Interstitial Inflammation is almost the converse of that just mentioned. In it the inflammation affects chiefly the connective tissue, which forms the supporting stroma of organs. In acute inflammations there will be an infiltration of the connective tissue with leucocytes, and in some cases this may be so intense as to give rise to infiltration of pus. In chronic inflammations there will be new-formation of tissue, usually resulting in induration. A frequent consequence of chronic interstitial inflammation is atrophy of the proper parenchyma of the organ, produced by the shrinking of the connective tissue, but also partly by the action of the irritant on the parenchymatous structures.