Lagochilascaris major Leiper, 1910
ETYMOLOGY:Lago (Hare) + Chil (Lip) + Ascaris; along with major (due to being larger than the previously described Lagochilascarisminor).
HISTORY: This worm was originally described from a lion from the area of Kilamandjaro, by Leiper in 1910. The next description was presented by Durette (1963) from a lion in the Congo. Clapham (1945) reported on specimens of Lagochilascaris found in an unknown host from West Africa, probably a Harrier Hawk in the genus Lagochilascaris, and it is assumed that this was a spurious finding based on the bird having ingested adult worms. In 1971, Sprent determined that specimens of Lagochilascaris recovered from the esophagus, stomach, and trachea, of a cat in Argentina by Led et al. (1968) were Lagochilascaris major on the basis of the morphology of the lips and the number of pits around the circumference of the eggshell. In 1990, Amato et al., published a report of two cases of two cases of Lagochilascaris major in domestic cats from Petropólis, Brazil, and discussed an earlier unpublished case from a cat that occurred in São Paulo, Brazil.
GEOGRAPHIC LOCATION: Described from domestic cats in Argentina and Brazil and from Lions in Africa.
LOCATION IN HOST: In Argentina, the worms have been described from stomach, esophagus, and trachea (Led et al, 1968). Romero and Led (1985) also described from Argentina a fistulated abscess in the masseter muscle of a cat. In Brazil, the worms in the two cases described by Amato et al. (1990) were recovered from a fistulated abscess at the level of the first pharyngeal ring of each of the two cats. Dell’Porto et al. (1988) described a case of a fistulated abscess in the neck of a cat that contained 35 adult Lagochilascaris major.
PARASITE IDENTIFICATION: Adults of Lagochilascaris tend to be rather small worms with the total length of the males being around 17 to 20 mm and the length of the females being around 18 to 21 mm. The worms are cream colored. The vulva of the female is located at or slightly behind midbody. The lips are a distinguishing feature in that the dorsal lip and each of the subventral lips have a deep central cleft in the anterior border that gives them the typical “hare-lip” appearance. The anterior end of the worm is constricted between the base of the lips and the body of the worm, and there is an inflation of cuticle on the anterior of the worm behind this indentation that has been termed a collar. Extending anteriad from the collar are prolongations called interlabia that protrude forward between each of the three lips. The eggs of Lagochilascaris are the feature that can most easily be used to distinguish Lagochilascaris major from Lagochilascaris minor. Although the eggs are similar in size (around 60 μm in diameter) and general appearance having a thickened brown shell, the eggs of Lagochilascaris major have approximately 33 to 45 pits around the circumference while those of Lagochilascaris minor have approximately 15 to 25 pits around the circumference. In the case of Romero and Led (1985) the eggs from the cat were described as having 29 to 31 pits around the circumference of the eggshell. In the case of Dell’Porto et al. (1988), the eggs were described as having 21 to 31 pits around the circumference of the eggshell. It also appears that the collar is more apparent on the anterior end of Lagochilascaris minor and that the lips of Lagochilascaris major appear to be wider than the collar while those of Lagochilascaris minor tend to be the same width or narrower than the collar.
LIFE CYCLE: The life cycle of Lagochilascaris major has not been described. It is assumed based on work done with Lagochilascaris sprenti by Smith et al. (1983) and by work of Volcan et al. (1992) with Lagochilascaris minor that there is a mammalian intermediate host that has mature larvae in its muscle tissues. The feline host would then become infected by the ingestion of the intermediate host. The embryonated eggs of Lagochilascaris major were fed to a cat and to an opossum (Didelphisazarae), buty neither adult worms or larvae were recovered from these animals at necropsy (Romero and Led, 1985).
CLINICAL PRESENTATION AND PATHOGENESIS: The case described by Led et al. (1968) was a mixed-breed, 8-month-old female cat that had not eaten for three days and which presented with buccal paralysis. This cat died four days after the first signs appeared. In the first presentation of the case of Romero and Led (1985), a total of 6 adult worms were recovered from the abscess. Twenty-six days after the initial presentation, and examination of the abscess revealed another adult male and female worm. Again, 72 days after the first presentation, the abscess was found to contain 24 adult worms. In the case of Dell’Porto et al. (1988), the cat was found to have a fistulated abscess on the neck, and following lavage with physiological saline, a total of 50 male and 65 female worms were recovered. The clinical signs associated with the two cases described by Amato et al. (1990) were weakness, coughing, and an incapability of swallowing. The cats both had abscess on the right side at the level of the first pharyngeal ring. The abscess in one cat contained 45 adult nematodes; the abscess from the other cat contained 31 adult nematodes.
TREATMENT: Romero and Led (1985) treated the cat with oral mebendazole for 7 days, and no worms were observed over the next seven months. However, this treatment was applied after the abscess had been washed on several occasions.
EPIZOOTIOLOGY: Cats are probably being infected by the ingestion of some small rodent intermediate host.
HAZARDS TO OTHER ANIMALS: The eggs are not embryonated when passed, and thus, with routine removal of cat feces, other animals should be protected from infection. However, rodents probably can become infected with this parasite.
HAZARD TO HUMANS: Lagochilascaris major has not been reported from humans. Lagochilascaris minor has been reported
CONTROL/PREVENTION: Because the means by which cats obtain their infection is not clear at this time, it is difficult to determine the best mode of control or prevention. Cats may be acquiring their infection by the ingestion of rodent intermediate hosts, or they may be becoming infected by the ingestion of infective eggs.
REFERENCES:
Armato JFR, Grisi L, Neto MP. 1990. Two cases of fistulated abcesses caused by Lagochilascaris major in the domestic cat. Mem Inst Oswald Cruz, Rio de Janeiro 85:471-473.
Clapham PA. 1945. Some helminths from West Africa. J Helminthol 21:90-92.
Dell’Porto A, Schumaker TTS. 1988. Ocorrencia de Lagochilascaris major Leiper, 1910 em gato `(Felis catus domesticus L.) no estado de São Paulo, Brasil. Rev Fac Med Vet Zootec 25:173-180.
Durette MC. 1963. Remarques sur les anomalies du genre Lagochilascaris. Bull Soc Path Exot 56:129-133.
Led JE, Colombo E, Baraboglia E. 1968. Primera comprobacion en Argentina de parasitismo en gato (Felis catus domesticus) por nematode del genero Lagochilascaris, Leiper 1909. Gaceta Vet, Buenos Aires 30:407-410.
Leiper RT. 1910. Nematodes. Wissenschaftliche ergebnisse der schwedischen zoologischen expedition nach dem Kilimandjaro, dem meru und den umgebenden massaisteppen Deutsch- Ostafrikas 1905-1906 unter letung von Prof. Dr. Yngve Sjöstedt. Hrsq. mit unterstützung von der Konigl. Schwedischen Akademie der Wissenschaften, Stockholm. Vermes 3, 22:23-26.
Romero JR, Led JE. 1985. Neuevo caso de Lagochilascaris major (Leiper 1910) en la República Argentina, parasitando al gato (Felis catus domesticus). Zbl Vet Med B 32:575-582.
Sprent JFA. 1971. A note on Lagochilascaris from the cat in Argentina. Parasitol 63:45-48.
Volcán GS, Medrano CE, Payares G. 1992. Experimental heteroxenous cycle of Lagochilascaris minor Leiper, 1909 (Nematoda:Ascarididae) in white mice and incats. Mem Inst Oswald Cruz, Rio de Janeiro 87:525-532.