Cholestatic liver diseases of Infancy – a liver biopsy pattern-based approach Basel Seminars in Pathology Paediatric Pathology and Genetics Pierre Russo, MD Director, Division of Anatomic Pathology The Children’s Hospital of Philadelphia Professor, Department of Pathology and Laboratory Medicine Perelman School of Medicine at the University of Pennsylvania Objectives • To define neonatal cholestasis and neonatal hepatitis • To outline the evaluation of neonatal cholestasis • To review the potentially fatal / treatable etiologies of neonatal cholestasis where the correlation between clinical features and histopathology is critical • To illustrate various histologic patterns in liver biopsies from cholestatic infants and their differential diagnosis Pediatric Liver Disease • Children are not little adults • However, many adult liver diseases are also seen in pediatric patients – Hepatitis B – Hepatitis C – Autoimmune hepatitis • Unique to pediatric hepatology – Neonatal cholestasis – Emphasis on metabolic and genetic disorders Definitions • Cholestasis – impairment of bile formation or reduction of bile flow from the liver. – Bile acids – Bilirubin – Cholesterol – Organic anions, drugs and toxins • Hepatitis - inflammation of the liver • Jaundice – discoloration of skin, sclera or mucous membranes resulting from elevated unconjugated or conjugated bilirubin • Conjugated hyperbilirubinemia > 2.0 mg/dl or >15% of total bilirubin 15% Of Neonates Develop Jaundice Physiologic vs pathologic jaundice • Physiologic jaundice – essentially means unconjugated hyperbilirubinemia - common and nearly never dangerous • Neonatal cholestasis is always pathologic, and essentially means conjugated hyperbilirubinemia (with a few exceptions) • Neonatal cholestasis - an emergency with potential for fatal outcome and chronic disease. It is never normal. • Any infant with jaundice after 2 weeks of age should have a fractionated bilirubin to assess for conjugated hyperbilirubinemia Differential Diagnosis Of Neonatal Cholestasis Neonatal Hepatitis Cholestatic syndromes • Peroxisomal disorders • Idiopathic NH • PFIC – Zellweger • Viral NH – Type 1 Byler P-type ATPase – Infantile Refsum – CMV – Type 2 Canalicular Bile Acid Tx – Other enzymopathies – Herpes – Type 3 MDR3 deficiency • Bile acid synthetic disorders – Rubella • Aagenaes cholestasis lymphedema – 3b-hydroxysteroid dehydrogenase/i – Reovirus – Adenovirus • N. Am. Indian Cholestasis – D4-3-oxosteroid 5b-reductase – Enteroviruses • Nielsen Greenland Eskimo cholestasis – Oxosterol 7a-hydroxylase – Parvovirus B19 • Benign Recurrent Intrahepatic cholestasis Toxic – Paramyxovirus • Dubin Johnson MRP2 cMOAT deficiency • Drugs – Hepatitis B • Rotor syndrome • Parenteral alimentation – HIV Metabolic disorders • Aluminum • Bacterial and parasitic • a1-antitrypsin deficiency Miscellaneous associations – bacterial sepsis • Cystic fibrosis • Shock/hypoperfusion – UTI • Neonatal iron storage disease • Histiocytosis X – Syphilis • Endocrinopathies • Neonatal lupus erythematosus – Listeriosis – Hypopituitarism • Indian childhood cirrhosis – Toxoplasmosis – Tuberculosis – Hypothyroidism • Autosomal trisomies 17, 18, 21 – Malaria • Amino acid disorders • Graft v host disease Bile duct obstruction – Tyrosinemia • Erythrophagocytic lymphohistiocytosis • Cholangiopathies – Hypermethionemia • ECMO – Biliary atresia – Mevalonate kinase deficiency • Veno-occlusive disease – Choledochal cysts • Lipid disorders • Donahue leprechaunism – Nonsyndromic Paucity – Niemann-Pick A, B • Arthrogryposis cholestasis – Alagille syndrome – Niemann-Pick C • Erythroblastosis fetalis – Sclerosing Cholangitis – Gaucher – Spontaneous duct perforation – Wolman – Caroli disease – Cholesterol ester storage ds – Congenital hepatic fibrosis – Bile duct stenosis • Urea cycle disorders • Other – Arginase deficiency – Inspissated bile/mucus • Carbohydrate disorders – Cholelithiasis – Galactosemia – Tumors – Fructosemia – Masses – Glycogen storage IV • Mitochondrial disorders – Oxidative phosphorylation Classification of Neonatal Cholestasis Extrahepatic Intrahepatic Biliary atresia Neonatal hepatitis Choledochal cyst Alagille syndrome Bile duct stenosis Galactosemia Stones CMV Tumors TPN Α1- antitrypsin deficiency There is overlap in clinical presentation, laboratory abnormalities, and histology. Guiding Principles for Evaluation of the cholestatic infant • There are over 100 etiologies • Many complex, rare metabolic diseases which have new and effective therapies • Design initial evaluation according to: – What is dangerous and treatable? – What is common? – What patterns provide clues for specific etiologies? Etiologies Of Neonatal Conjugated Hyperbilirubinemia n= %age Biliary atresia 377 34.7% Idiopathic neon. hepatitis 331 