[Differential diagnosis of hypersomnia in surgical sleep medicine-more than just sleep apnea!]

Otorhinolaryngologists play a vital role in the management of patients with obstructive sleep apnea (OSA) in Germany, particularly with regards to outpatient diagnostics as well as conservative and surgical treatment of patients with intolerance to ventilation therapy. Although establishment of differential indications for surgical therapy and performance of additional preoperative drug-induced sleep endoscopy in patients with sleep-disordered breathing are among the core competencies of otorhinolaryngologists, differential diagnostic considerations and detection of comorbid sleep disorders can be challenging, particularly for those without extensive sleep medicine training and experience. However, detection of comorbid sleep disorders is of particular importance when permanent surgical treatment is considered. Daytime sleepiness is the typical leading symptom of OSA; nevertheless, other disorders of hypersomnolence need to be considered in these patients and can easily be overlooked. This may lead to inadequate indications for surgical treatment. Based on two case reports, narcolepsy is presented as a comorbid disorder and differential diagnosis in patients with OSA.