 This trial will test the hypothesis that among 90 children and adolescents with Crohns disease, ulcerative colitis, systemic-onset juvenile rheumatoid arthritis, juvenile dermatomyositis, systemic lupus erythematosus, mixed connective tissue disease and vasculitis, treatment of glucocorticoid-associated osteopenia and osteoporosis with 18 months of alendronate FOSAMAX, Merck Co., Inc. will result in greater improvement in the mean change of individual AP spine bone mineral density BMD gmcm2 determined by dual energy X-ray absorptiometry DXA than treatment with 18 months of standard of care therapy. 