Table 2.
Results of laboratory investigations
| Family 1 (p.Y163X) | Family 2 (p.Y169X) | |||
|---|---|---|---|---|
| Proband 1 | Subject V‐1B | Proband 2 | Subject III‐5 | |
| Cardiovascular reflexes | – | |||
| HUTT (3rd min): | pathological | pathological | pathological | |
| ΔSBP, ΔDBP (mmHg); ΔHR (bpm) | −50, −30; 8 | −3, −17; – | −54, −38; −4 | |
| Valsalva ratio | 1.01 | – | 1.06 | |
| Overshoot (mmHg) | absent | 1.27 | absent | |
| Deep breathing: | absent arrhythmia | – | absent arrhythmia | |
| Cold Face (3rd min): | ||||
| ΔSBP, ΔDBP (mmHg); ΔHR (bpm) | 5, −4; −2 | – | 23, 15; −2 | |
| Electromyography | sensorimotor axonal PNP | normal | normal | sensorimotor axonal PNP |
| Skin sympathetic response | absent | absent | absent | absent |
| Cognitive dysfunction | mild global impairment (MMSE 23/30) with memory and visual attention dysfunction | globally normal (MMSE 30/30), but visuo‐spatial task impairment | globally normal (MMSE 26/30), but visual memory dysfunction | – |
| Electroencephalography | mild slowing | – | normal | – |
| Brain MRIa | nonspecific WM hyperintensities | normal | nonspecific WM hyperintensities | – |
| H1‐MRSa | normal | – | normal | – |
| Skin innervation analysis | autonomic SFN | autonomic and somatic SFN | autonomic and somatic SFN | – |
| Skin PrP immunostaining | positive | – | negative | – |
| Cerebrospinal fluid analysis | – | – | – | |
| Total proteins (mg/dL) | 215 | |||
| 14.3.3 protein assay | positive | |||
| Total tau protein (pg/mL) | 17,900 | |||
| Nf‐L (pg/mL) | 10,200 | |||
| Prion RT‐QuIC | negative | |||
a
Performed at the age of 66 in proband 1 and at the age of 60 in proband 2. – , Not done. [HUTT, head‐up tilt test; SBP, systolic blood pressure; DBP, diastolic blood pressure; HR, heart rate (bpm, beats per minute); PNP, polyneuropathy; MMSE, Mini Mental State Examinantion (normal value >24); WM, white matter; SFN, small fiber neuropathy; H1‐MRS, brain single voxel proton magnetic resonance spectroscopy (thalamus and cerebellum were analyzed in proband 1, parietal and occipital white matter in proband 2); Nf‐L, neurofilament light chain protein; prion RT‐QuIC, detection of prion seeding activity using real‐time quaking induced conversion assay].