Table 3.
Clinical summaries of VCP mutation carrying patients.
| VCP mutation | R95C | I27V |
|---|---|---|
| Clinical and Laboratory Features | ||
| Duration >12 months | Yes | Yes |
| Age at onset >45 | Yes | Yes |
| Sporadic | Yesb | Yes |
| Slow progression | Yes | Yes |
| Knee extension weakness ≥ hip flexion weakness | Yes | Yes |
| Finger flexion weakness > shoulder abduction weakness | No | Yes |
| Wrist flexion weakness > wrist extension weakness | No | Yes |
| Finger flexion weakness | Yes | Yes |
| Quadriceps ≤ MRC 4 | Yes | Yes |
| Proximal and distal weakness of arms and legs | Yes | Yes |
| CK no greater than 15xULN | Yes (551 u/L) | Yes (914 u/L; nl 30–200 u/L) |
| EMG consistent | Yes | Yes |
| Presence of Anti-NT5C1A | Noa | N/A |
| Pathologic Features | ||
| Endomysial inflammatory infiltrate | Yes | Yes |
| Invasion of nonnecrotic fibers | Yes | Yes |
| Rimmed vacuoles | Yes | Yes |
| Protein accumulation | Yes | N/A |
| 15–18 nM tubulofilaments | N/A | N/A |
| Intracellular amyloid deposits | No | Yes |
| Up-regulation of MHCI | Noa | N/A |
| Diagnostic Criterion | ||
| ENMC 2013 Diagnosis | Probable IBM | Clinico-pathologically defined IBM |
| Griggs Criteria Diagnosis | Possible IBM | Definite IBM |
a
Testing performed after identification of VCP mutation.
b
Two siblings with late onset dementia.