Management of Common Infections

Question 1

Why is combination therapy used?

Answer 1

• synergy
• to prevent resistance
• mixed infection and 1 agent doesn’t cover all bases

Question 2

Define pyrexia of an unknown origin?

Answer 2

fever where the cause remains unknown despite

• history & examination,
• 3 sets of blood cultures & urinalysis
• routine invesigations,
• CXR
• further tests directed by localising symptoms/signs

Question 3

What are the main 3 causes of pyrexia of unknown origin?

Answer 3

• infections
• malignancies
• CT diseases (vasculitis, RA)

Question 4

What are the infective causes of PUO?

Answer 4

TB
Endocarditis
Abscess
Teeth
Back - osteomyelitis
Sinuses
Typhoid
Infected prosthesis

Question 5

What are the rheumatological causes of PUO?

Answer 5

Periodic fever syndrome
Vasculitis
Adult onset Still’s

Question 6

What are the cancerous causes of PUO?

Answer 6

Lymphoma
Renal cell carcinoma
Hepatocellular Carcinoma

Question 7

What medications can cause PUO?

Answer 7

Antibiotics
Anticonvulsants
NSAIDs
Antihypertensives
Antihistamines
Alcoholic hepatitis
Recreational

Question 8

What useful second line tests should you do for PUO?

Answer 8

• ESR
• CRP
• RhF
• Blood film
• serology
• imaging CT
• ECG
• biopsy, bone marrow aspiration

Question 9

What is the prognosis of PUO?

Answer 9

• generally good outcome as get better with steroids/antibiotics
• low mortality
• symptoms gradually subside despite not knowing what is going on

Question 10

Urinary Tract Infections

Answer 10

UTI
Pyleonephiritis
Prostaitis
PID

Question 11

Skin and soft tissue infection

Answer 11

Cellulitis
Necrotising fasciitis
Bites

Question 12

Resp tract Infections

Answer 12

Pneumonia
Empyema
TB
COPD

Question 13

CNS Infections

Answer 13

Meningitis
Encephalitis
Cerebral abscess

Question 14

Abdo Infections

Answer 14

Gastroenteritis
CHolangitis
Hepatitis

Question 15

Bone and joint Infections

Answer 15

Septic arthritis
Osteomyeltiis
Diabetic Foot

Question 16

Cardiovasc Infections

Answer 16

Endocarditis

Device related infection

Question 17

UTIs

Answer 17

• common
• can be asymptomatic to renal abscess/urosepsis
• by organisms which normally reside in GI tract
• more common in woman as shorter urthera so bacteria less distance to travel
• dysuria, bladder tenderness, flank pain, fever, circulatory failure, organ failure
• dipstick, MSU culture, renal US/CT, abdominal CT

Question 18

What is asymptomatic bacteria in UTI?

Answer 18

• no symptoms
• bacteria present
• not need treating excep immunosuppressed, abnormal anatomy of urinary tract, children, pregnancy
• pregnancy can develop pyelonephritis

Question 19

What is proteus?

Answer 19

UTI associated with renal calculi

• breaks down urea to ammonia to alkaline urine to stones
• MSU growing proteins present

Question 20

Things to look out for with UTI

Answer 20

• S. aureus in urine
• endocarditis
• renal abscess in urine
• check renal function before advising nitrofurantoin as won’t get into urine if eGFR <60
• pyelonephritis = prolonged fever

Question 21

Skin and soft tissue infection guidelines

Answer 21

• common
• can be life threatening
• depends on what skin/soft tissue structures involved
• pus present?
• beware around eye, face, fingers, neck, groin/genitals
• if pain disproportionate to degree of damage = deeper infection?

Question 22

Define cellulitis?

Answer 22

• inflammation of cells
• infection of dermis and subcutaneous tissues
• indistinct edge

Question 23

Define erysipelas

Answer 23

• red skin
• infection of dermis only
• clear demarcated edge

Question 24

Deifne impetigo

Answer 24

erythematous patches

associated with serous discharge and golden crust

Question 25

Causes of hot red leg

Answer 25

Cellulitis
DCT
COntact dermatitis
Gout
Drug reaction
Insect bite
Exacerbation of lymphoedema

Question 26

What is important about cellulitis?

Answer 26

Does not exist bilaterally!!

Question 27

RTI guidelines

Answer 27

• over diagnosed
• COPD exacerbations don’t always need ABs as often viral
• sepsis message need urgent ABs
• range anatomically (upper, lower)
• often exacerbations of pre-existing resp conditions
• pathogen range (bac, viral, fungal)

Question 28

Difference between typical and atypical pneumonias

Answer 28

Typical is S pneumonia or H. influenza grown but atypical no organism cultured as non-culturable (legionella, clhamydiphilia, mycoplasma)
- atypical milder, WBC less elevated, hyponatremia?, extra pulmonary manifestations

Question 29

What is the CURB 65 score?

Answer 29

Clinical Judgement 
Assessment of severity of resp infections
- confusion, urea, resp rate, BP, age
- low, moderate, high severity
- low = single AB
- mod = amoxicillin and macrolide
- high = beta lactam and macrolide

Question 30

Define meningitis and presentation

Answer 30

• meninges inflammation

- headache, neck stiffness and photophobia

Question 31

Define encephalitis and presentatin

Answer 31

• brain parenchyma inflamm

- associated with cerebral function = seziures, weakness, behaviour change

Question 32

Difference between viral meningitis and encephalitis

Answer 32

Men does not need treatment but enceph does

- more viral enceph over bacterial

Question 33

CNS Infection guidelines

Answer 33

• sample CSF

- anti-infectives start then cessate

Question 34

Infective endocarditis guide

Answer 34

• positive vs negative culture
• native vs. prosthetic
• indolent vs. acute
• reason for specific organisim may be important as indicates other disease in body
• why that valve? something else wrong with it?
• surgery? depends