Gastroenteritis, Cellulitis, Infective Endocarditis

Question 1

Clinical features of gastroenteritis?

Answer 1

Short history

Diarrhoea (a lot)
Vomiting
Fever
Malaise, myalgia

Dehydration: thirst, dry mucous membranes, dizziness, weakness

Question 2

If a patient with type 2 diabetes presents with diarrhoea and generally unwell, what should you make sure you check?

Answer 2

BMs

He could have hyperglycaemic hyperosmolar non-ketotic state

A condition that is precipitated by infection, MI etc.

Results in hyperosmolality, hypernatraemia, decreased consciousness

Question 3

What is HONK?

Clinical features?
Management?

Answer 3

Hyperglycaemic hyperosmolar non-ketotic state

A condition that affects people with type 2 diabetes

Precipitated by MI, infection

Causes hyperosmolality and hypernatraemia
Decreased conscious level

Management: fluid replacement, stop metformin, insulin

Question 4

Which drugs put a dehydrated patient at more risk of AKI?

Answer 4

Metformin
PPI (lanzoprazole)
ACEi
NSAIDs
Diuretics
Aminoglycosides (gentamicin)

Question 5

Investigations of gastroenteritis?

Answer 5

Bedside:

• BM
• Obs
• ABG, VBG

Routine:

• Bloods: FBC, UE, LFTs, TFTs, Clotting, CRP
• Cultures: blood, stool
• AXR

Specialist:

• MRI
• CT
• Scopes

Question 6

List some pathogens that cause diarrhoea.

What would you see in the history with these pathogens?

Answer 6

Salmonella

Shigella: bloody diarrhoea

Campylobacter: commonly from chicken

E. coli: salads

Hep A: shellfish
Hep E: pork
(these usually have longer incubation period)

Question 7

What should you worry about in an E. coli GI infection?

Explain it!

Answer 7

E. coli 0157

Can lead to haemolytic uraemic syndrome

Triad of:

1. anaemia
2. uraemia (AKI)
3. thrombocytopenia

A toxin released by the bacteria binds to receptors in renal and CNS tissue and causes damage

Question 8

Management of gastroenteritis?

Answer 8

Supportive

Oral rehydration solution

Anti-emetics and anti-diarrhoeals

You only give antibiotics if:

• bacteraemia
• severe infection
• immunocompromised
• C. diff

Question 9

Which antibiotics do you give in these situations?

Answer 9

Bacteraemia:

• amoxicillin to cover salmonella
• azithromycin to cover campylobacter

C. diff: metronidazole, 2nd line PO vanc

Question 10

What are the public health rules associated with infective gastroenteritis?

Answer 10

Notify public health England

If they work in food handling, hospitals, with vulnerable people wait 48hrs after last episode

Trace back to the cause of infection, like if its a shop or restaurant

Question 11

List some skin infections and say which part of the skin is involved.

Answer 11

Cellulitis: dermis and subcutaneous tissue

Erysipelas: dermis and upper subcutaneous tissues

Folliculitis: hair follicle, leading to a boil

Impetigo: superficial

Necrotising fasciitis: skin and deeper fascia

Question 12

Clinical features of cellulitis?

Erysipelas?

Answer 12

Cellulitis:

• poorly demarcated
• blisters and bullae
• systemic unwell

Erysipelas:

• well demarcated
• red, tense, shiny, bullae
• systemic unwell

Question 13

Which bugs usually cause:

• folliculitis
• impetigo?

Answer 13

Folliculitis: s. aureus

Impetigo: s. aureus or s. pyogenes

Question 14

Differential diagnosis of cellulitis?

Answer 14

Erysipelas
DVT
Septic arthritis or osteomyelitis
Dermatitis
Vasculitis
Gout
Chronic venous insufficiency

Question 15

Why are diabetic patients predisposed to cellulitis?

Answer 15

Type 1 diabetics have a weakened immune system

Peripheral neuropathy: may not feel an injury so high chance it could get infection

Sugary blood = good for bacterial growth

Chronic hyperglycaemia can affect activity of immune system (neutrophils, phagocytes etc.)

Question 16

What are some risk factors for cellulitis?

Answer 16

Previous cellulitis or erysipelas
Venous insufficiency
Diabetes
Alcohol excess
IVDU
Lymphoedema
Obesity
Pregnancy
Athletes foot

Question 17

Investigations of cellulitis?

