Viral Hepatitis: A C E

Clinical Terms

 Hepatitis : inflammation of liver; presence of inflammatory cells in organ tissue   Acute Viral Hepatitis : symptoms last less than 6 months Acute Hepatic Failure : Massive hepatic necrosis with impaired consciousness within 8 wks of onset of illness.

  Chronic Hepatitis : Inflammation of liver for at least 6 months Cirrhosis : Replacement of liver tissue  fibrosis, scar tissue  Fulminant Hepatitis : severe impairment of hepatic functions or severe necrosis of hepatocytes in the absence of preexisting liver disease

Pathophysiology

Targets of the Hep viruses are hepatocytes:  Hepatocyte uptake involves a receptor on the plasma membrane of the cell  After entry into the cell, viral RNA is uncoated, and host ribosomes bind to form polysomes. Viral proteins are synthesized , and the viral genome is copied by a viral RNA polymerase  Minimal cellular morphologic changes result from hepatocyte infection  Lymphocytic infiltrate ; varying degree of necrosis.

Classic presentation: infectious hepatitis

 Phase 1 - Viral replication; Patients are asymptomatic during this phase.

 Phase 2 – Prodromal  Phase 3 - Icteric phase  Phase 4 - Convalescent phase; symptoms and icterus resolve. Liver enzymes return to normal.

Clinical Evaluation: Acute Viral Hepatitis

1. Prodromal phase:

 Patients experience anorexia, nausea, vomiting, alterations in taste, arthralgias, malaise, fatigue, urticaria, and pruritus. Some develop an aversion to cigarette smoke.

 When seen by a health care provider during this phase, patients are often diagnosed as having gastroenteritis or a viral syndrome.

2. Icteric Phase

 Jaundice, Patients may note dark urine, followed by pale-colored stools.

 In addition to the predominant gastrointestinal symptoms and malaise, patients become icteric and may develop right upper quadrant pain with hepatomegaly.

Severe cases may result in Fulminant Hepatitis: 1.Hepatic Encephalopathy: B/L asterixis, palmar erythema 2.Hepatorenal syndrome 3.Bleeding diathesis

-

Clinical Evaluation: Chronic Hepatitis

Occurs after acute Hepatitis in >80% of people with HCV Some are asymptomatic , or have mild symptoms; others may only present with late complications (cirrhosis/HCC) Categorized based on grade of inflammation, stage of fibrosis, and etiology of disease

Physical Exam

 Low-grade fever.

 Significant vomiting and anorexia  dehydration such as tachycardia, dry mucous membranes, loss of skin turgor, and delayed capillary refill.

 Icteric phase: icterus of the sclerae or mucous membranes or discoloration of the tympanic membranes.

  The skin may be jaundiced and may reveal urticarial rashes .

Liver may be tender and diffusely enlarged with a firm, sharp, smooth edge.

Imaging Studies

 No specific imaging studies needed for diagnosis  Obtain the appropriate diagnostic imaging studies (eg, ultrasound, CT) if the differential diagnosis favors gallbladder disease, biliary obstruction, or liver abscess.

Liver biopsy

usually in cases of: o The diagnosis is uncertain.

o Other coinfections or disease may be present.

o The patient is immunocompromised.

o Asses severity of chronic hepatitis B or chronic hepatitis C.

Histologic Findings

Lymphocytic infiltration, moderate degrees of inflammation and necrosis, and portal or bridging fibrosis are noted. Regenerative nodules are seen in patients with cirrhosis.

Acute hepatitis: histopathology

Lymphocytes surround apoptotic hepatocytes Clustered hepatocytes with ballooning degeneration (clear vacuolated cytoplasm)

Lab Studies:

•

LFT

: Elevation of serum transaminases not diagnostic, but useful a)ALT elevated more than AST b)Acute Hepatitis: ALT > 1000 c)Chronic HCV: ALT is generally lower than 1000 * Urine analysis: presence of

bilirubin

. *

Serum bilirubin

: Total bilirubin may be elevated in infectious hepatitis. Bilirubin levels higher than 30 mg/dL indicate more severe disease.

