Biliary giardiasis in raccoons (Procyon lotor)

Giardiasisis one of the most significant gastrointestinal diseases caused by a cosmopolitan protozoa Giardia duodenalis. The infection occurs in many animals, including wild raccoons (Procyonlotor), that may play a role in disseminating Giardia cysts into the environment and transmitting it to humans and domestic animals. Giardiasis has various clinical manifestations, including diarrhea, abdominal cramps, and upset stomach or nausea. Active trophozoites normally attach to the mucous membrane of the duodenum and upper jejunum, however few cases of biliarygiardiasis have been reported in humans. The aim of this study was to analyze the occurrence of Giardia localization in the gall bladder of raccoons. Bile and feces samples collected from each of the 34 test animals were used for the study. Giardia specific antigen was detected by a rapid immunochromatographic test using stool and bile samples. The overall prevalence was 38.2% (13/34, 95% CI, 21.0-55.4%). Positive results were obtained from 8 stool samples 23.5% (95% CI, 8.5-38.6%) and 13 bile samples 38.2% (95% CI, 21.0-55.4%). In all stool-positive raccoons, the infestation was confirmed by bile examination. In five cases a positive result was obtained only from the bile sample. The detection of the specific antigen GSA65 in the bile of the studied raccoons confirms that, similarly to humans, also in animals in the course of Giardia infection trophozoites can be localized both in the intestine and in the bile ducts.