The paucity of literature and textbook references on acute mesenteric lymphadenitis has been an incentive to me to review all cases of the disease which had been hospitalized in the Albany Hospital during the years from January, 1940, to August, 1956, inclusive. One hundred ninety-eight cases were analyzed. Every surgeon has operated upon cases which apparently gave a sign-symptom complex of acute appendicitis, and yet there was found at operation a normal appendix but with enlargement of the mesenteric lymph nodes, most especially those nodes distributed about the terminal ileum and the appendicocecal junction. The patient recovers, and recovery is attributed to the appendectomy. Can one evaluate these cases to such a degree that in many cases surgical procedures are unnecessary? And is one able to define a sign-symptom complex which might very well encompass the diagnosis of primary acute mesenteric adenitis? Or are the symptoms and signs so bizarre