May Be Caused by

 Common

Carcinoma of colon

Carcinoma of kidney

Carcinoma of pancreas

Gastric cancer

Gastrostomy

Pancreatitis

Perforated peptic ulcer

Postoperative state

Retained sponge

Trauma with colonic perforation

Trauma with duodenal perforation

Trauma with gastric perforation

 Uncommon

Actinomycosis

Amebic colitis

Biliary tract perforation

Crohn disease

Lung cancer

Marginal ulcer

Perforated colonic diverticulum

Perforated duodenal diverticulum

Tuberculosis

Typhoid fever