Syndrome of Inappropriate Antidiuretic Hormone Secretion Following Liver Transplantation

Cascading renal injury after brain death: Unveiling glycocalyx alteration and the potential protective role of tacrolimus

Brain death (BD) is a complex medical state that triggers systemic disturbances and a cascade of pathophysiological processes. This condition significantly impairs both kidney function and structural integrity, thereby presenting considerable challenges to graft viability and the long-term success of transplantation endeavors. Tacrolimus (FK506), an immunosuppressive drug, was used in this study to assess its impact as a pretreatment on brain death-induced renal injury. This study aimed to investigate changes associated with brain death-induced renal injury in a 4-month-old female porcine model. The experimental groups included brain death placebo-pretreated (BD; n = 9), brain death tacrolimus-pretreated using the clinical dose of 0.25 mg/kg the day before surgery, followed by 0.05 mg/kg/day 1 hour before the procedure (BD + FK506; n = 8), and control (ctrl, n = 7) piglets, which did not undergo brain death induction. Furthermore, we aimed to assess the effect of FK506 on these renal alterations through graft preconditioning. We hypothesized that immunosuppressive properties of FK506 reduce tissue inflammation and preserve the glycocalyx. Our findings revealed a series of interconnected events triggered by BD, leading to a deterioration of renal function and increased proteinuria, increased apoptosis in the vessels, glomeruli and tubules, significant leukocyte infiltration into renal tissue, and degradation of the glycocalyx in comparison with ctrl group. Importantly, treatment with FK506 demonstrated significant efficacy in attenuating these adverse effects. FK506 helped reduce apoptosis, maintain glycocalyx integrity, regulate neutrophil infiltration, and mitigate renal injury following BD. This study offers new insights into the pathophysiology of BD-induced renal injury, emphasizing the potential of FK506 pretreatment as a promising therapeutic intervention for organ preservation, through maintaining endothelial function with the additional benefit of limiting the risk of rejection.

Inappropriate Secretion of Antidiuretic Hormone after Pancreatoduodenectomy for Pancreatic Head Cancer: A Case Report and Literature Review

Syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is a disease that leads to dilute hyponatremia through excessive secretion of antidiuretic hormone. SIADH has various causes, including ectopic ADH-producing tumors, drug properties, and can be idiopathic. But there have been very few reports of cases in which SIADH has developed after surgery for malignant tumors. In addition, few cases have been reported where this disease has developed after surgery for pancreatic cancer, because the symptoms of hyponatremia are non-specific. These symptoms are particularly gastrointestinal symptoms; therefore, it is difficult to differentiate them, even if SIADH has developed after gastrointestinal surgery. The patient in our case was an 80-year-old woman. She had persistent epigastralgia and left back pain. Imaging studies revealed a tumor in the head of the pancreas, which was diagnosed as pancreatic head cancer. We performed subtotal stomach-preserving pancreatoduodenectomy. After the operation, she complained of appetite loss and general fatigue. Her serum sodium levels decreased to 109 mEq/L on postoperative day 11. She was diagnosed with SIADH using the SIADH diagnostic criteria listed by the Japanese Ministry of Health, Labor and Welfare. We treated the patient with sodium supplementation for hyponatremia, and her symptoms ameliorated. After the event, she did not relapse with hyponatremia. This case is significant in that we performed differential diagnosis after major gastrointestinal surgery for pancreatic cancer and diagnosed SIADH at an early stage.