rhabdomyolysis

Question 1

what is rhabdomyolysis?

Answer 1

skeletal muscle breakdown releases myoglobin (+CK, K, PO4, urate) which are toxic to kidneys
produce AKI
raised creatinine kinase x5ULN + maybe raised potassium

Question 2

what are the causes of rhabdomyolysis?

Answer 2

ischaemia- embolism, surgery

trauma- immobilisation, crush injury, burns, seizures, compartment syndrome

toxins- statins (Esp co-prescribed w clarithromycin), fibrates, ecstasy, neurleptics

genetic- mcardle’s syndrome - genetic disorder that effects skeletal muscle

Question 3

what is the clinical presentation of rhabdomyolysis?

Answer 3

AKI 10-12hrs later, Cr x5 ULN
muscle pain, swelling
myoglobinuria- red/brown urine

Question 4

what investigations suggest rhabdomyolysis?

Answer 4

blood- raised CK, K, PO4 + urate, possibly metabolic acidosis, hypocalcaemia
dipstick- positive hb, negative rbc

Question 5

what is the management of rhabdomyolysis?

Answer 5

IV fluids to maintain good urine output
treat hyperK
urinary alkalinisation sometimes- IV NaHCO3

Question 6

why do you get raised phosphate levels in rhabdomyolysis?

Answer 6

released from myocytes

Question 7

why do you get hypocalcaemia in rhabdomyolysis?

Answer 7

myoglobulins bind calcium