Familial partial lipodystrophy (FPLD) is a rare genetic disorder leading to adipose tissue deficiency/redistribution and metabolic dysregulation with insulin resistance, diabetes mellitus, and dyslipidemia. Coincidence of FPLD and autoantibody-positive type 1 diabetes has not been published yet. We identified a female patient with the initial diagnosis of autoantibody-positive type 1 diabetes who developed severe insulin resistance with daily insulin doses up to 300 IU/d, acanthosis nigricans, polycystic ovary syndrome, hyperphagia, myalgia, and dyslipidemia. Since her phenotype was suspicious for FPLD, genetic testing was initiated. It revealed a heterozygous missense variant at hot spot codon c.1444 withinA/C (. Insulin resistance and hyperphagia improved during treatment with the glucagon-like peptide 1-receptor agonist semaglutide in addition to insulin therapy. Thus, we report about a patient with FPLD2 and concomitant type 1 diabetes. This case demonstrates that coincidence of these 2 severe metabolic dysregulations challenges diagnosis, management, and treatment but demands awareness in our health care system for rare endocrine diseases to improve quality of care.