Geoffrey Rake

Observations on the Toxicology of Sulfathiazole and Sulfapyridine

Summary If the sodium salts of the two drugs be used, the toxicity of sulfathiazole appears to be about 65% of the toxicity of sulfapyridine for LD50. Repeated administration of the drugs in the food of mice indicates that sulfathiazole is more toxic than sulfapyridine at a high dose level but that there is no difference at a dose level which is effective therapeutically. In monkeys and growing rats, receiving either drug for 14-57 days, sulfapyridine is clearly the more toxic. The principal pathological change in all 3 species appears to be renal damage. Metabolic studies indicate that sulfathiazole is more rapidly metabolized and undergoes much less conjugation than sulfapyridine.

Agent of Lymphogranuloma Venereum in the Yolk-Sac of the Developing Chick Embryo

In the course of chemotherapeutic studies, experiments were performed with a strain of the agent of lymphogranuloma venereum∗ in which passage-mouse brain was used as a source of virus. About one-third of all mice given intracerebrally 0.03 ml of 1:100 dilution died. The Ld50 1 was obtained with a dilution of 1:14. Because of its low mouse-virulence, which is in confirmation of the results of others, 2 , 3 an attempt was made to adapt the infective agent to the chorio-allantois of the chick embryo 4 in the hope of increased activity. Lesions appeared on this membrane, albeit irregularly. 5 Thus during 15 passages, approximately two-fifths of all eggs inoculated showed no lesions; one-fifth showed large central foci on the membrane; and in two-fifths the chorio-allantois showed few or many grey foci, 1 mm in diameter. The virus on the chorio-allantois was never lethal for the embryo. When 3rd, 4th and 5th passage membranes were tested in mice, 3 out of 4, 0 out of 4, and 1 out of 4 animals respectively died following intracerebral infection with 1:5 dilution. No mice succumbed when inoculated from the 10 subsequent passages. It appears, therefore, that during propagation in this tissue the particular strain of lymphogranuloma venereum virus either persisted there in very low titer or else suffered a further loss in its virulence for mice. In view of these conditions, a further effort was made to procure more active infection by recourse to inoculation into the yolk-sac, a method used by Cox 6 to obtain large numbers of rickettsiae. Passages were initiated with mouse-brain material. Five, 6- or 7-day eggs were injected in the yolk-sac with a volume of 0.5 to 1 ml of suspension.

Similarities and Possible Relationships Among Viruses of Psittacosis, Meningopneumonitis, and Lymphogranuloma Venereum

Findlay, Mackenzie and MacCallum 1 have described a developmental cycle for the virus of lymphogranuloma venereum in the brains of infected mice and have pointed out that the developmental forms present many analogies to those exhibited by the causal agent of psittacosis. 2 , 3 More recently Rake, Jones and Shaffer 4 have studied the developmental cycle of the virus of lymphogranuloma venereum in the yolk-sac cells of the developing chicken embryo and have pointed out the quite amazing similarity in morphology and staining reaction between the respective developmental forms in the two viruses. The viruses of lymphogranuloma venereum, psittacosis, meningopneumonitis, 5 and a virus causing atypical pneumonia in human beings 6 all produce meningitis after intracerebral inoculation, and pneumonia after intranasal inoculation in mice, and the lesions thus produced by each of the viruses are practically indistinguishable grossly or microscopically. After intradermal or subcutaneous injection these 4 agents produce granulomatous infiltrations in the skin of experimental animals. Since the development of complement fixation tests for lymphogranuloma venereum, 7 and psittacosis, fixation with sera from venereally exposed but clinically non-lymphogranulomatous persons and certain lymphogranuloma venereum antigens has been observed. 8 False positive complement fixation reactions between psittacosis antigen and sera from syphilitic persons have also been reported. 9 , 10 It was noted particularly 8 that as far as complement fixation between the lymphogranuloma antigen and the sera of venereally exposed persons was concerned, there was no correlation with the results of the Wassermann test. Persons with gonorrhea who had a negative Wassermann reaction gave positive lymphogranuloma fixation in as high a proportion as did syphilitics. The possibility that subclinical infection with the virus of lymphogranuloma venereum might be the common factor in these cross reactions, and the other similarities of the viruses under consideration as noted above, led us to investigate the serological relationship of these viruses.

Therapeutic Effect of Sulfathiazole and Sulfapyridine

Conclusion It has been shown that when the compounds which have been studied are administered as 1 % of the diet, the therapeutic effect of sulfathiazole is equal to that of sulfapyridine. In view of the comparative toxicity and metabolism of these two compounds 2 it is possible that sulfathiazole may be a more desirable therapeutic agent than sulfapyridine.

