GRANULOMA CAUSED BY CHEMICAL AGENTS

Abstract

The author reviews granulomas caused by chemical agents. Since there is insufficient knowledge with which to classify them fundamentally, they are classified practically as inflammation caused by endogenous and exogenous chemicals. Deposits of urate crystals, cutaneous calcinosis and cholesterin granulomas are endogenous. Exogenous inflammations in human medicine are the occupational diseases of the skin and lungs; however, these are of little significance in domestic animals. Pneumoconioses in animals are rare because of their reduced opportunity for exposure, more efficient nasal filtering system, and increased pulmonary reactivity; the latter is more likely to lead to acute pneumonia than to chronic granulomatous response. Granulomas caused by pharmaceutical agents are of importance in animals, e.g. the cutaneous granuloma caused by aluminum hydroxide in the adjuvant of foot and mouth disease vaccine. Drugs suspended in oil, turpentine, and paraffin have also produced granulomas in the subcutaneous tissue and muscles. Peritoneal inflammation occurs as a reaction to talcum or antibiotic powder following surgery and is of importance in human medicine; cases have also been reported in domestic animals, but much more rarely. Granulomas were experimentally produced with talcum powder in a number of laboratory and domestic animals, reptiles and amphibia. Such experiments provide an approach to the study of the comparative pathology of inflammation. The differences in the reactions of nine species of animals with experimental talcum granulomas are tabulated.