*

Alkaline phosphatase

: if elevated significantly, consider abscess or biliary obstruction.

*

Prothrombin time

(PT) if prolonged  impaired synthetic function of the liver.

*

BUN & serum creatinine

 decreased renal function suggests fulminant hepatic disease.

*

Serum ammonia

in patients with AMS or other evidence of hepatic encephalopathy.

*

CBC:

lymphocytosis

Differentials:

Abdominal Trauma, Blunt Obstruction, Small Bowel Aneurysm, Abdominal Pancreatitis Cholangitis Pediatrics, Gastroenteritis Cholecystitis and Biliary Colic Pediatrics, Intussusception Cholelithiasis Gastritis and PUD Gastroenteritis

       

Hepatitis A

Common cause of acute hepatitis Single-stranded, positive-sense, linear RNA enterovirus (Picornaviridae) Transmission

fecal-oral route;

Contaminated water and food The incubation period of hepatitis A virus is 2-7 weeks, AST & ALT levels usually return to reference ranges over 5-20 weeks.

High risk  Travellers: vaccinations; passive immunoglobins given to those exposed Mild self-limited disease and confers lifelong immunity to hepatitis A virus. Chronic infection with hepatitis A virus does not occur.

Treatment: supportive

Diagnosis: HAV

 **Serum Serology: presence of serum antigens and immunoglobins  HAV: IgM anti-HAV: positive at the time of onset of symptoms; results remain positive for 3-6 months after the primary infection  Anti-HAV IgG appears soon after IgM and generally persists for many years.

Hepatitis C

 Spherical, enveloped, single-stranded RNA virus (Flavivirus genus)     Incubation period: 7-8 wks 170 million infected worldwide Major cause of chronic hepatitis females have better outcome in U.S. More common in Hispanic, AA population;   Parenteral Transmission: IV drug users Most common indication for liver transplantation

Hepatitis C

 Usually clinically mild, does not cause significant acute illness  Fluctuating elevations of AST & ALT  20% likelihood of developing cirrhosis  50% likelihood of developing chronic hepatitis  Incubation period: 15-150 days, with symptoms developing anywhere from 5-12 weeks after exposure.

Diagnosis: HCV

 HCV: Anti-HCV ; cannot distinguish acute from chronic infection  EIA: antibodies against core protein and nonstructural proteins; may appear 3 – 5 months after infection PCR : used to detect viral RNA  HCV 80% of cases: patients are asymptomatic and do not develop icterus.

Treatment: Interferon alpha, Ribavirin; PEG-IFNs (better sustained absorption, a slower rate of clearance, and a longer half-life than those of unmodified IFN)

Hepatitis E

 Hepatitis E virus (HEV) RNA virus of the genus Hepevirus  Enterically transmitted infection; fecal-oral route, typically self-limited  Most outbreaks occur in developing countries.

  Symptoms of acute hepatitis Incubation period of hepatitis E virus is 2-9 weeks  Case fatality rate is 4%

-

Hepatitis E: diagnosis

 Serum, liver, and stool samples can be tested for HEV RNA  Anti-HEV antibodies: IgM (acute) IgG (chronic) AST & ALT are elevated several days before the onset of symptoms; return to normal within 1-2 months after the peak severity of disease.

Treatment: supportive

A 61 yo F is brought to the ER, drowsy and disoriented, only able to follow simple commands. On PE, her abdomen is distended and non-tender and she is jaundiced. In her purse, the physician finds prescriptions for peginterferon and ribavirin. When asked to raise her hands, the physician notes a coarse tremor. Lab values show ALT = 93U/L, AST = 89U/L, total bilirubin = 3.1 mg/dL, and ammonia = 124microg/dL. What is the most likely diagnosis?

A. Bleeding esophageal varices B. Hepatic encephalopathy C. Hepatocellular carcinoma D. Hepatorenal syndrome E. Spontaneous bacterial peritonitis

Hepatitis: B & D

Robert Leahy



Hepatitis B(HBV)--

EPIDEMIOLOGY HBV is a DNA virus that belongs to the hepadnavirus family.

