- Email: [email protected]
Vocal cord dysfunction: A rare cause of stridor in children
International Journal of Pediatric Otorhinolaryngology Extra 6 (2011) 13–16
Contents lists available at ScienceDirect
International Journal of Pediatric Otorhinolaryngology Extra journal homepage: www.elsevier.com/locate/ijporl
Case report
Vocal cord dysfunction: A rare cause of stridor in children Alaa Hazem Gaafar a,*, Nader Abdelmonem Fasyh b a b
Department of Otolaryngology Head & Neck Surgery, Faculty of Medicine, Alexandria University, Egypt Department of Pediatric, Faculty of Medicine, Alexandria University, Egypt
A R T I C L E I N F O
A B S T R A C T
Article history: Received 2 October 2009 Received in revised form 5 December 2009 Accepted 7 December 2009 Available online 8 January 2010
Background: Vocal cord dysfunction (VCD) has been defined as adduction of the true vocal cords on inspiration with abduction on expiration. It is most common in females aged between 20 and 45 years. However, cases in children have been reported. Patients with vocal cord dysfunction present with distressing shortness of breath, inspiratory stridor and breathy dysphonia. VCD is most frequently diagnosed as asthma since the attacks in both begin and end suddenly and produce distressing breathing difficulties. Study design: Infants and children presented with respiratory distress secondary to vocal cord dysfunction were included in this study. Diagnosis of VCD depended mainly on direct laryngoscopy either using flexible laryngoscopy with topical anesthesia or direct laryngoscopy under general anesthesia with spontaneous respiration. The typical finding of adduction of the anterior two-third of the vocal cords during inspiration was the key point for diagnosis of VCD. Any further investigation was done according to the etiology of each case. Results: One infant and four children were included in this study. They were three boys and two girls. Their ages were 1, 12, 14, 10 and 2 years. The etiology of VCD was bulbar myasthenia gravis in one case, multiple system atrophy in one case, Laryngopharyngeal reflux in two cases, and post-nasal drip in one case. Diagnosis of VCD was done using pediatric flexible fibreoptic laryngoscopy with topical anesthesia in two cases and by direct laryngoscopy under general anesthesia with spontaneous respiration in three cases (in one of them the vocal cords were visualized during urgent intubation). Three cases were misdiagnosed as bronchial asthma and they were receiving treatment of asthma with no improvement. Conclusion: Vocal cord dysfunction represents a potentially overlooked differential diagnosis of recurrent dyspnea in children. It is always misdiagnosed as bronchial asthma. It should be suspected in every child with atypical or corticosteroid resistant asthma. ß 2009 Elsevier Ireland Ltd. All rights reserved.
Keywords: Vocal cord dysfunction Paradoxical vocal cord motion Children Stridor
1. Introduction Vocal cord dysfunction (VCD) has been defined as adduction of the true vocal cords on inspiration with abduction on expiration [1]. Various terms including vocal cord dysfunction, paradoxical vocal cord motion (PVCM), episodic laryngeal dyskinesia, factitious asthma, and paroxysmal laryngospasm are used to describe this syndrome [2,3]. It is most common in females aged between 20 and 45 years [4]. However, cases in children have been reported [5,6]. Patients with vocal cord dysfunction present with distressing shortness of breath, inspiratory stridor and breathy dysphonia. Occasionally symptoms may include expiratory stridor, coughing, dysphagia and excessive musculo skeletal tension [7]. VCD is most frequently diagnosed as asthma since the attacks in both begin and end suddenly and produce distressing breathing difficulties [8].
