Pathology-based evidence and literature review of an association between adenovirus infection and appendicitis in children and adults

Abstract

The main cause of appendicitis is that the opening of the appendix becomes blocked. Some blockages are caused by fecalith, and others are caused by swelling of nearby lymph nodes. Appendiceal obstruction can lead to poor circulation, bacterial growth, and tissue hypoxia, leading to appendiceal necrosis, peritonitis, sepsis, and even death. In addition to fecalith, some reports have observed an association between appendicitis and lymphoid hyperplasia, which may be caused by infections such as adenovirus, but direct evidence is lacking. A total of 360 patients with appendicitis: 240 adult patients, 120 patients <18 years and 40 control individuals without appendicitis for a retrospective study. Pathological tissues from appendectomies were processed into formalin-fixed paraffin-embedded (FFPE) slices. Adenovirus immunohistochemistry (IHC) and quantitative polymerase chain reaction (qPCR) were analyzed to determine whether adenovirus was present in appendicitis tissue. The positive rate of IHC detection (25.8%) and qPCR analysis (35.0%) in pediatric patients was higher with p<0.05, which was statistically significant. The positive rate of IHC detection (10.8%) and qPCR analysis(14.2%) in adults was low with p≥0.05, which was not statistically significant. Control subjects were negative for both IHC and qPCR analysis. Our study directly demonstrates the relationship between adenovirus infection and appendicitis using retrospective pathological evidence from IHC analysis and qPCR detection.qPCR is more sensitive and reliable than IHC for the diagnosis of adenovirus in appendicitis, showing higher sensitivity than IHC. Adenovirus infection is more closely associated with appendicitis in children than in adults.