Culture and histologic examination are considered "gold standard" methods for the detection of Helicobacter pylori, but discrepancies may occur with either method. Failure to detect Helicobacter pylori may be due to sampling error, inappropriate transport or culture media, or insufficient duration of the incubation period. Rates of detection of Helicobacter pylori by culture and histopathologic examination of gastric mucosal biopsy specimens were determined in 102 consecutive dyspeptic patients. In a separate group of 60 patients, rates of detection of Helicobacter pylori by culture of antral brushings and the length of incubation required in selective and nonselective culture media were studied. In the first group of 102 patients, the combination of culture and histologic examination detected 54 Helicobacter pylori-positive patients, whereas the separate techniques each detected 51 Helicobacter pylori-positive patients. In the second group of 60 patients evaluated by culture of antral brushings, the rate of detection of Helicobacter pylori was 25 of 60 and was similar for culture (25/60) and histologic examination (25/60). In the second group the length of incubation required to detect Helicobacter pylori was different for selective and nonselective media. In nonselective media, incubation of up to ten days was required to detect all Helicobacter pylori infections, whereas in selective media seven days was sufficient. Rates of detection of Helicobacter pylori by culture, histopathologic examination and culture from brushings were similar, whereas the combination of culture and histopathologic examination achieved a superior rate of detection. The incubation period required for the detection of Helicobacter pylori by culture was a minimum of seven days and was dependent on the culture medium used.