Gastric emptying characteristics of a novel (13)C-octanoate-labeled muffin meal.

GOALS: Determine the gastric emptying characteristics of a novel, 350-kcal test meal consisting of two muffins, using scintigraphy and the 13C-octanoate breath test (OBT). STUDY: Healthy volunteers underwent three studies on separate days within a 1-week period. On day 1, we measured emptying of the 350-kcal muffin test meal labeled simultaneously with 99mTc sulfur colloid and 13C-octanoate. On day 2, reproducibility of the OBT using a single-labeled 350-kcal test meal was assessed. On day 3, the effect of erythromycin on the 350-kcal OBT was determined. RESULTS: The mean (+/-SD) half-emptying time (T1/2) as measured by scintigraphy was 104 +/- 24 minutes, versus 212 +/- 52 minutes by OBT. There was a strong correlation between T1/2 determined by scintigraphy and the breath test (r = 0.83). Multiple linear regression analysis identified a significant relationship between T1/2 determined by scintigraphy and the 90-and 180-minute breath samples. There was a strong correlation (r = 0.830, slope = 0.732 +/- 0.120 [SE], intercept = 26.4 +/- 12.7) between the T1/2 obtained using the regression equation and the actual T1/2 obtained by scintigraphy. The mean T1/2 (+/-SD) for replicate determinations using the OBT was 209 +/- 52 minutes, compared with 196 +/- 42 minutes on days 1 and 2, respectively (not significant, p = 0.28, paired Student t test). Treatment with erythromycin on day 3 produced a significant decrease in T1/2 (155 +/- 49 minutes, p = 0.002). CONCLUSIONS: The 350-kcal muffin meal OBT provides a convenient, nonscintigraphic way of measuring solid-phase gastric emptying. Multiple linear regression appears promising as a method of analyzing OBT data and may allow for an abbreviated breath test protocol.

Duration of postoperative antibiotic therapy following revision for infected knee and hip arthroplasties.

In the period from 1990 to 1998 28 patients (14 males and 14 females) were treated for infected hip (19 cases) and knee (9 cases) arthroplasties. The median age at index operation was 72 y (range 34-82 y) and at revision surgery 74 y (range 36-83 y). The primary diagnosis was osteoarthritis (16 cases), rheumatoid arthritis (5 cases), failed femoral neck fracture (6 cases) and arthritis secondary to congenital hip dislocation (1 case). Nine cases were infected early, i.e. within 3 months postoperatively, and 19 had late infections. The median interval from index operation to diagnosis of the infected arthroplasty was 18 months (range 1-156 months). Postoperatively, all patients received antibiotics based on susceptibility studies of the causative organism according to culture specimens. The erythrocyte sedimentation rate and CRP level were controlled twice a week during hospitalization and antibiotics were continued until normalization of CRP. The indication for the shift from intravenous to oral antibiotics was a rapid fall in CRP. Antibiotic therapy was terminated when CRP was close to or below 10 mg/l and there was evidence of clinical recovery. Based on the screening of ESR and CRP in this study we believe that CRP is a valuable parameter in deciding when to stop antibiotic therapy. However, it is not clear whether a shorter treatment period is effective or not.

A comparison of three fingerstick, whole blood antibody tests for Helicobacter pylori infection: a United States, multicenter trial.

OBJECTIVE: We compared three whole blood antibody tests for Helicobacter pylori (H. pylori) in a United States, multicenter trial. METHODS: Patients referred for EGD at three medical centers were recruited. During EGD, biopsies were taken for histology and rapid urease testing (RUT). Immediately after endoscopy, patients underwent the antibody tests (FlexPack HP, Abbott Diagnostics; QuikVue, Quidel Corporation; AccuMeter, ChemTrak) using whole blood obtained by two to three fingersticks. Performance characteristics were calculated for each antibody test using the biopsy-based methods as a gold standard. RESULTS: A total of 131 patients participated; 50 (38%) patients had histological evidence of H. pylori infection. Using histology as a gold standard, the sensitivities of FlexPack HP, QuikVue, and Accumeter were 76%, 78%, and 84%, respectively. Specificity was 79% with FlexPack HP and 90% with QuikVue and Accumeter. There were no significant differences in the performance of the three antibody tests though there was a trend toward superior performance for AccuMeter compared to FlexPack HP (p = 0.019). However, RUT proved superior to FlexPack HP using histology as a gold standard (p = 0.008). Using either concordant histology and RUT results or a positive histology or RUT to define active H. pylori infection, there was no statistically significant difference between the antibody tests. CONCLUSIONS: There were no statistically significant differences in the performance of the three antibody tests. These tests proved only marginally sensitive in detecting patients infected with H. pylori. Clinicians should be aware of the limitations of these tests, particularly when using them as a sole means of testing for H. pylori.