SciELO - Scientific Electronic Library Online

vol.37 issue2The experimental granuloma: a hypothesis to explain the persistence of the lesionA case of mycotic keratitis caused by Fusarium solani author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand




Related links


Revista do Instituto de Medicina Tropical de São Paulo

On-line version ISSN 1678-9946

Rev. Inst. Med. trop. S. Paulo vol.37 no.2 São Paulo Mar./Apr. 1995 



Mammomanogamus (Syngamus) laryngeus infection: a new Brazilian human case



Ana Lúcia Freitas; Geraldo De Carli; Maria Helena Blankenhein

Laboratório de Parasitologia, Faculdade de Farmácia, UFRGS, Porto Alegre, RS, Brazil

Correspondence to



The nematode Mammomanogamus (Syngamus) laryngeus is commonly found in the upper respiratory tract of ruminants including domestic cattle, water buffalo, and goats. Humans can be accidentally infected with this parasite. The worms live attached in the mucosa of laryngotracheal region, and usually the symptoms express tracheolaryngeal irritation, with stubborn cough without fever. In some patients there is hemoptysis. These worms remain in permanent copula so that the pair appears as a "Y". The life cycle of M. (S.) laryngeus has not been elucidated.

These parasites were discovered by KING in January, 1913 (LEIPER, 1913) 8 in the sputum of an Irish woman in Santa Lucia, Antilles. Infection of man by this nematode is rare, but the worms have been described in Australia, Brazil, British Guiana, Canada, Martinique, Philippines, Puerto Rico, St. Lucia (West Indies) and Trinidad, and the United States of America. Up to the present, 86 cases of human infection with M. (S.) laryngeus have been reported (St. JOHN et al 21; JUNG et al. 6; DUFAT et al. 4; WEINSTEIN & MOLAVI 24; BIRREL et al. 2; MORNEX et al. 17; TIMMONS et al. 22; GARDINER & SCHANTZ 5; LEERS et al.7; SANTOS et al. 19 and SEVERO et al.20).

In the Brazilian reports there are 21 cases of human parasitism by M. (S.) laryngeus. All of these are, apparently, accidental infections with the bovine species.

These worms were first described from Brazilian patients in the early 1920s by TRAVASSOS (1921) 23 in Salvador, Bahia. Other cases have been reported by MACHADO (1938) 13; MELLO & MELLO (1938) 14; LENT & PENNA (1939) 10; MORAES (1947) 16; PASSOS & BARBOSA (1948) 18; LIMA & BARBOSA (1951) 9; AMARAL, et al. (1954) 1; MACHADO et al. (1962) 12; LONDERO & LAUDA, 1967 11; BUSETTI et al. (1983) 3; MELO et al. (1984) 15; SANTOS et al. (1986) 19, SEVERO et al. (1988) 20, and finally ZUNINO et al. (1989) 25 described six additional cases.

The aim of this communication is to describe a new Brazilian case of syngamosis in a human being. The patient, a 33-year-old white man, veterinarian, from Santa Maria, RS, Brazil, eliminated the worms in July 1992 by spontaneous expectoration after violent attacks of coughing.

The specimens received for morphologic diagnostic reached our laboratory poorly preserved and damaged. To secure a proper preparation, the mucus and adherent debris were carefully removed from the worms by gently shaking in physiological saline. The parasites were fixed in alcohol-formalin-acetic acid (AFA) for 24 h and were stored in alcohol-glycerin.

The female and the male measured 9.0mm and 3.2mm respectively. The anterior extremity of the female showed a large buccal capsule with eight triangular teeth at base (Fig. 1). The male was attached to the female by the copulatory bursa, in the typical "Y" - shaped appearance (Fig. 2). Figure 3 shows the typical posterior extremity of the female, while Fig. 4 shows the anterior extremity of the male, and Fig. 5 shows the eggs. The stool and sputum examination was not performed.



1. AMARAL, A.D.F.; QUAGLIA, F.O. & INOUE, C.R. - Sobre novo caso de singamose humana. Rev. méd. S. Paulo, 38: 1-9, 1954.         [ Links ]

2. BIRREL, D.J.; MOORHOUSE, D.E.; GARDNER, M.A. & MAY, C.S. - Chronic cough and haemoptysis due to a nematode Syngamus laryngeus. Aust. N. Z. J. Med., 8: 168-170, 1978.         [ Links ]

3. BUSETTI, E.T.; SOCCOL, V.T.; RUIS, M.C.E. & CHRISTO, S.W. - Mammomanogamus laryngeus (Syngamidae). Ocorrência parasitária no homem. In: CONGRESO DE LA FEDERACIÓN LATINOAMERICANA DE PARASITOLOGOS, 6., CONGRESSO DA SOCIEDADE BRASILEIRA DE PARASITOLOGIA, 8. & JORNADA PAULISTA DE PARASITOLOGIA, 5., São Paulo, 1983. Resumos. p. 105.         [ Links ]

4. DUFAT, R.; SANG, H.T.; HERRENSCHMIDT, J.L.; VERGEZ, P. & ANDRÉ, J. - A propos d'un nouveau cas de syngamose bronchique humaine en provence de la Martinique. J. franç. Méd. Chir. thor., 25: 547-554, 1971.         [ Links ]

