CORRESPONDENCE schistosomal polyposis of the colon with niridazole (Ambilhar). Journal of Tropical Medicine and Hygiene, 11,65-67.

Nebel, 0. T., El-Masry, N. A., Castell, D. O., Farid, Z., Fornes, M. F. & Sparks, H. A. (1974). Schistosomal disease of the colon: a reversible form of polyposis. Gastroenterology,

67, 939-943.

This research forms part of Research Project No. M4305.12-5022 of the Bureau of Medicine and Surgery, Department of the Navy, Washington, D.C.

Metastatic spread of Leishmania braziliensis braziliensis to the extremities of hamsters ,%-According to LAINSONand SHAW (1972, 1974) and to my personal observations, until recently no metastatic spread to the extremities has been observed in hamsters after experimental inoculation with leishmaniae of the Leishmania braziliensis complex. I have now observed metastatic spread of lesions to the foot in 2 out of 20 hamsters inoculated with L. braziliensis braziliensis, occurring five months after inoculation. The smears prepared from one of these lesions showed a moderate number of amastigotes as compared to the scanty number of parasites in the site of inoculation (nose). As far as I know, this is the first report of the metastatic spread of L. b. braziliensis to the feet of hamsters. The strain of L. b. braziliensis (N.lOO) was isolated in 1972 from a patient with cutaneous leishmaniasis in Caratinga, Minas Gerais, Brazil, and kindly sent me by INERu (National Institute of Rural Endemics, Brazil). It has been maintained by periodical subinoculations in hamsters, always appearing as typical leishmaniae of the L. braziliensis complex. After inoculation it gives rise to a slowly growing nodule at the site of inoculation, showing marked host cellular response with a scanty number of amastigotes, which are difficult to maintain in NNN media. I am, etc., R.P. BRAZIL Lab. Leishmanioses CPPN-ICB-UFRJ-Cidade Rio de Janeiro, Brazil 6th May 1975

Universitdria,

originally isolated from Rhodnius ecuadorensis in Peru by CUBA et al (1972), heavy growth occurred in Warren’s modified medium at 25-28°C. Ten subpassages were carried out, at one to two weekly intervals; densities of more than 10’ of epimastigotes and trypomastigotes were obtained per ml medium. Equally good growth occurred in 4N and Senekjie’s medium. The T. range11 isolate was sensitive to Mycostatin in the medium. Cultures of the Peruvian T. rangeli were used to infect fourth and fifth instar nymphs of R. prolixus and Panstrongylus megistus by intrahaemocoelic inoculation. Abundant growth occurred in the haemocoele of both species of bugs. High densities of epimastigotes and trypomastigotes were observed from 2-12 weeks after inoculation. The majority of organisms were extracellular but many intracellular forms were observed in the haemocytes. No invasion of the salivary glands was found during periods of observation up to three months. Attempts to transmit trypanosomes by the bite of haemolymph-positive bugs were unsuccessful. The T. rangeli organisms inoculated into the haemocoele also gave rise to concurrent infections in the recta of both species of bugs. These findings suggest that the behaviour of different T. rangeli isolates varies considerably, in vivo and in vitro. Differential diagnosis between T. raweli and T. cruzi based on beha$our in various culture media alone is therefore unreliable, because of the apparent variability of T. rangeli from different geographical areas. In vitro methods should be supplemented by study of the development in the vector and in the mammalian host. We are, etc., E. MINTER-G• EDBLOED* MARIA LAPASANTOSOLIVEIRA *Present address : London School of Hygiene and Tropical Medicine, KeppelSt., London WC1 7HT Chagas’ Disease Research Unit (London School of Hygiene and Tropical Medicine) Caixa Postal, 2087 (RVO), 40.000 Salvador-Bahia, Brazil 18th April 1975 References

References

Lainson, R. & Shaw, J. J. (1972). Leishmaniasis of the New World: taxonomic problems. British Medical Bulletin, 28, 4448.

Lainson, R. & Shaw, J. J. (1974). Las leishmanias y la leishmaniasis de1 nuevo mundo, con particular referencia al Bras& Boletin de la Oficina Sanitaria Panamericana, LXXVI,

89

93-114.

Cuba, C., Morales, N., Fernandez, E. & Fernandez, W. (1972). Hallazgo de Rhodnius ecuadoriensis Lent & Leon 1958 infectado naturalmente por trypanosomas semejantes a Trypanosoma rangeli Tejara, 1920 en Caserios de1 distrito de Cascas, Contumaza, Dpto. de Cajamarca, Peru. Revista do Institute de Medicina Tropical de Srlo Paulo, 14,191-202.

Zeledon. R. (1959). Differentiation of Trvnanosoma rangeh and Schizotrypanum cruzi in a liquid medium, with notes on the nutrition of hemoflagellates. Journal \

Growth characteristics of Trypanosoma SIR-The

rangeli

differential diagnosis between infections with Trypanosoma cruzi and T. rangeli is of practical importance since both species infect similar hosts, including man and Triatomine bugs. Although morphological differentiation is easy, parasitaemia is often of too low a level in the mammal for parasites to be found. Haemoculture in differential media to separate T. cruzi and T. rangeli was suggested by ZELEDON(1959) based on the observation that Warren’s modified medium was inimical to T. rangeli but supported luxuriant growth of T. cruzi. However, during recent experiments with T. rangeli,

of Parasitology,

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I_

45,652.

Malarial oiicysts in Culicoides

sp. in Darjeeling

SIR-For some time we have been engaged in a search for the arthropod vector of the malaria parasite of the flying squirrel. We have now come across oocysts of a malaria parasite in serial sections of a Culicoides sp., picked up at random from light trap collections made during several nights in a flying squirrel-infested area of Darjeeling. Out of 12 insects examined so far in serial sections, two specimens have been found to harbour

Letter: Metastatic spread of Leishmania braziliensis braziliensis to the extremities of hamsters.

CORRESPONDENCE schistosomal polyposis of the colon with niridazole (Ambilhar). Journal of Tropical Medicine and Hygiene, 11,65-67. Nebel, 0. T., El-M...
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