, with toxic granules and nuclear left shift.

(6) Liver function tests measure total bilirubin and conjugated bilirubin in the blood. Alanine aminotransferase is a more sensitive method to reflect liver cell damage. Alkaline phosphatase can be elevated in cases of intrahepatic bile duct obstruction or inflammation.

(7) Abdominal ultrasound is a non-invasive diagnostic technique, especially suitable for newborns. Diseases of the biliary system, such as bile duct cysts, bile duct dilatation, gallstones, biliary atresia, and gallbladder absence, can all show the pathological conditions.

(8) Electrophysiological examinations of auditory and visual functions, including brainstem auditory evoked potentials (BAEP), can be used to evaluate the functional status of auditory conduction nerve pathways, early predict brain damage caused by bilirubin toxicity, and help diagnose temporary or subclinical bilirubin neurotoxicity.