 2 billion people worldwide have past or present infections   400 million people are chronic HBV carriers.

Eight genotypes of HBV identified and re-labeled A through H.

 HBV is the cause of 60% to 80% of worldwide Hepatocellular Carcinoma(HCC).

 500,000 to 1 million deaths worldwide are attributed to it.

 5% to 10% of all liver transplants are attributed to HBV.

AT Risk Groups

     IV drug users People receiving multiple blood transfusions Sexual promiscuity People in contact with HBV carriers Travelers to endemic areas of South America, Southern Asia, and Africa  Resident and employees of residential care facilities  Health Care Workers

Pathophysiology

Transmission 3 main ways:  Parenterally/percutaneous route----IV Drug Users, needle sticks, Hemodialysis patients  Sexually  Vertical/ Perinatal route

Serology

HBsAg  Present in acute of chronic infection  Detectable 1 to 2 weeks after infection HBeAg  Appears shortly after HBsAg  Indicates viral Replication and Infectivity HBsAB(Anti-HBS)  Present after vaccination or clearance of HBsAg(Usually 1 to 3 months)  Indicates immunity to HBV Hb core Antibody (IgM anti-Hbc or IgG anti-HBc)  Only Serological marker of HBV during "Window Period"

Clinical Presentation

Acute Hepatitis B

- less than 6 months; Based on significant aminotransferase activity due to necro inflammatory injury  Symptoms are often non-specific symptoms such as myalgia, malaise , nausea, fatigue , pruritus, abdominal pain, RUQ, jaundice  Fulminant Hepatitis--Acute HBV results in Liver Failure

Chronic Hepatitis B

- greater than 6 months; Based on grade, stage, and etiology. Fibrosis and Necroinflammatory processes; can last for decades  Immune tolerant--High viral replication, NL liver enzymes, low inflammation and fibrosis. Seen in children or those affected early in life.

 Immune active--High Liver enzymes and High HBV DNA and HBeAg, Active Replication  Carrier State with low replication  Seroconversion from HBeAg to HBeAB   Low HBV levels, NL liver enzymes, Reduced Liver inflammation Low risk for developing of HCC

Clinical Presentation cont.

Chronic HbeAg negative  HBV DNA high, Liver enzymes high, No HbeAg  Seen in late phase of HBV Resolution  Viral clearance of HBV DNA

Diagnosis

 Serology  Liver Chemistry tests  AST, ALT, ALP, and total Bilirubin  Histology--Immunoperoxidase staining  HBV Viral DNA--Most accurate marker of viral DNA and detected by PCR  Liver Biopsy--to determine grade(Inflammation) and stage(Fibrosis) in chronic Hepatitis

Progression

 Incubation Period: 30-180 days  Acute HBV Infection: 90% resolve by themselves; less than 1% develop fulminant hepatitic failure  Chronic HBV Infection: 2-10% progress to chronic state  90% in children less than five progress to chronic state  Risk of Liver Cirrhosis: 5 year accumulation risk of 8% to 20%  5% to 10% of people progress to HCC with or without preceding cirrhosis; less than 5% achieve a chronic carrier state

Treatment

1) Interferon therapy – First Line  Method of action is the inhibition of viral replication of cells thus assisting the immune system  Interferon alpha: TX: SUB-Q 5 million units q D or 10 million units 3x weekly Sub-Q  Side effects: "Flulike Symptoms", alopecia, rash, diarrhea  pINF-alpha(pegylated interferon-alpha): 180ug q weekly SUB-Q  Better Choice than IFN-Alpha--Greater Bioavailability, Longer half life, Better treatment schedule

Treatment cont.

2) Nucleoside Analogues -- Lamivudine, Entecavir, Telbivudine Method of action is the inhibition of viral reverse transcriptase    Lamivudine  Dose : 100 mg PO q daily  Good for reducing the risk of progression to hepatic decompensation in patients with cirrhosis or advanced fibrosis  Pregnancy category B--Not teratogenic in animal studies and successful use with pregnant women   Problem: High rates of resistant mutations Side effect: lactic acidosis Entecavir – 1 st line  0.5 to 1mg PO  very effective; low resistance and greater than 90% HBV DNA clearance rate in HBeAG positive Px's.

  more effective than lamivudine Side effect: lactic acidosis Telbivudine    Dose: 600mg q daily Worse resistant profile than Entecavir Side effect: lactic acidosis

Treatment cont.

