The role of 14C-labelled urea breath test in the diagnosis of Helicobacter pylori infection

Helicobacter pylori infection is the most common infection causing gastritis, peptic ulcer disease, non-ulcer dyspepsia and gastric carcinoma. Diagnostic methods used to determine infection include blood antibody test, stool antigen test, urea breath test and endoscopy. Endoscopy with biopsy is the most reliable procedure, but is associated with several major adverse events including perforation, bleeding and infection.OBJECTIVE: This study aimed to determine the value of 14C-labelled urea breath test in the diagnosis of H. pylori infection, and to determine its sensitivity, specificity, positive and negative predictive values, and accuracy.METHODS: From January to December 2007, 34 subjects were recruited from a tertiary hospital in Metro Manila. All of them underwent both urea breath test and endoscopy. Statistical analysis was performed using endoscopy as the gold standard.RESULTS:The sensitivity and specificity of urea breath test were 90% and 91 %, respectively. Endoscopy with biopsy, histopathologic analysis and rapid urease test is still the gold standard, but it should not be the first procedure to be requested because of the complications associated with this invasive procedure.CONCLUSION: 14C-labelled urea breath test is the safest, fastest, the most non-invasive and therefore the best screening test in the diagnosis of Helicobacter pylori infection.

The value of three-phase bone scintigraphy in the assessment of stress fractures

Stress fractures are overuse injuries of the bones resulting from repetitive stresses. Since symptoms are non-specific, an imaging modality is mandatory for accurate diagnosis. Bone scintigraphy used to be the gold standard in evaluating stress fracture, but the advent of MRI led to its underutilization. This study aims to determine the role of three-phase bone scintigraphy in the assessment of stress fracture, and to determine the sensitivity, specificity, positive and negative predictive values and the accuracy rate of bone scan. In a tertiary hospital in Metro Manila, 15 patients referred for three-phase bone scintigraphy to assess for stress fracture from 2004 to 2006 were included in the study. Of these 15 patients, 12 also underwent MRI. Sensitivity, specificity, positive and negative predictive values, and the accuracy rate were computed with MRI as the gold standard. The sensitivity of bone scans approach 100 percent. However, its specificity is low due to other conditions that can produce a positive scan. Because of the limitations inherent to scintigraphy, MRI could be a valid first-line imaging technique in diagnosing stress fracture. MRI provides a greater anatomic detail of the area in question. It may secure an accurate diagnosis if the fracture line is demonstrated. However, extensive marrow edema precludes the visualization of the fracture line in some cases. Bone scintigraphy together with an accurate history is still a very useful tool in diagnosing stress fracture. MRI should be reserved for cases where the radiographic and scintigraphic findings are indeterminate.