Rev: 02/21/2024
Trichosomoididae or Anatrichosomatidae
Anatrichosominae
Anatrichosoma Smith & Chitwwod, 1954
Parasites of mammals: primates and rodents
Anatrichosoma species are an unusual group of zoonotic trichuroid nematodes.
The type species of the genus, Anatrichoioma cynomolgi is reported from the nasal septa of Macaca fascicularis, the crab-eating macaque monkey, which is also referred to as the cynomolgus maonkey.
The genus Anatrichosoma is sometimes considered to be a member of subfamily. It is similar to the genus Trichosomoides but with the male and female living separately.
Female:
Length 17.8 mm. to 19.33 mm (A. cynopolgi), sharply constricted on one side at the base of the stichocytes; the cuticle is inflated anteriorly and bears laterally two broad longitudinal bands of punctations;
Uterus is packed with bioperculate embryonated eggs; vulval lips are prominent, without appendage, and are located behind the lateral constriction.
Male:
Length 19.1 mm. to 20.7 mm, (A. cynopolgi)
esophagus is about one-third to one-fourth of the body length.
typical trichuroid genitalia
two subventral and at least two pairs of lateral caudal papillae;
cephalic inflation, cirrus and spicules absent.
Ref: Smith and Chitwood, 1954
Nematodes of Anatrichosoma spp have been identified as parasites in opossums in the US (Pence and Little, 1972), rats in the Philippines (Jueco and Zabala, 1990), primates in Africa and Asia (Allen, 1960; Orihel, 1970; Pence and Little, 1972) and tree shrews in Asia (File, 1974). Anatrichsoma cutaneum is a paraesite of the nasal passages of primates. Nematodes of the genus have also been identified occasionally in humans, in mouth lesions (Eberhard et al., 2010; Nunez, 2010) and even the breast (Pampiglione et al., 2005).
Due to limited knowledge of their life cycle and diagnostic challenges, prior to 2013, anatrichosomiasis had been reported only 3 times in domestic animals. A short-haired cat from central Windhoek, Namibia, presented with ulceration, swelling, and sepsis on all four paws, a severe generalized lymphadenopathy and considerable invasive eosinophilia. Histological analysis revealed epidermal hyperplasia, with severe serocellular crusting on the skin surface. One specimen revealed a series of thick-walled eggs within nematode segments with a few sections containing eggs with bioperculate appearance, typical of the genus Anatrichosoma. Ivermectin treatment completely cleared the condition (Nodena ety al., 2013)..
The life cycle of Anatrichosoma spp. remains unknown. Infections are normally recognized through the observation of adult worms from biopsy rather than the recovery of eggs. Their embryonated eggs are known to be sloughed off from female worms in what are described as trails; eggs are swallowed and passed out of the feces of the infected animal (Orihel, 1970)
Nodena, B.H., Du Plessis, E.C., Morkel, C., Tubbesing, U., Soni, M. 2013. Anatrichosoma sp. in the footpads of a cat: Diagnosis and pathology of Namibian case. Veterinary Parasitology 191:386-389,
Oribel, T.C. 1970. Anatrichosomiasis in African monkeys J. Parasitol 56:982-965.
Smith, W.N. and Chitwood, M.B. 1954. Anatrichosoma cynomolgi, a new trichurid nematode from monkeys. J. Parsitol 40 Suppl: 12pp.