* Corresponding author at: Aly Ramez Street, No. 7, Ramleh station, Alexandria, Egypt. Tel.: +20 127435699. E-mail address: [email protected] (A.H. Gaafar). 1871-4048/$ – see front matter ß 2009 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.pedex.2009.12.002
The etiology of vocal cord dysfunction is not yet clear. The neurological explanation suggests that efferent motor vagal innervation is activated, producing a change in laryngeal muscle tone thus lowering threshold for stimuli to produce vocal cord spasm [9]. Many clinical reports described the presence of laryngeal irritation by post-nasal drip or gastroesophageal reflux as an etiology of vocal cord dysfunction [9,10]. The etiological importance of gastroesophageal reflux is supported by the clinical findings that anti-reflux drug therapy can lead to relief in paradoxical vocal cord movement [10]. A third possible explanation of the condition is that it represents a psychological conversion reaction. The abnormal laryngeal movement may serve the purpose of enabling the patient to avoid confrontation of an unpleasant life situation or emotion, and yields attention and sympathy [8,11]. The diagnosis of vocal cord dysfunction is not straightforward. Suspicions should be raised when the degree of dyspnea is out of proportion to the clinical signs and when there is little response to standard treatment [12]. The definitive diagnosis is made by indirect or fibreoptic laryngoscopy using only topical anesthesia during an acute episode. The characteristic appearance of adducted
14
A.H. Gaafar, N.A. Fasyh / International Journal of Pediatric Otorhinolaryngology Extra 6 (2011) 13–16
vocal cords with a posterior diamond-shaped chink is seen [11]. We represent cases of five children presented with vocal cord dysfunction secondary to different etiologies. Their diagnosis and management were discussed as well. 2. Material and methods This study was carried on at the Department of Otolaryngology Head & Neck Surgery and Department of Pediatric, Faculty of Medicine, Alexandria University, Egypt from January 2007 till January 2009. All infants and children presented with respiratory distress secondary to vocal cord dysfunction were included in this study. Diagnosis of VCD depended mainly on direct laryngoscopy either using flexible laryngoscopy with topical anesthesia or direct laryngoscopy under general anesthesia with spontaneous respiration. The typical finding of adduction of the anterior two-third of the vocal cords during inspiration was the key point for diagnosis of VCD. X-ray chest and tracheobronchoscopy were done to exclude other causes of airway obstruction. Further investigations were done according to the etiology of each case. 3. Results One infant and four children were included. They were three boys and two girls. Their ages were 1, 12, 14, 10 and 2 years. The etiology of VCD was bulbar myasthenia gravis in one case, multiple system atrophy in one case, laryngopharyngeal reflux in two cases, and postnasal drip in one case. Diagnosis of VCD was done using pediatric flexible fibreoptic laryngoscopy with topical anesthesia in two cases and by direct laryngoscopy under general anesthesia with spontaneous respiration in three cases (in one of them the vocal cords were visualized during urgent intubation). Three cases were receiving treatment of bronchial asthma with no improvement. 3.1. Case 1 One-year-old infant presented with recurrent attacks of respiratory distress and noisy breathing. The attack persists from few hours up to 2 days. Some times, difficulty in feeding was encountered. He was diagnosed previously as bronchial asthma, however, there was poor response to anti-asthma treatment. The parents gave history of previous baby who died at the age of 2 years from unknown neurological disease. Examination during the attack revealed moderate respiratory distress with no cyanosis, noisy breathing which was mainly inspiratory, retraction of suprasternal and intercostal spaces. Chest auscultation showed wheezy chest. X-ray chest was irrelevant and blood gases was within the normal levels. Direct laryngoscopy under general anesthesia with spontaneous respiration was done. It revealed the classical picture of vocal cord dysfunction with adduction of the anterior 2/3 and abduction of the posterior 1/3 of the vocal cords during inspiration (Fig. 1). Tracheobronchoscopy was irrelevant. Neostigmine test was done and it proved to be bulbar myasthenia gravis. The attacks of respiratory distress improved dramatically on myasthenia medication and plasmapheresis.
Fig. 1. Endoscopic picture of the larynx of case no. 1 (a) during inspiration showing adduction of the anterior two-third of the vocal cord with abduction of the posterior third and (b) during expiration showing abduction of the vocal cords.
bronchodilator and corticosteroids. These attacks increased gradually in time and intensity and it can occur at any time of the day. Also the parents noticed that she had abnormal gait, and mild imbalance since 18 months. X-ray chest, airway endoscopy and CT scan neck and chest all were free. Weaning of intubation failed and tracheostomy was done after 7 days. Neurological examination showed mild parkinsonism, left babinski sign, and severe dysautonomia. MRI brain showed posterior putamen hypointensity, atrophy of transverse fibres of the pons, the cerebellum, the middle cerebellar peduncles, and the inferior olives (Fig. 2). She was diagnosed as having multiple system atrophy (MSA). 3.3. Case 3 Fourteen-year-old boy presented with recurrent attacks of respiratory distress and apneic attacks which persists for few minutes. The attacks sometimes occur during sleep and the patient arose on the feeling of ‘‘Dying’’. During examination the patient developed an attack of difficult noisy breathing with suprasternal retraction. Flexible nasopharyngolaryngoscopy using pediatric flexible laryngoscope under topical anesthesia revealed the classical picture of vocal cord dysfunction. In addition, the larynx
3.2. Case 2 Twelve-year-old girl presented to the emergency department by severe respiratory distress and cyanosis. Urgent intubation was done. During intubation the vocal cords were visualized showing adduction of the anterior two-third during inspiration. The parents stated that their daughter started to complaint of attacks of respiratory difficulty mainly at night since 2 years. It was diagnosed as bronchial asthma with no improvement on
Fig. 2. MRI Sagittal T1-weighted image of case no. 2 with multiple system atrophy demonstrates atrophy of transverse fibres of the pons, the cerebellum, the middle cerebellar peduncles, and the inferior olives (arrow).
