Pulmonary Function Test, Bronchial Hyperresponsiveness and Quality of Life in Patients With Vocal Cord Dysfunction (VCD)

Study Overview
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Brief Summary
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Vocal cord dysfunction is a rare clinical picture. It is labeled as a sudden and threatening dyspnea. Patients with VCD may also present cough, hoarseness, wheezing, and chest tightness, but an inspiratory stridor is the most common symptom. For this reason, such patients are often misdiagnosed with refractory asthma, because of poor response to steroids and bronchodilators. Diagnosis is suspected on clinical grounds and is confirmed with laryngoscopy. The therapy consists of education, speech therapy and if necessary psychotherapy. The purpose of the investigators' study is to characterize children, adolescents, and young adults with VCD, and the evaluation of predictors as atopy, bronchial hyperresponsiveness, and psychiatric features.

Detailed Description
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VCD appears to be significantly more common among females. The episode of dyspnea underlies the paradoxical, intermittent adduction of the vocal cords during inspiration. Methacholine challenge testing combined with laryngoscopy is useful in differentiating vocal cord dysfunction from asthma during the asymptomatic period. In one visit patients will be characterized with a questionnaire based on the ISAAC questionnaire. Furthermore, FeNO, eCO, skin prick testing and total serum IgE will be examined. The psychiatric condition of patients will be determined by CBCL/6-18 and YSR/11-18 behavior questionnaires. After initial fiberoptic laryngoscopy and pulmonary function testing, bronchoprovocation is performed using nebulized methacholine at increasing doses, until a 20% decline in the forced expiratory volume in 1 second is achieved (PD20FEV1). Each methacholine testing will be followed by a second laryngoscopy and pulmonary function testing. The visualization of paradoxical vocal cord motion during inspiration will be recorded.

Official Title
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Pulmonary Function Test, Bronchial Hyperresponsiveness and Quality of Life in Patients With Vocal Cord Dysfunction (VCD)

Conditions
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Dyspnea

Intervention / Treatment
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* Other: Methacholine challenge testing
* Procedure: Rhino-laryngoscopy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Informed consent Age 7 to 30 Years Documented VCD or strong suspicion of VCD Pulmonary function test: FEV1 (% pred.) ≥ 70% Exclusion Criteria: Age < 7 and > 30 Years Pulmonary function test: FEV1 (% pred.) < 70% Others chronic diseases or infections (e.g., HIV, tuberculosis, malignancy) Pregnancy Documented alcohol, substance, and/or drug abuse Incapability to perform all study procedure Current participation in another clinical trial

Ages Eligible for Study
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Minimum Age: 7 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Vocal cord dysfunction<br>Patients with suspicion of VCD | Other: Methacholine challenge testing<br>* Nebulized methacholine administered at the following doses: 0,1 mg/0,4 mg/0,8 mg/1,6 mg<br>* Other names: Aerosol Provocation System (Cardinal Health GmbH);Procedure: Rhino-laryngoscopy<br>* Topical anesthesia (Xylocain Pump spray) followed by transnasal fiberoptic laryngoscopy with a flexible fiberoptic laryngoscope.<br>* Other names: ENF-V2 laryngoscope Olympus;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Characterization of vocal cord dysfunction, and evaluation of predictors as atopy, bronchial hyperresponsiveness, and psychiatric behavior. |  | one day | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vocal cord dysfunction, Laryngoscopy, Methacholine challenge, Pulmonary function testing