Acute neuromuscular weakness work-up
Screening tests
Serum sodium, potassium, calcium/phosphorus, magnesium
Blood gasses
Liver, renal and thyroid
function tests
Serum CK
Serum cholinesterase levels
CBC, ESR, eosinophil count
Urinalysis
Urine porphobilinogen, d-aminolevulinic acid, myoglobinuria
HIV serology
Toxicoscreening: Urine: thallium, arsenic and tetrodotoxin levels, blood: alcohol levels, serum immunoassay ciguatoxin-1 levels (>0.1 mg/kg), serum saxitoxin levels,
CSF analysis (AIDP),
including lactate
(mitochondrial disorders)
Chest X-ray, ECG
EMG, NCVs and supramaximal repetitive stimulation
EEG (thallium and arsenic poisoning)
Tensilon test
MRI brain and spinal cord including cauda equina (West Nile virus), MRI cervical spinal cord (mimic)
Specific investigations
Blood/serum
ANA
Serum acetylcholine receptor antibodies, VGCC antibodies (LEMS), IgM antibody titers (West Nile virus)
Cultures and serology
Throat cultures (C. diphtheriae), stool cultures (C. botulism)
Lyme serology
Muscle/nerve biopsy