<unk>  presents with non-specific symptoms and signs that make differential diagnosis difficult to achieve. Furthermore, symptoms of the disorder overlap greatly with symptoms of other disorders. Therefore,<unk>  is under-diagnosed and under-treated. As there are multiple potential etiologies for the respiratory and laryngeal symptoms of<unk> , diagnosing<unk>  based on symptoms alone is unreliable. Laryngoscopic findings such as erythema, edema, laryngeal granulomas, and interarytenoid hypertrophy have been used to establish the diagnosis; however, these findings are nonspecific and have been described in the majority of asymptomatic subjects undergoing laryngoscopy. Response to acid-suppression therapy has been suggested as a diagnostic tool for confirming diagnosis of<unk> , but studies have shown that the response to empirical trials of such therapy (as with proton-pump inhibitors) in these patients is often disappointing. Several studies have emphasized the importance of measuring proximal esophageal, or ideally pharyngeal acid exposure, in patients with clinical symptoms of<unk>  to document<unk>  as the cause of the symptoms. Additionally, several potential biomarkers of<unk>  have been investigated. These include inflammatory cytokines, carbonic anyhydrase, E-cadherin and mucins; however, their direct implications in<unk>  are still being established. The presence of pepsin, an enzyme produced in the stomach, in the hypopharynx has also become an increasingly researched biomarker for<unk> . Research suggests that the stomach enzyme pepsin plays a crucial role in the complex mechanism behind<unk> . Once present in the larynx pepsin is active at a low pH, but persists even when inactive. Pepsin can manifest both extracellularly and intracellularly; however, damage is realized differently in these two environments. Intracellularly, pepsin enters the laryngeal tissue through endocytosis and causes damage that accumulates over time. Pepsin has implications on cellular transcription and therefore, gene expression, which subsequently leads to the recruitment of inflammatory cells, but inhibition of protective mechanisms such as growth factors. Structurally, pepsin plays a role in increasing viscosity of the vibratory portion of the vocal folds and decreasing cellular water retention, which reduces the overall thickness of the vocal folds. These morphological changes result in decreased vibratory amplitude, increasing demands for initiating vibration and ultimately, impacting voice quality. Before a diagnosis can be made, a physician will need to record the patient's medical history and ask for details about the presenting symptoms. Questionnaires such as the<unk>  Symptom Index (RSI), Quality-of-Life Index (QLI) for<unk> , Glottal Closure/Function Index (GCI) and Voice Handicap Index (VHI) can be administered to gain information about the patient's medical history as well as their symptomatology. A physical examination will then need to be performed with particular concentration around the head and neck. A scope with a specialized camera lens made of fiber optic strands is gently fed down the throat and feeds back images to a monitor. This provides a clear view of the throat and larynx. Signs of<unk>  include redness, swelling, and obvious irritation. Other, more invasive tests, such as fibre-optic transnasal laryngoscopy, 24-hour ambulatory dual probe pHmetry, pharyngeal pHmetry, transnasal esophagoscopy (TNE) and biopsy may be used. A noninvasive test for diagnosis of<unk>  is the collection of<unk> ate where the<unk> ed material is collected and analyzed. Another noninvasive diagnostic test that can be used is an empirical trial of proton-pump inhibitor therapy; however, this test is mostly successful in diagnosing GERD. There is no agreed-upon assessment technique to identify<unk>  in children. Of the debated diagnostic tools, multichannel intraluminal impedance with pH monitoring (MII-pH) is used as it recognizes both acid and non-acid<unk> . A more common technique that is used is 24-hour dual probe pH monitoring. Both of these tools are expensive and are therefore not widely used.
Laryngopharyngeal reflux
Subglottic stenosis
Laryngomalacia
Velopharyngeal insufficiency
Laryngotracheal stenosis
Post-nasal drip
Exercise-induced laryngeal obstruction
Nasal septum deviation