RESUMEN
INTRODUCTION: Bisalbuminemias consist in rare qualitative modifications of several aspects in the albumin pattern. Bisalbuminemias, most of which are not pathological, can be observed using capillary electrophoresis. CASE REPORTS: We report a case of hereditary bisalbuminemia diagnosed by chance while exploring chronic unexplained hypereosinophilia in a 42-year-old patient. The patient's normal lipid profile, the lack of an antibiotic treatment or pancreatic pathology, and the persistence of the bisalbuminemia after one month, suggested a diagnosis of genetic bisalbuminemia. In light of other such cases, we review the main causes of bisalbuminemia, both genetic and acquired. CONCLUSION: The diagnosis of genetic bisalbuminemia is made by first eliminating the usual acquired etiologies: analytical or drug interference, acute pancreatitis and binding of immunoglobulins. Then, after having checked the lipemic index, reviewed the patient's medical history, comorbidities, and treatments, repeating the electrophoresis will help identify the cause of the bisalbuminemia.