Infectious Diseases

Question 1

list some organisms that are unculturable

Answer 1

legionella, mycoplasma, chlamydia

Question 2

example of gram positive rods (purple stain)

Answer 2

bacillus, clostridium, listeria

Question 3

examples of gram positive cocci (purple staining)

Answer 3

Staphylococci (clusters): 
staph aureus (coagulase +ve)
staph epidemidis (coag -ve)

streptococci (chains):

s. pneumoniae (diplococci)
s. viridans (long chain)
s. pyogenes (beta haemolytic)

Question 4

examples of gram negative rods (pink stain)

Answer 4

Gut and GU bacteria - shigella, e.coli, pseudomonas, klebsiella

Question 5

examples of gram negative cocci (pink stain)

Answer 5

H. influenza

Neisseria (gonorrhea and meningitis)

Question 6

which Abx work on ribosomes/ affect protein synthesis

Answer 6

MCAT

Macrolides (clarithromycin)
chloramphenicol
aminoglycosides (gentamicin)
tetracyclines (doxy)

used more for atypical organisms/ unculturables

Question 7

how do quinolones work?

Answer 7

inhibit DNA synthesis so broad spectrum (ciprofloxacin)

Question 8

examples of cell wall inhibitors

Answer 8

glycopeptides (vanc), beta lactams (penicillin)

Question 9

what is vancomycin used for

Answer 9

MRSA

Question 10

list the beta lactam Abx (examples and uses)

Answer 10

penicillin (amox) - gram positive
cephalosporin (ceftriax/cephalex) - broad spec for +ve and -ve
carbapenems (meropenem) - broad spec, +ve, -ve and anaerobic

Question 11

management of uncomplicated UTI in a woman and cautions

Answer 11

3/7 trimethoprim (folic acid metabolism)

pregnancy and methrotrexate

Question 12

management of UTI in men/pregnant women

Answer 12

7/7 nitrofurantoin

Question 13

management of Hep B

Answer 13

IFN alpha, tenofovir, lamivudine

Question 14

management of Hep C

Answer 14

sofobsuvir

Question 15

what are the typical pneumonia organisms and associations

Answer 15

s. pneumoniae
H. influenza - COPD
klebsiella - alcoholics
= amoxicillin / clarithro if allergic
staph aureus - flu, cavitating lesion = fluclox

Question 16

list some atypical organisms in pneumonia and associations

Answer 16

legionella - low sodium (urine antigen)
mycoplasma - erythema multiforme
= clarithromycin

pseudomonas in CF
aspergillus and pneumocystis jiroveci in HIV

Question 17

considerations when prescribing clarithromycin

Answer 17

stop statin and warfarin

Question 18

x ray finding in primary TB

Answer 18

ghon focus in lower lobes - granuloma

not usually symptomatic

Question 19

x ray findings in secondary TB

Answer 19

cavitating lesions

as well as symptoms

Question 20

advice on contraception with rifampicin

Answer 20

reduces efficacy of pill

Question 21

diagnosis of osteomyelitis

Answer 21

MRI - erosions

Question 22

difference between erysipelas and cellulitis

Answer 22

erysipelas more superficial, well demarcated

Question 23

causes of C. diff and management

Answer 23

ciprofloxacin, co-amox, cephalosporin, clindamycin
barrier nurse
metronidazole and oral vanc

Question 24

presentation of clostridium botulinum

Answer 24

canned food

descending paralysis

Question 25

common GI parasitic infection in institutionalised people

Answer 25

giardia

Question 26

best Abx for treating GI infection

Answer 26

metronidazole - anearobic

Question 27

what serology will a Hep B vaccinated person have

Answer 27

raised surface antigen as this is what is in the vaccine | normal surface, core (IgG/Igm), and viral load (HBeAg)

Question 28

what serology will a Hep B exposed person have

Answer 28

raised surface antibody and core - IgG | these are chronic phase indicators but normal viral load (HBeAg)

Question 29

what serology will a Hep B carrier have

Answer 29

positive surface antigen and antibody, core - IgM, viral load (HBeAg) negative for IgM as this is acute

Question 30

what serology will a person with acute Hep B have

Answer 30

positive surface antigen (not yet made antibodies), core-- IgM (not yet chronic so no IgA), high viral load (HBeAg)

Question 31

list the herpes viruses and what they cause

Answer 31

``` 1/2 - ulcers, encephalitis 3 - chickenpox 4- EBV (glandular fever, burkitts) 5- CMV 6- roseola infantum 8 - kaposi's sarcoma ```

Question 32

what finding do you get on CT head in toxoplasmosis

Answer 32

ring enhancing lesion

Question 33

investigations in malaria

Answer 33

``` thick and thin (find what species) blood films RDT antigen test LFTs FBC platelets ```

Question 34

management of malaria

Answer 34

acute - IV artesunate and fluids falciparum - doxycycline and quinine other types - chloroquine

Question 35

causes of meningitis

Answer 35

N. meningitidis H. influenza S. pneumoniae

Question 36

investigations and findings in meningitis

Answer 36

LP (if red flags for raised ICP do CT head) bacterial: low glucose, high protein, high neutrophils viral: normal glucose, low protein, high leucocytes TB: very high opening pressure

Question 37

management of meningitis

Answer 37

empirical benpen IV ceftriaxone prophylaxis - ciprofloxacin

Question 38

investigations , monitoring and findings in HIV

Answer 38

initially: PCR, P24 antigen, IgG/IgM (not in first 3 months), CD4 CD4: monitor every 3/12. normal is 450-1600 also monitor viral load and RNA every 3 months

Question 39

what opportunistic infections do HIV sufferers get with different CD4 counts

Answer 39

any: TB <200: p. jivoreci, toxoplasma (co-triamxoazole) <50: MAI (clarith), CMV retinitis, cryptococcus

Question 40

list some aids defining illnesses

Answer 40

opportunistic infections oesophageal candidiasis sentinel tumours: kaposi's sarcoma, NHL, burkitt's lymphoma, cervical ca (HPV 16,18,33)