NEW TREATMENT OPTIONS IN NEONATAL HYPERBILIRUBINAEMIA

摘要

Jaundice is one of the most common problems encountered in the newborn period. It has been estimated that in the United States over 60% of the 4 million newborns born each year develop clinical jaundice with bilirubin levels greater than 5 mg/dL (86 mumol/L) in the first week of life. Bilirubin encephalopathy, known pathologically as kernicterus for the yellow staining of the subthalmic nuclei (kerns), has been recognized for a long time. The degree to which bilirubin may cause more subtle neurologic abnormalities remains controversial [1]. While clinical jaundice is commonly encountered in the newborn, kernicterus is a rare occurrence. Factors that affect bilirubin toxicity are complex and incompletely understood. These include; the serum albumin concentration and available binding sites on albumin for bilirubin, the integrity of the blood brain barrier and therefore ability for bilirubin to enter the brain, the duration of bilirubin exposure and the type and stage of development of the cells being exposed [2]. The relationship between increasing total serum bilirubin (TSB) levels, particularly greater then 20 mg/dL (344 mumol/L), and the risk of developing kernicterus in infants with Rh haemolytic disease of the newborn (HDN) was observed in the late 1940s and early 1950s [3]. This led to an aggressive approach to the treatment of jaundice in these patients with exchange transfusion being the predominant mode of therapy to maintain bilirubin levels below 20 mg/dL (344 mumol/L). In 1958 it was observed that premature infants exposed to sunlight or blue fluorescent light experienced a decrease in TSB levels [4]. This prompted the recognition of the possible use of phototherapy as adjunct therapy to exchange. The use of phototherapy as part of the management of hyperbilirubinaemia for infants has remained a standard of care for the past four decades. The use of more effective phototherapy over time has significantly decreased the need for exchange transfusions [5].