TBIRS is most observed in young women of African origin.A history of autoimmune disorder is common, usually systemic lupus erythematosus or mixed connective tissue disease.TBIRS can also occur in association with type 1 diabetes or as a paraneoplastic manifestation (e.g. lymphoproliferative disorders).TBIRS is a very rare disease, with only about a hundred cases.We report a new case observed in France in a young woman.A 23-yr-old female of Guinean origin, with no personal or family medical history, presented with polydipsia, secondary amenorrhea, and weight loss (15 % of body weight; body mass index 24.1 kg/m2).Phys. examination revealed severe acanthosis nigricans on the neck, axillae, and thighs.Extremely high doses of insulin (up to 500 units/h) for several days were required to maintain blood glucose level < 200 mg/dL and normalize ketones level.The following treatment regimen was used: human ultraconcd. insulin to facilitate administration of very large doses, dexamethasone 40 mg/d for 4 days, 3 times at one-month intervals, and one cycle of rituximab (two infusions at fortnightly interval at the dose of 750 mg/m2).Insulin doses increased following glucocorticoid therapy but decreased in a few days allowing infusion to be discontinued.Metformin and glucagon-like peptide 1 (GLP-1)-receptor agonist were used in association with insulin therapy to decrease insulin resistance.Over a6-mo period, we observed a decrease in insulin doses until normalization of blood glucose levels, as well as remission of acanthosis nigricans and signs of hyperandrogenism.The time course of the interstitial glucose time-in-range (70-180 mg/dL), monitored with a FreeStyle device (Abbott diabetes care Inc., USA), during follow-up, and the treat ment regimen are presented in the Fig. 1.In this case, we decided not to use cyclophosphamide because of the patient's young age and the risk of toxicity (mainly gonadal).Some elements remain unexplained, such as the discrepancy be tween high doses of insulin and absence of hypokalemia as well as significant ketosis without symptoms or acidosis.