Haemolytic uremic syndrome

Question 1

What is the key triad of haemolytic uraemic syndrome?

Answer 1

AKI
Microangiopathic haemolytic anaemia
Thrombocytopenia

Question 2

What is the key aetiology of HUS?

Answer 2

Gastrointestinal illness with a shiga toxin-producing bacteria such as E.coli or shigella.
Inc risk when treated with antibiotics or anti-locomotion

Question 3

What is the key epidemiology of HUS?

Answer 3

Children between 6 months and 5yrs
Rare
10% STEC progress to HUS

Question 4

What are the risk factors for HUS?

Answer 4

Contact with farm animals or their faeces
Eating contaminated food
Swimming or drinking contaminated water
Summer - June to September
Older age or immunsuppression

Question 5

What is meant by atypical HUS?

Answer 5

Around 10% of cases ->most due to underlying complement abnormality that predisposes to complement overactivation
Steptococcus pneumonia, HIV
Pregnancy
Medication - cisplatin, quinine, tacrolimus
Illicit drugs - cocaine and heroin
Autoimmune condition - SLE
Malignancy

Question 6

What are the key symptoms of HUS?

Answer 6

Initial profuse diarrhoes that becomes bloody
Abdominal pain, N+V
HUS - oliguria, fatigue, fevers, chest pain, shortness of breath, headache

Question 7

What are the signs of HUS?

Answer 7

Pallor
Peripheral oedema
Tachypnoea - crackles due to PO
Dehydration - sunken eyes, mucus membranes
Shock
Abdo tenderness
Petechiae
Altered level of consciousness

Question 8

What bedside tests should be done for HUS?

Answer 8

Stool culture or PCR for E.coli
Blood gas - acidosis and hyperkalaemia
Urinalysis - haemturia and protein
Urine MS - rarely STEC UTI
ECG - myocarditis as a complication

Question 9

What blood tests should be done for HUS?

Answer 9

FBC - anaemia and thrombocytopaenia
Blood film - schistocytes - fragmented rbcs
U&Es - raised urea and creatinine, hyperkalaemia
CRP
Reticulocytes and LDh
HB low
Coag norm
Group and save/ crossmatch
Blood culytes

Question 10

What imaging should be done for HUS?

Answer 10

CXR - pulmonary oedema
Renal ultrasound - rule out obstructive AKI

Question 11

What is the management for HUS?

Answer 11

A to E approach
Notifiable disease
Fluid boluses, blood transudsion, hyperkalemia, anti-HTN,
NOT antibiotics
Eculizumab - targets C5 for acute and maintenance treatment