Comparison of Detection Methods and Culture Media for Isolation of Helicobacter pylori from Gastric Biopsy Specimens / 대한임상병리학회지

BACKGROUND: Helicobacter pylori(H. pylori) has been implicated in the pathogenesis of chronic active gastritis and peptic ulcer disease. All patients with ulcers who are infected with H. pylori receive antimicrobial therapy. Therefore diagnosis of H. pylori infection is imperative for the treatment gastritis or ulcer patients. We evaluated the four diagnostic methods and three culture media for the isolation of H. pylori. MATERIALS AND METHODS: Rapid urease test(CLO test), modified Gram stain, culture, and nested polymerase chain reaction (PCR) were performed with 108 gastroscopic biopsy specimens from patients with peptic ulcer or chronic gastritis. Among them 40 specimens were inoculated onto each of 5% sheep blood agar, e99 Yolk emulsion (EYE) agar, and 7% horse blood agar containing antibiotics. RESULTS: The positive rates were the highest by the PCR(72%), 67% by modified Gram stain, 64% by CLO test, and 57% by culture. Among the three media the horse blood agar (selective medial) gave the highest isolation rate (48%), followed by sheep blood agar (45%), and EYE agar (38%). CONCLUSION: Though PCR was the most sensitive method for the detection H. pylori modified Gram stain was sensitive enough, simple, rapid, and economical as the routine diagnostic method of H. pylori. For the culture of H. pylori combination of sheep blood agar as nonselective media and horse blood agar as selective media would show the highest isolation rate.

Two Cases of Diarrheal Disease Caused by Plesiomonas shigelloides / 대한임상병리학회지

Plesiomonas shigelloides is known to cause diarrhea in human. It is a facultatively anaerobic gram-negative rod belonging to the family Vibrionaceae. We isolated P. shigelloides from two patients with diarrhea, a 62-year-old woman with steroid therapy and a 4-year-old boy with no predisposing factor. The organisms were isolated on enteric agars as a nonlactose fermenter and were identified by oxidase, indole, and other biochemical characteristics. The isolates were susceptible to commonly used antimicrobial agents with the exception of ampicillin. P. shigelloides infection is rarely reported in our country, but appears to be a significant cause of diarrhea that responds to antimicrobial therapy. Therefore we suggest the need for correctly identifying P. shigelloides.