80 -- 90% Most common cause of UGIB in Children Etiology Causes of extraheptatic poal vein obstruction Idiopathic Poosplenic vein inflammation or injury - Umbilical sepsis - Umbilical catheterization - Neonatal peritonitis - Abdominal trauma - latrogenic operative trauma to the poal vein Indirect causes Neonatal systemic sepsis from nonintra- abdominal sources - Dehydration - Multiple exchange transfusions Hypercoagulable states. Drugs Pregnancy Congenital abnormalities - Poal vein stenosis - Poal vein atresia or agenesis. Pathology On gross examination, the original poal vein is difficult to identify as it is replaced by a cluster of variable -- sized vessels, arranged haphazardly within a connective tissue suppo. "Cavernous' malformation of protalvein" On histological examination, - The architectural pattern of the liver is preserved - Liver biopsy is necessary in a patient with ElIPV0 if the liver functions are deranged. - Role of liver biopsy is limited but is used to exclude other liver disease. Hemodynamics of EHPVO Hepatic vein pressure gradient is normal in EHPVO Intravariceal and intrasplenic pressures closely reflect poal pressure - These are elevated in EHPVO patients and suggest poal hypeension Diagnosis of EllPV0 Imaging -EHPVO is diagnosed by imaging techniques such as Doppler US, CT or magnetic resonance imaging (MRI). which demonstrate poal vein obstruction, presence of intraluntinal thrombus in the poal vein and / or "poal vein cavernoma" Liver Biopsy -The role of liver biopsy in the diagnosis of EHPVO is limited, as mentioned above Non cirrhotic poal fibrosis (NCPF) It is a disease of unceain etiology characterized by poal .ftbrosis and involvement of small and medium brunches of poal veins -poal hypeension. The liver functions and structure primarily remain normal. Epidemiology of NCPF It is universally present but more common in developing countries than developed countries More prevalent in low socio-economic groups The peak age of incidence is 3rd-4th decade Etio- pathogenesis A number of hypotheses have been proposed Infections: - Septic poal circulation throhi may have a role to play as thrombin may activate stellate cells Xenobiotics exposure: Prolonged exposure may lead to NCPF. - Inorganic Arsenic exposure may play a role, however. the mechanism is poorly understood. Immunologic abnormalities : In comparison to controls - The total peripheral T lymphocytes (TI) and suppressor/ cytotoxic (T8) lymphocytes are decreased - The ratio of T4 to T8 lymphocytes is high. - The Vascular cell adhesion molecule 1 and TNF- receptor I & 11 are high in IPH. - TNF is involved in the induction and maintenance of fibrosis Clinical Presentation of NCPF Patients present with well tolerated episodes of GI hemorrhageQ Mass in left hypochondrium, splenomegalyQ AscitesQ and jaundicee may transiently develop during GI bleeding episode Natural history of NCPF There may slowly developing liver atrophy but liver functions are maintained GI bleeding is still the major cause of death. The life expectancy is longer than cirrhotics but lower than healthy controls Up to 100% 5 Years survival is expected provided varices are eradicated. Hemodynamics in NCPF WHVP is usually normal or mildly increased Poal pressures are elevated significantly Infra - variceal pressure is high and reflects poal pressures in NCPF Diagnosis of NCPF Poal hypeension related GI bleeding Splenomegaly without chronic liver disease Growth retardation No evidence of decompensated chronic liver disease Absence of viral/ other etiology of chronic liver diseases Prevalence of Varices and Variceal bleeding risk Esophago-gastric varices are present in 85- 95% cases Gastric varices are common in NCPF than in cirrhosis (up to 44% of cases) 70% of patients present with variceal bleeding NCPF may constitute up to 15% of poal hypeension related bleed. NCPF Vs EHPVO NCPF and EHPVO are similar in all aspects except the .following two points :? NCPF EHPVO Most common in young adults * Most common in children Patent spleno poal axis * Extrahepatic obstructtion of poal veins (Cavernous malfonnation of poal vein)">