[Orange oily anal leakage: a new entity linked to dietary changes].

Introduction: Information is accumulating on exceptional cases of oily orange anal leakage, probably caused by certain foods and their form of consumption. The leakage is usually inadvertent and is worrisome for patients.

Method: Clinical data was gathered on a case series presenting with massive and inadvertent orange oily anal leakage, without sphincter sensation, causing the patients to feel alarmed. This condition usually occurs after eating fish, especially Japanese cuisine.

Results: Eleven patients were included (four women and seven men). The mean age was 47.3 years. Colonoscopy had previously been performed in four patients, with normal results. The symptoms, described as keriorrhea, were probably produced by accumulation of indigestible "wax esters", es Mero present in some oily fish, recently incorporated in raw fish dishes (sashimi) or as Japanese Mero sea bass. These oils, which cannot be absorbed or digested, accumulate in the rectum and may also filter spontaneously and induce toxin-related sphincter dysfunction. The same symptoms are sometimes produced after consumption of cooked versions of these species. The diagnosis is given by clinical data, prior ingestion of these types of fish and the self-limiting nature of the symptoms, without the need for further investigations.

Conclusion: We describe a case series of a recently described entity associated with dietary changes. This entity is benign and self-limiting. Clinicians should be familiar with the symptoms to inform patients correctly and avoid unnecessary laboratory studies.