Experimental Observations on the "Cure" of Syphilis in the Rabbit With Arsphenamine

Abstract

The first therapeutic studies of arsphenamine were carried out by Ehrlich and Hata (1) on mice and rats infected with the organism of relapsing fever, on fowls with fowl spirillosis, and on rabbits with experimental syphilis. Rabbits with scrotal chancres were treated with the drug and the rate of healing of the lesion and of the disappearance of treponemata was noted. Rapid disappearance of the clinical phenomena and of the treponemata was interpreted by Ehrlich and Hata to mean that the animals had been sterilized, in other words, that complete biological cure had been obtained. The more recent knowledge of the behavior of syphilis in the rabbit permits us to say that these criteria of cure are altogether insufficient.Kuznitsky (2), working under Neisser's direction, studied the effects of arsphenamine upon syphilis in apes and obtained what he regarded as certain cure in six out of nine animals treated. The criterion for cure adopted by this worker was the success or failure of reinoculation. If reinoculation proved to be successful the animal was regarded as having been rid of all its spirochetes; if unsuccessful, it was thought that infection still existed. In therapeutic experiments with other arsenicals and with various mercurials Neisser (3) had used either the reinoculation method as a criterion of cure, or had inoculated emulsions of internal organs (liver, spleen, bone marrow) of treated animals into normal apes to determine whether

Studies in Experimental Syphilis

“…As they very aptly expressed it, one must be able "to see beyond the reaction at the site of reinoculation." More recently the same question has been raised by other workers in this field (7)(8)(9).…”

Modified method of filtering cerebrospinal fluid and aqueous humour for the detection of treponemes. Proof of the persistence of their vitality in rabbits.

“…Sezary and Paillard (1910) first succeeded in detecting spirochaetes in the CSF and Nichols and Hough (1913) were able to isolate the strain which bears their name.Shortly afterwards, Wile (1917) succeeded, 62 times out of 100, in infecting rabbits with the CSF of a patient suffering from tabes and GPI, and Chesney and Kemp (1924), having similarly inoculated the CSF collected from 34 subjects with primary syphilis and one with syphilitic meningitis, all untreated, obtained six positive responses, although after a long incubation period. Nedden (1906) had reported finding the organism in the aqueous humour of a patient with syphilitic iritis and Stephenson (1907) in that of a young woman with secondary syphilis and iritis.…”