Infectious Diseases

Question 1

Antibiotics for TB

Answer 1

rifampicin and isonaizid for 6 months; pyrazinamide and ethmabutol for 2 months;

Question 2

Antibiotics to consider to treat VRE infection

Answer 2

teicoplanin: however Van A resistatn to teicoplanin, commmon in australia linezolid: side effects include anemia, thrombocytopenia; serotonin syndrome; tigecycline: side effects: nausea and vomiting; daptomycin

Question 3

antibiotics with activity against MRSA

Answer 3

vancomycin ciprofloxacin linezolid rifampicin and fusidic acid tigecycline teicoplanin

Question 4

Antifungals: classes; mechanism of action; examples

Answer 4

Triazoles: mech: inhibits ergesterol synthesis in fungal cell wall: i.e fuconazole; voriconazole; Polyenes: mechanism: creates channel in cell wall for cytosol leakage; i.e amphtoericin; nystatin; Echinocandin: mech: inhibit synthesis of D-glucan a cell wall compononet; i.e caspofungin

Question 5

Biochemical markers to differentiate between infectious and non infectious causes of fever

Answer 5

(I think all increased in infectious) Procalcitonin ANP (atrial natriuretic peptide) IFN- y soluble triggering receptor expressed on myeloid cells CRP lipopolysacharide binding protein

Question 6

Diagnosis of CMV

Answer 6

Viral cultures: obsolete; slow and not sensitve Antigenemia: detection of CMV protein PP65 Viral PCR: fast and high sensitivity but not standardised

Question 7

dosing adjustment and monitoring in renal dysfunction for aminoglycosides; penicillins; glycopeptides; carbepenems; quinolone;

Answer 7

aminglycosides: high initial dose; monitor trough dose; may need to extend dosing interval and decrease dose penicillins: may need to extend interval or decrease dose carbepenems: may need to extend itnerval or decrease dose: glycopeptides: high initial dose; monitor trough level; quinolone: reduce freqeuncy

Question 8

Example of gram negative cocci

Answer 8

Neiserria meningitides

Question 9

example of gram positive bacillus

Answer 9

Aerobes: Listeria; Bacillus (spore forming); Antrhrax(spore forming) Anaerobes: Clostridium difficile

Question 10

Investigations to order in case of fungal infection

Answer 10

Echo: look for vegetations ophthlamic review: retinal abscesses CT /Abdo US for liver abscess

Question 11

Markers of severity in C.diff enterocolitis

Answer 11

Fever>38.5 WCC>15 Decreased albumin increased lactate acute kidney injury hemodynamic instability

Question 12

Measures to increase solute clearance in CVVHDF

Answer 12

increase blood flow rate increase dialysate flow rate increase membrane surface area change composition of dialysate fluid to increase concentration gradient

Question 13

mechanisms of antibiotic resistance for VRE

Answer 13

beta lactamase production penicillin binding protein mutations aminoglycoside modifying enzymes antibiotic drug effleux pumps atlerations in cell wall componenets, coded by transposons (coded Van a to F)

Question 14

name the organisms that are ESCAPPM

Answer 14

enterobacter; serratia citrobacter acinetobacter; proteus providencai morganella

Question 15

Name the quinolones; macrolides; lincosamides and there mechanism of action

Answer 15

quinolones: ciprofloxacin; moxifloxacin; mech: DNA gyrase inhibitor macrolides: erythromycin; azyithromcyin; ribosomal 50s subunit inhibition lincosamides; lincomycin; clindamycin; ribosomal 50s subunit inhibtion

Question 16

Pathogenesis of toxic shock syndrome

Answer 16

exotoxin from staph (similar to one from strep) cauese direct activation of T cells leading to massive cytokine production

Question 17

Risk factors for C.difficile enterocolitis

Answer 17

Age>65 immunosuprresion broad spectrum antibiotic use gastrci acid suprresion GI surgery prolonged hospitalisation renal impairment

Question 18

Risk factors for CMV infection in immunocompetent patients

Answer 18

mechanical ventilation bacterial pneumonia + sepsis immunomodualroy effect of RBC transfusion Steroid use: unclear Burns patients

Question 19

Risk factors for development of VRE

Answer 19

Previous antibiotic use; increased LOS; resident of care facility; renal impairment; enteral feeding; prevalence of VRE colonised patients in the unit; long term iv access;

Question 20

Risk factors for fungal infection

Answer 20

Antibiotic use; immunosuppression; Invasive lines/devices; TPN; cancer; pancreatitis; bowel perforation;

Question 21

risk factors for pneumococcal infection

Answer 21

extremes of age COPD; CCF immunnosuppresion; DM trasnplant; asplenia: functional or anatomic; Cochlear implant CSF lerak

Question 22

Risk factors for pneumonai from Zoster

Answer 22

Smoker Immunosuprssion Contact with index case >100 spots chronic lung diease 3rd trimester pregnancy

Question 23

treatment of malaria

Answer 23

plasmodium falciparum: quinine and artemisin plasmodium vivax: chloroquine and primaquine