To the Editor:
Hunter syndrome is a progressive lysosomal storage disease caused by a deficiency of the enzyme iduronate sulfatase. Such patients represent a challenge for the anesthesiologist because of glycosaminoglycan accumulation within the walls of the airway. Patients with Hunter syndrome undergo multiple surgeries during their average lifespan of <30 yr, with their death attributed to upper respiratory tract infections and cervical and cardiac diseases.1 However, the recently approved therapeutic agent iduronate may perhaps slow or prevent new glycosaminoglycan accumulation, extending patient lifespan further into adulthood.2
Recently, we treated a 36-yr-old man with Hunter syndrome taking iduronate, who required decompression for severe symptomatic cervical spinal stenosis. Preoperatively, airway evaluation revealed a 4-cm mouth opening, thyromental distance of 4.8 cm, macroglossia with a Mallampati Grade IV airway assessment, and a short, thick neck. A preoperative chest radiograph and magnetic resonance imaging (MRI) of the cervical spine were obtained, with only the MRI showing severe tracheal stenosis (Fig. 1).
Based on the airway examination and MRI, we chose an awake fiberoptic intubation with a microlaryngeal endotracheal tube. During tracheal tube placement, we observed both large swollen aryepiglottic folds and tracheal narrowing. The tip of the tracheal tube was placed 2–3 cm above the carina with some resistance, and a small amount of blood was observed in the distal trachea and right main bronchus. The bleeding stopped after suctioning and observation for 15 min. The intraoperative course was uneventful. After surgery, the patient was placed supine, the head of the bed elevated to 80°, and when the patient was able to follow commands, a Cook exchange catheter was placed through the tracheal tube and the tracheal tube removed. The catheter remained in the trachea until the patient was alert. The patient was then monitored in the intensive care unit for 24 h and experienced an uneventful postoperative course.
Although Hunter syndrome is infrequently seen in adult anesthesia practice, iduronate therapy may increase the incidence of surgeries occurring in adult patients with Hunter syndrome. Adult patients with Hunter syndrome require an extensive preoperative airway evaluation, including computed tomography or MRI of the trachea, to avoid operative complications associated with intubation and extubation.
Eric R. Gross, MD, PhD
Hendrikus J. M. Lemmens, MD, PhD
Department of Anesthesiology
1. Wraith JE, Scarpa M, Beck M, Bodamer OA, Meirleir LD, Guffon N, Lund AM, Malm G, Van der Ploeg AT, Zeman J. Mucopolysaccharidosis type II (Hunter syndrome): a clinical review and recommendations for treatment in the era of enzyme replacement therapy. Eur J Pediatr 2008;167:267–77
2. Meunzer J, Wraith JE, Beck M, Giugliani R, Harmatz P, Engl CM, Vellodi A, Martin R, Ramaswami U, Gucsavas-Calikoglu M, Vijayaraghavan S, Wendt S, Puga AC, Ulbrich B, Shinawi M, Cleary M, Piper D, Conway AM, Kimura A. A phase II/III clinical study of enzyme replacement therapy with idursulfase in mucopolysaccharidosis II (Hunter syndrome). Genet Med 2006;8:465–73