In a survey of patients with Spinal Muscular Atrophy (SMA), more than half of caregivers reported gastroesophageal reflux disease (GERD), and gastroesophageal motility issues are well-documented in patients with progressive neuromuscular disease.1,2 Esophageal dysmotility and reflux is inevitable in the most severe forms of SMA, and thus for these patients treatment of GERD is necessary for both symptomatic relief and for prevention of aspiration of stomach contents.3 There is evidence from animal models of SMA that esophageal motility may be due to a disruptions in the enteric nervous system, but this suggestion awaits correlation in human pathology.4
A consortium of SMA experts notes that swallowing safety is a priority for the weakest patients with SMA, those who lack the ability to sit or so-called “non-sitters,”.5 The experts recommend that non-sitter patients with SMA undergo a video fluoroscopic swallow study at diagnosis, if growth failure has occurred, or when evidence of dysphagia is present.5 If the “non-sitter” patient fails the study, the consensus statement recommends referral for a Nissen fundoplication with gastrostomy tube placement.5 Experts urge early placement of a gastrostomy tube for primary prevention of reflux and related complications.3 This recommendation is widely implemented as most severely affected SMA patients have these procedures done.1 These procedures are well-tolerated in even the most serious forms of SMA.3,6 Rarely a patient with SMA may need a gastro-jejunal bypass tube because of intolerance of gastric feeding, but this measure should be considered when patients have evidence of post-feeding abdominal pain.2 Surgical correction of scoliosis, a common complication in SMA, may also improve reflux by encouraging more appropriate anatomical alignment of the esophagus and stomach.7 Even the most aggressive approach to gastroesophageal reflux in SMA is not an assurance of preventing complications, however.8
Experts advocate that patients with SMA with mobility despite weakness, “sitters” should have periodic assessment of their swallowing safety.5 The therapy needs of these patients with SMA may change as they grow older and re-assessments should be performed. Less aggressive management with prokinetic and acid reduction therapies can be used in this population without a need for surgical intervention.5
References
1. Davis RH, Godshall BJ, Seffrood E, et al. Nutritional practices at a glance: Spinal muscular atrophy type i nutrition survey findings. Journal of child neurology. 2014;29(11):1467-1472.
2. Tilton AH, Miller MD, Khoshoo V. Nutrition and swallowing in pediatric neuromuscular patients. Seminars in pediatric neurology. 1998;5(2):106-115.
3. Durkin ET, Schroth MK, Helin M, Shaaban AF. Early laparoscopic fundoplication and gastrostomy in infants with spinal muscular atrophy type i. J Pediatr Surg. 2008;43(11):2031-2037.
4. Gombash SE, Cowley CJ, Fitzgerald JA, et al. Smn deficiency disrupts gastrointestinal and enteric nervous system function in mice. Hum Mol Genet. 2015;24(13):3847-3860.
5. Mercuri E, Finkel RS, Muntoni F, et al. Diagnosis and management of spinal muscular atrophy: Part 1: Recommendations for diagnosis, rehabilitation, orthopedic and nutritional care. Neuromuscular disorders : NMD. 2018;28(2):103-115.
6. Yeh TC, Yeung CY, Sheu JC, et al. Percutaneous endoscopic gastrostomy in children: 15 cases experience. Acta paediatrica Taiwanica = Taiwan er ke yi xue hui za zhi. 2003;44(3):135-139.
7. Yang JH, Kasat NS, Suh SW, Kim SY. Improvement in reflux gastroesophagitis in a patient with spinal muscular atrophy after surgical correction of kyphoscoliosis: A case report. Clinical orthopaedics and related research. 2011;469(12):3501-3505.
8. Birnkrant DJ, Pope JF, Martin JE, Repucci AH, Eiben RM. Treatment of type i spinal muscular atrophy with noninvasive ventilation and gastrostomy feeding. Pediatr Neurol. 1998;18(5):407-410.