BACKGROUND: Due to a reduction in the number of parasite infections, attention paid to the importance of intestinal parasites has decreased. However, intestinal parasite infections remain ubiquitous and have reappeared as a growing problem in recent decades due to changing lifestyles such as increased overseas travel. In this study, we evaluated trends in intestinal parasite infection using stool examination in a single institute. METHODS: From January 2003 to December 2012, we reviewed all stool examination results performed at Samsung Medical Center. Fecal examinations were performed by formalin-ether sedimentation. RESULTS: A total 429,866 stool examinations were performed resulting in 14,672 cases with positive findings of helminth eggs or protozoan cysts, of which the positive rate was 3.41% on average. The annual positive rate decreased from 5.68% in 2003 to 2.43% in 2012. The positive rate of intestinal parasites, excepting Endolimax nana and Entamoeba coli, was 1.52% on average. Positive rates decreased from 2.13% to 1.10% for helminth egg detections and from 2.55% to 1.30% for protozoan cyst detections during the same time period. Among nematodes, Trichuris tricuria was the most common and had an increasing positive rate after 2010. Clonorchis sinensis was the most prevalent trematode parasite, with an annual average of 528 cases. CONCLUSION: Infection rates of intestinal parasites have decreased over the last 10 years. However, Trichuris tricuria has reappeared and has become a major contributor to parasite infections. Further education and control efforts are needed for greater prevention and eventual eradication of parasitic infections.
Clonorchis sinensis ; Eggs ; Endolimax ; Entamoeba ; Helminths ; Korea ; Life Style ; Ovum ; Parasites ; Trichuris

Bacillus Calmette-Guerin (BCG) has been traditionally used as a vaccine against tuberculosis. Further, intravesical administration of BCG has been shown to be effective in treating bladder cancer. Although BCG contains a live attenuated strain of Mycobacterium bovis, complications such as M. bovis BCG infection caused by BCG administration are extremely rare. Here, we report a case of BCG infection occurring after intravesical BCG therapy. A 67-yr-old man presented with azotemia and weight loss. He had been diagnosed with bladder cancer 4 yr back, and had undergone transurethral resection of the bladder tumor and intravesical BCG (Tice strain) therapy at that time. An acid-fast bacterial strain was isolated from his urine sample. We did not detect Mycobacterium tuberculosis protein 64 (MPT-64) antigen in the isolates obtained from his sample, and multiplex PCR and PCR-reverse blot hybridization assay indicated that the isolate was a member of the M. tuberculosis complex, but was not M. tuberculosis. Finally, sequence analysis of 16S ribosomal RNA and DNA gyrase, subunit B (gyrB) suggested that the organism was M. bovis or M. bovis BCG. Although we could not confirm that M. bovis BCG was the causative agent, the results of the 3 molecular methods and the MPT-64 antigen assay suggest this finding. This is an important finding, especially because M. bovis BCG cannot be identified using common commercial molecular genetics tools.
Administration, Intravesical ; Aged ; BCG Vaccine/administration & dosage/*adverse effects ; DNA Gyrase/genetics ; Humans ; Male ; Mycobacterium Infections/*diagnosis/etiology ; Mycobacterium bovis/genetics/*isolation & purification ; Polymerase Chain Reaction ; RNA, Ribosomal, 16S/genetics ; Urinary Bladder Neoplasms/*therapy