Methods for treating a human patient for an inflammatory or autoimmune disease that is associated with CD40-expressing cells are provided, where the human patient is heterozygous or homozygous for FcγRIIIa-158F (genotype V/F or F/F). Also provided are methods of inhibiting antibody production by B cells in a human patient who is heterozygous or homozygous for FcγRIIIa-158F (genotype V/F or F/F). The methods comprise administering to the human patient a therapeutically or prophylactically effective amount of an anti-CD40 antibody. Methods and kits for identifying a human patient with an inflammatory or autoimmune disease that is treatable with an anti-CD40 antibody and which is non-responsive or refractory to treatment with rituximab (Rituxan®), as well as methods and kits for selecting an antibody therapy for treatment of a human patient having an inflammatory or autoimmune disease that is non-responsive or refractory to treatment with rituximab (Rituxan®), are also provided. The methods of the present invention find use in treatment of inflammatory diseases and autoimmune diseases that are associated with CD40-expressing cells. These methods are particularly advantageous with respect to inflammatory diseases and autoimmune diseases that are associated with cells expressing both CD40 and CD20, as the methods enable the treatment of patients having an inflammatory or autoimmune disease that is non-responsive or refractory to therapy with other therapeutic agents such as anti-CD20 antibodies.