Pembrolizumab-Induced Diabetic Ketoacidosis: A Review of Critical Care Case

Autoimmune diabetes from pembrolizumab: A case report and review of literature

BACKGROUND

Immunotherapy, specifically the use of checkpoint inhibitors such as pembrolizumab, has become an important tool in personalized cancer therapy. These inhibitors target proteins on T-cells that regulate the immune response against tumor cells. Pembrolizumab, which targets the programmed cell death 1 receptor on T-cells, has been approved for the treatment of metastatic melanoma and non-small cell lung cancer. However, it can also lead to immune-related side effects, including pneumonitis, colitis, thyroid abnormalities, and rare cases of type 1 diabetes.

CASE SUMMARY

The case presented involves an adult patient in 30s with breast cancer who developed hyperglycemia after receiving pembrolizumab treatment. The patient was diagnosed with diabetic ketoacidosis and further investigations were performed to evaluate for new-onset type 1 diabetes. The patient had a history of hypothyroidism and a family history of breast cancer. Treatment for diabetic ketoacidosis was initiated, and the patient was discharged for close follow-up with an endocrinologist.

CONCLUSION

This literature review highlights the occurrence of diabetic ketoacidosis and new-onset type 1 diabetes in patients receiving pembrolizumab treatment for different types of cancer. Overall, the article emphasizes the therapeutic benefits of immunotherapy in cancer treatment, particularly pembrolizumab, while also highlighting the potential side effect of immune-related diabetes that can occur in a small percentage of patients. Here we present a case where pembrolizumab lead to development of diabetes after a few cycles highlighting one of the rare yet a serious toxicity of the drug.

A Case of Pembrolizumab-Induced Diabetic Ketoacidosis and Hyperthyroidism in a Patient With Recurrent Esophageal Adenocarcinoma

Immune checkpoint inhibitors (ICI) such as program cell death protein 1 (PD-1) inhibitors are widely used for the treatment of patients with recurrent, locally advanced or metastatic, gastric or gastroesophageal (GE) junction adenocarcinoma. Immune-related adverse events (irAE) such as endocrinopathies have been reported after patients received ICI. We report a case of pembrolizumab-induced hyperthyroidism and type 1 diabetes mellitus (DM1) presenting with diabetic ketoacidosis (DKA). A 53-year-old African American male with no history of diabetes or hyperthyroidism was treated with two cycles of pembrolizumab for recurrent GE junction adenocarcinoma after which he was admitted with hyperthyroidism (thyroid stimulating hormone [TSH] 0.070mIU/L, free thyroxine 1.85mIU/L) and DKA (pH 7.06, glucose 583 mg/dL, beta-hydroxybutyrate 8.63 mmol/L, anion gap 27 meq/L). The patient was treated with intravenous insulin and aggressively hydrated. Given the lack of other precipitating factors for the two endocrinopathies, it was determined that the most likely etiology was recent treatment with pembrolizumab (a PD-1 inhibitor). In our case, pembrolizumab monotherapy developed two irAE (hyperthyroidism and DKA), which is unique as most combined immunotherapy regimens are associated with the development of multiple endocrinopathies. Our case emphasizes the importance of baseline monitoring of thyroid function and blood glucose prior to the start of ICI to monitor and evaluate patients with immune-related adverse events, including endocrinopathies.

PD-1 inhibitor-associated type 1 diabetes: A case report and systematic review

Objective

This study aimed to summarize the clinical characteristics of programmed death receptor 1 (PD-1) inhibitor-associated type 1 diabetes so as to improve the ability of clinicians to correctly diagnose and treat it.

Methods

We reported a case of a 70-year-old woman with gastric cancer who developed hyperosmolar hyperglycemic coma during camrelizumab (a PD-1 inhibitor) treatment and was diagnosed with PD-1 inhibitor-associated type 1 diabetes. We conducted a systematic review of 74 case reports of type 1 diabetes associated with PD-1 inhibitor therapy published before June 2022.

Results

The patient developed type 1 diabetes with hyperosmolar hyperglycemic coma after receiving camrelizumab chemotherapy for 6 months (9 cycles). We searched 69 English articles comprising 75 patients, all of whom had been treated with a PD-1 inhibitor (nivolumab or pembrolizumab) and progressed to diabetes after an average of 6.11 (1–28) cycles. Nivolumab combined with ipilimumab (a cytotoxic T lymphocyte-associated protein 4 inhibitor) had the shortest onset (4.47 cycles on average). A total of 76% (57/75) of patients developed diabetic ketoacidosis (DKA) at onset, and 50.67% (38/75) of patients had C-peptide <0.1 ng/mL. Most of the patients were tested for insulin autoantibodies, with a positive rate of 33.33% (23/69); of these, 86.96% (20/23) were tested for glutamate decarboxylase antibody and 46.67% (35/75) were tested for human leukocyte antigen (HLA). HLA-DR4 was the most common type.

Conclusions

The progression of type 1 diabetes induced by PD-1 inhibitors is relatively rapid. Islet failure often occurs when detected, seriously endangering patients' lives. Patients treated with PD-1 inhibitors should closely monitor their plasma glucose level during treatment to detect, diagnose, and treat diabetes on time.