Gastrointestinal Infections 2 Flashcards
Clinical features of hepatitis
Preicteric: Malaise Anorexia Nausea Abdo pain Fever Icteric: Pale stool/ dark urine Jaundice
Hepatitis
Inflammatory diseases of the liver
Most commonly viral but also autoimmune disorders, drug reactions, alcohol, leptospirosis, brucellosis, liver abscesses, amoebic, pyogenic
Hepatitis A
Viral cause of hepatitis RNA Enterovirus Faecal oral transmission Contaminated food or water 2-4 weeks incubation Can be asymptomatic -> fever, malaise, anorexia, jaundice-> acute icteric hepatitis Doesn't cause chronic hepatitis Infection confers subsequent immunity Vaccination
Hepatitis B
Viral cause of hepatitis DNA virus of hepadna group 300 million carries Transmitted in blood, semen, and saliva Self limiting in most patients Rise in serum HBsAg, IgM anti-HBc Vaccinate
Five clinical patterns of hep B
Acute self limited hepatitis-> patients recover after jaundice, malaise and anorexia with immunity. 25%
Fulminant acute hepatitis-> necrosis of liver cells. Rare
Chronic hepatitis-> 5-10% May progress to cirrhosis or recover
Asymptomatic carrier state-> may later develop hepatitis
Sub clinical infection-> asymptomatic inapparent infection. 75% May become carrier or progress to chronic hepatitis.
Chronic hep B
Failure to eliminate virus from liver
HBsAg positive for more than 6 months
Either
-> chronic carrier state with no active viral replication-> anti-HBe positive-> low infectivity and low risk of inflammatory liver disease
->chronic liver disease with active viral replication-> HBeAg positive-> high infectivity and high risk of inflammatory livery disease
Hepatitis E
Clinically similar to hep A RNA virus Fecal oral spread Contaminated water Acute self limiting hepatitis-> mild infection associated with jaundice Incubation 1 month No progression to chronic Higher morality than HAV Usually associated with travel abroad
Hepatitis C
Clinically similar to hep B
RNA flavivirus
Six subtypes with different geographic incidence
Quasi species-> swam of closely related sequences within an individual
May result in false negative
Blood, semen and saliva transmission
Incubation is 2 months
Acute hepatitis with fever, malaise, anorexia and jaundice
Diagnosis of hep c
Antiviral HCV detection
HCV RNA detection -> current infection->infectious
Outcomes of hep C
Acute infection-> very rarely symptomatic
Chronic hepatitis-> 70-80%
most develop active chronic hepatitis-> many progress to cirrhosis and increased risk of hepatocellular carcinoma
Predisposing factors to chronic-> male, old, increased alcohol intake
Extra hepatic manifestations-> arthritis, agrannulocytosis
A,B,C,D,E hepatitis can cause
Asymptomatic hepatitis
Acute hepatitis without jaundice
Acute hepatitis with jaundice-> icteric
Massive necrosis of liver
B,C,D
One of the forms of chronic hepatitis
Chronic carrier state
Cholecystisis
Acute inflammation of the gall bladder
Usually secondary to gall stones
Abdo pain and tenderness, fever, vomiting
Often obstruction of cystic bile duct
Secondary infection may develop with enteric organisms-> anaerobes, coli forms
Cholongitis
Infection of the biliary tree
Usually secondary to obstruction-> inflammation
Secondary infection with gut organisms
Clinically similar to Cholecystisis but also fever, rigors, jaundice
Splenomegally
Infectious causes
-> bacterial-> TB, typhoid, brucellosis,infective endocarditis
->vival-> infectious mononucleosis
-> protozoal-> malaria, leishmaniasis, trypanosomiaisis, toxoplasmosis
Also vascular, neoplasticism, hematilogical, immunological, metabolic disorders
Rarely splenic abceses arise
