Administration of bicarbonates through percutaneous gastrostomy with continuous nocturnal infusion in a patient with Kearns-Sayre disease: a life changing therapeutical paradigm

Background: Mitochondrial diseases (MDs) are systemic disorders that can affect multiple organs. Renal manifestations, including renal tubular acidosis, are common because kidneys are particularly vulnerable to energy deprivation. Treatment of MDs is often complex and electrolyte replacement can be difficult especially in pediatric patients, because large and repeated amounts of oral supplements are needed but are not well tolerated. Case presentation: We describe the case of a girl affected by Kearns-Sayre disease with severe renal tubular acidosis. The management of her metabolic acidosis was challenging because she showed persistent low levels of serum bicarbonates despite a progressive incrementation of oral bicarbonates. Furthermore, as a result to the ingestion of large amounts of alkali, the girl developed an aversion to oral supplementation. After positioning a percutaneous gastrostomy (PEG) and starting enteral administration of bicarbonates (with daily boluses and continuous nocturnal infusion), she finally obtained an adequate electrolyte control, with a significant increase in her quality of life. Conclusions: In MDs, the combination of nocturnal continuous enteral administration of alkali plus diurnal boluses may represent a valid solution to correct metabolic acidosis. It can also result in an improved patients' quality of life, particularly in pediatric settings, where compliance to oral therapy is often lacking due to the large and repeated amounts of unpalatable bicarbonates solutions required.