A.H. Gaafar, N.A. Fasyh / International Journal of Pediatric Otorhinolaryngology Extra 6 (2011) 13–16
and the upper trachea showed diffuse congestion mainly at the posterior part with oedema over both arytenoids. X-ray chest, blood gases and MRI brain all were free. The case was diagnosed as reflux laryngitis. The patient responded well to anti-reflux treatment and the attacks of respiratory distress disappeared. 3.4. Case 4 Ten-year-old boy presented with recurrent attacks of respiratory distress since 4 years. The attack persisted for few hours. Examination of the child during the attack showed tachypnea, change of voice, flushed face, wheezy chest, suprasternal retraction. X-ray chest and blood gases were irrelevant. The patient was diagnosed as a case of bronchial asthma. There was poor response to anti-asthma treatment with subsequent increase in the dose of corticosteroids, however, with no improvement in the frequency or intensity of the attacks. Flexible nasopharyngolaryngoscopy under local anesthesia was planned to visualize the airway. During the endoscopy the child developed an attack of distress with immediate change in the movement of the vocal cords from the normal pattern into abnormal adduction of the anterior two-thirds during inspiration. Except from mild congestion in the posterior parts of the arytenoids, the larynx and the trachea were free. The patient received anti-reflux treatment in conjunction with antiasthma treatment with subsequent improvement in the frequency and intensity of the attacks. 3.5. Case 5 Two-year-old girl presented with snoring, nocturnal coughing and attacks of prolonged irritating cough followed by noisy breathing and respiratory distress for few minutes. The condition started following severe attack of upper respiratory tract infection since 2 months. Examination during the attack revealed respiratory distress with inspiratory sound, suprasternal and intercostals retraction and scattered ronchi on the chest. Local examination revealed rhinitis, post-nasal discharge and congested posterior pharyngeal wall. X-ray nasopharynx showed adenoid hypertrophy. X-ray chest was free. The condition improved partially on antibiotic and nasal decongestant therapy. Decision of adenoidectomy was done. During induction of anesthesia the larynx was visualized using the nasal endoscope zero degree, 4 mm and it revealed the classical picture of vocal cord dysfunction. After adenoidectomy the condition was totally improved. 4. Discussion Vocal cord dysfunction is a well-recognized respiratory condition in which active adduction of the vocal cords during inspiration causes functional airway obstruction [13]. VCD has been described in adults and children. While VCD mostly occurs in females aged 20–40 years [4], we report one infant and 4 children with VCD, three of them were boys. The ages of our patients were 1, 12, 14, 10, and 2 years. Previous reports stated that VCD in children occurs most commonly in age of 10–15 years [14,15], and less commonly it can occur in infants [16,17]. Diagnosis of VCD is done by visualizing the vocal cords during the attack using flexible laryngoscopy under topical anesthesia [11]. In pediatric age group, this will not be feasible in every case. Infants and uncooperative child will be obstacle for diagnosis using flexible laryngoscopy. In our cases we were able to diagnose two out of five patients using flexible laryngoscopy under topical anesthesia. The other three cases were diagnosed under general anesthesia with spontaneous respiration. We found that the nasal endoscope zero degree, 4 mm in diameter is very practical in diagnosis of laryngeal anomalies under general anesthesia. Its
15
length and diameter provide good quality image. Also, digital video camera could be attached to record any abnormal movement in the larynx. Beside laryngoscopy, other measures for directly assessing dysfunction of the vocal cords have been reported in the literature, such as computerized laryngeal ultrasound investigations, which have the advantage of being non-invasive, painless and widely accepted [33]. However, this technique requires experience which cannot be obtained in most centers. The etiology of VCD in our patients was bulbar myasthenia gravis in one patient, multiple system atrophy in one patient, laryngopharyngeal reflux in two patients and post-nasal drip in one patient. Myasthenia gravis is an acquired disorder of the neuromuscular junction caused by antibodies against the acetylcholine receptor of the striated muscle endplate [18]. Muscles innervated by cranial nerves (bulbar muscles) are usually the first and most seriously involved in myasthenia gravis causing ptosis, dysphagia, dysarthria and dysphonia [19]. Respiratory impairment in myasthenia gravis is usually attributed to weakness of the diaphragm and other muscles that move the chest wall [20]. However, another cause of respiratory impairment in myasthenia gravis is upper airway obstruction. Schmidt et al. [20] and Marlowe et al. [21] sated that the most important dysfunction of the upper airway leading to respiratory failure is laryngeal muscle weakness causing abnormal adduction of the vocal cords. In our case, diagnosis of bulbar myasthenia gravis was suspected