Gastrointestinal and Liver Disease Final PDF

GASTROINTESTINAL AND HEPATOBILIARY DISORDERS Professor Abdellatif Abdelmoez Professor of Pediatrics, Faculty of Medicine Asyut University  Abdominal wall defects Umbilical hernia Omphalocele Gastroschisis Umbilical hernia Umbilical Hernia ▪ Failure of th...

GASTROINTESTINAL AND HEPATOBILIARY DISORDERS Professor Abdellatif Abdelmoez Professor of Pediatrics, Faculty of Medicine Asyut University  Abdominal wall defects Umbilical hernia Omphalocele Gastroschisis Umbilical hernia Umbilical Hernia ▪ Failure of the umbilical ring closure, weakness of abdominal muscles ▪ Most are small and resolve in 1-2 years without any treatment ▪ Surgery if: getting larger after 1-2 years, symptoms (strangulation, incarceration), and/or persistent after age 4 Omphalocele ▪ Failure of intestines to return to abdominal cavity with gut through umbilicus ▪ Covered in a sac (protection) ▪ Associated with other major malformations and possible genetic disorders (trisomy) ▪ Large defects need a staged reduction (use of a surgical Silo), otherwise respiratory failure and ischemia Gastroschisis ▪ Defect in abdominal wall lateral to umbilicus ▪ Any part of the GI tract may protrude ▪ Not covered by a sac ▪ Major problem with the intestine: atresia, stenosis, ischemia, short gut ▪ Surgery based on condition of gut; if no ischemia, large lesions need a staged reduction as with omphalocele Gastroschisis VS Omphalocele Necrotizing enterocolitis (NEC) Pneumatosis intestinalis ▪ Transmural intestinal necrosis ▪ Greatest risk factor is prematurity; rare in term infants ▪ Symptoms usually related to introduction of feeds: bloody stools, apnea, lethargy, and abdominal distention once perforation occurred ▪ Pneumatosis intestinalis on plain abdominal film is pathognomonic (air in bowel wall) Treatment ▪ Cessation of feeds, gut decompression, systemic antibiotics, and supportive care ▪ Surgical resection of necrotic bowel may be necessary IMPERFORATE ANUS Failure to pass stool after birth No anal opening visible Treatment is surgical correction. May be part of VACTERL association. Neonatal jaundice  Defenition Neonatal jaundice is the yellowish discoloration of the eyes, skin and mucous membrane in the first month of life due to elevated level of bilirubin in the blood  A 2-day-old infant is noticed to be jaundiced. He is nursing and stooling well. Indirect bilirubin is 11.2 mg/dL; direct is 0.4 mg/dL. Physical exam is unremarkable except for visible jaundice  Pathophysiology Increased production of bilirubin from breakdown of fetal red blood cells plus immaturity of hepatic conjugation of bilirubin and elimination in first week of life Rapidly increasing unconjugated (indirect reacting) bilirubin can cross the blood brain barrier and lead to kernicterus (unconjugated bilirubin in the basal ganglia and brain stem nuclei). Hypotonia (later hypertonia and rigidity), seizures, opisthotonos, delayed motor skills, choreoathetosis, and sensorineural hearing loss are features of kernicterus.  Kernicterus (Bilirubin Encephalopathy) Kernicterus is an important complication of indirect hyperbilirubinemia) Physiologic Jaundice Versus Pathologic Jaundice  NOTE Work up for pathologic hyperbilirubinemia when: -It appears on day 1 of life -Bilirubin rises >5 mg/dL/day -Bilirubin >13 mg/dL in term infant -Direct bilirubin >2 mg/dL at any time The causes of hyperbilirubinemia with respect to bilirubin metabolism are as follows: ❑RBC metabolism Increased number of RBCs Physiologic jaundice (healthy newborn [normal Hct (42−65]) Polycythemia (Hct >65) 1- Increased RBC production: Chronic hypoxia, IUGR, post-mature; IODM, Beckwith-Wiedemann syndrome (insulin effect); maternal Graves disease (transplacental antibodies); trisomies (unknowm mechanism). 2-Extra RBCs entering the circulation: delayed cord clamping, twin-twin transfusion 3-Treatment: partial exchange transfusion with normal saline (dilutional) Increased hemolysis Immune-mediated (labs: high unconjugated bilirubin, may be anemia,increased reticulocyte count, positive direct Coombs test) i. Rh negative mother/Rh positive baby: classic hemolytic disease of the newborn (erythroblastosis fetalis) ii. ABO incompatibility (almost all are type O mother and either type A or B baby): most common reason for hemolysis in the newborn iii. Minor blood group incompatibility (Kell is very antigenic; Kell negative mother), uncommon Non-immune mediated: same as above but Coombs is negative; need to see blood smear i. Smear shows characteristic-looking RBCs: membrane defect (most are either spherocytosis or elliptocytosis ii. Smear shows normal-looking RBCs: enzyme defect (most are G6PD deficiency then pyruvate kinase deficiency) iii. Extravascular: excessive bruising cephalohematoma ❑ Bilirubin is then bound to albumin and carried in the blood; bilirubin may be uncoupled from albumin in the blood stream to yield free bilirubin, e.g. neonatal sepsis, certain drugs (ceftriaxone), hypoxia, acidosis. ❑ Bilirubin is transported to the hepatocytes: within the hepatocytes is the conversion of unconjugated (laboratory indirect-acting) fat- soluble bilirubin to conjugated (glucuronide) water-soluble bilirubin (laboratory direct-acting) by the action of hepatic glucuronyl transferase (GT). -Decreased enzymatic activity of GT o Normal newborn first week of life o Primary liver disease of systemic disease affecting the liver (sepsis,TORCH, metabolic diseases o No GT activity: Crigler-Najjar syndrome (type I) ❑ Transport through the intrahepatic biliary