Infectious Disease Flashcards
What does the hepatitis B vaccine contain
Hepatitis B surface antigen (HBsAg)
Transmission of hepatitis B
Blood
Sex
After hepatitis B vaccination what can be detected in the blood
Hepatitis B surface antibody (HBsAb)
How do you distinguish between hepatitis B vaccination and previous hepatitis B infection from serology
Hepatitis B vaccine produces HBsAb only.
Pervious hepatitis B infection produces HBsAb and HBcAg (hepatitis B core antigen)
What does hepatitis B surface antigen suggest
Active hepatitis B infection - within 4 weeks (earliest marker)
It is not detected from vaccination
What serological marker indicates chronic hepatitis B
HBsAg at 6m or more after initial infection.
Risks of chronic hepatitis
Liver cirrhosis
Liver failure
Hepatocellular carcinoma
Treatment of chronic hepatitis
Interferon-alpha
Peg interferon-alpha2a
Lamivudine
(Liver transplant)
What does hepatitis B e antigen on serology suggest
High level of infectivity
Can occur in acute or chronic hepatitis B infection.
What causes scabies
Sarcoptes scabiei - mite that burrows into the skin. F lays her eggs here. –> intense itch, worse at night
Management of scabies
Topical malathion or permethrin
Presentation of scabies
Commonly affects finger web spaces, sides of fingers, flexor surface of wrist, penis
Transmission of hepatitis A
Faecal-oral
Presentation of hepatitis A
Non-specific illness
lethargy
jaundice
Earliest serological marker of acute infection in hepatitis A
Hepatitis A immunoglobulin M Ab
Hep A IgM
What do hepatitis A IgG antibodies indicate?
Previous hepatitis A infection
Usually conveys immunity to hepatitis A
How is hepatitis C transmitted
Sex
Blood
Presentation of hepatitis C infection
Acute infection normally silent - asymptomatic
Chronic infection occurs in 85% –> risk of cirrhosis, liver failure, hepatocellular carcinoma
Symptoms of glandular fever
Sore throat Swollen lymph nodes Flu-like symptoms Malaise Swelling around eyes Splenomegally
Where does campylobacter jejuni come from and what are the symptoms
Contaminated food
Unpasteurised milk
Profuse bloody diarrhoea, containing pus
What type of meningitis affects patient with HIV
Cryptococcus neoformans
Features of HIV seroconversion
Flu-like illness
At what CD4 count can AIDS defining illness occur
CD4 count <200
At what CD4 count is antiretroviral therapy started
CD4 count of 350
In HIV treatment what viral load is the aim of treatment
Viral load <50 copies /ml
In what infection do ‘owls eye’ bodies occur
Cytomegalovirus (CMV)
What organism causes kaposi’s sarcoma
Human herpes 8
Examples of viral haemorrhagic fevers
Ebola
Lassa fever
Marburg
Yellow fever
Symptoms of pertussis
Coryza Mild fever Cough - becomes violent whooping Vomiting Respiratory distress
Symptoms of tetanus
Rigid jaw muscles
Dysphagia
Neck/back / chest / abdominal muscle spasm
What infection causes a rash with ampicillin
EBV
Conditions caused by EBV
Glandular fever
Burkitts lymphoma
Nasopharyngeal carcinoma
Hodgkin’s lymphoma
Cause of slapped cheek rash
Parvovirus B19
5th disease
Symptoms of herpes simplex 1
Cold sores
Gingivostomatitis
Herpetic whitlow
Eczema herpeticum
Where does leishmaniasis come from
Sand fly Protozoa
What causes listeriosis and what are the symptoms
Contaminated soft cheese / pâté
Fever / myalgia / diarrhoea
Miscarriage / stillbirth if pregnant
Where does leptospirosis come from?
Rat or cow urine in water
Watersports
Farm work
Symptoms of mumps
Parotid gland swelling Headache Arthralgia Nausea Fever Dry mouth Fatigue Orchitis (20%)
Symptoms of rubella
Mild illness Fine red maculopapular rash Fever Sore throat Conjunctivitis Lymphadenopathy
Symptoms of measles
Fever
Cough
Rash ( head / neck 1st)
Koplicks spots on Buccal mucosa
Common wound infections
Staph aureus
Staph epidermidis
E. coli
Enterococci
Infections common in asplenic patients
Strep pneumonia
N. meningitidis
H. Influenzae
Malaria
Examples of oncoviruses
EBV
Hep B
HTLV-1
HPV16+18
Causes of bloody diarrhoea
Enterohaemorrhagic E. coli Campylobacter jejuni/ coli, Shigella spp Clostridium difficile NOT viral or parasitic - except Entamoeba histolytica
What complications can leptospirosis cause
Meningism Renal failure Hepatomegally Jaundice Haemolytic anaemia Cardiac failure Arrhythmia
Complications of parvovirus
Erythema infectiosum
Arthropathy
Aplastic crisis in patients with chronic haemolytic anaemia
Chronic infection in the immunocompromised
Asymptomatic infection
What viral infections can cause arthropathy
Mumps Rubella Parvovirus B19 Hepatitis A, B,C HIV EBV
Organism responsible for cat scratch disease
Bartonella henslae
Organism responsible for Lyme disease
Borrellia burgdorferi
In whom does pseudomonas commonly occur
Neutropenic / immunosuppressed patients
E.g. Leukaemia / CF / diabetes / burns victims
Examples of alpha streptococci
Strep pneumoniae
Strep viridans