due to the association of ptosis and generalized weakness and after exclusion of other causes of VCD. It was proved by neostigmine test. The condition improved on anticholinesterase and plasmapheresis. Maryann and Robert in 1996 [22] reported five children with myasthenia gravis presented with upper airway obstruction secondary to laryngeal dysfunction, all of them improved on myasthenia medication. Multiple system atrophy is a neurodegenerative disorder causing various combinations of systemic degeneration in the cerebellar, extrapyramidal and autonomic systems. Nocturnal stridor and selective paralysis of the vocal cord abductor frequently develop in MSA patients [23,24]. It had been thought that the MSA-related stridor results from passive glottis narrowing attributed to both abductor paralysis and the Bernoulli effect causing collapse of the vocal cords during inspiration [13]. However, electromyographic studies during sleep showed that the vocal cord adductor is activated during inspiration when the characteristic stridor develop in MSA patients. Therefore, the MSA related laryngeal stridor depends on active glottis narrowing as well as passive narrowing [25,26]. In our case, the typical nocturnal stridor at the beginning with the associated neurological manifestations suggested the diagnosis of MSA. This was confirmed by the radiological signs in the form of atrophy of transverse fibres of the pons, the cerebellum, the middle cerebellar peduncles, and the inferior olives in MRI T1-weighted image [27]. Brancatisano and Engel [28] have speculated in their review published in 1988 that some laryngeal reflexes contribute to generation of VCD. A similar concept has recently been postulated giving the name; the irritable larynx syndrome [3,29]. It stated that laryngeal closure reflex is augmented in patients with VCD such that various extrinsic and intrinsic stimuli can trigger reflective glottis closure as an adaptive protective response, and these laryngeal stimulus conditions lower the threshold levels for the initiation of glottis closure reflex. VCD frequently develops after laryngeal irritation including infections of the upper respiratory tract [10], gastroesophageal reflux disease [29], inhaled irritant exposure and strong odors [30], post-nasal drip [10] and thyroid surgery [31]. In our cases, three out of five were secondary to laryngeal irritation, two cases secondary to gastroesophageal reflux and one secondary to upper respiratory tract infection and
16
A.H. Gaafar, N.A. Fasyh / International Journal of Pediatric Otorhinolaryngology Extra 6 (2011) 13–16
post-nasal drip. Elimination of the irritating factor improved the condition dramatically. Vocal cord dysfunction is prone to being misdiagnosed as asthma owing to its asthma-like symptoms such as stridorous wheezing and dyspnea [13]. Nigemann et al. reported VCD in three children which were misdiagnosed as bronchial asthma. In our cases, three out of five children were misdiagnosed as bronchial asthma. Therefore, unnecessary anti-asthma treatments were administrated. When children with VCD are given diagnosis of asthma, physicians are prone to conduct unnecessary aggressive therapy including high dose of corticosteroids with no significant improvement [32]. It is important for physicians to know that patients with steroid-resistant asthma may have VCD and to diagnose VCD correctly based on the mechanism of its development. Many factors can differentiate asthma from VCD including that dyspnea is mainly inspiratory, no or marginal response to bronchodilator and corticosteroids, variable flattening of the inspiratory limb of the flow-volume curve, and finally the classical endoscopic picture of the vocal cords during the attack [14]. 5. Conclusion Vocal cord dysfunction represents a potentially overlooked differential diagnosis of recurrent dyspnea in children. It is always misdiagnosed as bronchial asthma. It should be suspected in every child with atypical or corticosteroid resistant asthma. Definite diagnosis is done by direct visualization of the larynx during the attack using flexible laryngoscopy under topical anesthesia. In uncooperative child, the larynx could be visualized under general anesthesia with spontaneous respiration. References [1] R.M. Kellman, D.A. Leopold, Paradoxical vocal cord motion: an important cause of stridor, Laryngoscope 92 (1982) 58–60. [2] M.V. Andrianopoulos, G.J. Gallivan, K.H. Gallivan, PVCM, PVCD, EPL, and irritable larynx syndrome: what are we talking about and how do we treat it? J. Voice 14 (2000) 607–618. [3] K.W. Altman, C.B. Simpson, M.R. Amin, M. Abaza, R.R. Casiano, Cough and paradoxical vocal fold motion, Otolaryngol. Head Neck Surg. 127 (2002) 501–511. [4] T.J. Lacy, S.E. Mcmanis, Psychogenic stridor, Gen. Hosp. Psych. 16 (1994) 213–223. [5] G.H. Rogers, Functional inspiratory stridor in children, J. Laryngol. Otol. 94 (1980) 669–670. [6] M. Kattan, Z. Ben-Zvi, Stridor caused by vocal cord malfunction 24 (1985) 158– 160. [7] L. Sette, F. Pajno-Ferrara, S. Mocella, Vocal cord dysfunction in an asthmatic child: case report, J. Asthma 30 (1993) 407–412. [8] J. Corren, K.B. Newman, Vocal cord dysfunction mimicking bronchial asthma, Postgrad. Med. 92 (1992) 153–156.
