Background: The programmed cell death 1 (PD-1) inhibitor pembrolizumab is a promising agent for treatment of several different malignancies, but as with all immunotherapy there is a potential risk of immune-related adverse events. Adrenocorticotropic hormone (ACTH) deficiency and hypophysitis have been reported in patients treated with a different PD-1 inhibitor, nivolumab. However, clinical characteristics of these side effects associated with pembrolizumab have yet to be described in detail. Case presentation: An 85-year-old Japanese woman was diagnosed with advanced squamous cell lung cancer. The patient was treated with 200 mg pembrolizumab every three weeks as first-line therapy. Routine examination including thyroid function, complete blood count, serum cortisol and sodium levels before each pembrolizumab infusion had shown no significant changes up to the eighth cycle. However, 8 days after the eighth cycle of singleagent pembrolizumab, she presented with rapidly worsening general fatigue and appetite loss over two days. Laboratory data revealed a low serum cortisol level (0.92 μg/dL) with inappropriately low ACTH (8.3 pg/mL), hyponatremia (122 mmol/L) and hypoglycemia (68 mg/dL). Standard-dose short ACTH testing showed an unsatisfactory cortisol response, indicating adrenal insufficiency. Pituitary magnetic resonance imaging showed diffuse substantial gadolinium enhancement, T2 hyperintensity, loss of pituitary bright spot, but no pituitary enlargement. Serum cortisol and ACTH levels were low throughout the day, and urinary free cortisol excretion fell below the lower normal limit. There was no ACTH and cortisol response in the corticotropin-releasing hormone test, despite significant responses of other anterior pituitary hormones to their corresponding challenge tests. Thus, isolated ACTH deficiency was diagnosed, and hypophysitis was suspected as the etiology. After administration of 15 mg/day hydrocortisone, the patient's debilitation, hyponatremia, and hypoglycemia swiftly disappeared. Conclusion: This is a case of isolated ACTH deficiency possibly due to hypophysitis in a patient with advanced lung cancer, in whom recent routine examinations had shown unremarkable results. We therefore conclude that isolated ACTH deficiency can suddenly arise during pembrolizumab monotherapy, albeit probably only rarely. Caution should be exercised to make sure that adrenal insufficiency is recognized immediately in order to achieve swift recovery by steroid replacement.

Hyponatremia associated with low-dose trimethoprim in patients on concomitant systemic corticosteroid therapy has rarely been reported. Here, we describe a 57-year-old woman with a history of diabetes mellitus and hypertension treated with telmisartan, who presented with progressive visual impairment of the left eye due to anti-aquaporin-4 antibody-positive optic neuritis. The patient received pulsed intravenous methylprednisolone followed by oral prednisolone at 30 mg/day and trimethoprim–sulfamethoxazole prophylaxis (160 mg and 800 mg daily). Her serum sodium level steadily decreased, and the potassium level was slightly elevated despite well-preserved renal function. This state persisted even after telmisartan discontinuation. In addition to hypotonic hyponatremia (125 mEq/L) with natriuresis, hyperkalemic renal tubular acidosis was diagnosed based on normal anion gap metabolic acidosis and hyperkalemia with low urinary potassium excretion. After trimethoprim–sulfamethoxazole cessation, electrolytes and acid–base imbalances swiftly recovered. We can conclude that caution must be exercised when treating such patients, because even low-dose trimethoprim may cause hyponatremia concomitant with hyperkalemic renal tubular acidosis, despite the mineralocorticoid effects of systemic corticosteroids.

Glucagon-like peptide-1 receptor agonist (GLP-1RA) and sodium-dependent glucose transporter 2 inhibitor (SGLT2i), in addition to lowering glucose, have pleiotropic effects on the heart, kidneys, and liver. These drugs have thus come into widespread use for treating type 2 diabetes (T2DM). However, mechanistic comparisons and effects of combining these drugs have not been adequately studied. Employing diet-induced obese (DIO) mice and db/db mice as models of the early and advanced stages of T2DM, we evaluated effects of single or combined use of liraglutide (a GLP-1RA) and ipragliflozin (a SGLT2i). Treatments with liraglutide and/or ipragliflozin for 28 days improved glycemic control and reduced hepatic lipid accumulation similarly in DIO mice. In contrast, in db/db mice, despite similar favorable effects on fatty liver, liraglutide exerted no beneficial effects on glycemic control. Improved glycemic control in db/db mice treated with ipragliflozin was accompanied by increased pancreatic β-cell area and insulin content, both of which tended to rise further when ipragliflozin was combined with liraglutide. Our data suggest that liraglutide is more efficient at an earlier stage and ipragliflozin can be effective in both stages. In addition, their combined use is a potential option for treating advanced stage diabetes with fatty liver disease.

The aim of this study was to investigate factors associated with sarcopenia among elderly patients with poorly controlled diabetes mellitus (DM). We retrospectively analyzed 41 patients with type 2 DM, aged ≥65 years who required diabetes education hospitalization. Patients were classified into two groups according to the presence or absence of a weakened hand grip, and clinical characteristics were compared. Patients with a weakened hand grip (n = 21) scored worse on a mini-mental state examination (24.3 vs. 26.5, p = 0.04), showed a higher prevalence of diabetic peripheral neuropathy (76% vs. 40%, p = 0.03), and had a higher serum phosphorus concentration (3.8 vs. 3.3 mg/dL, p < 0.01) compared to those without a weakened hand grip (n = 20). The serum phosphorus concentration was inversely correlated to hand grip strength (r = −0.501, p < 0.001) among the total of 41 patients. This inverse association was also confirmed after adjusting the effects of estimated glomerular filtration rate, age, and glycated hemoglobin. Thus, cognitive impairment, diabetic peripheral neuropathy, and high serum phosphorus concentrations are associated with hand grip weakness in elderly patients with type 2 DM.

The standard six-month tuberculosis (TB) treatment comprises an intensive phase lasting two months, followed by a continuation phase lasting four months. Meanwhile, the nine-month regimen, which has a prolonged continuation phase, is indicated for patients with complicated diabetes mellitus (DM) because of their poor response to treatment. A 61-yearold Japanese man with poorly controlled DM for five years presented with bilateral scrotal swelling noticed two weeks ago. He had a history of pleuritis, pericarditis, and peritonitis two years ago. These symptoms led to the diagnosis of culture-negative extrapulmonary TB. He received the nine-month chemotherapy regimen (isoniazid, rifampin, pyrazinamide, and ethambutol for two months, followed by isoniazid and rifampin for seven months), and his symptoms significantly improved. The swollen scrotum was accompanied by mild tenderness and pus discharge from a fistula. Imaging study revealed bilaterally diffusely enlarged epididymis. However, the acid-fast bacilli smear and culture and polymerase chain reaction using urine and pus discharge tested negative. Bilateral epididymectomy was performed. Although the acid-fast bacilli smear was negative, the pathology demonstrated granuloma formation and acid-fast bacilli tissue culture confirmed multi-drug resistant Mycobacterium tuberculosis. The optimal treatment regimen and duration for extrapulmonary TB with unknown drug susceptibility are debatable. The nine-month regimen can be insufficient in some cases. Thus, detailed follow-up is essential, and TB relapse should be thoroughly monitored.