Developing a Clear and New Definition of Non-specific Abdominal Pain for the Identification of Rare Diseases

Non-specific abdominal pain (NSAP) represents a diagnostic challenge that may include various rare diseases requiring early identification. If NSAP can be clearly defined, it may enable the early diagnosis of such rare diseases. This study aimed to develop a definition of NSAP based on the characteristics of diagnoses related to abdominal pain and on the backgrounds of undiagnosed patients in our previous study, as well as to provide recommendations. Data concerning patients with undiagnosed abdominal pain were analyzed to determine appropriate diagnostic criteria and timeframes for the NSAP definition. Based on this analysis, we propose the following definition of NSAP: "Abdominal pain that remains undiagnosed for ≥7 days after onset, despite undergoing abdominal computed tomography or ultrasonography, blood tests, and a general qualitative urine test. The abdominal pain may be persistent or intermittent and recur for ≥7 days. The duration and interval of intermittent pain are not considered." This proposed definition of NSAP may aid in identifying patients with rare diseases that cause abdominal pain.