[9] G.J. Gallivan, L. Hoffman, K.H. Gallivan, Episodic paroxysmal laryngospasm: voice and pulmonary function assessment, J. Voice 10 (1996) 93–105. [10] A.H. Campbell, H. Mestitz, R. Pierce, Brief upper airway (laryngeal) dysfunction, Aust. N.Z. J. Med. 20 (1990) 663–668. [11] K.L. Christopher, R.P. Wood, R.C. Eckert, Vocal cord dysfunction presenting as asthma, New Engl. J. Med. 308 (1983) 1566–1570. [12] D.M. Murray, P.G. Lawler, All that wheezes is not asthma, paradoxical vocal cord movement presenting as severe acute asthma requiring ventilator support. Case report, Anesthesia 53 (1998) 1002–1011. [13] S. Keisuke, I. Shiroh, N. Ken, Paradoxical vocal cord motion: a review focused on multiple system atrophy, Auris. Nasus Larynx 34 (2007) 443–452. [14] B. Niggemann, K. Paul, R. Keitzer, U. Wahn, Vocal cord dysfunction in three children—misdiagnosis of bronchial asthma? Ped. Allerg. Immunol. 9 (1998) 97–100. [15] S.E. Alpert, D.G. Dearaborn, C.M. Kercsmar, On vocal cord dysfunction in wheezy children, Ped. Pulmonol. 142 (1991) 142–143. [16] M.J. Cunningham, R.D. Eavey, D.C. Shannon, Familial vocal cord dysfunction, Pediatrics 76 (1995) 750–753. [17] D.G. Heatley, E. Swift, Paradoxical vocal cord dysfunction in an infant with stridor and gastroesophageal reflux, Int. J. Ped. Otolaryngol. 34 (1996) 149–151. [18] D.R. Grancey, F.M. Howard, M.B. Divertie, Plasmapheresis in the treatment of ventilator-dependent myasthenia gravis patients, Chest 85 (1984) 739–743. [19] J.J. Zulueta, B.L. Fanburg, Respiratory dysfunction in myasthenia gravis, Clin. Chest Med. 15 (1994) 683–691. [20] W.W. Schmidt-Nowara, E.J. Marder, P.A. Feil, Respiratory failure in myasthenia gravis due to vocal cord paresis, Arch. Neurol. 41 (1984) 567–568. [21] F.I. Marlowe, A.J. D’Angelo, Respiratory failure as the initial presentation of myasthenia gravis, Ear Nose Throat J. 68 (1989) 472–473. [22] T.P. Maryann, A.W. Robert, Myasthenia gravis and upper airway obstruction, Hest 109 (1996) 400–404. [23] R. Bannister, W. Gibson, L. Michaels, D.R. Oppenheimer, Laryngeal abductor paralysis in multiple system atrophy, Brain 104 (1981) 351–368. [24] A. Williams, D. Hanson, D. Calne, Vocal cord paralysis in the Shy-Drager syndrome, J. Neurol. Neurosurg. Psychiatry 42 (1979) 151–153. [25] S. Isono, K. Shiba, M. Yamaguchi, A. Tanaka, T. Hattori, A. Konno, Pathogenesis of laryngeal narrowing in patients with multiple system atrophy, J. Physiol. 536 (2001) 237–249. [26] E. Isozaki, R. Osanai, S. Horiguchi, T. Hayashida, K. Hirose, H. Tanabe, Laryngeal electromyography with separated surface electrodes in patients with multiple system atrophy presenting with vocal cord paralysis, J. Neurol. 241 (1994) 551– 556. [27] E. Kraft, J. Schwarz, C. Tenkwalder, T. Vogl, The combination of hypointense and hyperintense signal changes on T2-weighted magnetic resonance imaging sequences: a specific marker of multiple system atrophy? Arch. Neurol. 