Answer 17

Bedside:

• BM
• Obs
• urinalysis (if they’re diabetic and unwell, high chance of DKA)

Routine:

• Bloods: FBC, UE, LFTs, CRP, Clotting, ketones
• Cultures: blood, swab of wound, between toes
• XR

Specialist:

• fine needle aspiration of leading edge of lesion
• MRI
• CT

Question 18

Which pathogens cause cellulitis?

Answer 18

Bugs that colonise the skin

Strep: beta-haemolytic - group A (pyogenes) and group C and G

Staph aureus

Anaerobes can too but these arrive by haematogenous spread

Others

• Klebsiella
• moraxella
• psuedomonas
• clostridium perfringens

Question 19

Management of cellulitis?

Answer 19

Flucloxacillin: covers B-haemolytic strep and s. aureus

PO or IV

Supportive: analgesia

NSAIDs and corticosteroids reduce recovery time

Question 20

When should you refer a case of cellulitis to hospital?

Answer 20

If you suspect nec fasc
Severe or rapidly worsening
Systemically unwell
Complications
Facial infection
Immunocompromised
Diabetic
Child under 1
Frail
Lymphoedema

Question 21

Clinical features of necroitising fasciitis?

Which bug?

Answer 21

Infection of skin and deep fascia

Cuts of blood supply leading to necrosis

Severe systemic toxicity

Rapidly spreading
Crepitus if organisms produce gas

S. pyogenes

Question 22

Clinical features of infective endocarditis?

Answer 22

FEVER AND NEW MURMUR

Often mitral regurgitation, early diastolic murmur

Fever and chills
Malaise
Myalgia
Anorexia
Weight loss
Abdominal pain
Nausea and vomiting

CCF: SOB, orthopnoea, PND

Splinter haemorrhages
Roth’s spots (retinal haemorrhages)

Emboli to brain, lung, spleen

Question 23

What is the most common murmur in IE patients?

Answer 23

Aortic regurgitation

Which is an early diastolic murmur

Question 24

What are some signs in the hands of IE?

Answer 24

Splinter haemorrhages

Osler’s nodes: small nodules on pulp of phalanges

Janeway’s lesions: painless erythematous macules on the thenar and hypothenar eminence

Question 25

What might you find on examination of a patient with IE?

Answer 25

A new murmur: often early diastolic (A. regurg)

Petechiae: conjuctiva, hands and feet, chest, abdo, oral mucosae

Splinter haemorrhages

Osler’s nodes
Janeway lesions

Arthritis

Splenomegaly

Meningism / meningitis

Question 26

Investigations of IE?

Answer 26

Bedside:

• Obs
• BM
• ABG, VBG
• Trans thoracic echo
• Urinalysis

Routine:

• Bloods: FBC, UE, CRP, LFT, Clotting
• Blood cultures
• CXR

Specialist:

• trans-oesophageal echo
• CT, MRI

Question 27

Risk factors for IE?

Answer 27

Valvular heart disease

Valve replacement

Structural congenital heart disease

Previous IE

Hypertrophic cardiomyopathy

IVDU

Invasive vascular procedures

Question 28

Pathogenesis of IE?

Answer 28

Starts off with a sterile fibrin-platelet vegetation (thrombus)

Which then gets infected

Question 29

Which valves are most commonly affected in IE?

Answer 29

Mitral valve
Aortic valve
Both

Question 30

Which organisms cause IE?

Answer 30

Staph. aureus (most common)

Strep:

• viridans
• group A, B, C, G
• intermedius

Psuedomonas

Kingella kingae, Haemophilus species, cardiobacterium species

Fungi

Question 31

What complications can IE cause?

Answer 31

Meningitis

Emboli in brain: middle cerebral artery, causing hemiplegia

Renal infarcts - painless haematuria
Nephritis
AKI

Splenic infarct - pain

MI
CCF
Pericarditis

Retinal artery occlusion - blindness

Pulmonary emboli

Synovitis

Back pain: immune complex deposition in disc spaces

Question 32

What’s the antibiotic management of IE?

Answer 32

IV abx for 4 weeks (6 weeks if prosthetic valve)

Staph confirmed:

• Fluclox for non-MRSA
• Vancomycin and rifampicin for MRSA

Strep confirmed:

• BenPen
• Ceftriaxone
• Gentamicin

Question 33

Management of IE?

Answer 33

Antibiotic therapy
- IV, 4 weeks, 6 weeks for prosthetic

Surgical: if prosthetic valve or if severe IE with CCF in native valve