We evaluated the quality control status of glycated hemoglobin A1c (HbA1c) and glycated albumin (GA) at The Japanese Study Group of Insulin Therapy for Childhood and Adolescent Diabetes. We used the absolute relative difference (ARD) between one centralized laboratory value and the values from four clinical samples at each Institute. The methods that each method used for the measurement of HbA1c and GA were investigated and we determined whether the measurement was conducted in-hospital. Additionally, for GA, the number of samples at each institution and the frequency of internal quality control by existing calibrators were investigated. HbA1c sample measurements were conducted in-hospital in 98 % of the cases and 86 % were measured using the HPLC method. For GA, 78 % of measurements were conducted in-hospital, and the frequency of quality control was 1.9 (0-6) times per month. The mean ARD of GA was 2.65 %, which was significantly higher than the mean ARD of HbA1c (1.91 %). The ARD of GA was higher in institutes with less frequent internal quality control and fewer samples. Both HbA1c and GA were well controlled in terms of accuracy, but it was considered important to ensure the frequency of internal quality control for GA measurement. The analysis of clinical specimens was useful for continuous external quality control.

We investigated the effect of blood collection tubes on HbA1c levels measured by off-site immunoassay (IA-HbA1c). The present study included a total of 34 patients who were treated at Kawanishi City Hospital, excluding those treated with variant hemoglobin. From 2012 to 2019, off-site IA-HbA1c levels were compared with HbA1c levels measured by an on-site HPLC assay (HPLC-HbA1c) using the same sample. At our hospital, a tube containing EDTA (EDTA tube) was initially used as the blood collection tube, and the HbA1c measured by both assays were almost the same. After changing the blood collection tube to a tube containing sodium fluoride (tube for glucose measurement) in September 2015, the IA-HbA1c levels became significantly lower than the HPLC-HbA1c levels. Thus, an EDTA tube, rather than a tube for glucose measurement, should be used as the blood collection tube for off-site IA-HbA1c measurement.

The patient was a 65-year-old man who had been diagnosed with diabetes 3 years previously. An examination revealed an HbA1c level of 10.6 %, which improved to approximately 6 % with diet and exercise therapy. The patient underwent surgery and received chemotherapy for his lung cancer, but mediastinal lymphadenopathy remained. Thus, pembrolizumab, an anti-programmed cell death-1 (PD-1) antibody, was administered. Two months later, steroids were administered for suspected bronchial asthma. The following day, he was admitted due to diabetic ketoacidosis. His anti-glutamic acid decarboxylase (GAD) antibody level was 9.7 U/mL. One month previously, his HbA1c, casual blood glucose, and blood C-peptide immunoreactivity were 6.7 %, 121 mg/dL, and 1.9 ng/mL, respectively. Serum collected prior to anti-PD-1 antibody administration was positive for anti-GAD, anti-thyroglobulin, and anti-thyroid peroxidase antibodies. In this patient with slowly progressive type 1 diabetes accompanied by Hashimoto's disease, the patient's diabetes was acutely exacerbated and thyrotoxicosis occurred around the same time after the administration of anti-PD-1 antibody. This case brings attention to the importance of the early diagnosis and treatment of diabetic ketoacidosis.

The patient was a 78-year-old female who had been treated for type 2 diabetes mellitus for 37 years. However, she was diagnosed with slowly progressive type 1 diabetes mellitus at 72 years old based on a GAD Ab (RIA) of 51,000 U/mL. At 78 years old, she experienced appetite loss, diarrhea, vomiting, and loss of consciousness. Diabetic ketoacidosis (DKA) was diagnosed based on a pH of 6.711, a plasma glucose level of 1636 mg/dL, and a urine ketone body positive test result. Injection of saline and insulin aspart improved DKA. Autoimmune polyglandular syndrome (APS) type 3 was diagnosed based on positive TPOAb, TgAb, and intrinsic factor antibody, along with pernicious anemia. Bloody diarrhea, colonoscopy, and a tissue examination confirmed the diagnosis of ulcerative colitis (UC). Only 31 cases of type 1 diabetes mellitus and UC have been reported in Japan. Among these cases, 10 match the APS type 3 criteria. Our case exhibited HLA-DR4 and DR9; the former might be associated with APS type 3 and the latter with other autoimmune diseases and elderly-onset UC. We advocate paying close attention to cases of DKA among elderly type 1 diabetes patients with UC.

A 92-year-old man was admitted to our hospital because of disturbance of consciousness due to hypoglycemia associated with hyperinsulinemia. Contrast-enhanced computed tomography (CT) identified an early-staining tumor 14 mm in diameter in the pancreas tail. Insulinoma was clinically diagnosed. Since the patient refused surgical treatment, diazoxide at 250 mg/day was initiated, followed by a reduction to a dose of 75 mg/day. Thereafter, the blood glucose levels stabilized. For up to two years, the patient has been free from any episodes of hypoglycemia without an obvious increase in the tumor size. Thus, diazoxide seems to be a suitable treatment for elderly patients with insulinoma to maintain a good quality of life for a long period without episodes of hypoglycemia.

Anti-glutamic acid decarboxylase (anti-GAD) antibodies were detected in two diabetic patients after they underwent treatment with intravenous immunoglobulin (IVIg). Case 1: A 76-year-old man was given IVIg to treat chronic inflammatory demyelinating polyneuropathy (CIDP), and 11 days later, his anti-GAD antibody level was 32.4 U/mL. However, 471 days later, the level dropped to negative values. Following the second IVIg treatment, his anti-GAD antibody level increased to 11.4 U/mL after 11 days but became negative again 36 days later. Case 2: A 33-year-old man was given IVIg to treat Guillain-Barré syndrome, and his anti-GAD level was 32.4 U/mL on the third day following IVIg. However, 21 days later, the level had decreased to 8.5 U/mL. He was given IVIg again, but after 127 days, the level once more became negative. The anti-GAD antibody levels were measured using a commercial enzyme-linked immunosorbent assay. Our results indicate that the transient appearance of anti-GAD antibody was associated with IVIg. Therefore, we suggest that confirming whether patients were given IVIg prior to the classification of their diabetes is essential in clinical practice.

The status of medical care transition from adolescence to adulthood in patients with type 1 diabetes was evaluated through a questionnaire survey (response rate: 44.2 %) among the councilors of the Japanese Society for Pediatric Endocrinology. The highest number of patients with type 1 diabetes in their institution was between 0 and 19 (65.1 %). Among the patients, the number of patients older than 20 years of age was between 0 and 9 (83.3 %). In the previous 5 years, between 0 and 9 patients most frequently underwent a transition in health care from adolescence to adulthood (81.0 %). Graduation from high school was identified as the most common timepoint for transition (58.3 %). Among the participating institutions, 70.2 % had a department of internal medicine within the same institution and 71.4 % had a department of internal medicine within the same prefecture, which was suitable for transitional medical care; 85.7 % of the patients agreed to transitional medical care, while 14.3 % of patients did not. The main reason for the refusal of transition was the perception that change was unnecessary, and that pediatricians were prepared to continue to provide medical care, except for the treatment of diabetic complications. Thus, pediatric patients with type 1 diabetes should receive education on the importance of transitional medical care from adolescence to adulthood.