Identification of Dirofilaria in man by multilocus electrophoretic analysis

Biochemical keys based on the electrophoretic patterns of nine enzymatic loci diagnostic between Dirofilaria repens and D. immitis were used to examine an immature female of Dirofilaria removed from a 32-year-old woman resident in Caserta, Italy. The worm, tentatively assigned on a morphological basis to D. conjunctivae-D. repens, showed at all the loci examined the same electrophoretic pattern as an Italian dog strain of D. repens. This genetic evidence is in substantial agreement with the hypothesis, already supported by morphological and epidemiological data, that D. conjunctivae (Addario, 1885) Desportes, 1939-1940 and D. repens Railliet and Henry, 1911 should be considered as synonyms. According to the law of priority D. conjunctivae should be the valid name for the species; however, it is proposed to preserve the name repens, well-established for the dog subcutaneous filaria. Multilocus electrophoretic analysis appears to be a valuable tool for the identification of aetiological agents of human zoonotic filariae, particularly in areas where more than one species of the subgenus Nochtiella are present.