USE OF A NUTRITIONAL STRATEGY TO IMPROVE RESPIRATORY COURSE IN A PATIENT WITH SEVERE INFANTILE SPINAL MUSCULAR ATROPHY

Abstract

PURPOSE: Patients with severe infantile spinal muscular atrophy (SMA) often die of respiratory complications. Gastrostomy, noninvasive ventilation (NIV), and gastroesophageal reflux therapy may not prolong survival. We describe a nutritional strategy that improved the respiratory course of a child with severe SMA. METHODS: This 4 year-old was diagnosed with SMA prior to age 6 months. Began NIV and assisted cough at age 14 months; gastrostomy placed at 29 months, at which time the nutritional strategy was begun, which involved feeding a 25% fat, free amino acid formula via gastrostomy to achieve 100% of caloric requirements, even during acute respiratory illnesses. Retrospective chart review from August 2006-April 2009, recording: weight, feeding method, intake as percent of caloric requirement, ketonuria, and days of hospitalization/intubation before and after initiation of the nutritional strategy. No changes in NIV, assisted cough or anti-reflux medication throughout time period. RESULTS: Over the 13 months before the nutritional strategy was begun, patient received a 44% fat, milk protein formula, achieving 55%-75% of caloric requirement and losing 1.1 kgs. There were 4 inpatient admissions involving 50 hospital days and 24 days of intubation. Ketonuria on 3 of 4 admissions. Over the 13 months after the nutritional strategy began, patient achieved 80-100% of caloric requirement and gained 1.2 kgs. She had two admissions involving 16 inpatient days, no intubations or ketonuria. Erythromycin was begun for G.I. motility. Over the subsequent 7 months, she received 100% of caloric requirement and gained 3.1 kgs, with no hospitalizations. CONCLUSION: The respiratory course of our patient with severe SMA improved after starting enteral feeding with lower fat, free amino acid formula via gastrostomy tube; delivery of 80-100% of the patient's caloric requirement; pro-kinetic medication; and full enteral feeding during acute respiratory illnesses, avoiding ketonuria. CLINICAL IMPLICATIONS: In severe SMA, a link exists between respiratory course and nutrition. The relative role of reflux, G.I. dysmotility, malnutrition, dysphagia and metabolic abnormalities requires study. Adequate caloric intake and avoiding ketosis during respiratory illnesses may help prevent respiratory failure.