A Comparison of Nested Multiplex-Polymerase Chain Reaction with Indirect Immunofluorescence for Detection and Typing of Herpes Simplex Virus / 대한진단검사의학회지

BACKGROUND: Herpes simplex virus type 1 (HSV-1) is linked specifically to oral and lip infections while HSV-2 is involved in genital infections. We evaluated a recently reported nested-multiplex ploymerase chain reaction (NM-PCR) for the detection and typing of HSV and compared the results with indirect immunofluorescence (IF) after cell culture. METHODS: One hundred thirty three specimens were received from patients suspected of having clinical HSV infections. HSV was cultured by the shell vial method and stained with type specific monoclonal antibodies. NM-PCR was performed using crude samples. RESULTS: HSV was detected in 45 (33.8%) and 46 (34.6%) of the 133 specimens by IF and NMPCR, respectively. All of the HSV IF positive specimens were also positive by NM-PCR. Typing by the two methods concurred in all but two of the 45 specimens; the two specimens were typed as HSV-1 and HSN-2, respectivey, by IF, and both as HSV-1 and HSV-2 by NM-PCR. CONCLUSIONS: Our results suggest that NM-PCR is a rapid and sensitive method for the detection and typing of HSV.

Isolation of the Herpes Simplex Virus by Shell Vial Culture / 대한진단검사의학회지

BACKGROUND: Cell culture is the golden standard method for Herpes simplex virus (HSV) isolation. However, some specimens require many days to develop any cytopathic effect (CPE). We developeda rapid sensitive culture technique for HSV isolations. METHODS: This study included a total of 133 patients with suspected HSV infection. Specimens were centrifuged onto a Vero cell monolayer in a shell vial. The CPE was observed daily during the5-day incubation by inverted-phase microscope. The direct immunofluorescence (DIF) stain with aHSV specific antibody was performed 2 days after sample inoculation. The negative samples in theDIF stain were reinoculated in the new shell vials after extraction of the monolayer. Polymerase chainreaction for HSV detection was performed using the original samples. RESULTS: The CPE was observed 30 (64%), 39 (83%), 43 (92%), 44 (94%), and 46 (98%) cases at1, 2, 3, 4, and 5 days incubation, respectively. The DIF stain detected 46 cases (98%) at 2 days incubation. The CPE was observed in another 7 cases at 1-day incubation after the reinoculation of negative samples. The PCR detected 47 (100%) of 133 cases. CONCLUSIONS: The reinoculation of negative sample in a shell vial culture is a rapid sensitive methodfor HSV isolation.

Genotyping of Vibrio parahaemolyticus by Infrequent Restriction Site Polymerase Chain Reaction / 대한임상미생물학회지

BACKGROUND: Infrequent restriction site PCR (IRS-PCR) is a recently described DNA fingerprinting technique based on selective amplification of restriction endonuclease-cleaved fragments. We applied of IRS-PCR to clinical isolates of Vibrio parahaemolyticus associated with diarrhea. METHODS: IRS-PCR assay was performed with adaptors for XbaI and HhaI restriction sites. A total of 35 strains of V. parahaemolyticus which were isolated from clinical specimens of patients with diarrhea were analyzed. The isolates were collected from different geographic areas of Seoul (n=12), Incheon (n=21) and Gwangju (n=2) during 1998-2000 in Korea. RESULTS: In IRS-PCR, amplifed DNA fragments between 50 and 400 bp were found to be the most reproducible in this study. When V. parahaemolyticus isolates were amplified with AH1 and PX-G as primers, 35 isolates could be grouped into five IRS-PCR patterns: A (n=16), B (n=4), C (n=6), D (n=5) and E (n=4). The patterns were subdivided into 15 subtypes: A1, A2, B1, B2, B3, B4, C1, C2, C3, D1, D2, D3, E1, E2 and E3. The IRS-PCR patterns of V. parahaemolyticus did not show any relationship with serotype or geographic origin, but the isolates from same outbreak produced a same pattern(A1). CONCLUSION: The results provide evidence of the discriminatory power of the IRS-PCR method as it applies to V. parahaemolyticus.

A Case of Cryptococcal Peritonitis and Causative Organisms of Peritonitis in a Continuous Ambulatory Peritoneal Dialysis Patient / 대한임상미생물학회지

Peritonitis in patients on continuous ambulatory peritoneal dialysis (CAPD) remains a major problem. Peritonitis due to Cryptococcus neoformans is an unusual complication. A 68-year-old woman on prednisolone for Behcets disease and adrenal insufficiency was admitted with chronic renal failure and CAPD was initiated. During her stay in hospital, she was treated with multiple antibiotics for urinary tract infection and CAPD peritonitis with methicillin resistant Staphylococcus aureus (MRSA). She was deteriorated insidiously and C. neoformans was cultured in the dialysate but not in the blood, urine and stool. After three days, she died. We reviewed 385 organisms isolated from 1,325 peritoneal dialysate specimens between 1990 and 2002. Staphylococcus aureus was most frequently isolated (22.6%). Fungus comprises 10.1% of the isolated organisms.