A total of 30 patients were included of whom nine were women. The average age was 65 years, varying between 40 and 87. Ten patients (33.3%) were operated laparoscopically. The perforation was found prepyloric in 11 patients, at the site of the pylorus in eight patients and postpyloric in 11 patients.
A total of five (16.7%) patients had a history of PUD. Ten patients (33.3%) used NSAID’s, two patients (6.7%) used steroids, three patients (10.0%) used acid reducers, and one patient (3.3%) used a proton pump inhibitor (PPI) before admission to the hospital. The average hospital stay was 11.9 days, varying between 3 and 37 days.
Fluid from the nasogastric tube was obtained from 25 patients, lavage fluid from 26 patients, serum samples from 20 patients, and ulcer biopsies from 18 patients. The results of the genotyping are depicted in Table 1.
The β-globin determination was performed as a control. In nine samples of nasogastric tube fluid and in two samples of lavage fluid it was negative, rendering these results as unreliable. Therefore, these results were excluded from further analysis.
Table 2 represents the frequency of the individual genes and the allelic types found in the different samples by means of PCR and LiPA.
These tables show that for vacA the allelic type s1 is predominantly present in all three types of samples. In the s1 positive strains, subtype s1a is predominant as depicted in Table 3.
With regard to the middle region of vacA the incidence of m1 allelic type is slightly higher; however, the difference is less outspoken compared to s1. The m2a was the only subtype that was found in the samples. In three samples, the genotyping was incomplete (Tables 1 and 2), meaning that determination of the middle region was not possible. This was most likely caused by the small number of bacteria present in those samples.
With regard to the secondary aim of this study, analyzing possibilities to diagnose H. pylori presence in another fashion than through biopsy, the H. pylori status found in each type of sample was compared. A correlation was found between the H. pylori presence in biopsy and its presence in lavage fluid (Fisher’s exact test, p = 0.015), indicating lavage fluid is a valid alternative for determination of H. pylori infection.
The sensitivity and specificity of the lavage fluid analysis was calculated, considering biopsy as a golden standard. Fourteen patients, of which the lavage fluid as well as the biopsy was analyzed, were included into this calculation (patients 2, 4, 5, 6, 8, 10, 15, 23–25, 27–30, Table 1), which is shown in Table 4. Of the remaining patients, either the biopsy or the lavage fluid was missing; therefore, these data cannot be used in the sensitivity/specificity calculation.
The sensitivity was 100%, which means that in case of the presence of H. pylori in the biopsy specimen, the lavage fluid analysis detected it in 100% of cases. The specificity of lavage fluid analysis was 66.7%, which means the chance for false-positives is over 30%. With regard to gender, age, BMI, history of PUD, location of perforation, complications after procedure, and use of steroids, PPI, or antihistaminic medication, no statistically significant correlation was found.