Case Report: Successful Treatment of a Patient with Microfilaremic Dirofilariasis Using Doxycycline.

We report the case of a 56-year-old woman with microfilaremic dirofilariasis due to Dirofilaria repens, which is a very rare condition in humans. Of note, just one of six large-volume blood samples of this patient was positive for microfilariae. Polymerase chain reaction (PCR) and sequencing of the parasite gene determined the geographic origin of the causative helminth. The patient was treated successfully with doxycycline. This drug was chosen because of the patient's reluctance to the use of ivermectin and to provide an anthelmintic effect by targeting the bacterial endosymbiont Wolbachia present in most filarial species.