Nerve cross-sectional area in advanced uremic neuropathy: A nerve ultrasound pilot study

BACKGROUND AND PURPOSE

Uremic neuropathy (UN) is a disabling neuropathy in end-stage kidney disease (ESKD) affecting the majority of patients receiving long-term hemodialysis (HD). One previous nerve ultrasound study reported an increased cross-sectional area (CSA) of the median nerve in moderate UN, while another study found enlarged sural nerves in small-fiber polyneuropathy associated with ESKD. The present cohort study aims to analyze bilateral CSA of multiple nerves in UN.

METHODS

Ten nondiabetic ESKD patients with UN on HD for at least 2 years and 10 healthy age-matched controls underwent bilateral ultrasound examinations with CSA measurements in 13 arm and leg nerve sites. Nerve conduction studies (NCS) and the total neuropathy score (TNS) were recorded. Pearson's coefficient and the Mann-Whitney U-test were used to analyze correlations and compare groups.

RESULTS

ESKD patients presented advanced neuropathic symptoms (mean TNS 15.9). NCS showed significantly reduced motor and sensory amplitudes in the UN group compared to the control group, and a slightly reduced nerve CSA was observed in 5 of 13 nerve sites (p < .05); the other nerve sites were not enlarged. Sural nerve CSA (p < .05) and sensory amplitude (p < .01) were negatively correlated with the TNS.

CONCLUSIONS

Nerve enlargement was not observed in the present study in advanced UN. A reduced nerve CSA observed in the sural nerve suggests an axonal loss associated with long-term HD in ESKD. During clinical workup of an acute disease of the peripheral nervous system in ESKD patients, nerve enlargement might be attributable to other causes than chronic UN.

Accelerated neuropathy among chronic kidney disease patients undergoing hemodialysis: Analysis of an institutional cluster

BACKGROUND

Accelerated neuropathy is a rare syndrome of rapidly worsening peripheral neuropathy, typically described in end-stage kidney disease (ESKD) patients undergoing dialysis. In our center, we encountered a surge in the occurrence of accelerated neuropathy among ESKD patients undergoing hemodialysis, which prompted systematic research.

METHODS

In this case-control study, we present the clinical features, electrophysiologic findings, and outcome of a series of patients who developed accelerated neuropathy after commencing hemodialysis for ESKD. Those who initiated hemodialysis and did not develop accelerated neuropathy were included as controls. We used logistic regression to identify predictors of accelerated neuropathy.

RESULTS

Among 436 ESKD patients who initiated hemodialysis over 4 years, 17 were diagnosed with accelerated neuropathy. The median-time (interquartile range) from hemodialysis initiation to presentation with accelerated neuropathy was 3 weeks (2-6). It typically presented as acute onset of unsteadiness of gait necessitating assistance for ambulation. Electrophysiology revealed length-dependent symmetric sensorimotor axonal neuropathy. Diabetes mellitus (odds ratio [OR] 4.1, 95% CI 1.2-13.9, p = 0.02), pre-existing peripheral neuropathy (OR 9.25, 95% CI 2.79-30.6, p < 0.001), and serum alkaline phosphatase (OR 1.2 for every 10 U increase, 95% CI 1.00-1.52, p = 0.04) significantly predicted accelerated neuropathy. With continued dialysis and supportive care, neurologic status improved, total-neuropathy score (summary score of peripheral nerve dysfunction incorporating clinical and electrophysiological parameters) declined from 26.5 to 18.4 (p < 0.001) and most regained unassisted ambulation.

CONCLUSION

This study presents the largest series of patients with accelerated neuropathy and has identified predictors. However, in view of the unusually high incidence of accelerated neuropathy we speculate that other unidentified factor(s) could be underlying its pathogenesis.

High-resolution nerve ultrasound and corneal confocal microscopy in taxane-induced polyneuropathy

BACKGROUND AND PURPOSE

The role of high-resolution nerve ultrasound (HRUS) and corneal confocal microscopy (CCM) in the early detection of taxane-induced polyneuropathy (TIPN) is unclear. The present prospective longitudinal controlled observational pilot study estimates the role of HRUS and CCM in the early diagnosis of TIPN in breast cancer patients.

METHODS

Fifteen breast cancer patients receiving paclitaxel and 15 healthy age matched controls were included. Visits before and 3 weeks, 8 weeks and 6 months after treatment included clinical examination, the total neuropathy score, nerve conduction studies (NCS), monocular CCM including corneal nerve fibre length, density and branching and HRUS of bilateral median, ulnar, radial, tibial, peroneal and sural nerves. Patients were compared between different visits and to healthy controls.

RESULTS

Total neuropathy score increased from 2.2 at baseline to 5.8 (p < 0.001) at week 8. NCS showed a decreased sensory amplitude in the sural, radial, ulnar and median nerve after 6 months (p < 0.001). HRUS revealed a significant increase of cross-sectional area in the sural nerve (p = 0.004), the median nerve (p = 0.003) at the carpal tunnel and the ulnar nerve in the forearm (p = 0.006) after 6 months. CCM showed no changes at different visits.

CONCLUSIONS

Corneal confocal microscopy and HRUS do not detect early signs of TIPN during the paclitaxel treatment period. HRUS and NCS might detect congruent signs of an axonal, predominantly sensory polyneuropathy after 6 months. The clinical examination remains the most sensitive tool in the early detection of TIPN in breast cancer patients.

