Infectious disease 4 Flashcards
Infectious aortitis cause?
Syphillis (past)
1st - Staphyloccocal and salmonella
2nd - M. bovis from BCG vaccine
If has MDR TB - what test will be positive?
Quantiferon gold - T cell releases IFN-y
T-SPOT - peripheral mononuclear cells releases IFN-y
Quantiferon gold
TB1 measures what?
TB2 measure what?
TB1 - CD4 T cell response
TB2 - CD4 and CD8 T cell response
TB meningitis treatment?
Moxifloxacin ( better CSF penetration)
Dexamethasone - reduces mortality - TB-IRIS
Latent TB treatment?
9 months of Isoniazid OR
4 months of rifampicin
isoniazid
Active TB treatment?
RIPE for 2 months then
RI for 4 months
*Isoniazid - early bactericidal activity
Among TB drugs - which is most potent to cause hepatitis?
Pyrazinamide > isoniazid> Rifampicin
Risk factor highest for latent TB to convert into active TB?
HIV (highest) Solid organ transplant CKD TNF-a Diabetes ( lowest risk)
In which TB - early ART maybe harmful and causes TB-IRIS?
TB meningitis
Paradoxical worsening of TB after removal of biologics happened most with what drug?
Adalimumab > Infliximab
Steroids in TB useful in what situation and not useful in what situation?
Meningeal TB/pericardial TB = improve survival but not morbidity
Pleural TB - faster healing but no effect on morbidity/mortality
Immunity to influenza is due to antibodies against what component?
Hemagglutinin proteins ( it binds to sialic acid)
Neuraminidase function?
Cleave sialic acid and release the virus to neighboring epithelial cells
SIRS definition?
T > 38/ < 36 WBC > 32/ < 4/ or > 10% bands PaCO2< 32 RR > 20 HR > 90
What management in sepsis are questionable?
Albumin - risk of renal failure
Dopamine - increase mortality
Tri-azoles antifungal mechanism?
inhibits C-14a demethylase - for ergosterol synthesis
Principles of anti-fungal - when use;
Neutropenic unstable patient
Neutropenic unstable - Echinocandins ( caspofungins)/ amphotericin
Resistant candidemia - Polyenes (amphotericin)
VRE ;
VanA gene confers resistance towards?
VanB gene confers resistance towards?
VanA = Vancomycin and Teicoplanin
VanB = Vancomyin
VanA gene - how it confers resistance?
Alter peptidoglycan terminus
West nile virus clinical features?
What mosquito species spread it?
Mimics dengue + neuroinvasive = seizures/meningoencephalitis
Culex - Aedes
Coagulase negative Staph - Treatment?
Species for coagulase negative staph?
Vancomycin
Staph epidermidis = axillae/anterior nares/toes
Staph hemolyticus/hominis = axillae
Staph capitis = scalp
Staph lugdunesis = groin/perineum
B-lactam are analogues of?
D alanyl- D alanine
teicoplanin highly effective against?
MRSA
VanB - VRE
VISA
Macrolide mechanism of action?
Stop peptidyl transferase (50s inhibitor) + immunomodulatory = suppress neutrophils/inflammation
Lincosamide mechanism of action?
Stop peptidyl transferase (50s inhibitor)
Antibiotics that are nucleic acid inhibitors?
Nitroimidazoles ( METronidazole) Nitrofurantoin Fluoroquinolones Rifamycins -MET call = NFR
Specific MOA for
Metronidazole
Nitofurantoin
Metronidazole = disrupt DNA and inhibit transcription/translation
Nitrofurantoin = Bacterial flavoproteins metabolise nitrofurantoin = DNA damage
Trimethoprim mechanism of action?
Side effect?
Anti-folate = Dihydrofolate reductase inhibitor
Side effect : Block ENa channel - High K/ High Cr
Sulphonamides ( Sulfamethaxazole) mechanism of action?
Side effect?
Anti-folate = Dihydropteroate synthase inhibitor
Side effect : SJS/TEN/Agranulocytosis
Rifampicin also used in what? ( apart from TB)
Invasive staphlococcal infection - OM/metal hardware infection
Commonest congenital heart defect? - need antibiotic prophylaxis for IE?
Patent Foramen ovale - No