Final answer:
Based on the absence of an organic cause for the symptoms and the history of surgery scars without a definitive medical issue, the most likely diagnosis is Somatization Disorder, a condition where psychological distress presents as physical pain.
Step-by-step explanation:
A 30-year-old nurse complains of severe abdominal pain, with a history of similar episodes in the past and no organic cause found on examination, but with abdominal scars from repeated surgeries. This scenario suggests a diagnosis of Somatization Disorder, characterized by the occurrence of physical symptoms that are not explained by any known medical condition or substance use. In contrast, conditions such as Irritable Bowel Syndrome, Crohn's Disease, or Endometriosis usually have identifiable physiological or anatomical abnormalities that can explain the symptoms. Somatization Disorder involves a complex interaction between psychological and physical factors, where the individual's psychological distress manifests as physical symptoms.