Changing clinical and roentgenographic patterns of necrotizing enterocolitis.

Necrotizing enterocolitis (NEC) occasionally deviates from the classical presentation of the disease. Small bowel dilatation and pneumatosis are frequently present prior to the actual onset of the clinical presentation. Pneumatosis intestinalis, an important diagnostic sign of NEC, is quite variable; it may be present, persist, worsen, or disappear; or at times it may not be present at all. A severe complication of necrotizing enterocolitis is perforation which in 50 percent of the cases presented without obvious free intra-abdominal air. Accumulation of fluid in the abdomen is stressed as strong evidence for perforation and a strong indication for surgery. The varying features indicate that NEC has a clinical spectrum that extends from benign to severe, and recognition of all these variations will lead to better diagnosis and to a better understanding of the disease. The clinical and roentgenologic variations make classification difficult but the variety most likely represents the combination of a great number of susceptible children and a greater recognition of the disease.