Relationship of Agents of Trachoma and Inclusion Conjunctivitis to Those of Lymphogranuloma-Psittacosis Group

While the nature of the etiologic agents of trachoma and inclusion blennorrhea is still not indisputably established, they appear to belong to the group of agents generally known as viruses and the great preponderance of evidence points to a causal relationship for the elementary and initial bodies which are characteristically present in the lesions. 1 That these elementary and initial bodies, and other related structures are similar in morphology and dimension to those found in psittacosis and lymphogranuloma venereum has been pointed out.2, 3 Moreover, with the exception of the glycogen reaction, which is positive for the large plaques in trachoma and inclusion blennorrhea, 4 but negative for those in psittacosis and lymphogranuloma venereum, 3 the tinctorial characteristics of the morphological units in all 4 diseases are similar. A further bond between the two groups lies in the fact that of all the so-called virus diseases only 4, namely trachoma, inclusion blennorrhea, lymphogranuloma venereum, pneumonitis of mice, 5 together with the rickettsial infection of heart-water in sheep, 6 are known to respond to chemotherapy with the sulfonamide drugs. It has recently been demonstrated that a powerful complement fixing antigen can be prepared for lymphogranuloma venereum by the propagation of the agent of this disease in the yolk-sac of the embryonated chick egg. 7 Furthermore, it has been shown that this antigen gives marked cross fixation with sera from individuals infected with other members of this group of agents, i. e., psittacosis or pneumonitis. 8 It seemed of interest, therefore, to test the sera of individuals infected with trachoma or inclusion blennorrhea by the same method to see whether any cross-fixation would occur here. The results are shown in Table I. It was found that in the case of adults suffering from chronic trachoma (Institution EI) our usual routine of fixation at 37 C for 1 ½ hours gave fixation at serum titers comparable to those obtained with some lymphogranulomatous sera.

Complement Fixation Test in Lymphogranuloma Venereum

Summary In individuals with lymphogranuloma venereum, the serum has been found to fix complement regularly in the presence of antigens containing the virus in high concentration. Such fixation was observed only once with sera taken from supposedly uninfected individuals but was obtained frequently in syphilitic sera showing markedly positive Wassermann reactions.

A New Material (Lygranum) for Performance of the Frei Test for Lymphogranuloma Venereum.

Conclusions Lygranum antigen is superior to mouse brain antigen in sensitivity and specificity in the performance of the Frei test for lymphogranuloma venereum. Lygranum control is superior also to mouse brain control in producing non-specific reactions in only 2 of 35 persons as compared with 28 of 36 in the case of mouse brain control. In the group of 36 tested only one individual showed a reaction which could be regarded as resulting from hypersensitivity to chick material.

A Rapid Method for Estimation of Penicillin

Summary A rapid test for the estimation of penicillin or other antibiotic agents makes use of the hemolytic property of β streptococci. With optimal conditions, as set out above, results can be read within 55 to 90 minutes.

Action of Sulfathiazole and Sulfamethylthiazole on Staphylococcus aureus

Summary In in vitro experiments with Staphylococcus aureus sulfamethylthiazole has shown greater bacteriostatic activity than sulfathiazole; the activity of the latter was in turn greater than that of sulfapyridine. In in vivo experiments with the same organism sulfapyridine has had little, if any, activity. Both sulfathiazole and sulfamethylthiazole have protected mice and the former drug has been slightly but consistently more active than the latter.

Chemotherapy of Lymphogranuloma Venereum with Sulfonamide Drugs

It was recognized early that in lymphogranuloma venereum, unlike most other virus diseases, some success attended treatment of infected mice or guinea pigs with drugs of the sulfonamide group. The earlier work has been summarized by Findlay. 1 In a previous communication from this laboratory 2 it was indicated that, in preliminary experiments, sulfapyridine and sulfathiazole given orally in the form of the free acid twice daily after infection were equally effective in preventing death of mice infected intracerebrally. In these experiments mouse brain was used as inoculum, and even with a 1 in 10 suspension only 63% of the control mice died. In subsequent papers Findlay 1 , 3 repeated his earlier results with sulfanilamide, showing a reduction of mortality from 84% in the controls to 49% in those fed sulfanilamide in gum acacia daily. 3 He further attempted to assess the relative value of sulfanilamide, sulfapyridine, sulfathiazole, sulfamethylthiazole and disodium 4:4 bis-o-carboxybenzoylaminodiphenylsulfone. 1 The mice received 10 mg per 20 g of body weight in 2 equal daily doses orally by stomach tube for the first 4 compounds and subcutaneously for the last. One hundred mice were treated with each compound, together with 100 controls, and the ratio of treated survivors to control survivors was used as a method of comparing one experiment with another. On the basis of his results, Findlay maintained that the order of activity ran: sulfamethylthiazole > sulfapyridine > sulfathiazole > sulfanilamide > lutazol. Smaller experiments with compounds inoculated intramuscularly in olive oil indicated slight activity for ammonium 4-nitrobenzene-sulfonate and 4:4-dinitrodiphenylsulfone. All of the previous work had been carried out with virus material of low titer derived from infected mouse or monkey brain.