Table 1.
Clinical phenotypes of 15 affected individuals
| Patient | III-4 | III-6 | III-8 | III-11 | III-13 | III-16 | IV-3 | IV-5 | IV-7 | IV-8 | IV-9 | IV-10 | IV-11 | IV-13 | IV-14 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sex/current age (yrs) | M/52 | M/52 | M/48 | F/45 | F/41 | M/33 | M/31 | F/18 | M/15 | F/11 | F/18 | M/16 | F/15 | M/15 | F/11 |
| Age of onset (yrs)a | 12 | 11 | 10 | 12 | 13 | 9 | 10 | 12 | 10 | 9 | 13 | 12 | 14 | 5 | 7 |
| Disease duration (yrs) | 40 | 41 | 38 | 33 | 28 | 24 | 21 | 6 | 5 | 2 | 5 | 4 | 1 | 10 | 4 |
| Muscle weakness | D>P | D>P | D>P | Distal | Distal | Distal | Distal | Distal | Distal | Distal | Distal | Distal | Distal | Distal | Distal |
| Distal muscle atrophy | Severe (L>U) | Severe (L>U) | Severe (L>U) | Severe (L>U) | Moderate (L>U) | Moderate (L>U) | Severe (L>U) | Mild (L>U) | Mild (L>U) | Absent | Mild (L>U) | Mild (L=U) | Absent | Mild (L>U) | Mild (L=U) |
| Sensory loss | − | − | ± | − | − | − | − | − | − | − | − | − | − | − | − |
| Hearing loss | NA | + | + | + | + | − | NA | NA | − | − | − | − | − | + | NA |
| Hoarseness | + | + | + | + | + | − | + | − | − | − | − | + | − | + | − |
| Cardiac involvement | NA | − | − | − | − | − | NA | NA | − | − | − | − | − | − | − |
| Foot deformity | + | + | + | + | + | + | + | + | − | − | − | + | − | + | − |
| Knee jerk reflex | Areflex | Areflex | Areflex | Areflex | Areflex | Areflex | Areflex | Normal | Normal | Normal | Normal | Hyporeflex | Normal | Hyporeflex | Normal |
| Additional symptom | − | Seizure | Tremor | − | − | Tremor | Tremor | Arthritis | − | − | − | Seizure | − | − | − |
| Creatine kinase (IU/L)b | NA | WNL | 2.5 fold | WNL | WNL | 1.4 fold | NA | NA | WNL | WNL | WNL | 1.3 fold | WNL | 2.1 fold | NA |
| Lactic acid (mg/dl)c | NA | 13.0 | NA | 19.0 | 9.0 | 11.0 | NA | NA | NA | NA | 10.0 | 13.0 | 7.0 | 12.0 | NA |
| Pyruvic acid (mg/dl)d | NA | 0.5 | NA | 1.0 | 0.7 | 0.7 | NA | NA | NA | NA | 0.7 | 1.1 | 0.6 | 0.7 | NA |
| MRI of lower limbe | |||||||||||||||
| Leg | NA | 3.9±0.3 | 3.6±0.5 | 3.4±0.8 | 3.5±0.6 | 2.5±0.9 | NA | NA | 0.2±0.4 | 0.1±0.3 | 0.3±0.5 | 0.2±0.4 | 0.1±0.3 | 0.8±1.0 | 0.3±0.5 |
| Thigh | NA | 1.4±0.7 | 1.1±0.6 | 0.4±0.5 | 0.3±0.4 | 0 | NA | NA | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Muscle biopsyf | NA | Groupingg | NA | NA | NA | Groupingg | NA | NA | NA | NA | NA | NA | NA | NA | NA |
Abbreviations: D = distal muscle; L = lower limb; NA = not available; P = proximal muscle; U = upper limb; WNL = within normal limit; +/− = positive or negative finding; ± = equivocal finding.
a
Age at onset of distal muscle muscle weakness.
b
Creatine kinase values are listed in relations to the upper limits of normal for our laboratory.
c
Reference range: each 4.5–14.4 mg/dl
d
Reference range: each 0.3–0.9 mg/dl.
e
Degree of fatty infiltration was graded as five-point scale (mean±S.D.).
f
Muscle biopsy was done at vastus lateralis (III-6) and at gastrocnemius muscles (III-16).
g
Grouping of muscle fiber types and frequent paracrystalline inclusions.