Comparison of three urease tests for detection of Helicobacter pylori in gastric biopsy specimens.
OBJECTIVE
To propose two modified urease tests for the detection of Helicobacter pylori in gastric biopsy specimens.


METHODS
The presence of H. pylori infection was determined in 237 patients undergoing upper gastrointestinal endoscopy. Three media were used for the urease tests: Christensen's 2% urea broth and two urea agar media, modified by increasing the concentration of urea (to 4% and 10%) and phenol red and omitting the nutrients.


RESULTS
The modified tests had good sensitivity (> 78%), specificity (96%) and accuracy (> or = 86%) at 2 h using small amounts (15%) of biopsy homogenates. They were statistically more sensitive and accurate than Christensen's broth.


CONCLUSIONS
Both the modified 4% and 10% urea agar tests are simple, sensitive and specific and can be performed with small amounts of sample.
Department of Microbiology, Medical University, Sofia, Bulgaria.
L
L
Boyanova
I
I
Stancheva
D
D
Todorov
R
R
Kumanova
S
S
Petrov
B
B
Vladimirov
N
N
Pehlivanov
R
R
Mitova
I
I
Chakarski
I
I
Churchev
D001431:Bacteriological Techniques; D001706:Biopsy; D005767:Gastrointestinal Diseases / Q000382:microbiology* / Q000473:pathology; D016481:Helicobacter Infections / Q000175:diagnosis*; D016480:Helicobacter pylori / Q000201:enzymology / Q000302:isolation & purification*; D006652:Histological Techniques; D006801:Humans; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D014510:Urease / Q000032:analysis*
D014510:Urease