Objective: Atrophic body gastritis (ABG) is common in China. Although histology via endoscopy is an efficient and reliable means of diagnosing ABG, it is an invasive procedure. Therefore, in the present study serum pepsinogen (PG) was used as a biomarker to develop a novel noninvasive test as the first option for screening of ABG in certain groups of Chinese.
Methods: The study population consisted of 81 selected dyspeptic patients (mean age, 64.8 +/- 0.7 years; M:F, 43:38) who underwent diagnostic gastroscopy. At least four biopsy specimens were taken from the antrum and corpus of the stomach (two specimens from each site) for histological diagnosis. Blood samples for ELISA assays of serum pepsinogen I (PGI), pepsinogen II (PGII) and IgG antibodies against Helicobacter pylori (Hp IgG) were drawn after endoscopy. Cut-off points were calculated using receiver operating curves (ROC).
Results: There was no correlation between serum PG and atrophy in the antral mucosa. The mean serum concentration of PGI was lower (P < 0.05) in patients with ABG (89.9 microg/L) than in those with normal mucosa (NM) and non-ABG (123.7 microg/L and 139.1 microg/L). The mean ratio of PGI:PGII was also lower (P < 0.01) in patients with ABG (6.2) than in those with NM and non-ABG (11.6 and 11.7). There was no difference in serum PGI or the PGI:PGII ratio between patients with and without H. pylori infection. For diagnosing ABG, the area under the ROC of PGI and the PGI:PGII ratio was 0.741 (95% CI: 0.627-0.856) and 0.874 (95% CI: 0.788-0.961), respectively. The maximum of the Youden's index (YI) of PGI and the PGI:PGII ratio was 0.426 and 0.722, respectively. The best cut-off point for PGI was 97.1 microg/L with sensitivity of 67% and specificity of 76%, and for PGI:PGII ratio was 8.1 microg/L, with sensitivity of 89% and specificity of 83%.
Conclusions: The serum PGI:PGII ratio appears to be a sensitive and specific assay for corpus atrophy, thus providing a noninvasive and indicative test for diagnosis of atrophic gastritis.