Mesenteric panniculitis is a non-specific inflammation of the mesenteric adipose tissue, with varying degrees of fibrosis and fat necrosis. It can be associated with varying diseases and conditions, such as autoimmune disease and cancer. Many doctors are not familiar with this disease or do not know how to interpret the signs and symptoms. Here, we describe three patients illustrating the variety of clinical course, diagnostics, prognosis and treatment. A 44-year-old woman suffering from episodic abdominal pain was diagnosed with uncomplicated mesenteric panniculitis. The disease was stable while maintaining a conservative approach. In a 43-year-old woman, mesenteric panniculitis was complicated by autoimmune haemolytic anaemia. After treatment with corticosteroids, she made a full recovery from both disorders. Finally, a 73-year-old man was diagnosed with mesenteric panniculitis and auto-immune haemolytic anaemia, which both appeared to be consequences of an angioimmunoblastic T-cell lymphoma.