Tyrophagus putrescentiae: an allergenically important mite.

The incidence of positive skin tests to the mite Tyrophagus putrescentiae was measured and compared with skin reactions to Dermatophagoides pteronyssinus and other allergens in Australian and New Guinean populations, and mite counts were determined in Sydney and New Guinea houses. Positive reactions to T. putrescentiae were as frequent as those for D. pteronyssinus in asthmatics in Sydney and were the commonest positive reactions in the normal New Guinea population. T. putrescentiae-specific serum IgE levels were determined and some IgG cross-reactions of D. pteronyssinus and T. putrescentiae antigens were demonstrated. It is suggested that T. putrescentiae is an important source of allergen and should be considered whenever D. pteronyssinus is thought to be a problem. A convenient method for culturing and isolating T. putrescentiae is described.