Analysis of Neuromyelitis Optica Spectrum Disorder in an Indian Cohort using International Consensus Diagnostic Criteria.

Context: Updates on clinical, investigatory, and therapeutic aspects of neuromyelitis optica (NMO) spectrum disorders are rapidly evolving. Recently published international consensus diagnostic criteria (ICDC) allowed clinicians to rapidly diagnose the expanding spectrum of NMO spectrum disorders more accurately. Aims: The aim of the study was to retrospectively analyze 36 consecutive cases of comprehensively evaluated NMO spectrum disorders using the ICDC. Patients and Methods: We retrospectively collected 36 cases of NMO spectrum disorders who attended our unit between August 2012 andOctober 2016 and fulfilled the ICDC. All patients underwent magnetic resonance imaging (MRI) of the brain and whole spine with contrast, anti-aquaporin 4 antibody, and detailed blood investigations to rule out systemic vasculitis and other alternate diagnoses. Results: Female-to-male ratio was 6.2:1; 50% of the cases were in the 20-40-year age group. Six patients (16.67%) had combined optic neuritis and myelitis.Nine patients (25%) had pure longitudinally extending transverse myelitis LETM with positive anti aquaporin 4 antibody AQ4Ab. Fourteen patients (38.9%) had myelitis and optic neuritis separately. Nine patients (25%) had area postrema syndrome. Two patients (5.6%) had acute brainstem syndrome and one (2.8%) had hypothalamic syndrome. LETM was commonly found in the cervical level (69.4%).Four patients (11.1%) had no spinal cord involvement. Anti-aquaporin 4 antibody was positive only in 23 cases (63.9%). Conclusions: Initial presentation of NMO spectrum disorder is often due to brain lesions. The ICDC criteria have enhanced clinician's ability to diagnose NMO spectrum disorder in the early stages. In our study, ICDC criteria helped us to diagnose 33% additional cases that would have been missed if the old 2006 revised criteria was applied.

Mercury Toxicity Following Unauthorized Siddha Medicine Intake - A Mimicker of Acquired Neuromyotonia - Report of 32 Cases.

CONTEXT: Mercury is used extensively in the preparation of Siddha medicines, after purification. In this study, we present 32 patients of mercury toxicity following unauthorized Siddha medicine intake who mimicked neuromyotonia clinically. We analyzed the clinical features of these patients, the role of autoimmunity in etiopathology, and compared it with acquired neuromyotonia. SUBJECTS AND METHODS: This is a retrospective study to analyze inpatients in a tertiary care center, admitted with mercury toxicity following Siddha medicine intake from August 2012 to October 2016. We analyzed the clinical features, laboratory data including mercury, arsenic and lead levels in blood, and serum voltage-gated potassium channels (VGKC)-CASPR2 Ab in selected patients. RESULTS: Thirty-two patients who had high blood mercury levels following Siddha medicine intake were included in the study. All patients (100%) had severe intractable neuropathic pain predominantly involving lower limbs. Twenty-six (81.25%) patients had fasciculations and myokymia. Fifteen patients (46.86%) had autonomic dysfunction (postural hypotension and resting tachycardia). Nine (28.12%) patients had encephalopathic features such as dullness, apathy, drowsiness, or delirium. Anti-VGKC Ab was positive in 12 patients with myokymia. All the patients in the study consumed Siddha medicines obtained from unauthorized dealers. CONCLUSIONS: Mercury toxicity following Siddha medicine intake closely mimics acquired neuromyotonia; severe intolerable neuropathic pain is the hallmark feature; Positive VGKC-CASPR2 antibody in some patients must be due to triggered autoimmunity secondary to mercury toxicity due to Siddha medicine intake. The government should establish licensing system to prevent distribution of unauthorized Siddha medicines.

Tenofovir induced Fanconi syndrome: A rare cause of hypokalemic paralysis.

We report a 55-year-old female who presented to the emergency department with acute onset quadriparesis. She was diagnosed to have acquired immunodeficiency syndrome 7 years ago and was on tenofovir based anti-retroviral therapy for past 10 months. As the patient also had hypophosphatemia, glucosuria and proteinuria Fanconi syndrome (FS) was suspected. She improved dramatically over next 12 h to regain normal power and also her renal functions improved over next few days. Tenofovir induced FS presenting as hypokalemic paralysis is very rare complication and is the first case reported from India.

An interesting case of Leigh-like syndrome.

A 12-year-old female child with motor developmental delay presented with persistent vomiting, recurrent falls and unsteadiness in dark since 2 years of age. There was decline in scholastic performance, bulbar symptoms and aggravation of symptoms during intercurrent illness. Clinically, she had frontal and parietal lobar dysfunction, dysarthria, optic atrophy and LMN VII, IX, X, XII cranial nerve involvement. There was generalized hypotonia, distal muscle wasting, weakness, cerebellar signs and impaired vibration/position sense in distal extremities. Biochemical investigations revealed elevated serum/cerebrospinal fluid (CSF) lactate and CSF lactate pyruvate ratio. Neuroimaging demonstrated bilateral symmetrical T2 hyperintensities in basal ganglia, subcortical white matter, cerebellar hemispheres and posterior aspect of spinal cord. As certain atypical features like bilateral symmetrical T2 hyperintensities in subcortical white matter were also seen, metachromatic leukodystrophy was considered in differential diagnosis but ruled out by nerve biopsy. This case is reported for the presence of atypical neuroimaging features that are rarely found in Leigh's disease.