other اتیولوژی هیپربیلیروبینمی فیزیولوژیک نوزادان پژوهشی Original <div style="text-align: justify;">Etiology of Physiologic Neonatal Hyperbili&shy;rubinemia. Every newborn infant develop&middot;s hyperbilirubinemia during the first week of life which is called &quot;physiologic&quot;.&nbsp;There are several factors responsible for the development of physiologic hyperbilirubinemia, as follows:&nbsp;<br> 1. Increased bilirubin production, due to&nbsp;a - Increased blood volume.<br> b - Decreased R.B.C. survival time.&nbsp;<br> c - Increased ineffect_ive hematopoiesis.&nbsp;<br> d. Increased bilirubin production from non-hemoglobin sources.&middot;&nbsp;<br> 2 . Hepatic insufficiency in bilirubin uptake&nbsp;<br> a - Decreased Y protein in liver cells, or binding of Y protein by other anions.&nbsp;<br> 3. Hepatic insufficiency in bilirubin conjuga&shy; gation due to&nbsp;<br> a - Decreased UDP glucuronyl trans&shy;<br> ferase and UDPG dehydrogenase.&nbsp;<br> b - Inhibitory effect of maternal steroids&nbsp;<br> on the activity of glucuronyl trans&shy;ferase.&nbsp;<br> 4. Bilirubin reabsorption from intestine (en&shy;tero-hepatic circulation), due to<br> a - Absence of physiologic bacterial flora&nbsp;<br> of the intestine.&nbsp;<br> b - Presence of beta glucuronidase in&nbsp;<br> the intestine.&nbsp;<br> c - Decreased motility of the bowls.&nbsp;<br> 5. Hepatic circulation<br> a - Sudden decrease of oxygen supply to&nbsp;<br> the liver after birth.&nbsp;<br> b - Portal blood flow bypassing liver through partiaily patent ductus venosus.&nbsp;</div> 54 57 http://pejouhesh.sbmu.ac.ir/browse.php?a_code=A-10-3973-218&slc_lang=other&sid=1 Asadollah Mojtabaei اسدالله مجتبائی 100319475328460019268 100319475328460019268 Yes Faculty of Medicine, Jundishapur University, Ahvaz, Iran. دانشکده پزشکی، دانشگاه جندی شاپور، اهواز، ایران.