Diagnosis of Helicobacter pylori: comparison of an urease test, histological visualization of curved bacteria and culture.
Helicobacter pylori was investigated in 189 patients for culture, microscopic visualization of campylobacter-like organisms (CLO) and a ten minute urease test. In 136 (72%) the bacteria was isolated, and in 98 of them CLO were histologically detected. Specificity, sensitivity, positive and negative predictive values of microscopic visualization of CLO were: 0.77, 0.73, 0.97 and 0.51, respectively; 98 culture-positive patients were urease test positive. Specificity, sensitivity, positive and negative predictive values of the urease test were: 0.83, 0.72, 0.92 and 0.54, respectively. Comparing the urease test with culture of H. pylori combined with microscopic visualization of CLO, its specificity, sensitivity, positive and negative predictive values were: 0.95, 0.71, 0.98 and 0.48, respectively. Probably, these values are not real, since bacteria different from H. pylori could be misclassified as CLO.
Hernández
F
F
Centro de Investigación y Diagnóstico en Parasitología, Facultad de Microbiología Universidad de Costa Rica, San José.
Rivera
P
P
Sigarán
M
M
Miranda
J
J
D004796:Clinical Enzyme Tests; D003470:Culture Media; D016481:Helicobacter Infections / Q000175:diagnosis*; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D011237:Predictive Value of Tests; D011706:Pyloric Antrum / Q000382:microbiology*; D013272:Stomach Diseases / Q000382:microbiology; D014510:Urease
D003470:Culture Media; D014510:Urease