Case Series of Continuous Renal Replacement Therapy in Organic Acidemias

Introduction: As critical care advances, technologies and life support systems that were selectively applied gain expanded use. However, it is important to carefully evaluate how these therapies interact with underlying chronic diseases. This is especially important in diseases that previously had shorter life expectancies. Propionic acidemia (PA) and methylmalonic acidemia (MMA) are two similar, autosomal recessive, inborn errors of metabolism. Severe metabolic crises can develop from dietary non-compliance, infectious triggers, or stress. Here, we report a single center experience with the use of continuous renal replacement therapy (CRRT) in this patient population.


Description: During a 5-year period, at a tertiary academic pediatric hospital, there were 5 cases of initiation of CRRT for metabolic crisis in children with PA or MMA. Of these 5 cases, one patient with MMA had undergone a liver transplant but developed graft failure leading to a hyperammonemia crisis and acute kidney injury requiring CRRT. This patient tolerated CRRT until repeat liver transplant but ultimately died due to complications from her transplant. The other four cases were patients experiencing metabolic crisis from their underlying inborn error of metabolism. CRRT was offered to help correct the severe refractory metabolic acidosis. One family declined CRRT and redirected care. For the other three cases of CRRT use in metabolic crisis for PA/MMA, data including presenting symptoms, metabolic support, initial labs, VIS, PELOD-2, and pSOFA scores are reported as well as these same values at the initiation of CRRT and after 24 hours of CRRT.


Discussion: Unfortunately, although all patients met criteria for initiation of CRRT due to severe refractory metabolic acidosis, all patients died. This raises the question on whether the application of CRRT is a useful therapy to help abort or manage a metabolic crisis in patients with PA/MMA. Perhaps, once multi-organ dysfunction develops in the PA/MMA patient population, CRRT is insufficient to reverse the ongoing metabolic injury. This is a small case series and raises the need for a future multi-institutional registry to evaluate the optimal treatment and management for severe refractory acidosis in patients with PA/MMA.