The prevalence and clinical phenotype of dual seropositive neuromyelitis optica spectrum disorders at a national reference center in South Asia.

BACKGROUND: Neuromyelitis Optica Spectrum Disorders (NMOSD) is an autoimmune syndrome that is frequently positive for Aquaporin 4 (AQP4) IgG or Myelin Oligodendrocyte Glycoproteins (MOG) IgG. However, dual positivity to both is rare. OBJECTIVE: To assess the prevalence of dual-positive NMOSD and outline its clinical phenotype. DESIGN/METHODS: This is a retrospective cross-sectional study conducted at a tertiary healthcare center in South Asia between August 2018 and November 2021. The serum and/or CSF samples of suspected cases of NMOSD were tested for both AQP4-IgG and MOG-IgG using an Indirect immunofluorescence test on transfected cells. RESULTS: During the study period, 1935 cases of NMOSD were tested for both antibodies- 65 patients (3.35%; 57 females and 8 males) tested positive for AQP4-IgG, 217 patients (11.21%; 122 females and 95 males) tested positive for MOG-IgG and 3 patients (0.15%; 2 females and 1 male) showed dual positivity. There was a strong female preponderance in all three groups (87.69%, 56.22%, and 66.66% respectively). This study identified 3 patients with dual positivity. The first patient (42 years, Male) presented with area postrema syndrome initially and subsequently relapsed by developing right-sided numbness of the temporal area and limbs during which he tested dual positive. The second patient (27 years, Female) presented with bilateral optic neuritis (left>right) initially and subsequently relapsed following an episode of a seizure with left-sided hemiplegia. The third patient (25 years, Female) initially presented with acute bilateral optic neuritis and later developed left-sided hemiplegia post-recovery at which point she tested dual positive. Management using methylprednisolone was ineffective for all three patients, however, plasmapheresis and/or periodic rituximab injections produced an excellent response. CONCLUSIONS: Our study reports that the prevalence of dual-positive NMOSD is 0.15% and its clinical phenotype is more similar to NMO rather than MOG- associated disease.

Prozone phenomenon observed in indirect immunofluorescence assay by antibodies against neuronal antigens.

A marked prozone effect was observed in indirect immunofluorescence with human sera and human cerebrospinal fluid in two clinical cases involving breast carcinoma with paraneoplastic neuronal antibodies, and anti- N-methyl-D-aspartic acid (NMDA) receptor antibodies. Anti-Yo antibodies and anti-NMDA antibodies were not detectable under high concentrations (1:10 serum dilution and neat CSF respectively) but showed a true effect when sufficiently diluted at 1:80 and 1:5 respectively. This paper demonstrates that prozone effects have their occurrences in indirect immunofluorescence, and clinicians and laboratory technicians should be wary of its implications during screening of autoantibody markers in neurological diseases.

Endoscopic therapy for biliary strictures complicating living donor liver transplantation: Factors predicting better outcome.

AIM: To identify factors predicting outcome of endoscopic therapy in bile duct strictures (BDS) post living donor liver transplantation (LDLT). METHODS: Patients referred with BDS post LDLT, were retrospectively studied. Patient demographics, symptoms (Pruritus, Jaundice, cholangitis), intra-op variables (cold ischemia time, blood transfusions, number of ducts used, etc.), peri-op complications [hepatic artery thrombosis (HAT), bile leak, infections], stricture morphology (length, donor and recipient duct diameters) and relevant laboratory data both pre- and post-endotherapy were studied. Favourable response to endotherapy was defined as symptomatic relief with > 80% reduction in total bilirubin/serum gamma glutamyl transferase. Statistical analysis was performed using SPSS 20.0. RESULTS: Forty-one patients were included (age: 8-63 years). All had right lobe LDLT with duct-to-duct anastomosis. Twenty patients (48.7%) had favourable response to endotherapy. Patients with single duct anastomosis, aggressive stent therapy (multiple endoscopic retrograde cholagiography, upsizing of stents, dilatation and longer duration of stents) and an initial favourable response to endotherapy were independent predictors of good outcome (P < 0.05). Older donor age, HAT, multiple ductal anastomosis and persistent bile leak (> 4 wk post LT) were found to be significant predictors of poor response on multivariate analysis (P < 0.05). CONCLUSION: Endoscopic therapy with aggressive stent therapy especially in patients with single duct-to-duct anastomosis was associated with a better outcome. Multiple ductal anastomosis, older donor age, shorter duration of stent therapy, early bile leak and HAT were predictors of poor outcome with endotherapy in these patients.

Time trends in the etiology of chronic pancreatitis in South India.

BACKGROUND: Recent reports indicate a decline in prevalence of classical tropical chronic pancreatitis (TCP). We studied the etiologies and risk factors over a 14-year period at a tertiary care university hospital. METHODS: We compared the etiology in chronic pancreatitis (CP) patients presenting and followed-up in our Pancreas Clinic over two time periods (2000-06 and 2007-13). RESULTS: Idiopathic chronic pancreatitis (ICP) was the predominant etiology seen over the two time periods. However an increase in prevalence of alcoholic chronic pancreatitis (ACP) during the latter time period suggests that it may be emerging as a dominant etiology over recent years. Hypertriglyceridemia and hyperparathyroidism were uncommon causes of non-alcoholic CP. Autoimmune pancreatitis was noted only during 2007-13, but remains a rare cause of CP. There are multiple risk factors for CP in our population. CONCLUSIONS: The high prevalence of ICP indicates need closer examination of risk factors and ICP pathogenesis. ACP appears to be emerging as a dominant cause of CP which suggests a need to reorient preventive strategies.