Medicine - Infectious Diseases

Question 1

which classes of antibiotic have a beta-lactam ring?

Answer 1

• penicillins
  -carbapenems
  -cephalosporins

Question 2

stepwise approach to picking ABx in hospital?

Answer 2

• start empirically with amoxicillin (covers streptococcus, listeria and enterococcus)
• switch to co-amoxiclav (all of above plus staphylococcus, haemophilus and e. coli)
• switch to tazocin (plus pseudomonas)
• switch to meropenem (plus ESBLs)
• add on teicoplanin / vancomycin (covers MRSA)
• add clarithromycin / doxycycline (covers atypical bacteria)

Question 3

pathophysiology of sepsis?

Answer 3

• cytokines trigger a huge immune response
• nitrous oxide gives vasodilation
• coagulation system gets activated, causes DIC
• hypoxia occurs, causing anaerobic respiration and blood lactate rises

Question 4

what are the 2 ways in which septic shock can be defined?

Answer 4

• systolic BP <90 despite fluid resus
• lactate >4 mmol/l

Question 5

management of septic shock?

Answer 5

-aggressive fluid resus
-ICU admission
-inotropes (noradrenalin)

Question 6

features of severe sepsis?

Answer 6

• hypoxaemia
• oliguria
• AKI
• thrombocytopenia
• coagulation dysfunction
• hypotension
• lactate >2 mmol/l

Question 7

risk factors for sepsis?

Answer 7

-extremes of age
-chronic disease (e.g. COPD, DM)
-surgery
-recent trauma / burns
-pregnancy / peripartum
-indwelling catheter / central line

Question 8

which signs make up the NEWS?

Answer 8

-temp
-HR
-RR
-O2
-BP
-GCS

Question 9

signs O/E in sepsis?

Answer 9

-signs of source of infection (cellulitis, wound discharge, cough, dysuria)
-non-blanching rash
-reduced UO
-mottled skin
-cyanosis
-arrhythmias (e.g. new AF)

Question 10

what is often the first sign of sepsis?

Answer 10

high RR (tachypnoea)

Question 11

how might elderly patients present with sepsis?

Answer 11

-confused
-drowsy
-“off legs”

Question 12

which pts might have normal obs even if they are severely septic?

Answer 12

• neutropenic pts
• immunosuppressed pts

Question 13

investigations for sepsis?

Answer 13

take 3: blood culture, lactate, urine output
Give 3: abx, o2, fluids

Question 14

what does BUFALO stand for?

Answer 14

blood cultures (take)
urine output (take)
fluids (give)
ABx (give)
lactate (take)
O2 (give)

Question 15

define neutropenic sepsis

Answer 15

sepsis in a pt with a neutrophil count less than 1 * 10^9 /L

Question 16

drugs which cause neutropenia? give an indication for each of them

Answer 16

chemotherapy (Ca)
clozapine (schizophrenia)
hydroxychloroquine (RA)
methotrexate (RA)
sulfasalazine (RA)
carbimazole (hyperthyroidism)
quinine (malaria)
infliximab (immunosuppression)
rituximab (immunosuppression)

Question 17

when should you suspect neutropenic sepsis?

Answer 17

• have a high index of suspicion
• any fever >38C is neutropenic sepsis until proven otherwise

Question 18

ABx of choice in neutropenic sepsis?

Answer 18

tazocin (piperacillin with tazobactam)

Question 19

what is the difference between meningitis and meningococcal septicaemia?

Answer 19

• meningitis is inflammation of the meninges
• meningococcal septicaemia is when the meningococcus bacteria is in the blood stream

Question 20

unique feature of meningococcal septicaemia? what causes this?

Answer 20

• non-blanching rash
• it is the result of DIC and subcut haemorrhages

Question 21

what are the most common causative organisms of bacterial meningitis in non-neonates?

Answer 21

• n. meningitidis (meningococcus)
• strep. pneumoniae (pneumococcus)

Question 22

what is the most common causative organism in neonatal bacterial meningitis?

Answer 22

group B streptococcus (GBS)

Question 23

presentation of meningitis?

Answer 23

fever
neck stiffness
vomiting
headache
photophobia
altered consciousness
seizures