56 (1999) 225–228. [28] A. Brancatisano, L.A. Engel, Role of upper respiratory airway in the control of respiratory flow and lung volume in humans, in: O.P. Mathew, G. Sant’s Ambrogio (Eds.), Respiratory Function of the Upper Airway, Marcel Dekker, New York, 1988, pp. 447–517. [29] M. Morrison, L. Rammage, A.J. Emami, The irritable larynx syndrome, J. Voice 12 (1999) 447–455. [30] J.J. Perkner, K.P. Fennelly, R. Balkissoon, B.B. Bartelson, A.J. Ruttenber, Irritantassociated vocal cord dysfunction, J. Occup. Environ. Med. 40 (1998) 136–143. [31] J. Harbison, J. Dodd, W.T. McNicholas, Paradoxical vocal cord motion causing stridor after thyroidectomy, Thorax 55 (2000) 533–534. [32] K.B. Newman, U.G. Mason, K.B. Schmaling, Clinical features of vocal cord dysfunction, Am. J. Respir. Crit. Care Med. 152 (1995) 1382–1386. [33] E.M. Friedman, Role of ultrasound in assessment of vocal cord dysfunction in infants and children, Ann. Otol. Rhinol. Laryngol. 196 (1997) 199–209.
Contents lists available at ScienceDirect
International Journal of Pediatric Otorhinolaryngology Extra journal homepage: www.elsevier.com/locate/ijporl
Case report
Vocal cord dysfunction: A rare cause of stridor in children Alaa Hazem Gaafar a,*, Nader Abdelmonem Fasyh b a b
Department of Otolaryngology Head & Neck Surgery, Faculty of Medicine, Alexandria University, Egypt Department of Pediatric, Faculty of Medicine, Alexandria University, Egypt
A R T I C L E I N F O
A B S T R A C T
Article history: Received 2 October 2009 Received in revised form 5 December 2009 Accepted 7 December 2009 Available online 8 January 2010
Background: Vocal cord dysfunction (VCD) has been defined as adduction of the true vocal cords on inspiration with abduction on expiration. It is most common in females aged between 20 and 45 years. However, cases in children have been reported. Patients with vocal cord dysfunction present with distressing shortness of breath, inspiratory stridor and breathy dysphonia. VCD is most frequently diagnosed as asthma since the attacks in both begin and end suddenly and produce distressing breathing difficulties. Study design: Infants and children presented with respiratory distress secondary to vocal cord dysfunction were included in this study. Diagnosis of VCD depended mainly on direct laryngoscopy either using flexible laryngoscopy with topical anesthesia or direct laryngoscopy under general anesthesia with spontaneous respiration. The typical finding of adduction of the anterior two-third of the vocal cords during inspiration was the key point for diagnosis of VCD. Any further investigation was done according to the etiology of each case. Results: One infant and four children were included in this study. They were three boys and two girls. Their ages were 1, 12, 14, 10 and 2 years. The etiology of VCD was bulbar myasthenia gravis in one case, multiple system atrophy in one case, Laryngopharyngeal reflux in two cases, and post-nasal drip in one case. Diagnosis of VCD was done using pediatric flexible fibreoptic laryngoscopy with topical anesthesia in two cases and by direct laryngoscopy under general anesthesia with spontaneous respiration in three cases (in one of them the vocal cords were visualized during urgent intubation). Three cases were misdiagnosed as bronchial asthma and they were receiving treatment of asthma with no improvement. Conclusion: Vocal cord dysfunction represents a potentially overlooked differential diagnosis of recurrent dyspnea in children. It is always misdiagnosed as bronchial asthma. It should be suspected in every child with atypical or corticosteroid resistant asthma. ß 2009 Elsevier Ireland Ltd. All rights reserved.
