In Europe, zoonotic filarial infections in humans are caused by two species, Dirofilaria immitis and Dirofilaria repens. These parasites are associated mainly with embolic infarcts of the pulmonary artery and subcutaneous nodules, respectively. An unusual dirofilarial infection in a Greek patient who showed marked eosinophilia and microfilaremia is presented. Although the identification of Dirofilaria species is not conclusive, this report is the first on a case of microfilaremia from a Dirofilaria infection in an immunocompetent patient.

Microfilaremia from a Dirofilaria-like parasite in Greece. Case report.

Filarial nematodes with zoonotic potential in ring-tailed coatis (Nasua nasua Linnaeus, 1766, Carnivora: Procyonidae) and domestic dogs from Iguaçu National Park, Brazil

Filariasis is endemic worldwide in the tropical areas. It is uncommon in Saudi Arabia but has been reported from the areas adjoining the Red Sea particularly from the South-Western region. Conventional diagnostic procedures include the demonstration of microfilaria in the blood smears or in the skin snips. Both of these procedures have high false-negative rates. In surgical material the diagnosis is relatively easy when viable filarial worm is present. Necrotic and calcified worms may require special stains for identification. Similarly microfilaria may be missed if you are not aware of the possibility particularly in cases where tissue eosinophilia is absent. The purpose of this paper was to illustrate these examples and to review the appropriate literature in order to make physicians aware of this uncommon entity. This is a retrospective study of three cases of filariasis seen during a period of 20 years (1981-2001) in the Riyadh Armed Forces Hospital (RKH). (excerpt)

Filariasis: a report of three cases.

Crude antigenic preparations from Setaria equina were used in ELISA and Western blotting to examine cross-reaction with human sera from areas endemic for bancroftian filariasis. Sera from normal subjects from non-endemic areas were included as negative controls. Cross-reaction was found between S. equina antigens and antibodies in the sera of Wuchereria bancrofti-infected patients, with the highest levels observed between sera of chronic infected patients and Setaria spp. crude female worm surface antigen (CFSWA). In the absence of active transmission of Setaria spp. infection, CFWSA is useful to detect chronic W. bancrofti infection before patients become symptomatic, particularly when chronic patients are known to be amicrofilaraemic. In the presence of active S. equina infection, antigens from the adult and microfilaraemic stages showed the highest degree of cross-reaction with human sera.

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Cross-reaction of antigen preparations from adult and larval stages of the parasite Setaria equina with sera from infected humans with Wuchereria bancrofti.

Preface. Stealth Parasites: The Under Appreciated Burden of Parasitic Zoonoses in North America J.L. Gauthier, et al. Toxocariasis and Baylisascariasis P.M. Schantz. Trichinellosis D.D. Despommier. Larval Tapeworm Infections: Cysticercosis, Cystic Echinococcosis and Alveolar Echinococcosis A. Flisser. Intestinal Tapeworm Infections D.J. Richardson. Other Noteworthy Zoonotic Helminths D.J. Richardson. Cryptosporidiosis C. Chappell. Toxoplasmosis D.S. Lindsay. Babesiosis P.J. Krause. Other Noteworthy Zoonotic Protozoa O.J. Pung. Zoonotic Arthropod Parasites L.A. Durden. Index.

Northern American parasitic zoonoses

Human infection with a zoonotic Brugia species in the United States is uncommon. Positive identification of the filarial nematode is required for histopathologic diagnosis. Many cases may go unrecognized because of the nonspecific clinical manifestations and the nondiagnostic histologic changes occurring in involved lymph nodes. A case of zoonotic Brugia lymphadenitis is described in a patient from Rhode Island, in which a small nongravid female worm was identified in a lymph node biopsy specimen. The lymph node also showed a spectrum of reactive changes including the presence of florid monocytoid B-cell proliferation, which has not been described in association with zoonotic Brugian filariasis.

Richard M. Dauphinais

Papers

Zoonotic Brugian lymphadenitis. An unusual case with florid monocytoid B-cell proliferation.

Reply by Dr. Dauphinais