Article Text
Abstract
Single lots of a Chase-Siltzbach type I Kveim test material from each of two sarcoid spleens and designated lot 5 of spleen K12 and lot 1 of spleen K13 have been validated alongside a single lot (lot 10) of a 'standard' suspension provided by Dr L. E. Siltzbach and prepared identically from the spleen of patient J (SPLEEN J) in New York. Additionally, a half-dilution of lot 5, K12, was included in this comparison. The reactivity of each suspension was assessed among patients with active and inactive sarcoidosis. The selectivity of each suspension for sarcoidosis was assessed similarly by comparison with results in patients with active and quiescent pulmonary parenchymal tuberculosis and in healthy subjects. All patients were closely matched and two Kveim tests were made in each subject according to a prearranged statistical design. The reactivity of the K12, K12 1/2 dilution, and K13 suspensions among patients with active and inactive sarcoidosis was closely similar to that with the 'standard' S10 suspension and in accordance with the expected proportions of reactions in patients at different stages of sarcoidosis. The K12, K13, and 'standard' S10 suspensions yielded a negligible proportion of positive reactions among patients with active and quiescent pulmonary tuberculosis and among healthy subjects: thus, as judged by these tests each suspension showed a high degree of selectivity for sarcoidosis. The results of this validation study are discussed in relation to the results of other studies in which lots 5 and 14 of K12 and early and late batches of a suspension prepared from another sarcoid spleen at the Commonwealth Serum Laboratories designated CSL and provided by Dr T.H. Hurley in Melbourne were employed. Using lot 5 of K12 positive reactions were found in an appreciable proportion of patients with Crohn's disease, ulcerative colitis, and tuberculous lymphadenitis. A closely similar rate of positive reactions was encountered among patients with Crohn's disease following tests with batch 0025 of CSL suspension and with another lot (lot 14) derived from spleen K12. A close concordance of results was obtained with lot 5(K12) and with batch 0042 CSL among patients with ulcerative colitis, but at a lower rate of reactivity. We conclude that positive reactions also occur in some diseases other than sarcoidosis and consider that the difficulties in determining the criteria for an acceptable test suspension become increasingly apparent as additional Kveim tests are made with one particular lot and with seqential lots of material from a 'validated' tissue source.