Facilities, selection, outcome measurement, and limitations of therapeutic plasma exchange for neuroimmunological disorders: The South East Asian survey study.

INTRODUCTION: Therapeutic plasma exchange (TPE) for neuroimmunological disorders has played an important role in the Southeast Asian region. This study investigates the challenges of performing TPE within the region. METHOD: A questionnaire-based survey was conducted and launched to 15 South East Asian Therapeutic Plasma Exchange Consortium (SEATPEC) members from seven countries in January 2021. It included demographics, TPE techniques, indications, challenges, timing, outcome measurement, and access to laboratory testing in each local center. RESULTS: A total of 15 neurologists from 12 participating centers were included. They usually perform five sessions of TPE (100.0%), with 1 to 1.5 plasma volume (93.3%), and exchanges via the central catheter (100.0%). Acute relapses of neuromyelitis optica spectrum disorder and myasthenia gravis are the most common indications. They used a combination of normal saline and 5% albumin (60.0%) as replacement fluid. Most (66.7%) used TPE as an add-on treatment in steroid-refractory cases or as first-line treatment for severe attacks. They suggested assessing the TPE efficacy of TPE by the interval to the next attack, post-TPE relapse rates, and TPE-related complications. The major challenges within our region are expense, reimbursibility, and access to TPE. CONCLUSION: Although countrywise differences exist, all share similarities regarding methods, indications, timing, obstacles, and challenges of TPE for neuroimmunological conditions. Regional collaboration will be essential to identify strategies to reduce these barriers to access to TPE in the future.

Temporal dispersion in demyelination of POEMS syndrome and Castleman disease.

OBJECTIVE: We detailed the electrophysiological patterns of peripheral nerve temporal dispersion across spectrum of POEMS syndrome and Castleman disease (CD). METHODS: Compound muscle action potentials (CMAP) duration of 3 patients with POEMS syndrome and 2 with hyaline vascular type CD without clonal plasma cell dyscrasia were retrospectively analysed. RESULTS: Median and ulnar nerves distal CMAP duration were prolonged in all patients irrespective of plasma cell dyscrasia or M protein. All lower limbs distal CMAP responses were absent. Greatest distal CMAP duration prolongation was observed in median nerves for POEMS syndrome (17.0 ms, 158% upper limit normal) and in ulnar nerves for CD (9.8 ms, 47% upper limit normal). Distal/proximal CMAP duration ratio of <0.7 were seen in 33% of median and ulnar nerves studied among POEMS syndrome. Among nerves with ratio >0.7, all had distal CMAP duration prolongation (Range 7%-158% of upper limit normal). CONCLUSIONS: Abnormal distal CMAP dispersion is not uncommon in POEMS syndrome and CD without clonal plasma cell dyscrasia or M protein. POEMS syndrome has greater distal CMAP duration in median and ulnar nerves, particularly in median nerve that can reach up to 150% of upper limit normal, compared to <50% in CD. SIGNIFICANCE: Detailed electrophysiological analysis of distal CMAP duration may help in distinguishing POEMS syndrome and CD.

Anti-NMDAR Encephalitis in Association with Herpes Simplex Virus and Viral and Bacterial Zoonoses.

Multiple co-infections can predispose a patient to autoimmune encephalitis. Out of thirty cases of N-methyl-D-aspartate receptor (NMDAR) encephalitis seen at a single tertiary referral center, only two cases of co-infection with NMDAR encephalitis were identified. One of these cases was highly interesting due to the presence of more than one co-infections along with the presence of cortical dysfunction, seizures, and orofacial dyskinesias at the onset in a male in the absence of tumors, which was refractory to initial treatment.

Malignancy in Guillain-Barré syndrome: A twelve-year single-center study.

The relationship between Guillain-Barré syndrome (GBS) and malignancy is uncertain. We retrospectively analyzed data of 118 consecutive patients admitted with GBS from Birmingham, U.K. (2001-2012). We calculated relative cancer risk using different definitions and determined characteristics of malignancy-associated GBS. Malignancy was globally commoner in our GBS cohort compared to the general population (odds ratio: 2.08; CI: 1.06-3.71; p=0.036). However, this was unconfirmed if paraneoplastic criteria were applied. GBS patients with cancer were significantly more likely to be older (p=0.043), hyponatremic (p=0.037) and demonstrate more axonal loss (p<0.05). Cerebrospinal fluid (CSF) protein levels were lower in the malignancy group (p=0.002) and neurological improvement less likely (p=0.023). In-patient mortality was significantly higher in patients with malignancy (p<0.01). We conclude global cancer risk is higher in GBS than in the general population, although definition-dependent. Malignancy requires consideration in elderly, hyponatremic subjects with normal CSF protein, severe axonal loss, who fail to improve post-treatment.