Genotyping of clinical and environmental Aspergillus flavus isolates from Iran using microsatellites

Aspergillus flavus is the second most important Aspergillus species causing human infections in tropical countries. Despite an increasing number of infections of A. flavus in Iran, the molecular epidemiology of clinical and environmental strains has not been well studied. We used a panel of nine microsatellite markers to analyse the genetic relatedness of A. flavus. Microsatellite typing of 143 (n = 119 clinical and n = 24 environmental) isolates demonstrated 118 different genotypes. A possible outbreak at a pulmonary ward was discovered. The discriminatory power for the individual markers ranged from 0.4812 to 0.9457 and the panel of all nine markers combined yielded a diversity index of 0.9948. This high-resolution typing method assists in better understanding of the molecular epidemiology of A. flavus.

Accuracy of serum pepsinogens I and II, gastrin-17 and anti-helicobacter pylori antibodies in histological diagnoses of atrophic gastritis

AIM

Atrophic gastritis is defined as a chronic inflammatory process in gastric mucosa leading to loss of glandular cells. It is considered a precancerous condition, thus its early diagnosis is of importance. Although histo-pathologic studies remain as the gold standard of diagnosis, non-invasive methods suitable for screening purposes are being developed. This includes measurement of serum gastric profile.

METHODS

Two hundred and fifty 250 patients who were planned to undergo upper gastrointestinal endoscopy were randomly selected to be included in this study. Serum levels of pepsinogen I and II, gastrin-17 and anti-Helicobacter pylori (Hp) antibody were measured and the results were compared with that of histopathologic assessment of biopsy specimens obtained during endoscopy.

RESULTS

IgG anti-Hp, PGII and PGI/PGII ratio showed correlation with age. PGI/PGII ratio showed best sensitivity (96.1%) and negative predictive value (97.7%). PGI has the highest specificity (94.6%), and PGII also had a high negative predictive value (90.7%). IgG anti-Hp showed poor sensitivity and specificity (58.8% and 26.5%, respectively).

CONCLUSIONS

Pepsinogen I/II ratio appears to be the most suitable single measurement for screening purposes in atrophic gastritis.