Mean age of presentation and follow up are 38 yrs and 15 months respectively. MMT-8 at baseline(54) ,MMT-8 6m (69) ,final follow up (74).Dermatomyositis(DM) and overlap myositis (OM) were 37% each , necrotising myositis (NAM)19% and anti-synthetase syndrome (ASS)7% . Positive ANA (39%), myositis specific antibody 66% and myositis associated antibody 58% ,paraneoplastic antibody 6.5%.Pelvis and adductors muscle MRI showed fatty replacement in 83.6% (41/49) , edema 85%(42/49) .Anterior thigh FR-81.6%  ,edema 85.7% ,Posterior thigh FR-89.7% and edema 81.6% .Ant distal lower limb FR-63.2%  and edema -69.3% .In PDLL 67.3% FR and edema 63.2% . ILD was observed in 13%.FDG uptake also showed good correlation with histopathological features & muscle oedema in MRI.SUV mean ,SUV max ratio were higher among non responders. Muscle biopsy 36% cases showed muscle necrosis(28%)  perimysial infiltrates(20%) ,endomysial infiltrates(22%) ,perifasicular atrophy(11%) &fibrosis(23%).Outcomes showed best treatment responders(36%) , satisfactory responders(39%) ,unsatisfactory responders(13%) and non responders (11%).Non responders had higher ICU admissions=30.4%(7)(p<0.01),endotracheal intubations=13%(p<0.01), infections=39.1%(18), multiple immunomodulatory agents, severe weakness and rapidly progressive weakness=87%(n=20, p<0.01), chronic continuous course 82.6%(n=19, p=0.01) and higher number of relapses(p< 0.05).Multivariate logistic regression showed that lower score of  MMT-8 at baseline (p<0.01) and higher number of relapses (p<0.05) were independent predictors of non-response. These parameters could predict non-response with a sensitivity of 30.4% and specificity of 91.2% with area under the curve (ROC-0.775)