CISP-Plus: Expanding the Spectrum of Chronic Immune Sensory Polyradiculopathy (CISP)

Objectives:Sensory loss with normal nerve conduction studies (NCS) from focal sensory root inflammatory demyelination is characteristic of chronic immune sensory polyradiculopathy (CISP). However, non-pure cases involving motor and distal sensory nerves exist (CISP-plus). We hypothesize that CISP-plus and CISP are fundamentally part of the same syndrome through comparison of clinical, neurophysiological and pathological features.Methods:CISP-plus (primary dorsal root with lesser motor and sensory nerve involvement) and CISP cases were retrospectively analyzed (1986-2019).Results:We identified 44 CISP-plus and 28 CISP cases (n=72) with 86% (38/44) of CISP-plus and 79% (22/28) of CISP patients experiencing imbalance. On examination, large fiber sensory loss was present in 98% (43/44) of CISP-plus and 96% (27/28) of CISP. Gait ataxia was evident in 93% (41/44) of CISP-plus and 79% (22/28) of CISP. Mild distal weakness was common in CISP-plus (75%, 33/44). NCS showed mild abnormalities in all CISP-plus and were normal (by definition) in all CISP. Elevated cerebral spinal fluid (CSF) protein, slowing of somatosensory evoked potentials and MRI root enhancement occurred in most CISP-plus and CISP cases. Eleven CISP-plus nerve biopsies showed loss of large myelinated fibers and onion-bulb formation most prominent in rootlet biopsies. Immunotherapy resulted in marked improvement of gait ataxia in 84% (27/32) of CISP-plus and 93% (14/15) of CISP cases with return to normal neurological examination in half (25/46).Conclusion:The recognition of CISP-plus expands the spectrum of CIDP by combining CISP-plus (predominant sensory polyradiculopathy with mild motor and sensory nerve involvement) with pure-CISP (focal sensory polyradiculopathy) together as proximal sensory CIDP.

Clinical and Pathological Variation of Charcot-Marie-Tooth 1A in a Large Chinese Cohort

Charcot-Marie-Tooth 1A (CMT1A) caused by peripheral myelin protein 22 (PMP22) gene duplication is the most common form of hereditary polyneuropathy. Twenty-four genetically confirmed CMT1A patients with sural nerve biopsies were enrolled in this study. The clinical picture included a great variability of phenotype with mean onset age of 22.2±14.5 years (1–55 years). Pathologically, we observed a severe reduction in myelinated fiber density showing three types of changes: pure onion bulb formation in 3 cases (12.5%), onion bulb formation with axonal sprouts in 10 cases (41.7%), and focally thickened myelin with onion bulb formation or/and axonal sprouts in 11 cases (45.8%). We observed no significant correlation between nerve fiber density and disease duration. There was no significant difference between the 3 pathological types in terms of clinical manifestations, nerve fiber density, and g-ratio. Our study indicates that there is marked variability in the age of onset of CMT1A, as well as significant pathological changes without deterioration with the development of the disease. Focally thickened myelin is another common morphological feature of demyelination.

Intraneural perineurioma of the third cranial nerve: occurrence and identification

✓Intraneural perineurioma is a true but rare neoplasm that originates from perineurial cells and mainly affects peripheral nerves. It must be distinguished from other hypertrophic neuropathies that are either inflammatory or demonstrate an onion-bulb formation that originates from Schwann cells. Complying with this strict definition, only three additional cases of cranium-related perineurioma have been identified: two lesions arose extracranially and involved cranial nerves, and one occurred intracranially but did not involve a nerve. The authors describe a 27-year-old woman who presented with left third cranial nerve palsy and was found to harbor a mass lesion in the superior orbital fissure and cavernous sinus. After subtotal resection had been performed, pathological studies confirmed the presence of perineurial tumor cells in a pseudo–onion bulb formation. The cells stained positively for epithelial membrane antigen but not for S100 protein, clearly distinguishing the disease from one that originates in Schwann cells.

338 Timing of Onion Bulb Formation under Field Conditions in New York in Relation to Temperature, Photoperiod, and Cultivar

Although it has been known since the 1930s that long photoperiods and high temperatures hasten bulb formation in onions, the time at which onion cultivars under field conditions in New York start forming bulbs has not been previously reported. In the 1997 and 1998, onion cultivars were seeded in three commercial onion production areas at normal early spring planting dates. In 1998, a time-of-planting study was carried out in Ithaca, N.Y., in which three transplanted crops and three direct-seeded crops were established at monthly intervals beginning at the end of March. Bulb ratios (bulb diameter: neck diameter) were measured at 2-week intervals during the season in all plantings. Initiation of bulbs (assumed to occur 3 weeks before bulb ratio reached 2) was then related to the photoperiod and air temperature up to that point. A comparison of early, mid-season, and late cultivars indicated that bulbs are initiated in commercial plantings in New York at close to the longest day of the year (15.6 h), at a time when mean temperature is still rising. In the time of planting study, delay of planting resulted in fewer days from emergence to bulb initiation and a reduction in growing degree-day accumulation. If planted later than 15 June, some cultivars failed to initiate bulbs, but others, such as `Quantum' and `Winner', initiated bulbs but did not mature them. The results indicate that photoperiod appears to be the primary factor for the initiation of bulbs, but that bulb initiation can be modified strongly in some cultivars by temperature.