Infectious Diseases Flashcards
which of the following is the most useful in planning the management of hep c in a patient found to have detectable HCV RNA in blood? A ALT B IFNa resistance testing C HCV RNA quantification D HCV genotype E Serum HCV IgG level
Genotype determines duration of treatment
type 1 harder to treat
A 20 yr old injecting drug user attends A&E with jaundice. He is admitted to hospital and has the following results: A Hep A total antibody positive B Hep B surface ag positive C Hep B anti-core IgM + D Hep C IgG + E Hep C RNA + Which test indicates the cause of the jaundice? A hep A total antibody B Hep B surface antigen C Hep B anti-core IgM D Hep C IgG E Hep C RNA
C
A - have acute hep A, or had hep A (IgG), or vaccinated
B - hep B infection but doesnt tell you what the virus is doing
C - IgM only comes up acutely, then goes down
D - only + after an infection
E - + the whole way through an infection
25 year old woman HBsAg + HBeAg - Hbe Ab + HB c AB + ALT 3-4x normal HB core IgM - Husband developed acute hep B 2 wks ago Next investigation? A Hep D testing B hep B DNA quantification C Hep C testing D liver USS E alpha fetoprotein
B
pre-core mutation - stop producing E antigen despite the fact that virus is replicating
B is correct as measures viral replication directly
(alpha fetoprotein is a marker for HCC)
35 yr old homosexual man 3 wk hx of fever and malaise. O/E general lymphadenopathy and splenomegaly. Unprotected sex with a number of partners. No rash or mucosal ulceration. HIV Ab test is -ve. A paul-bunnell test is weakly +. The LFTs are mildly deranged. WHich one of the following is the most likely diagnosis? A primary HIV infection B secondary syphilis C acute hep A D acute EBV E acute CMV
E
CMV has a lower prevalence (~50%) therefore more people are susceptible to having an acute infection than EBV (~90%) prevalence
Glandular fever like illness
Commonly LFTs are deranged
A is possible but hasnt had antigen test (could be a serum conversion problem) but is unlikely
25 yr old woman who is 12 wks pregnant has a 3 yr old child who develops typical chicken pox. mother doesnt recall having chicken pox. she is entirely well. What would u advise?
A avoid further contact with the child
B test the mother for varicella zoster IgG
C take acyclovir as prophylaxis
D receive varicella zoster immune globulin (ZVIG) urgently
E consider termination of pregnancy
B - 90% are immune
as 10 day window to give ZVIG so it is not urgent
which one of the following viruses is assoc with the accompanying malignancy? A HHV8 - body cavity lymphoma in HIV B HTLV1 bronchial carcinoma C HCV hairy cell leukaemia D CMV cholangiocarcinoma E HPV osteosarcoma
A
B - T cell lymphomas
C - HCC
D - no malignancy
E cervical malignancies
16 yr old boy develops severe tonsillitis prevents him from swallowing his own saliva. O/E symmetrically enlarged inflamed tonsils. Concerns airways will become compromised Management A amoxicillin and metronidazole B IV hydrocortisone C oxygen-helium mix D E
Iv hydrocortisone
alternatively gargle aspirin
20 yr olf with 4day hx of malaise, conjunctivitis and cough. Develops maculo papular rash on face and upper trunk. A parvovirus B19 B measles C rubella D E
measles
conjunctivitis is the clue - typical of measles
18 yr old - no childhood vaccinations. fevers meningism orchitis unilateral parotitis. A urine dip B blood cultures C FBC D serum IgM E CSF bacterial culture
mumps
meningism = photophobia, nuchal rigidity and headache
facial swelling and testicular swelling + rash are typical of mumps
D
outbreak of D&V. Bacterial stool cultures all negative. Likely agent?
norovirus
25 yr old gives birth to a well baby with unilateral microphthalmia. She had a rash during the 2nd trimester. Causative agent? syphilis VZV rubella CMV parvovirus B19
VZV
unilateral skin involvement
which of these are not live vaccines? Measles Mumps Rubella Diphtheria BCG hepatitis A yellow fever oral typhoid VZV meningococcal parenteral polio (salk)
Diphtheria, Hep A, meningococcal, parenteral polio (salk)
Live vaccines: measles, mumps and rubella, BCG Yellow fever oral typhoid oral polio (sabin) VZV
air steward who is HIV +. He has just started ARVs. CD4 count 180x106/l. Which of the following live vaccines is there the best evidence of a major adverse effect? yellow fever vaccine Hep B Hep A rabies Tetanus
Yellow fever vaccine as is a live vaccine
a man goes to thailand for 2 wks. 4 wks later he develops a febrile illness. diagnosis?
