Core Microbiology

Question 1

THINK SMART THEN FOCUS. For what?

Answer 1

Antibiotic stewardship

Question 2

State the two most comomonly used antibiotic groups.

Answer 2

B-lactams
Glycopeptides

(both cell wall synthesis inhibitors)

Question 3

Name the other antibiotic groups.

Answer 3

Aminoglycosides - Gentamicin

MLS: Macrolides, Lincosomides, Streptogramins

Tetracyclines
Oxalidinones - Linezolid

(All protein synthesis inhibitors)

Quionolines & Fluroquinolones (DNA synthesis inhibtors

Question 4

What drug amongst others is commonly used to treat TB?

Answer 4

Rifampicin

Question 5

List 8 common side effects of antibiotics

Answer 5

Nausea
Vomiting
Diarrhoea
Skin rash
Allergic reaction
C. dificile
FUNGAL INFECTIONS
RESISTANCE

Question 6

How is antibiotic resistance spread?

Answer 6

Resistance genes in TRANSPOSONS via plasmids

Question 7

Are virus’ intracellular or extracellular organisms?

Answer 7

Intracellular

• Take over cells and replicate itself then releases

Question 8

Examples of chronic viral infections that are latent.

Answer 8

HSV

CMV

Question 9

Whats the common stem in antiviral names?

Answer 9

“-vir-“

Question 10

What are the 2 drugs used to treat Hep C?

Answer 10

Interferons

Ribavirin

Question 11

State the 2 targets in antifungal drugs.

Answer 11

Ergosterol - cell membrane

B-1,3 Glycan - cell wall

Question 12

There are 5 classes of antifungal drugs. What spectrum are they?

Answer 12

All BROAD SPECTRUM

Question 13

What are the 5 classes of antifungal drugs?

Answer 13

Polyenes

Allylamine (inhibit ergosterol synthesis)

Azoles (inhibit ergosterol synthesis)

Echinocandins (inhibit B-1,3 glucan synthase)

Others

Question 14

Amphotericin B is a polyene antifungal. It is used as lipid-associated AmB. Why?

Answer 14

Reduce nephrotoxicity and allergic reactions

• used IV, systemic fungal infections

Question 15

What drug is an allylamine? What is it used for?

Answer 15

Terbinafine

• dermaphtye infections

Question 16

Azoles consist of what 2 subtypes? Which one is less toxic and therefore given IV/oral?

Answer 16

Imidazoles

Triazoles* - Fluconzole, Itraconazole

Question 17

Clotrimazole (in Canistan) is an example of an Imidazole drug. What type of infections is it used for?

Answer 17

Dermaphyte infections

Question 18

What are the 2 adverse effects of azoles?

Answer 18

Heptaotoxicity

Drug interactions - inhibits CYP450 - increases [drugs]

Question 19

Which antigfunals require therapeutic drug monitoring?

Answer 19

5-FC, Itraconzole

Question 20

What are the man ways a child can present with a viral infection?

Answer 20

Fever + rash

Respiratory symptomes

Diarrhoea/Vomiting

Question 21

The “slapped cheek” appearence is caused by what?

What are the other symptoms?

Answer 21

Parovirus B19

Fever + rash
Arthralgia
Respiratory

Question 22

What is a very common virus that causes bronchiolitis in almost all by 1yr?

Answer 22

Respiratory Syncytial virus (RSV)

Question 23

How are most viral infections in children investigated?

Answer 23

PCR

Swab

Question 24

Most viru’s in children are self-limiting and managed supportively, rehydrating. However, some viruses require treatment. Which ones are they and their drugs?

Answer 24

Chicken pox - Aciclovir

Adenovirus - Cidofovir onyl if IMMUNOCOMPROMISED

Measles - antibiotics only if SUPERINFECTION

Question 25

What are examples of Helminth infections?

Answer 25

Schistosomiasis Ascariasis Hydatid disease

Question 26

Ascariasis has is causes by an intestinal worm and has 2 phases. What are they?

Answer 26

INTESTINAL PHASE LUNG MIGRATION: Loefflers syndrome = dry cough, SOB, wheeze, haemoptysis

Question 27

Albendazole is used to treat what parasitic infection?

Answer 27

Ascariasis A for Albendazole

Question 28

What helminth infections presents as 1. swimmers itch 2. Katayama fever - reaction when worm enters blood 3. (Chronic...)