Keywords: Vocal cord dysfunction Paradoxical vocal cord motion Children Stridor
1. Introduction Vocal cord dysfunction (VCD) has been defined as adduction of the true vocal cords on inspiration with abduction on expiration [1]. Various terms including vocal cord dysfunction, paradoxical vocal cord motion (PVCM), episodic laryngeal dyskinesia, factitious asthma, and paroxysmal laryngospasm are used to describe this syndrome [2,3]. It is most common in females aged between 20 and 45 years [4]. However, cases in children have been reported [5,6]. Patients with vocal cord dysfunction present with distressing shortness of breath, inspiratory stridor and breathy dysphonia. Occasionally symptoms may include expiratory stridor, coughing, dysphagia and excessive musculo skeletal tension [7]. VCD is most frequently diagnosed as asthma since the attacks in both begin and end suddenly and produce distressing breathing difficulties [8].
* Corresponding author at: Aly Ramez Street, No. 7, Ramleh station, Alexandria, Egypt. Tel.: +20 127435699. E-mail address: [email protected] (A.H. Gaafar). 1871-4048/$ – see front matter ß 2009 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.pedex.2009.12.002
The etiology of vocal cord dysfunction is not yet clear. The neurological explanation suggests that efferent motor vagal innervation is activated, producing a change in laryngeal muscle tone thus lowering threshold for stimuli to produce vocal cord spasm [9]. Many clinical reports described the presence of laryngeal irritation by post-nasal drip or gastroesophageal reflux as an etiology of vocal cord dysfunction [9,10]. The etiological importance of gastroesophageal reflux is supported by the clinical findings that anti-reflux drug therapy can lead to relief in paradoxical vocal cord movement [10]. A third possible explanation of the condition is that it represents a psychological conversion reaction. The abnormal laryngeal movement may serve the purpose of enabling the patient to avoid confrontation of an unpleasant life situation or emotion, and yields attention and sympathy [8,11]. The diagnosis of vocal cord dysfunction is not straightforward. Suspicions should be raised when the degree of dyspnea is out of proportion to the clinical signs and when there is little response to standard treatment [12]. The definitive diagnosis is made by indirect or fibreoptic laryngoscopy using only topical anesthesia during an acute episode. The characteristic appearance of adducted
14
A.H. Gaafar, N.A. Fasyh / International Journal of Pediatric Otorhinolaryngology Extra 6 (2011) 13–16
vocal cords with a posterior diamond-shaped chink is seen [11]. We represent cases of five children presented with vocal cord dysfunction secondary to different etiologies. Their diagnosis and management were discussed as well. 2. Material and methods This study was carried on at the Department of Otolaryngology Head & Neck Surgery and Department of Pediatric, Faculty of Medicine, Alexandria University, Egypt from January 2007 till January 2009. All infants and children presented with respiratory distress secondary to vocal cord dysfunction were included in this study. Diagnosis of VCD depended mainly on direct laryngoscopy either using flexible laryngoscopy with topical anesthesia or direct laryngoscopy under general anesthesia with spontaneous respiration. The typical finding of adduction of the anterior two-third of the vocal cords during inspiration was the key point for diagnosis of VCD. X-ray chest and tracheobronchoscopy were done to exclude other causes of airway obstruction. Further investigations were done according to the etiology of each case. 3. Results One infant and four children were included. They were three boys and two girls. Their ages were 1, 12, 14, 10 and 2 years. The etiology of VCD was bulbar myasthenia gravis in one case, multiple system atrophy in one case, laryngopharyngeal reflux in two cases, and postnasal drip in one case. Diagnosis of VCD was done using pediatric flexible fibreoptic laryngoscopy with topical anesthesia in two cases and by direct laryngoscopy under general anesthesia with spontaneous respiration in three cases (in one of them the vocal cords were visualized during urgent intubation). Three cases were receiving treatment of bronchial asthma with no improvement. 3.1. Case 1 One-year-old infant presented with recurrent attacks of respiratory distress and noisy breathing. The attack persists from few hours up to 2 days. Some times, difficulty in feeding was encountered. He was diagnosed previously as bronchial asthma, however, there was poor response to anti-asthma treatment. The parents gave history of previous baby who died at the age of 2 years from unknown neurological disease. Examination during the attack revealed moderate respiratory distress with no cyanosis, noisy breathing which was mainly inspiratory, retraction of suprasternal and intercostal spaces. Chest auscultation showed wheezy chest. X-ray chest was irrelevant and blood gases was within the normal levels. Direct laryngoscopy under general anesthesia with spontaneous respiration was done. It revealed the classical picture of vocal cord dysfunction with adduction of the anterior 2/3 and abduction of the posterior 1/3 of the vocal cords during inspiration (Fig. 1). Tracheobronchoscopy was irrelevant. Neostigmine test was done and it proved to be bulbar myasthenia gravis. The attacks of respiratory distress improved dramatically on myasthenia medication and plasmapheresis.
