Neurogenic appendicopathy: an underestimated disease-systematic review of the literature.

PURPOSE: Appendectomy is one of the most frequently performed surgeries worldwide, but neurogenic appendicopathy (NA) remains a poorly understood disease with controversial clinical management. The aim of this review was to obtain a clear definition of the disease and summarize its management.

METHODS: We performed a systematic review of the literature on NA in PubMed, EMBASE, Web of Science, and Cochrane databases from inception to 19/01/2021 according to PRISMA statement standards. Eligibility criteria were original articles examining histopathology, clinical management, and/or follow-up of patients with NA. The literature review is complemented by a clinical case.

RESULTS: In 40 articles, the estimated incidence of NA among appendectomies performed in patients with a suspicion of acute appendicitis (AA) was 10.4% (N = 740, range 1.8-32%). NA more frequently causes recurrent and longer lasting pain compared to AA; however, these diseases are usually not clinically or radiologically distinguishable. Based on our analysis, NA is defined as the presence of three criteria: (1) clinical presentation of AA, (2) absence of acute inflammation on histopathology, and (3) presence of S-100-positive spindle cells or proliferation of Schwann cells. Laparoscopic appendectomy has been shown to be a safe and successful treatment.

CONCLUSIONS: NA is a poorly known disease, which may clinically appear as AA but is often related to recurrent and longer lasting abdominal pain. Patients with NA may suffer for years before diagnosis. In cases of typical symptoms, appendectomy should be performed even in cases of macroscopically and radiologically normal-appearing appendices with normal laboratory results.