The current status of oral frailty based on the Japan Dental Association self-check chart and the relationships between oral frailty and patient background were investigated in 260 patients with type 2 diabetes over 45 years old (female: 40 %, age: 70±11 years old). A high risk of oral frailty was observed in 93 subjects (36 %), and more than half of the subjects were ≥75 years old. The clinical background significantly associated with a high risk of oral frailty was the age of the patient (odds ratio = 1.05, 95 % confidence interval=1.01-1.08, P=0.01) according to multivariate logistic regression. In another multivariate model, the patient age and serum albumin level (P=0.02) were significant explanatory factors for the high risk of oral frailty, and the presence of peripheral neuropathy also showed a tendency to be related to oral frailty (P=0.05). In a receiver operating characteristic curve, the cutoff value for age at high risk for oral frailty was calculated to be 74 years old. Proactive assessments and intervention for oral frailty are necessary in elderly patients, patients with malnutrition, or those with diabetic peripheral neuropathy.

A 92-year-old woman who had been diagnosed with diabetes three years previously and was taking canagliflozin for three months was admitted to our hospital because of fever and decreased blood pressure. Her blood pressure was 83/48 mmHg, and a laboratory examination showed a urinary tract infection, positive CRP, and renal dysfunction. Escherichia coli was detected in the urine and blood cultures. Abdominal computed tomography (CT) revealed air bubbles in the bladder wall. Based on these findings, the patient was diagnosed with septic shock accompanied by emphysematous cystitis. Her blood glucose level was 186 mg/dL and her HbA1c level was 6.5 %, indicating no worsening of glycemic control. The patient's condition improved with urethral drainage, fluid infusion, norepinephrine, and antibiotics. Emphysematous cystitis often occurs in elderly women with poorly controlled diabetes. However, in recent years, the increased use of SGLT2 inhibitors has been reported to be associated with emphysematous cystitis. Even elderly people with good blood glucose control may develop emphysematous cystitis when taking SGLT2 inhibitors.

A 47-year-old man with type 2 diabetes mellitus, which was untreated for 10 years, was admitted to our hospital with diabetic ketoacidosis (HbA1c 16.5 %), which improved to HbA1c 7.1 % within 2 months after acute treatment and intensive insulin therapy. At the same time, he became aware of numbness in his upper and lower limbs and lightheadedness, which gradually worsened, and orthostatic hypotension also appeared. Nerve conduction studies revealed polyneuropathy with a sensory nerve predominance. Although the symptoms were not typical, we clinically diagnosed the patient with treatment-induced neuropathy of diabetes (TIND). A sural nerve biopsy revealed a decreased density of large and small myelinated fibers, macrophage infiltration, and elevated CSF protein, which suggested an immune-mediated and inflammatory mechanism. Therefore, we administered intravenous immunoglobulin (IVIg) therapy. As a result, the superficial sensory disturbance of the upper extremities and orthostatic hypotension improved. We report an interesting case in which neurological symptoms in a patient with TIND improved after IVIg treatment.