30.5% a1-antitrypsin deficiency 189 17.4% Other hepatitis 94 8.7% Alagille syndrome 61 5.6% Choledochal cyst 34 3.1% Mieli-Vergani G, et al. Lancet 1989. King’s College Hospital Important Critical Etiologies: Early Treatment Improves Outcome • Biliary atresia Kasai portoenterostomy • Extrahepatic obstruction Surgery • Galactosemia Lactose restriction • Tyrosinemia NTBC • Hypopituitarism Cortisol, thyroxine • Bile acid synthetic defects Cholic acid • Sepsis and urinary tract infection Antibiotics • Syphilis Antibiotics Russo P, Rand EB, Loomes KM. Chapter 10 Diseases of the Biliary Tree in Pathology of Pediatric Gastrointestinal and Liver Disease, Springer, 2014 Percutaneous Liver Biopsy A useful, commonly essential, and many times mandatory step in the evaluation of neonatal and infantile liver disease prior to OR cholangiogram. Collaboration – communication Amount of tissue needed Special studies or assays PCR or cultures Special stains Electron microscopy The Clues to Diagnosis Jaundice Physiologic --- Pathologic Bilirubin Unconjugated --- Conjugated Site Intrahepatic --- Extrahepatic Type Metabolic --- Anatomic Histology Hepatitis,Paucity--- Proliferation GGT Low --- High Systemic Abnormalities --- Isolated Synthesis Normal --- Abnormal The liver biopsy – major histologic patterns in neonatal cholestatic disorders • Obstructive pattern • Giant cell Hepatitis • Intrahepatic bile duct paucity Liver biopsy “obstructive pattern” 2 month-old Biliary Atresia Biliary Atresia • Most severe chronic liver disease of infancy • Fibro-inflammatory obliteration of the biliary tree • Etiology unknown (viral, autoimmune, toxic) • 1/8,000 live births in US (400 cases/yr); higher in Asia • Untreated, death from cirrhosis < 1 year of age • Most common cause of pediatric liver transplantation worldwide Diagnosis Of Biliary Atresia Typical scenario Well appearing child Days to weeks old Acholic stools, dark urine Mild icterus Hepatosplenomegaly Conjugated bilirubin Mildly elevated ALT Elevated GGT Operative and Endoscopic Cholangiography Operative cholangiogram Gold standard Difficult in Alagille syndrome Endoscopic retrograde cholangiogram Not widely available Technically difficult Expensive Rarely therapeutic Risks unknown What does it add? Kasai Hepatoportoenterostomy Morio Kasai Biliary Atresia – the remnant Biliary Atresia – remnant histology Hepatic ducts Normal, 40 weeks BA, 2 months Biliary Atresia – the explant 80% - 85% of children will require liver transplantation 40% have failure of HPE without achieving good biliary drainage, requiring liver transplantation < 2 yrs Bile duct loss Differential Diagnosis of Obstructive Cholestasis on Liver Biopsy Alpha-1 antitrypsin deficiency low or absent serum alpha-1 antitrypsin level, PiZZ phenotype Choledochal cyst Ultrasonographic and cholangiographic findings Alagille syndrome (early) Associated malformations, mutation in JAG1 or Notch2 gene Cystic fibrosis History of meconium ileus, failure to thrive, positive sweat test TPN hepatopathy History of prematurity and TPN use Neonatal sclerosing cholangitis Ichthyosis, scarring alopecia, dysmorphism, Claudin-1 mutations Progressive familial cholestasis Usually older infants at presentation; absence type 3, ABCB4 disease of immunohistochemical staining for MDR3 along canaliculi Galactosemia Extensive fatty change Tumor, stone or other mechanical obstruction a1 ANTITRYPSIN DEFICIENCY Emphysema Neonatal hepatitis Cirrhosis Disease due to mutations of protease inhibitor (Pi) gene (chr 14) a1-Antitrypsin Deficiency 7 week-old with a1-AT deficiency α1 Antitrypsin Deficiency Choledochal cyst •1/15,000 livebirths (1/1000 in Japan) •4:1 F:M •50% dx’d < 10yrs of age; 25% < 20 yrs of age •10% lifetime risk of carcinoma Obstructive cholestasis - Parenteral Nutrition 3 months Parenteral Nutrition • 2 month-old ex 32 week premie with jejunal atresia s/p resection and reanastomosis, on TPN majority of his life • Now off TPN but still cholestatic, please evaluate for BA Obstructive pattern- cystic fibrosis 2 month-old boy with cholestasis Obstructive pattern - Galactosemia • Autosomal Recessive • FTT, vomiting, diarrhea • E. coli septicemia • Hemolytic anemia • Progression to cirrhosis in 6 months if untreated • Treatment is dietary removal of lactose • Neonatal screening Obstructive pattern with fat in liver available Neonatal sclerosing cholangitis • Neonatal ichthyosis- sclerosing cholangitis syndrome (NISCH) • Scalp hypotrichosis • Scarring alopecia • Leukocyte vacuolization • Claudin-1 gene, 3q27 Claudin-1 staining, Grosse, Hepatol 2012 5 months Obstructive pattern - Langerhans cell histiocytosis 8 month-old girl with cholestasis and skin rash CD1a LCH - Liver explant CD1a The liver biopsy – major histologic patterns in neonatal cholestatic disorders