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Visual Diagnosis: A 10-week-old Infant Who Has Jaundice
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* Doernbecher Children’s Hospital, Oregon Health and Science University, Portland, OR.
 | Presentation |
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 Top Presentation Diagnosis: Extrahepatic Biliary...DiscussionDiagnosis of Biliary AtresiaSummarySuggested Reading |
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A 10-week-old female infant who presents to her primary care physician for her 2-month health supervision visit has jaundice (Fig 1
). She is the product of a term pregnancy, delivered via elective repeat cesarean section. Her birthweight was 3,300 g (50th percentile). The mother denies having any infections or taking medications during her pregnancy. The infant has appeared yellow since birth. She was breastfed for the first 2 months, then switched to formula feedings when her mother believed she had an inadequate milk supply. The infant has had no feeding difficulties; she is taking 4-oz feedings five to six times per day.
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For the past week, the infant has been colicky and fussy, but she has had no fever, vomiting, or diarrhea. Her appetite and urine output have been unchanged. There is no history of change in stool color; the stools always have been light yellow (Fig 2
). Nothing remarkable is noted on a review of systems.
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The infant lifts her head well when placed on her abdomen, follows a moving object to midline, and responds to a friendly facewith a social smile.
The patient lives with her mother and father and two siblings. All are healthy. She always has consumed treated city water, and she has not traveled recently.
There is a family history of ulcer disease, and the father had a hiatal hernia. There is no family history of blood transfusions,hepatitis, or emphysema.
Physical examination reveals an active, jaundiced female infant whose abdomen is distended. Her weight is 4.54 kg (10th percentile), length is 55 cm (5th percentile), and head circumference is 37.5 cm (5th percentile). Skin examination reveals an increased venous pattern over the abdomen (Fig 3 ); there are no rashes. Her head is normocephalic, with an open, soft anterior fontanelle. Examination of her eyes reveals yellow sclerae (Fig 4 ). Nose, throat, and neck findings are normal. Pulmonary examination reveals clear breath sounds bilaterally. There is an early II/VI systolic murmur along the left sternal border that does not radiate to the back. Abdominal examination is remarkable for an 8 cm liver span and a palpable liver edge 6 cm below the costal margin. There is no abdominal fluid wave. There is no edema in the extremities. The baby is alert, has good muscle tone, and tracks well.
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Laboratory examination at the clinic reveals the following levels: serum total bilirubin, 10.1 mg/dL (172.7 mcmol/L) with a directbilirubin of 6.3 mg/dL (107.7 mcmol/L); serum aspartate aminotransferase (AST), 121 U/L (normal, 15 to 55 U/L); alanine aminotransferase (ALT), 72 U/L (normal, 5 to 45 U/L); alkaline phosphatase, 569 U/L (normal, 145 to 420 U/L); glucose, 84 mg/dL (4.7 mmol/L); creatinine, 0.3 mg/dL (26.5 mcmol/L); and albumin, 3.1 g/dL (31 g/L) (normal, 3.9 to 5.0 g/dL [39 to 50 g/L]). A complete blood count demonstrates hemoglobin, 9.8 g/dL (98 g/L); hematocrit, 30% (0.30); white blood cell count, 16.3x 103/mcL (16.3 x 109/L); and platelet count, 684 x 103/mcL (684 x 109/L).
The patient is hospitalized for additional evaluation.
| Diagnosis: Extrahepatic Biliary Atresia Leading to Neonatal Cholestasis |
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| TopPresentationDiagnosis: Extrahepatic Biliary...DiscussionDiagnosis of Biliary AtresiaSummarySuggested Reading |
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Abdominal ultrasonography reveals hepatomegaly with normal vascular Doppler flow (Fig 5
). The gall bladder contains sludge. A sweat chloride level, serum alpha-1 antitrypsin level, and prothrombin time are normal. Serology is positive for cytomegalovirus (CMV) immunoglobulinG (IgG) and herpes simplex type-1 IgG and negative for rubella, hepatitis B, and toxoplasmosis. Results of urine testing for amino acids and urine viral culture for CMV are negative. Acardiologist’s evaluation eliminates the possibility of underlying congenital heart disease or pulmonary stenosis. Anophthalmologist’s examination is negative for posterior embryotoxon (congenital opacity of the periphery of the cornea and a marker for Alagille syndrome).
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The patient undergoes an exploratory laparotomy and intraoperative cholangiography. Liver biopsy reveals bile duct proliferationand cirrhosis compatible with extrahepatic biliary obstruction. Intraoperative cholangiography demonstrates obstruction of thecommon bile duct. The common duct is stenotic and fibrotic, confirming the diagnosis of extrahepatic biliary atresia.
