Past Paper corrections Microbiology Flashcards
community acquired pneumonia management?
based on curb-65 score
0-1 = amoxicillin
2 = amoxiciliin + clarithromycin
2-3 = admit and give IV (C)o-amoxiclav and IV (C)larithromyin
Typhoid fever treatment
IV ceftriaxone + PO azithromycin
teenager with meningitis. glucose is normal, protein in normal and white cells are raised (mononuclear cells).
most likely causative organism?
this is aseptic meningitis
viruses are cause
and enteroviruses!! = most common = cocksackie!!!!, echovirus
(other viruses - mumps, hsv2)
A medical student undergoes blood-borne virus screening before starting clinical placements. They test positive for HBsAg and Anti-HBc; negative for IgM anti-HBc and anti-HBs.
What is their HBV infection status?
what does each marker indicate if positive?
chronic infection
positive HbsAg (surface antigen) = Hep B infection!! (outside is touching u*)
positive anti HBs = Antibody tos HbsAg = immunity to HepB either due to prior vaccination or prior infection
positive anti HBc = If IgM then acute infection(, if IgG = chronic infection or prior exposure -> answer depends on presence of HbsAg
*essentially, look at HbsAg first to guide answers
(HbeAg presence = high transmissibility)
During pregnancy, pregnant women are offered vaccines. One of these is Covid vaccine. State one of the other 2
influenza, whooping cough
What 3 infections are checked in pregnant women according to UK screening program?
hep B, HIV, syphilis?
Which fungus that can cause respiratory disease in immunocompromised cannot be treated using a certain type of antifungal (cos it doesn’t have ergosterol in its cell wall), it’s normally treated with co-trimoxazole?
pneumocystis jirovecii
Man with cavitating pneumonia and blood speckled phlegm, dx organism
hemophilus influenzae
A man with HIV, CD4 count under 50, non-compliant with HAART develops diarrhoea and abdo Sxs. Acid and alcohol fast bacilli. Which atypical mycobacterium caused this?
ulcerans
-> note crytptospordium causes diarrhea too but this is a parasite
Hepatitis antigen & Abs bloods. What would the serology show in someone who has previously recovered but is at risk of reinfection if they become immunocompromised?
Hep surface Ag -ve, core Ab +ve, surface Ab -ve?? -> double check
note - negative surface antibody so it means they have no immunity!!
Lady with bronchiectasis known to be colonised with fully sensitive Pseudomonas aeruginosa, what antimicrobial should be used?
ceftazidime
A 19 yo boy has meningococcal Meningitis. Dad Says he is deathly allergic to penicillins and cephalosporins due to anaphylactic reactions. Which antibiotic should you use instead?
chloramphenicol
Elderly gentleman presents with pneumonia symptoms, coughing up yellow sputum. Culture shows gram-ve coccobacilli.
Haemophilus,
What species of Coagulase Negative Staphylococcus is a common cause of lower urinary tract infection in young women?
staphylococcys saprophyticus, it is urease test positive, as is proteus and klebsiella
A 67-year-old woman presents with a chronic cough, haemoptysis and fevers particularly at night. She states she has lost 10 kg of weight over the past 3 months and her chest X-ray shows left upper zone shadowing. Her son reports she has a history of excess alcohol consumption. What is the most likely causative organism?
klebsiella pneumoniae?? - double check
What double stranded DNA virus is associated with nephritis in renal transplant recipients on immunosuppresive therapy?
CMV
A 72 year old woman is referred from the Emergency Department with signs and symptoms consistent with meningitis. She is known to have hypertension and type 2 diabetes mellitus. She is not confused and has no features. suggestive of encephalitis. A lumbar puncture has been performed and she has been commenced her on ceftriaxone 2g IV twice daily. There are no known drug allergies. Given this clinical picture, what one anti-microbial should be given in addition?
amoxicillin (due to RF for listeria ie young or old)
Serology for what polysaccharide is used for the diagnosis of invasive Aspergillus infection? -
galactomannan
A 32 year old woman has been diagnosed with a superficial infection of a caesarean section wound. The preliminary report from a wound swab states: Staphylococcus Aureus isolated with susceptibilities to follow. The pre-operative MRSA screen was negative and there are no known any drug allergies: She is breast feeding her new daughter. What narrow Spectrum antimicrobial would you prescribe to treat his infection?
flucloxacillin
A 26 year old woman presents with fever, headache and confusion. She has an HIV infection and has refused to take antiretroviral therapy for the past 4 years. What rapid test should you ask the microbiology laboratory to perform on her serum sample to confirm the likely diagnosis? -
cryptococcal antigen -> cryptococcus neoformans
A 2-day old neonate develops meningitis. The microbio laboratory telephone to report that a Gram stain of her CSF shows Gram- negative bacilli. What is the most likely causative organism?
e coli
The following antimicrobials can be used for the treatment of community acquired pneumonia. Which has activity against Mycoplasma pneumoniae?
doxycycline
(Tetracyclines (eg doxy) and macrolides can be used)
A 76 year old man with a long term indwelling urinary catheter which was changed earlier in the day becomes unwell. He is pyrexial and has been having rigors. He is tachycardic heart rate of 123 bpm, and hypotensive blood pressure 94/62 mmHg. He is known to be colonised with an ESBL producing E.coli Which antimicrobial would be the mast appropriate empiric therapy?
(Carbapenems are used for this = meropenem, imipenem, ertapenem)
Which agent is an Interleukin 6 (IL-6) inhibitor, indicated for treatment of severe COVID-19 infection with hypoxia?
Tocilizumab
(key word here is IL-6 inhibitor)
Which antiviral agent is used for the treatment of Influenza A?
Zanamivir (a neuraminidase inhibitor like oseltamivir. Baloxavir is a polymerase inhibitor that is also used
A 72 year old woman was admitted 6 days ago after a fall, she has had a dynamic hip: screw inserted. She now has evidence of a hospital acquired pneumonia. Which is the most likely causative organism?
Escherichia coli. (enterobacteriae most common cause of HAP)
Blood cultures taken from a 57 year old patient on renal dialysis have grown a glyCOpeptide resistant Enterococcus faecium (gram +ve). Further susceptibilities are to follow. Which antimicrobial is an appropriate choice for initial treatment of this infection?
linezolid
-> resistant to Taicopianin
and Vancomycin