Answer 28

Schistosomiasis

Question 29

What are the complications of Schistosomiasis?

Answer 29

Bladder problems --> cancer Liver cirrhosis

Question 30

What infection is caused by Enchinococcus and produces cysts in LIVER/lungs?

Answer 30

Hydatid disease

Question 31

If untreated schistosomias can become chronic. What is the treatment?

Answer 31

Praziquantel

Question 32

Malaria and Crytosporidiosis are examples of what?

Answer 32

Protozoal parasitic infections

Question 33

What acroynm is used to remember the clincal presentation of malaria?

Answer 33

FALCIPARUM ``` Fever AKI Low sugar Confusion, coma I - DIC Pulmonary odema Anameia, abdo Retinopathy Metabolic acidosis ```

Question 34

How would malaria be investigated?

Answer 34

Serology PCR

Question 35

Cryptosporidiosis is contracted by the faecal-oral root like Ascariasis. What symptoms?

Answer 35

Watery diarrhoea Non-spefiic GI: nausea, vomiting, fever, bloating, cramps

Question 36

Treatment for Cryptosporidiosis?

Answer 36

Fluids Nitrazoxanide

Question 37

How are most parasitic infections investigated?

Answer 37

Stool sample Serology

Question 38

Whch viral infection is characteristised as 3C's + erythematous rash + fever? When is it infective?

Answer 38

Measles 4 days pre-rash --> 4 days post-rash

Question 39

Which common infection presents as fever + rash + foot/mouth/hand disease, that needs to EXCLUDE MENINGITIS?

Answer 39

Enteroviral infections

Question 40

Adenovirus is common in children and adults. What are the 3 main symptoms?

Answer 40

Mild URTI Conjunctivitis Diarrhoea

Question 41

Which 2 common viruses present as vomitting and diarrhoea?

Answer 41

Rotavirus Norovirus (PCR, Rehydration)

Question 42

List some antibitoics suitable for those with penicillin allergies.

Answer 42

Erythromycin Clarithromycin Vancomycin Linezolid

Question 43

# Define the following terms: - Bacteristatic - Bactericidal - Minimum inhibitory [c]

Answer 43

Bacteristatic = inhibit growth (protein synthesis inhibitors) Bactericidal = kill bacteria (cell wall agents) MIC - minimum [antibiotic] visibly inhibiting growth

Question 44

β-lactam/aminoglycoside to treat Strep Endocarditis is an example of what?

Answer 44

Synergism | 2 antibiotics given together > sum of individual

Question 45

Which component of bacteria cell wall is in both gram +ve/-ve? Which 2 drugs inhibit cell wall?

Answer 45

Peptidoglycan B-lactams Glycopeptides

Question 46

Quinolones e.g. Ciprofloxacin, Fluroquinolones, Trimethoprim have a mode of action of what?

Answer 46

DNA synthesis inhibitors

Question 47

Which antibiotics are protein synthesis inhibitors? (bacteristatic)

Answer 47

Aminoglycosides (G) MLS Tetracyclines Oxazolidinones

Question 48

Rifampicin is an RNA synthesis inhibitor. T/F?

Answer 48

T

Question 49

The 4C's represent COMMON precipitating antibiotics for C.dif. What are they?

Answer 49

Co-amoxiclav Cephalosporins Ciprofloxacin Clindamycin ANY ANTIBIOTICS CAN CAUSE C.DIF

Question 50

Key antibiotics for specific infections...?

Answer 50

Flucloxacillin - S. aureus (not MRSA) Benzylpenicillin – S.pyogenes Cephalosporins (avoid in elderly) – Gram-ve bacilli Metronidazole – anaerobes Vancomycin – Gram-positives (MRSA) Meropenem – most clinically-relevant bacteria Colistin – last option for multi-resistant Gram-negatives

Question 51

State reasons for combining antibiotics.

Answer 51

1. Increase efficacy 2. Provide adequate broad spectrum 3. Reduce resistance

Question 52

The anti-virals NRTIs consist of Pyrimidine/ Purine analogues. Zidovudine and Lamivudine are examples of what?

Answer 52

Pyrimidines | Abacavir, Tenofovir for purine analogues

Question 53

Nevirapine, Efavirenz are examples of which anti-viral?

Answer 53

NNRTIs

Question 54

What antibiotics is last line for multi-resistant enterococci?

Answer 54

Meropenem

Question 55

Common drug used to treat CMV?

Answer 55

Ganciclovir