Comparing neuropathy in multiple myeloma and AL amyloidosis

Peripheral neuropathy (PN) is frequent in patients with monoclonal gammopathy due to plasma cell dyscrasia, but little is known about the comparative impact of nerve dysfunction in different disorders. We compared clinical and laboratory results between two diagnostic groups. We recruited 76 untreated multiple myeloma (MM) and 27 AL amyloidosis (ALA) patients for evaluation of symptoms, clinical findings and nerve conduction studies (NCS). We diagnosed significant PN using total neuropathy scores (TNS > 7) in 17.6% of MM and 48.1% of ALA patients and in 27.7% of MM and 35.7% of ALA patients using NCS findings. TNS score grades were significantly higher in the AL amyloidosis patients (Fisher's exact test: P = .02) but a NCS based PN diagnosis was not significantly different (Fisher's exact test: P = .13). A significantly higher TNS vibration (P = .04) and pin (P = .02) sensory sign and TNS reflex (P = .04) sign score was found in amyloidosis patients. Likewise, quantitative sensory thresholds for vibration was higher in amyloidosis patients (Welsh ANOVA: P = .01). NCS revealed signs of more frequent axonal tibial neuropathy with significantly lower motor response amplitudes (P = .02) and resulting higher TNS scores (P = .002), while sural nerve sensory response amplitudes were without significant difference (P = .86). We found more severe TNS grades of PN in AL amyloidosis patients compared with MM patients. We also found higher sensory symptoms scores and higher thresholds for vibration but similar sensory involvement using NCS. The NCS exclusively showed signs of an axonal neuropathy.

Effect Evaluation of Strychnos nux-vomica L. with Integrative Methods for Bortezomib-Induced Peripheral Neuropathy in Multiple Myeloma Patients: A Self-Controlled Clinical Trial

OBJECTIVE

To explore the clinical effect and adverse reactions of Strychnos nux-vomica in bortezomib-induced peripheral neuropathy (BIPN) of patients with multiple myeloma (MM).

METHODS

A total of 19 MM patients with BIPN were enrolled and Nux Vomica Capsule (NVC, 0.4 g, thrice daily) were orally administrated for 30 days. Comparative analysis on parameters between pre- and post-therapy, including peripheral neuropathy (PN) grade, neurotoxicity score, Chinese medicine (CM) syndrome score, total neuropathy score (TNS), coagulation function, and serum nerve growth factor (NGF) levels were conducted. The adverse events were monitored.

RESULTS

In BIPN of MM patients who received NVC, PN grade was lowered, neurotoxicity score was obviously decreased (P⩽0.01), and both CM syndrome score and TNS were remarkably decreased (P<0.01). After the therapy, activated partial thromboplastin time was prolonged (P<0.01) and fibrinogen was declined (P<0.05), showing improvement in the hypercoagulable state of patients. No significant difference of NGF recovery degrees was detected between pre- and post-therapy (P>0.05). No evident adverse reactions were observed during the course of treatment.

CONCLUSION

Strychnos nux-vomica L. has significantly effect with a good safety in treatment of BIPN in MM patients.

Vincristine-induced neuropathy in childhood ALL (acute lymphoblastic leukemia) survivors: prevalence and electrophysiological characteristics

The prevalence and the burden of vincristine-induced neuropathy have been poorly documented in childhood acute lymphoblastic leukemia survivors. This cross-sectional study was carried out at a tertiary care center in northern India from October 2011 to June 2012. Eighty consecutive acute lymphoblastic leukemia survivors aged 5 to 18 years, within 3 years of completion of their chemotherapy, were enrolled. After clinical evaluation, detailed nerve conduction studies were performed and the reduced version of the Total Neuropathy Score was calculated. The mean age at the time of evaluation was 11.2 ± 3.2 years. 33.75% had neuropathy electrophysiologically. Symmetric motor axonal polyneuropathy was the most common pattern of involvement seen in 19 (23.8%) children. There was significant improvement with time, as revealed by lower prevalence of neuropathy with increasing interval following vincristine injection. 33.75% of the children had Reduced version of Total Neuropathy Score ≥ 1.

Characteristics of bortezomib- and thalidomide-induced peripheral neuropathy

Dose-limiting peripheral neuropathy (PN) is frequently reported with the use of thalidomide and bortezomib, novel proteasome inhibitors. While these two agents have significant activity in multiple myeloma (MM), the combination and the associated PN have not been fully examined in untreated patients. The objective of this study was to report the baseline prevalence and occurrence of PN in newly diagnosed MM patients treated with bortezomib and thalidomide. Twenty-seven patients (11 men and 16 women) with previously untreated MM were prospectively monitored for PN. Total neuropathy score reduced (TNSr) was calculated at baseline and after every two cycles of bortezomib treatment. The median cumulative dose of bortezomib was 35.6 mg/m(2) (median 8 cycles) and of thalidomide was 16.8 g. Only three subjects showed mild PN at baseline (whole group median TNSr 0). At the end of treatment, PN developed in 26 patients (median TNSr 8). PN was of mild to moderate severity (TNSr grade 1 = 11, grade 2 = 10, grade 3 = 5, and grade 4 = 0). Nerve conduction studies showed axonal physiology in all except three subjects in whom demyelinating physiology was noted. The median TNSr was 17 in the demyelinating group and 9 in the axonal group. There was no significant correlation of TNSr with cumulative bortezomib or thalidomide dose. At follow-up, 80% of patients had become asymptomatic after discontinuation of the chemotherapy. We conclude that bortezomib and thalidomide combination chemotherapy induces a reversible length-dependent sensory>motor, predominantly axonal, large-fiber>small-fiber polyneuropathy. In a subset, a more severe demyelinating polyneuropathy may develop.