system to the porta hepatis for excretion into the duodenum; abnormalities of transport and excretion cause a conjugated (direct) hyperbilirubinemia (>2 mg/dL direct-acting bilirubin in the blood in the newborn). - Biliary atresia (progressive obliterative cholangiopathy): obstruction at birth due to fibrosis and atresia of the extrahepatic ducts (and so no gall bladder); then variable severity and speed of inflammation and fibrosis of the intrahepatic system which ultimately leads to cirrhosis o Most present in first 2 weeks of life with jaundice (conjugated hyperbilirubinemia), poor feeding, vomiting, lethargy, hepatosplenomegaly, persistent acholic stools and dark urine Normal biliary system Biliary atresia Persistent Persistent Acholic stool Dark urine Baby with biliary atresia After liver transplant o Best initial test: U/S (triangular fibrotic cord at porta hepatis; no evidence of normal ductal anatomy; no gallbladder o Most accurate test (next step): percutaneous liver biopsy (is pathognomonic for this process) o Best initial treatment (palliative): hepatic portojejunostomy (Kasai procedure) o Best long-term management: liver transplant - Liver disease (primary or secondary to systemic disease): cholestasis (sepsis, perinatal infections, metabolic disease, neonatal hepatitis, severe hypothyroidism and others ❑ Intestinal transport and excretion Most bilirubin is eliminated in the stool with final products synthesized with help of colonic bacteria; some bilirubin is eliminated in the urine, some is reprocessed in the liver due to enterohepatic circulation (along with bile acids); Intestinal beta glucuronidase hydrolyzes glucuronide-bilirubin bonds to yield some unconjugated bilirubin, which is absorbed into the portal circulation and transported back to the liver to be acted upon by hepatic glucuronyl transferase -Increased enterohepatic circulation o Intestinal obstruction o Decreased colonic bacteria (first week of life, prolonged antibiotics, severe diarrhea) Breast-feeding and breast milk jaundice Hemolytic Disease of the Newborn It is an isoimmunity hemolysis associated with: Rh incomoatibility or ABO incompatibility Hemolytic Disease of the Newborn due to Rh incompatibility  Can occur in first born baby Etiology and workup of neonatal hyperbilirubinemia Jaundice workup Treatment of indirect hyperbilirubinemia Phototherapy Phototherapy is the primary treatment in neonates with unconjugated hyperbilirubinemia Complications: ▪ loose stools, ▪ erythematous macular rash ▪ overheating leading to dehydration, ▪ bronze baby syndrome (occurs with direct hyperbilirubinemia; dark, grayish-brown discoloration of the skin [photo-induced change in porphyrins, which are present in cholestatic jaundice]) Double volume exchange transfusion If bilirubin continues to rise despite intensive phototherapy and/or kernicterus is a concern Phototherapy Intensive phototherapy Baby treated with phototherapy can develop fever, dehydration, skin rash, skin color change (bronze baby), some loose stools. These babies should be monitored specially for fluid loss and fever. Double Volume Exchange transfusion Donor blood Waste blood  Take home message Neonatal jaundice is one of the most common conditions occurring in newborn infants. The most common cause of neonatal jaundice is a physiological rise in unconjugated bilirubin. Pathological neonatal jaundice can be conjugated or unconjugated and is typically a symptom of an underlying disease.  The degree of hyperbilirubinemia can be measured by transcutaneous and/or serum bilirubin measurements. Treatment modalities include phototherapy, exchange transfusion, in addition to specific Therapies for underlying conditions Treatment is targeted at reducing the risk of kernicterus and hence permanent neurological sequelae. A newly born full term male baby was found to have an uncovered intestinal loops protruded through an abdominal defect in the right paraumbilical area. Which of the following is the most possible diagnosis? a) Diaphragmatic hernia b) Ompalocele c) Umbilical hernia d) Gastroschisis e) Paraumbilical hernia A 7-day-old preterm baby 31 weeks of gestation was given IV nutrition during the first week of life then started on enteral feeding, the baby noticed to be lethargic, with attacks of apnea, and bloody stool. Two days later abdominal distension was observed with more deterioration of general condition. Which of the following carries the greatest risk factor for development of this condition? a) Introduction of enteral feeding b) The postnatal age of baby at which he is catching this disease c) Presence of bloody stool d) Initial feeding with IV nutrition e) Prematurity A 3-day-old breast-fed infant presents with yellowish skin. Both the mother and the baby have O +ve blood. The baby's total serum bilirubin is 11.8 mg/dl and direct serum bilirubin is 0.2 mg/dl. The Hb is 17 gm/dl. Platelets 278,000/ul. Reticulocyte count is 1.5%. The peripheral smear does not show abnormalities. Which of the following is the most likely diagnosis? a) Breast feeding jaundice b) Rh or ABO incompatibility c) Physiologic jaundice d) Sepsis e) Congenital spherocytic anemia A primiparous woman whose blood type is O positive gives birth at term to a baby girl who has A positive blood. A serum bilirubin level obtained at 18 h of age is 10 mg/dL and Reticulocytes 8%. Which of the following laboratory tests will be your next step? a. Measuring direct bilirubin level b. Direct Coombs test c. Blood smear d. CBC with differential count e. Measuring G6PD level