Assessment and grading of mucosal inflammation in colonic diverticular disease

The aim of this study was to assess and grade the mucosal inflammatory infiltrate in different degrees of diverticular disease (DD) and to compare them with healthy matched controls.

Mucosal inflammation in colonic DD has never been investigated. In particular, it is unknown whether inflammation may be found in every degree of DD.

Thirty consecutive patients with a new endoscopic diagnosis of DD (10 with asymptomatic diverticulosis, 10 with symptomatic uncomplicated DD, and 10 with acute uncomplicated diverticulitis) and 10 healthy controls were studied.

A neutrophilic inflammatory infiltrate was found only in acute uncomplicated diverticulitis (overall score, 26). The mean lymphocytic cell density was significantly higher in symptomatic DD (median lymphocytic density, 7) and acute uncomplicated diverticulitis (median lymphocytic density, 11). Subdividing the patients according to different degrees of DD, we found higher lymphocytic cell density even in asymptomatic diverticulosis (median lymphocytic density, 6.5) than healthy controls (median lymphocytic density, 4; P<0.02).

We found an increased inflammatory infiltrate in DD according to the degree of the disease and higher than healthy controls. Moreover, also asymptomatic diverticulosis shows higher inflammatory cell density than controls.