Cora R. Owen

The Passive Cutaneous Anaphylaxis (PCA) Test in Adiaspiromycosis

Adiaspiromycosis is the name proposed by Emmons and Jellison (1960) to replace haplomycosis (Emmons, 1948) for infections with the fungal agents Emmonsia parva (Emmons & Ashburn, 1942) and Emmonsia crescens Emmons & Jellison (1960). Natural infections with these fungi are restricted to the lungs of a great variety of mammals (FIG. 1). Emmonsia is one of the few mycotic agents not reported in man but known to be present in a great variety of wild animals. Diagnosis in man would probably depend on post mortem microscopic examination, as the spherules, measuring 400-500 t, are too small for X-ray resolution, and, since they remain fixed in lung tissue, they are not present in sputum. However, small concretions, carbon, oil globules and other material are common in the human lung and a few spherules of this fungus could well escape notice. Because of the difficulties in etiologic diagnosis of infection, a diagnostic immunologic test seemed highly desirable. The passive cutaneous anaphylaxis (PCA) test in cavies has been described by Ovary (1958) and his colleagues (Ovary and Bier, 1953; Ovary and Briot, 1951) and this test has been adapted with some success to the study of adiaspiromycosis. The results of these studies and the discovery of 2 possible human infections are reported here.

Applicability of the Ascoli Test to Epizootic Tularemia in Wild Rodents

The Ascoli thermoprecipitin test for diagnosis of tularemia has been applied to experimentally infected animals including voles (Microtus) and found to be useful in identifying the infection (Larson, 1951). Sarchi (1930) reported successful use of the method for diagnosis of tularemia in water rats (Arvicola) in Russia, but no reports have appeared in this country on practical application of the test to diagnosis of disease in wild animals. A great increase in voles in several western states and the occurrence of tularemia among them (Jellison et al., 1958) afforded an opportunity for application of the test to field specimens.