Reductions in muscle quality and quantity in chronic inflammatory demyelinating polyneuropathy patients assessed by...

Weakness in patients with chronic inflammatory demyelinating polyneuropathy (CIDP) may be caused by decreases in muscle quantity and quality, but this has not been explored.

Twelve patients with CIDP (mean age 61 years) and 10 age-matched (mean age 59 years) control subjects were assessed for ankle dorsiflexion strength, and two different MRI scans (T1 and T2) of leg musculature.

Isometric strength was 36% lower in CIDP patients compared with controls. Tibialis anterior muscle volumes of CIDP patients were smaller by ∼17% compared with controls, and non-contractile tissue volume was ∼58% greater in CIDP patients. When normalized to total muscle or corrected contractile volume, strength was ∼29% and ∼18% lower, respectively, in CIDP patients.

These results provide insight into the structural integrity of muscle contractile proteins and pathologic changes to whole-muscle tissue composition that contribute to impaired muscle function in CIDP. Muscle Nerve 58: 396-401, 2018.