HIV seroconversion illness
major differential for a seroconversion illness: secondary syphilis
similar symptoms and incubations period
holiday in Spain in hotel. 4 days after develops a fever. Diagnosis
legionella
man goes to oklahoma and camps. develops febrile illness with a rash. Diagnosis
Rickettsia
Rocky Mountain spotted fever disease - tick born disease
man goes to connecticut (eastern USA) - febrile illness. Diagnosis
Lyme’s disease
Anywhere with deer (e.g. forests)
25 yr old woman - fever 40 degrees, BP 80/40. ITU - and recovers following broad spectrum antibiotics. Blood cultures -ve. 10 days later widespread desquamation staph aureus Lyme disease dengue fever measles strep pneumococcus
staph aureus
toxic shock syndome
25yr old woman malaise, fever, profuse vomiting, mild diarrhoea. erythematous rash
toxic shock syndrome
splenectomy 7yrs earlier. Presents with sepsis. BP 80/60 temp 40. Diagnosis? A staph aureus B E. coli C Capnocytophaga canimorsus D Eikenella corrodens E influenza
strep pneumo would be best answer an capsulated bacteria
capnocytophaga canimorsus
assoc with dog bites
higher risk of sepsis
35 yr old 2 wk hx of fever. echo reveals vegetation on mitral valve. Blood culture + (gram - rod). not a IVDU strep bovis pseudomonas aeruginosa treponema pallidum acinebacter sp eikenella corrodens
eikenella corrodens
acinebacter sp - doesnt cause endocarditis
trepnema - syphilis - not on blood cultures
endocarditis. Blood cultures + for strep viridans. treated with IV benzylpenicillin and gentamicin.
which requires urgent surgical intervention?
Tricuspid endocarditis causing incompetence
Increasing PR interval
Elevated CRP 24hrs after
splinter haemorrhages
rupture of aortic root abscess is a risk
Increasing PR interval on ECG
35 yr old. previously well. CAP and mild watery diarrhoea. failed to improve after 3 days amoxicillin given by GP. temp 40 degrees, headache, slightly confused. no evidence of meningitis. Peripheral WCC on upper limit normal and Na 125mmol/l. 2 other members of office are ill with similar symptoms. Mycoplasma pneumo legionella pneumo influenza A chlamydia pneumo penicillin resistant strep pneumo
Legionella- severe disease, v low sodium
2 other people in office - air conditioning spread
Not transmissible through people
whereas mycoplasma (overcrowded conditions), less severe, low sodium but not as low. unlikely to pass to people in office.
17yr old. Fever confusion hypotension (75/50) rapidly spreading purpuric rash.
obtain urgent CT scan lumbar puncture
give high dose iv steroids
administer erythromycin to penicillin allergic contacts
reverse barrier nurse for 24 hrs
take an EDTA blood sample for PCR
E - diagnostic gold standard test
meningococcal septicaemia
dont do LP - as no platelets so patient will bleed out
dont give IV steroids as dont give in absence of antibiotics
penicillin allergic contacts give rifampicin, or cipro
45 yr old. fever and meningism. CSF opening pressure 18cm, protein 0.8g/l, glucose 3.5, 560 neutrophils. Herpes simplex type 2 treponema pallidum listeria monocytogenes borrelia burgdorferi acute HIV seroconversion illness
Listeria
acute bacterial meningitis - neutrophilic
HIV & treponema & HSV - wont raise neutrophils as viruses - cause lymphocytic meningitis
78yr old alcoholic with 2month hx cough and haemoptysis, fever, night sweats and weight loss. CXR extensive bilateral apical cavitation. treated for TB. Complications acute psychosis impaired vision drug-induced hepatitis development of multi-drug resistance gout
drug induced hep
27 yr old russian - sputum strongly smear positive for AAFB> Tb diagnosed 2 yrs ago. has had a variety of short courses of treatment. You plan to admit to hosp. Management?
admit to positive pressure side room
start immediate treatment with RIPE (isoniazid, pyranzinamide, ethambutol, rifampicin)
start amoxicillin and clarithromycin
perform PCR for rifampicin-resistance gene on sputum
start immediate treatment with isoniazid, pyranzinamide, rifampicin
D - rifampicin resistance alone is v rare (so usually a hallmark of multi-drug resistant TB)
A - will blow TB around hospital
Normal TB treatment (RIPE) will not work & will cause resistant strains to thrive and induce resistance to drugs he was susceptible to
30 yr old indian woman. nodular rash, loss of eyebrows and burns on hands. ulnar nerves are thickened and tender. Skin biopsy presence and numerous AFBs. Management
Prednisolone, clofazimine, rifampicin, dapsone with close outpatient follow up
treat with prednisolone, clofazimine, rifampicin and dapsone and admit for resp isolation
treat with pred isoniazid and dapsone with close outpatients follow up
resp isolation
diagnosis is leprosy \
A - rifampicin is effective in leprosy but isoniazid is not (not D)
resp isolation is wrong as not a resp disease
40 yr old with sudden collapse. tick bite 3 month previously in a forest. bite was followed by a prolonged rash. Likely cause of collapse
meningo encephalitis
acute Bell’s palsy
stokes-adam (AV heart block)
stokes adam
