IntroductionImmune checkpoint inhibitors are a promising class of anticancer drugs. The clinical benefits afforded by immune checkpoint inhibitors can be accompanied by immune-related adverse events that affect multiple organs, and endocrine immune-related adverse events include thyroiditis and hypophysitis. Hypophysitis is less frequent and has a less severe clinical presentation in patients treated with other immune checkpoint inhibitors, such as nivolumab, pembrolizumab, and atezolizumab, than in those treated with ipilimumab. However, studies have described isolated adrenocorticotropic hormone deficiency cases associated with nivolumab, pembrolizumab, and atezolizumab therapy, most of which occurred during the course of immune checkpoint inhibitor therapy. We report a rare case of patient with isolated adrenocorticotropic hormone deficiency that occurred after nivolumab therapy.Case presentationA 69-year-old Japanese woman with advanced lung adenocarcinoma developed painless thyroiditis with transient elevations of serum thyroid hormones during 3 months of cancer treatment with nivolumab and began thyroid hormone replacement therapy for subsequent primary hypothyroidism. Four months after nivolumab therapy was discontinued, she developed isolated adrenocorticotropic hormone deficiency; corticosteroid replacement therapy relieved her secondary adrenal insufficiency symptoms, such as anorexia and fatigue. Human leukocyte antigen typing revealed the presence of DRB1*04:05-DQB1*04:01-DQA1*03:03 and DRB1*09:01-DQB1*03:03-DQA1*03:02 haplotypes, which increase susceptibility to autoimmune polyendocrine syndrome associated with thyroid and pituitary disorders in the Japanese population.ConclusionsOur patient developed thyroiditis during cancer treatment with nivolumab and subsequently exhibited isolated adrenocorticotropic hormone deficiency 4 months after discontinuing the drug. Administration of nivolumab in combination with a genetic predisposition to polyglandular autoimmunity probably caused both the thyroiditis and hypophysitis, resulting in primary hypothyroidism and isolated adrenocorticotropic hormone deficiency, respectively, in our patient. The present case highlights the need for physicians to be aware that endocrine immune-related adverse events, including hypophysitis, can occur more than several months after discontinuing a drug.

A 70-year-old man with insulinoma-associated antigen-2 autoantibodies developed diabetes mellitus (DM) without ketoacidosis after starting nivolumab to treat advanced gastric cancer. He subsequently exhibited preserved insulin-secretion capacity for over one year. Immune checkpoint inhibitors (ICIs) infrequently cause type 1 DM associated with the rapid loss of insulin secretion and ketoacidosis as an immune-related adverse event. ICIs may also cause non-insulin-dependent DM by inducing insulin resistance if there is islet autoantibody-related latent beta-cell dysfunction. The present case highlights the importance of testing blood glucose levels regularly to diagnose DM in patients treated with ICIs, even if they do not have diabetic ketoacidosis.

Aims/Introduction Diabetes is associated with poor clinical outcomes of coronavirus disease 2019 (COVID‐19). However, the impact of newly diagnosed diabetes on prognosis has not been clarified. The objective of this study was to show the features and outcome of COVID‐19 patients with newly diagnosed diabetes in Japan. Materials and Methods We retrospectively analyzed 62 patients with diabetes hospitalized for COVID‐19 between 1 April and 18 August 2021 at the National Center for Global Health and Medicine in Tokyo, Japan. We evaluated the worst severity of COVID‐19 and plasma blood glucose levels in patients with newly diagnosed diabetes or pre‐existing diabetes. Results This study included 62 confirmed COVID‐19 patients with diabetes, including 19 (30.6%) patients with newly diagnosed diabetes and 43 (69.4%) patients with pre‐existing diabetes. Patients with newly diagnosed diabetes significantly progressed to a critical condition more frequently during hospitalization than patients with pre‐existing diabetes (52.6% vs 20.9%, P = 0.018). In addition, patients with newly diagnosed diabetes had significantly higher average plasma blood glucose levels for the first 3 days after admission than those with pre‐existing diabetes. Conclusions Our study suggests that the proportion of COVID‐19 patients who are newly diagnosed with diabetes is high, and they have an increased risk of developing severe disease than those with pre‐existing diabetes. It might be advisable that at the point of COVID‐19 diagnosis, blood glucose and glycated hemoglobin levels be assessed in all patients.

A 35-year-old Japanese woman with no history of hypertension developed hypertension 5 days after normal delivery. Endocrinological and radiological examinations indicated primary aldosteronism (PA) and a 1.4cm left adrenal tumor. The patient underwent laparoscopic adrenalectomy, and a diagnosis of aldosteroneproducing adenoma was confirmed immunohistochemically. Her plasma aldosterone concentration and blood pressure normalized. Cases of PA presenting with hypertension in the postpartum period have been reported. This case suggests that PA should be considered in women with postpartum hypertension, especially in those with blood pressure that suddenly increases shortly after delivery, even if they were normotensive before and throughout pregnancy.