5. GARDINER, C.H. & SCHANTZ, P.M. - Mammomanogamus infection in a human. Amer. J. trop. Med. Hyg., 32: 995-997, 1983.         [ Links ]

6. JUNG, C.; PHILBERT, M. & SANG, H.T. - Une observation de syngamose humaine à localisation bronchique. Premier cas traité et gueri par le thiabendazole. Bull. Soc. Path. exot., 63: 483-488, 1970.         [ Links ]

7. LEERS, W.D.; SARIN, M.K. & ARTHURS, K. - Syngamosis, a unusual cause of asthma: the first reported case in Canada. Canad. med. Ass. J., 132: 269-270, 1985.         [ Links ]

8. LEIPER, R.T. - Gapes in man, an occasional helminthic infection: a notice of its discovery by Dr. King in St. Lucia. Lancet, 1: 170, 1913.         [ Links ]

9. LIMA, L.I. & BARBOSA, F. - Considerações em caso de singamose humana. Publ. avul. Inst. Ageu Magalhães, 1: 27-34, 1951.         [ Links ]

10. LENT, H. & PENNA, M. - Novo caso de singamose em homem no Brasil. Hospital (Rio de J.), 6: 111-118, 1939.         [ Links ]

11. LONDERO, A.T. & LAUDA, P. - Infecção humana por Syngamus laryngeus. Hospital (Rio de J.), 72: 329-331, 1967.         [ Links ]

12. MACHADO, J.M.; DAVIDSON, S. & LOURES, J.C. - Mais um caso de singamose humana. Atas Soc. Biol. Rio de J., 6: 18-20, 1962.         [ Links ]

13. MACHADO, O. - Sobre Syngamus laryngeus (caracteres dos exemplares encontrados em um caso de Singamose no homem). Bol. Inst. Vital Brasil, 22: 61-68, 1938.         [ Links ]

14. MELLO, M. & MELLO, S. - Syngamus laryngeus no homem. Rev. flum. Med., 3: 457-460, 1938.         [ Links ]

15. MELO, A.L.; TEIXEIRA, A.S.; GUERRA, A.F.M.; FORTINI, M.S. & FULGÊNCIO, M.S.T. - Parasitismo da rinofaringe pelo Syngamus laryngeus. J. bras. Med., 46: 94-96, 1984.         [ Links ]

16. MORAES, R.G. - Parasitismo humano pelo Syngamus laryngeus. Arch. bras. Med., 37: 97-101, 1947.         [ Links ]

17. MORNE. J.F.; MAGDELEINE, J. & THORÉ, J. - La syngamose humaine (Mammomanogamus nasicola), cause de toux chronique en Martinique: 37 observations recents. Nouv. Presse méd., 47: 3628, 1980.         [ Links ]

18. PASSOS, W. & BARBOSA, N.C. - Syngamus laryngeus na espécie humana. Rev. bras. Med., 5: 340, 1948.         [ Links ]

19. SANTOS, V.A.; VILELA, M.S.H. & SERRA, R.G. - Ocorrência de um novo caso de singamose humana em São Paulo. Rev. Inst. Med. trop. S. Paulo, 28: 358-363, 1986.         [ Links ]

20. SEVERO, L.C.; CONCI, L.M.A.; CAMARGO, J.J.P.; ANDRADE-ALVES, M.R. & PALOMBINI, B.C. - Syngamosis: two new Brazilian cases and evidence of a possible pulmonary cycle. Trans. roy. Soc. trop. Med. Hyg., 82: 467-468, 1988.         [ Links ]

21. St. JOHN, J.H.; SIMMONS, J.S. & GARDNER, L.L. - Infestation of the lung by a nematode of the genus Cyathostoma. J. Amer. med. Ass., 92: 1816-1818, 1929.         [ Links ]

22. TIMMONS, R.F.; BOWERS, R.E. & PRICE, D.L. - Infection of the respiratory tract with Mammomanogamus (Syngamus) laryngeus: a new case in Largo, Florida, and a summary of previously report cases. Amer. Rev. resp. Dis., 128: 566-569, 1983.         [ Links ]

23. TRAVASSOS, L. - Notas helmintológicas. Brasil-méd., 35: 67, 1921.         [ Links ]

24. WEINSTEIN, L. & MOLAVI, A. - Syngamus laryngeus infection (syngamosis) with chronic cough. Ann. intern. Med., 74: 577-580, 1971.         [ Links ]

25. ZUNINO, J.N.; MORITZ, D.E.; ZOCCOLI, CM. & BARTH, V.L. - Descrição de seis casos de singamose em Florianópolis. In: CONGRESSO DA SOCIEDADE BRASILEIRA DE MEDICINA TROPICAL, 25., Florianópolis, 1989. Resumos. p. 213.         [ Links ]



Correspondence to:
Prof. Geraldo A. De Carli
Rua Cel. Lucas de Oliveira 597/302
90440-011, Porto Alegre, RS, Brazil

Recebido para publicação em 18/07/1994.
Aceito para publicação em 12/09/1994.

Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License