Table 1.

Clinical criteria for the diagnosis of MMN⁸

Core (both criteria required)

1. Slowly progressive or stepwise progressive, focal, asymmetric limb weakness; that is, motor involvement in the motor nerve distribution of at least two nerves for more than 1 month. If symptoms and signs are present only in the distribution of one nerve, only a possible diagnosis can be made.

2. No objective sensory abnormalities except for minor vibration sense abnormalities in the lower limbs.

Supportive

3. Predominant upper limb involvement.

4. Decreased or absent tendon reflexes in the affected limb.

5. Absence of cranial nerve involvement.

6. Cramps and fasciculations in the affected limb.

7. Response in terms of disability or muscle strength to immunomodulatory therapy.

Exclusion criteria

8. Upper motor neuron signs.

9. Marked bulbar involvement.

10. Sensory impairment more marked than minor vibration loss in the lower limbs.

11. Diffuse symmetric weakness during the initial weeks.

Note: Copyright © 2010 Peripheral Nerve Society. Reproduced with permission from John Wiley & Sons, Inc. Joint Task Force of the EFNS and the PNS. European Federation of Neurological Societies/Peripheral Nerve Society guideline on management of multifocal motor neuropathy. Report of a joint task force of the European Federation of Neurological Societies and the Peripheral Nerve Society – first revision. J Peripher Nerv Syst. 2010;15(4):295–301.

Abbreviation: MMN, multifocal motor neuropathy.