Chinese Medical Journal

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RECENT ADVANCES IN DIAGNOSIS OF PARAGONIMIASIS a

patient with a positive history of having eaten raw crabs or raw crayfish, particularly when the crustacea consumed were from endemic regions, should be considered as a potential case of paragonimiasis until proved to the contrary.

2. Diagnostic importance of intradermal test for paragonimiasis.. In our experience(7,8) cases of paragonimiasis have invariably shown a strongly positive reaction to an intradermal injection with paragonimus antigen Recently the intradermal test was used by us for screening paragonimiasis cases during surveys in endemic as well as in suspected areas. In one locality where 2,309 individuals were examined, 398 (17.2 per cent) were found to have paragonimiasis as evidenced by the positive intradermal test. Of these 398 patients with positive reaction, however, only 117 revealed ova in the sputum upon the first examination. Complement fixation tests of the sera collected at random from a group of these patients with positive intradermal reaction but with no ova in the sputum were done and they all showed a clear-cut positive complement fixation reaction. The disparity between the number of skin-test positive cases and that of sputum-positive cases, however, dwindled very rapidly in direct proportion to the number of examinations of sputum specimens collected at different times from the same patients, because most of the cases with positive skin-test but with negative sputum on the first examination eventually showed ova in the sputum when repeated examinations were made. Some of the patients actually had no sputum, and the so-called sputum specimens examined were saliva mixed with mere pharyngeal secretions. In such cases it was only natural that no ova could be found. It seems very clear that intradermal test with paragonimus antigen is a most valuable procedure for the diagnosis of paragonimiasis in clinical practice as well as in epidemiological surveys. According to our recent experience in Kwangtung province skin tests done with antigens made from adult worms of Schistosoma japonicum and Clonorchis sinensis separately were quite specific and useful.

3. Diagnostic importance of complement fixation test of serum and spinal fluid for paragonimiasis. We found that out of 51 inpatients with proved paragonimiasis whose sera were subjected to the complement fixation test, 50 cases or 98 per cent showed a clear-cut positive reaction and only 1 case or 2 per cent gave a negative result. The cerebrospinal fluids of 24 inpatients with cerebral paragonimiasis were also subjected to the same test, and 20 cases or 83 per cent showed a positive reaction and 4 cases or 17 per cent reacted negatively. On the other hand, the cerebrospinal fluids of paragonimiasis patients without cerebral involvement all gave a negative complement fixation reaction. It should be pointed out here that although the sera of some of the patients with clonorchiasis or leprosy also showed a positive complement fixation reaction, cerebrospinal fluids of these cases never gave a cross positive or a false positive reaction