After undergoing a Kasai procedure with Roux-en-Y anastomosis, the patient rapidly improves; 1 week after surgery, her totalbilirubin level is 5 mg/dL (85.5 mcmol/L).
| Discussion |
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| TopPresentationDiagnosis: Extrahepatic Biliary...DiscussionDiagnosis of Biliary AtresiaSummarySuggested Reading |
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Jaundice describes yellow staining of the skin, mucous membranes, and sclerae due to hyperbilirubinemia. Hyperbilirubinemia may be caused by increased serum levels of unconjugated bilirubin, conjugated bilirubin, or both. Jaundice in an infant older than 2 weeks of age may represent normal physiology or pathology, such as increased red blood cell hemolysis, liver disease, or biliary obstruction.
The persistence of jaundice beyond 2 weeks of age demands investigation. Physiologic hyperbilirubinemia, an unconjugated hyperbilirubinemia, appears between the second and fifth days of life and usually resolves within 10 to 14 days. Although approximately 2% of breastfed infants have a prolonged, 2- to 8-week course of unconjugated hyperbilirubinemia with bilirubin levels in the 10 to 15 mg/dL (171 to 256.5 mcmol/L) range, these infants are vigorous, eat well, and gain weight. Physical examination of infants who have human milk jaundice reveals no abnormalities other than jaundice.
Careful physical examination of the infant who has jaundice beyond 2 weeks of age may suggest the etiology of hyperbilirubinemia. Developmental delay may indicate an inborn error of metabolism. Pale skin and a cardiac flow murmur may indicate hemolytic anemia. An enlarged liver (liver span >5 cm) may suggest liver disease due to inflammation, storage disease, infiltration, intrahepatic or suprahepatic obstruction to hepatic vein outflow, or intrahepatic or extrahepatic obstruction to biliary flow. Caput medusae, or dilated tortuous veins radiating from the umbilicus, may indicate portal hypertension with obstruction of venous blood flow in the liver. Acholic or light-colored stools indicate biliary tract obstruction.
High serum unconjugated bilirubin levels may suggest increased bilirubin production (ie, increased red blood cell hemolysis),decreased delivery of unconjugated bilirubin to the liver, decreased bilirubin uptake across hepatocyte membranes, increased enterohepatic recirculation, or decreased bilirubin conjugation.
Conjugated bilirubin levels greater than 1.5 mg/dL (25.7 mcmol/L) or greater than 20% of the total bilirubin level indicate decreased bilirubin excretion due to either liver disease or biliary obstruction.
Neonatal cholestasis represents prolonged elevation of serum levels of conjugated bilirubin beyond the first 14 days of life.Neonatal cholestasis may be due to infectious, toxic, metabolic, or genetic causes or to functional impairment of bile secretion or mechanical obstruction of bile excretion. Infectious causes include viral hepatitis (CMV; hepatitis A, B, or C; rubella) toxoplasmosis, syphilis, tuberculosis, and listeriosis. Among toxic causes are sepsis, drugs, and total parenteral nutrition. Metabolic diseases include disorders of amino acid metabolism (tyrosinemia), disorders of lipid metabolism (Niemann-Pick disease, Gaucher disease), disorders of carbohydrate metabolism (galactosemia, fructosemia), and other metabolic defects, such as alpha-1 antitrypsin deficiency, hypothyroidism, cystic fibrosis, and Zellweger syndrome. Chromosomal defects include Down syndrome and trisomy E. Intrahepatic duct disease and extrahepatic duct failure lead to obstruction of bile flow. Intrahepatic duct diseases include "idiopathic" neonatal hepatitis, Alagille syndrome, intrahepatic biliary hypoplasia or paucity of intrahepatic bile ducts, and Byler disease. The two most common causes of intrahepatic cholestasis are "idiopathic" neonatal hepatitis and alpha-1 antitrypsin deficiency. Among the causes of extrahepatic duct failure/obstruction are biliary atresia, sclerosing cholangitis, bile duct stenosis, choledochal cyst, and bile/mucous plug ("inspissated bile").
Neonatal intrahepatic and extrahepatic cholestasis have similar, overlapping clinical features. Determining the type of cholestasispresent is important because early surgical correction of extrahepatic cholestasis may avoid irreversible liver damage.
