Unexpectedly severe metabolic acidosis associated with sodium thiosulfate therapy in a patient with calcific uremic arteriolopathy.

Calcific uremic arteriolopathy, formerly known as calciphylaxis is a devastating condition that primarily affects patients with end-stage renal disease. The lesions can progress to massive ulcerations of the subcutaneous tissue that are associated with a high degree of morbidity and mortality, usually related to sepsis. Although the pathophysiology of this condition is poorly understood, it appears to be related to a derangement in calcium-phosphate metabolism. Thus, treatments have focused on the treatment of hyperparathyroidism albeit with poor results. More recently, sodium thiosulfate (STS) has emerged as a promising therapy following multiple case reports of marked disease regression following its use. As STS is a strong acid, metabolic acidosis has been described following its administration, although relatively mild in degree. We report a case of a patient with calciphylaxis who repeatedly developed a severe anion gap metabolic acidosis following each dose of STS requiring a significant reduction in the dose.

A large pleural effusion in a patient receiving peritoneal dialysis.

Hydrothorax as a complication of peritoneal dialysis (PD) is a rare but recognized event. Proposed mechanisms for the development of a pleuro-peritoneal communication include congenital diaphragmatic defects, acquired weakening of diaphragmatic fibers caused by high intra-abdominal pressures during peritoneal dialysis, and impairments in lymphatic drainage. Pleural fluid analysis and diagnostic imaging assist in differentiation from other causes of pleural effusion. Nearly 50% of patients with this diagnosis have resolution of hydrothorax after temporary cessation of PD with interim hemodialysis for 2-6 weeks. Historically, other treatment options have included conventional pleurodesis and open thoracotomy with direct repair, producing variable results. With the advent of video-assisted thoracoscopy (VATS), surgical repairs and pleurodesis are now frequently performed under direct visualization with minimal invasiveness. We report a case of hydrothorax in a patient after recent introduction to peritoneal dialysis. Pleuro-peritoneal communication was documented with thoracentesis and radionuclide scanning. VATS pleurodesis with talc was performed. Repeat scintigraphy performed 1 week after the procedure revealed no residual communication, and patient was able to resume PD without further complications.