3) Nucleotide analogues  Method of action is the inhibition of viral reverse transcriptase Tenovir  Dose: 300mg qd  Highly effective with low resistance  Well tolerated  Adefovir – 1 st line  Dose: 10mg daily  Resistance less than Tenovir  Side effect: nephrotoxicity and lactic acid

Medication Guidelines

 Optimal treatment duration not yet defined  Interferon drugs don't have resistance issues unlike the antivirals

When to Treat for Chronic Hepatitis

1) HBeAg positive

HBV DNA(copies/ml)

<10 5 >10 5 >10 5 Normal Normal

ALT

Elevated (greater than 2 x ULN) Normal or elevated

Recommendation

No treatment , monitor, considered inactive No treatment, current tx is limited benefit Oral Agents, not PEG IFN Oral Agents, not PEG IFN + or - and compensated cirrhosis + or - and uncompensated cirrhosis Normal or elevated Oral agents and refer for treatment

When to Treat for Chronic

2)HBeAG negative

Hepatitis

HBV DNA(copies/ml) ALT Recommendation

<10 4 >10 4 Normal Normal >10 4 + or - w/ compensated cirrhosis + or - w/ uncompensated cirrhosis Elevated Elevated or normal Elevated or normal No tx necessary, inactive carrier Liver Biopsy , treat if abnormal Oral agents or PEG IFN Oral agents, not PEG IFN Oral agents, not PEG IFN

Prophylaxis

HBV Vaccine  Indicated for everyone and especially those in high risk groups  IM injection at 0,1,6 months in infants and adults  Response greater than 90% after 3rd dose HBV Pregnant Mothers  Give 1st dose of Hip B vaccine and Hip B Immunoglobulin(HBIG) o.5 ml within 12 hours of birth.

 2nd dose at 1 month, 3rd at 6 months     Recheck at 12 months for active infection 95% lifetime immunity Not Done---leads to 90% chronic HBV Transmitted through birth canal during birth or through umbilical cord.

Others i.e. those receiving a needle stick  Should receive 0.04 to 0.7 ml/kg of HBIG and 1st dose vaccine within 48 and no later than a week.

Transplant

 Last resort for those with advanced Liver Disease and HCC due to infection

HEPATITIS D

Transmission  Only as co-infection with acute HBV or with superinfection in chronic HBV carrier  Requires outer envelope of HBsAG for replication and transmission   Can progress to chronic disease Incubation Period 30to 150 days Serology  Hepatitis D antibody (Anti-HDV)  Indicates HDV superinfection  Ab not always present in acute infection---requires repeat testing

HEPATITIS D

Risk Factors - Same high risk groups as those for Hip B Prevention - Avoidance of Hip B and/or Hip B vaccine DX - HDV antigen in serum or finding Ab to HDV antigen Clinical  Coinfection-self limited  Superinfection-acute HBV carriers present with severe acute hepatitis infection w/ increased risk for HDV infection.

Fatality Rate - 2% to 10% Cirrhosis – None TX:IFN-alpha

Other Causes of Hepatitis

 Alcoholic Hepatitis  Drug induced Hepatitis  Autoimmune Hepatitis  Ischemic Hepatitis

A hepatitis panel is ordered for a 27 year old female as part of a routine workup for abdominal pain. Results of serological testing a negative for HBeAg and HBsAg, but positive for HBsAb and IgG HBcAb. The patient has been exposed to Hep B.

a.

Patient has recovered b.

Patient is in acute infective disease state c.

Window period d.

Chronically infected e.

Patient was never infected

Sources

1)The Washington Manual of Medical Therapeutics 2)Harrison's Principles of Internal Medicine 3)Step up to Medicine