Nonoperative management of the ultrasonically evaluated appendiceal mass.

Forty patients with an ultrasonically evaluated appendiceal mass were studied. Abscesses were diagnosed in 31 patients (78%). Seventeen patients had an ultrasonically guided percutaneous drainage performed, and all but one patient had resolution of symptoms without further treatment or complications. Fourteen patients were treated conservatively without drainage, and 12 had resolution of symptoms without interference. Ultrasonograms in the remaining nine patients (22%) revealed phlegmonous inflammation only, and all recovered without treatment. The three patients considered failures had surgery because of intestinal obstruction or suspected but unverified perforation. Three patients (8.5%) had recurrent appendicitis within 5 months after the initial attack. Diagnostic errors delayed proper therapy for 1 month in a patient with a cecal carcinoma and for 5 months in a patient with Crohn's disease. Late sequelae were observed in four patients, three of whom had surgery. Nonoperative treatment and if possible ultrasonically guided percutaneous drainage of verified abscesses are safe procedures with few complications and late sequelae. However, diligent in-hospital observation and close follow-up are mandatory.