Type I/type III collagen ratio associated with diverticulitis of the colon in young patients.

BACKGROUND: The incidence of diverticulitis in young patients is rising, whereas the type I:III collagen ratio of the colon decreases with age. Perhaps a lower type I:III collagen ratio in younger patients may predispose these patients to the development of the disease.

METHOD: The purpose of this study was to evaluate the collagen content and type I:III collagen ratio in patients with diverticulitis versus a control group. Patients who underwent a colon resection were identified. Three groups of patients were created for analysis: those with diverticulitis aged <50 y, >50 y, and a control group. Tissue samples were stained with Sirius red/fast green and photographed. Photos analysis was performed to quantify the amount of type I collagen and type III collagen. The type I:III collagen ratio was calculated for each patient and compared.

RESULTS: The quantity of type I collagen and type III collagen was higher in patients with diverticulitis aged >50 y (P = 0.04 and P < 0.0001, respectively); however, the collagen ratio was greatest in those patients with diverticulitis aged <50 y (P = 0.01). Further analysis demonstrated a significant higher type I:III ratio in all patients aged less than 50 y compared with all patients aged over 50 y (P = 0.04).

CONCLUSIONS: Our study demonstrated that diverticulitis in the younger patient was not associated with a lower type I:III collagen ratio. It appears that the decrease in collagen ratio of the colon with age is associated with an increase in type III collagen deposition.