Suggested diagnostic research criteria for critical illness myopathy

Major diagnostic features

1. Sensory nerve amplitudes >80 percent of the lower limit of normal in 2 or more nerves

2. Needle EMG with short-duration, low-amplitude MUPs with early or normal full recruitment, with or without fibrillation potentials

3. Absence of a decremental response on repetitive nerve stimulation

4. Muscle histopathologic findings of myopathy with myosin loss

Supportive features

1. Motor amplitudes <80 percent lower limit of normal in 2 or more nerves without conduction block

2. Elevated serum CK (best assessed in the first week of illness)

3. Demonstration of muscle inexcitability

4. Prolonged compound muscle action potential durations (>8 milliseconds for all nerves except >15 milliseconds for the fibular motor response to the tibialis anterior)

By definition, patients are or were critically ill, and weakness should have started after onset of critical illness. For a definite diagnosis of critical illness myopathy, patients should have all 4 major features and 1 or more supportive features. For probable critical illness myopathy, patients should have any 3 major features and 1 or more supportive feature. For possible critical illness myopathy, patients should have either major features 1 and 3, or 2 and 3, and 1 or more supportive feature.

EMG: electromyography; MUPs: motor unit potentials; CK: creatine kinase.

Graphic 76493 Version 3.0

خرید پکیج

Suggested diagnostic research criteria for critical illness myopathy