Analysis and evaluation of droplet digital PCR for H.pylori infections in chronic tonsillitis

Abstract

Objective:To investigate the measurement effect of droplet digital PCR(dd-PCR) for H.pylori infections in chronic tonsillitis and explore the correlations between H.pylori infections and chronic tonsillitis.Method:The subjects consisted of 48 chronic tonsillitis patients aged between 7 and 52 years scheduled for tonsillectomy.Core biopsy samples from resected tonsillary tissue was tested for H.pylori detection using both RT-PCR and dd-PCR for the CagA and VacA genes.Preoperative patient venous blood samples were also tested for H.pylori antibodies by Enzyme-linked immunosorbent assay(ELISA).ELISA,RT-PCR and dd-PCR were also used to detect expression of CagA and VacA genes in plasma and tissue of 30 cases of obstructive sleep apnea syndrome(OSAHS) and 35 cases of plasma from healthy subjects.Result:The expression of H.pylori antibodies is tested in plasma:48 chronic tonsillitis patients(10.12±3.23)ng/ml, OSAS(9.87±2.43)ng/ml, healthy subjects(9.34±3.38) ng/ml.There was no significant difference between groups in the plasma.The VacA and CagA gene sequences were detected by RT-PCR:48 chronic tonsillitis patients VacA(27.1%),CagA(16.7%),VacA+CagA(16.7%);30 OSAHS,VacA(23.3%),CagA(20.0%),VacA+CagA(16.7%);all of which were also positive by dd-PCR,thus were considered H.pylori infected.Moreover,The expression of VacA and CagA increased in tissues testing by dd-PCR:48 chronic tonsillitis patients VacA(72.9%),CagA(52.1%),VacA+CagA(39.6%);30 OSAHS,VacA(33.3%),CagA(23.3%),VacA+CagA(16.7%).Conclusion:Our study supports the possible role of H.pylori in chronic tonsillitis.H.pylori maybe one of the risk factors of chronic tonsillitis.dd PCR had bettersensitivity and specificity compare to H.pylori serological and RT PCR.Feasible anti H.pylori treatment maybe used for H.pylori associated chronic tonsillitis.