Sintilimab-related diabetes mellitus and psoriasis: A case report and literature review

RATIONALE: With the popularity of ICIs in different oncology treatments, immune-related adverse events have raised concerns, mostly occurring in skin and endocrine gland injury. This disease involves different organ systems and presents with a variety of clinical manifestations. Most patients with immune checkpoint inhibitor-induced type 1 diabetes are reported to have no combination of autoimmune disease. We report a case of Sintilimab-related diabetes mellitus and psoriasis. PATIENT CONCERNS: We report a case of a 65-year-old female with Sintilimab-related diabetes mellitus and psoriasis. DIAGNOSIS: The patient treated with anti-programmed cell death protein 1 (Sintilimab) for 4 cycles. The patient presented with inexplicable bouts of nausea and vomiting, accompanied by chest discomfort and a feeling of breathlessness, prompting their admission to the local hospital. The initial assessment upon admission revealed an abrupt elevation in blood glucose levels, alongside normal ketone levels, lactic acidosis, and hyperuricemia. A comprehensive regimen was provided to regulate glucose levels and address the symptoms, resulting in notable improvement and subsequent discharge. Regrettably, the patient’s personal decision to discontinue medication for a single day led to the emergence of acute ketoacidosis, coupled with a recurrence of psoriasis vulgaris. Consequently, readmission became necessary. Based on the patient’s medical history and diabetes antibody testing, the diagnosis of immune checkpoint inhibitor induced diabetes mellitus has been confidently established. INTERVENTIONS: The patient ceased treatment with Sintilimab and was initiated on insulin therapy for glycemic control, alongside symptomatic management for psoriasis. Upon stabilization of the condition, long-term administration of exogenous insulin was implemented as a substitute treatment. OUTCOME: Outside of the hospital, insulin therapy effectively maintained stable blood glucose levels, and there were no further episodes of psoriasis flare-ups. LESSON: The clinical manifestations of immune checkpoint inhibitor induced diabetes mellitus are variable, and in this case the patient presented with unique primary symptoms. Therefore, it is crucial to accumulate relevant cases, understand the different clinical presentations and identify the underlying mechanisms of the disease. This will provide further evidence for early therapeutic intervention in similar patients in the future.