Hepatitis of microbial origin Flashcards
Hepatitis caused by what organisms besides virus?(2)
Bacterial
Fungal
Hepatitis caused in what bacterial disease?(2)
Any systemic bacterial infection:
- Leptospirosis
- Q fever (Coxiella burnetii)
hepatitis caused by what fungal disease?(3)
Histoplasmosis
Disseminated candidiasis
Invasive aspergillosis
LEPTOSPIROSIS
Causal agent
Transmission
Route
excreted
High risk group
Leptospira interrogans
Zoonosis of rodents, cattle, pets
fecal-oral route
Leptospirae excreted in urine
Veterinarians, pet shop owners Sewage workers Farmers
- Pathogenesis of LEPTOSPIROSIS
2. Outcome /Clinical Presentation
1.Entry through mucous membranes or skin–>bacteraemia to
liver, kidneys, CNS, lungs
- Outcome /Clinical Presentation
a) PHASE 1 type 1 Anicteric leptospirosis –fever, chills, headache, myalgias- “Influenza-like illness”
b)PHASE 2: type 2Weil’s sydrome
1.aseptic meningitis
2.hepatitis
3.uraemia
4.haemorrhages
Mortality : 5%-40%
Diagnosis-investigation for LEPTO
Microbiological
- Isolation of leptospirae
- blood : first 1 - 2 weeks of illness
- urine : several weeks to months
- Culture & identification
- Microscopy
- Detection of antibodies-ELISA
- LEPTO dipstick assay
Liver Function tests
- Serum bilirubin : marked increase
- Alkaline phosphatase : marked increase
- Aminotransferases : moderate increase
Urine examination
- Microscopic changes
- Proteinuria
Blood tests * Leucocytosis : marked * Thrombocytopaenia \: mild * ESR : elevated
LEPTO Prevention
Avoid contact : Skin / Mucous membrane * Occupational hazard * Pre or Post exposure prophylaxis \: Doxycycline 200 mg per week \: Period of potential exposure * Vaccination: Human - Killed whole cell leptospiral vaccine
1.Viral Hepatitis
A,B,C,D,E,F,G?
2.What are hepatitis other than A & B called?
1. Infectious-A Serum-B, D Parentally-C Enterically-E Others- F,G
- non-A non-B (NANB
State for HEP A B C D E F G:
virus name
virus family
dna/rna
envelope
HAV : Hepatovirus : Picornaviridae : RNA : Env (-)
HBV : Orthohepadnavirus : Hepadnaviridae : DNA: Env (+)
HCV : Hepacivirus : Flaviviridae : RNA: Env (+)
HDV : Deltavirus : Deltaviridae : RNA: Env (+)
HEV : Hepevirus : Hepeviridae : RNA: Env (-)
HFV : Uncertain : :DNA:
HGV : Flaviviridae : RNA: Env (+)
A
1.Source of
virus
2.Route of
transmission
3.Chronic
infection
4.Prevention
- feces
- fecal- oral
- not chronic
- pre/post exposure/ immunization
B
1.Source of
virus
2.Route of
transmission
3.Chronic
infection
4.Prevention
- blood/ Blood derived body fluids
- Body contact
- yes
- pre/post exposure/ immunization
C
1.Source of
virus
2.Route of
transmission
3.Chronic
infection?
4.Prevention
- blood/ Blood derived body fluids
- Body contact
- yes
- blood donor Screening, risk behavior modification
D
1.Source of
virus
2.Route of
transmission
3.Chronic
infection?
4.Prevention
- blood/ Blood derived body fluids
- Body contact
- yes
4.pre/post exposure
/ immunization, risk behavior modification
E
1.Source of
virus
2.Route of
transmission
3.Chronic
infection?
4.Prevention
- feces
- fecal- oral
- no
- Drink safe water
F
1.Source of
virus
2.Route of
transmission
3.Chronic
infection?
4.Prevention
- feces
- fecal- oral
- UNKNOWN
- Drink safe water
G
1.Source of
virus
2.Route of
transmission
3.Chronic
infection?
4.Prevention
- blood/ Blood derived body fluids
- Body contact
- UNKNOWN
- risk behavior modification
Hepatitis A Virus
- Virus family
- virus shape
- presence of envelope
- DNA/RNA (SS OR DS?)
- Incubation period
6.Jaundice by
age group
- Complications
Picornaviridae
Icosahedral symmetry
Envelope (-)
ssRNA
Average 30 days
Range 15-50 days
> 14 yrs
Fulminant hepatitis (acute liver failure) Cholestatic hepatitis Relapsing hepatitis
PATHOGENESIS OF HEPATITIS A
Virus replicates in GI tract —>blood stream—>liver
Infected hepatocytes damaged by cytotoxic T cells
Infection cleared, no chronic infection, no carrier
Clinical Course of hepatitis A
symptoms of most infections
incubation period length
presence of chronic hepatitis
liver cancer presence
Most infections are asymptomatic
Fever, anorexia, nausea, vomiting and jaundice
Incubation Period : short (2 - 5 week)
No chronic hepatitis
No predisposition to liver cancer
Typical Serological Course of Hep A
SLIDE
Laboratory Diagnosis
HEP A
Acute infection is diagnosed by the detection of HAV-IgM in serum by EIA.
Past Infection i.e. immunity is determined by the detection of
HAV-IgG by EIA.
- Hepatitis A Virus Transmission
- Who are reservoirs?
- Who are commonly infected?
Close personal contact
(e.g., household contact, sex contact, child day care centers)
Contaminated food, water
(e.g., infected food handlers, raw shellfish)
Blood exposure (rare)
(e.g., injecting drug use, transfusion)
Humans are the only reservoirs
Children are more commonly infected
Specific Measures HEP A
Inactivated HAV vaccine (ACTIVE IMMUNITY)
Immune serum globulin (PASSIVE IMMUNITY)
Combined active & passive immunity
Hep B morphology
- what particles present?
- describe these particle:
- shape
infectious?
- non infectious spherical particle HBsAg
- non infectious tubular filaments of various lengths
- infectious dane particle with outer envelope and
nucleocapsid containing protein, DNA genome and DNA polymerase
Structural components of HBV
Hepatitis B Surface
Antigen
Hepatitis B Core Antigen
Hepatitis B “e “ Antigen
Viral DNA
Clinical Course HEP B
- incubation period
- symptoms of infection
- what levels are elevated/ decreased?
- spectrum of disease
1.Incubation Period : long (6 - 24 weeks)
- Many infections are asymptomatic
Fever, anorexia, nausea, vomiting, jaundice - Elevated transaminase levels
- Wide range of disease spectrum