Extrahepatic biliary atresia describes obstruction of the biliary tree due to congenitally absent openings of the major bile ducts.Biliary atresia results from an inflammatory process that leads to obliteration of extrahepatic ducts. Proliferation of small bile ducts is a common finding. Uncorrected biliary atresia eventually leads to periportal fibrosis and cirrhosis of the liver. Polysplenia, trisomy 18, and absence of the gall bladder also are associated with biliary atresia. On discovery of conjugatedhyperbilirubinemia, it is important to diagnose the presence or absence of biliary atresia before the infant is 2 months of age because the prognosis significantly worsens for affected infants undergoing a corrective Kasai portoenterostomy after 2 months of age. The 5-year survival rate for surgery performed before 60 days of age is 70%, between 71 and 90 days of age is 34%, and after 90 days of age is 10%.
| Diagnosis of Biliary Atresia |
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| TopPresentationDiagnosis: Extrahepatic Biliary...DiscussionDiagnosis of Biliary AtresiaSummarySuggested Reading |
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The appropriate imaging of patients in whom biliary atresia is suspected is an area of continuing debate. The gold standard for diagnosing biliary atresia has been open laparotomy withintraoperative cholangiography. Concern for possible unnecessary surgery has suggested other diagnostic methods.
The traditional initial imaging study for infants who have persistent jaundice is abdominal ultrasonography because of its easy accessibility and ability to detect a choledochal cyst and other intra-abdominal pathology. However, abdominal ultrasonography cannot demonstrate hepatitis, and the presence or absence of the gall bladder does not prove the absence or presence of biliary atresia. Ultrasonography is useful for detecting polysplenia or asplenia, conditions that are associated with biliary atresia. Published studies suggest that the presence of a triangular or tubular echodensity on hepatic ultrasonography may herald biliary atresia.
Hepatobiliary scintigraphy is used commonly to visualize the patency of extrahepatic bile ducts. Injected radioactive-labeledimidodiacetic acid analogs are selectively taken up by the liver and excreted into bile. Patients are pretreated with phenobarbitalto increase biliary excretion. The absence of tracer excreted into the small intestine within 24 hours indicates biliary atresia. The sensitivity of hepatobiliary scintigraphy is 100%, but the specificity is only 46% to 88% because patients who have a patent biliary system may not excrete detectable dye into the bowel within the 24-hour test period. Some studies suggest that the presence of a functioning gallbladder on scintigraphic examination excludes the possibility of biliary atresia, even if there is no tracer in the small intestine.
A promising new option for imaging infants in whom biliary atresia is suspected is magnetic resonance (MR) cholangiography. MR cholangiography can provide clear images of intrahepatic ducts and the common bile duct. The delineation of an incomplete extrahepatic bile duct and atrophic gall bladder on MR cholangiography suggests biliary atresia. MR cholangiography also may demonstrate periportal thickening. Unfortunately, MR images take time to collect and may be difficult to obtain in an infant.
Liver biopsy may help in the diagnosis of biliary atresia. The histologic findings of intrahepatic biliary duct proliferation in the absence of extrahepatic biliary ducts are highly indicative but not 100% specific for extrahepatic biliary atresia.
| Summary |
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| TopPresentationDiagnosis: Extrahepatic Biliary...DiscussionDiagnosis of Biliary AtresiaSummarySuggested Reading |
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The infant’s persistent jaundice, light-colored stools, hepatomegaly, increased abdominal venous pattern, and poor weight gain suggested obstructive liver disease. Although potentialcauses were many, investigation focused on determining the presence or absence of biliary atresia because early surgical correction, preferably before the infant is 2 months old, significantly reduces morbidity and mortality.
EDITOR’S NOTE.
Because we do not routinely see infants for health supervision visits between 2 weeks and 2 months of age, we may not see theinfant who has biliary atresia until it is too late for a good prognosis. We should stress to parents the importance of seekingmedical attention if newborn jaundice persists beyond the first 2 weeks of life.
| Suggested Reading |
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| TopPresentationDiagnosis: Extrahepatic Biliary...DiscussionDiagnosis of Biliary AtresiaSummarySuggested Reading |
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Dennery PA, Seidman DS, Stevenson DK. Neonatal hyperbilirubinemia. N Engl J Med. 2001;344:581-590
Gartner LM, Lee K. Jaundice in the breastfed infant. Clin Perinatol. 1999;26:431-445[Medline]
Hay SA, Soliman HE, Sherif HM, Abdelrahman AH, Kabesh AA, Hamza AF. Neonatal jaundice: the role of laparoscopy. J Pediatr Surg. 2000;35:1706-1709[Medline]
Jaw TS, Kuo YT, Liu GC, Chen SH, Wang CK. MR cholangiography in the evaluation of neonatal cholestasis. Radiol. 1999;212:249-256
Lee CH, Wang PW, Lee TT, et al. The significance of functioning gallbladder visualization on hepatobiliary scintigraphy in infants with persistent jaundice. J Nucl Med. 2000;41:1209-1213
Tan Kendrick AP, Phua KB, Subramaniam R, Goh ASW, Ooi BC, Tan CE. Making the diagnosis of biliary atresia using the triangular chord sign and gallbladder length. Pediatr Radiol. 2000;30:69-73[CrossRef][Medline]
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