Fig. 1. Endoscopic picture of the larynx of case no. 1 (a) during inspiration showing adduction of the anterior two-third of the vocal cord with abduction of the posterior third and (b) during expiration showing abduction of the vocal cords.
bronchodilator and corticosteroids. These attacks increased gradually in time and intensity and it can occur at any time of the day. Also the parents noticed that she had abnormal gait, and mild imbalance since 18 months. X-ray chest, airway endoscopy and CT scan neck and chest all were free. Weaning of intubation failed and tracheostomy was done after 7 days. Neurological examination showed mild parkinsonism, left babinski sign, and severe dysautonomia. MRI brain showed posterior putamen hypointensity, atrophy of transverse fibres of the pons, the cerebellum, the middle cerebellar peduncles, and the inferior olives (Fig. 2). She was diagnosed as having multiple system atrophy (MSA). 3.3. Case 3 Fourteen-year-old boy presented with recurrent attacks of respiratory distress and apneic attacks which persists for few minutes. The attacks sometimes occur during sleep and the patient arose on the feeling of ‘‘Dying’’. During examination the patient developed an attack of difficult noisy breathing with suprasternal retraction. Flexible nasopharyngolaryngoscopy using pediatric flexible laryngoscope under topical anesthesia revealed the classical picture of vocal cord dysfunction. In addition, the larynx
3.2. Case 2 Twelve-year-old girl presented to the emergency department by severe respiratory distress and cyanosis. Urgent intubation was done. During intubation the vocal cords were visualized showing adduction of the anterior two-third during inspiration. The parents stated that their daughter started to complaint of attacks of respiratory difficulty mainly at night since 2 years. It was diagnosed as bronchial asthma with no improvement on
Fig. 2. MRI Sagittal T1-weighted image of case no. 2 with multiple system atrophy demonstrates atrophy of transverse fibres of the pons, the cerebellum, the middle cerebellar peduncles, and the inferior olives (arrow).
A.H. Gaafar, N.A. Fasyh / International Journal of Pediatric Otorhinolaryngology Extra 6 (2011) 13–16
and the upper trachea showed diffuse congestion mainly at the posterior part with oedema over both arytenoids. X-ray chest, blood gases and MRI brain all were free. The case was diagnosed as reflux laryngitis. The patient responded well to anti-reflux treatment and the attacks of respiratory distress disappeared. 3.4. Case 4 Ten-year-old boy presented with recurrent attacks of respiratory distress since 4 years. The attack persisted for few hours. Examination of the child during the attack showed tachypnea, change of voice, flushed face, wheezy chest, suprasternal retraction. X-ray chest and blood gases were irrelevant. The patient was diagnosed as a case of bronchial asthma. There was poor response to anti-asthma treatment with subsequent increase in the dose of corticosteroids, however, with no improvement in the frequency or intensity of the attacks. Flexible nasopharyngolaryngoscopy under local anesthesia was planned to visualize the airway. During the endoscopy the child developed an attack of distress with immediate change in the movement of the vocal cords from the normal pattern into abnormal adduction of the anterior two-thirds during inspiration. Except from mild congestion in the posterior parts of the arytenoids, the larynx and the trachea were free. The patient received anti-reflux treatment in conjunction with antiasthma treatment with subsequent improvement in the frequency and intensity of the attacks. 3.5. Case 5 Two-year-old girl presented with snoring, nocturnal coughing and attacks of prolonged irritating cough followed by noisy breathing and respiratory distress for few minutes. The condition started following severe attack of upper respiratory tract infection since 2 months. Examination during the attack revealed respiratory distress with inspiratory sound, suprasternal and intercostals retraction and scattered ronchi on the chest. Local examination revealed rhinitis, post-nasal discharge and congested posterior pharyngeal wall. X-ray nasopharynx showed adenoid hypertrophy. X-ray chest was free. The condition improved partially on antibiotic and nasal decongestant therapy. Decision of adenoidectomy was done. During induction of anesthesia the larynx was visualized using the nasal endoscope zero degree, 4 mm and it revealed the classical picture of vocal cord dysfunction. After adenoidectomy the condition was totally improved. 4. Discussion Vocal cord dysfunction is a well-recognized respiratory condition in which active adduction of the vocal cords during inspiration causes functional airway obstruction [13]. VCD has been described in adults and children. While VCD mostly occurs in females aged 20–40 years [4], we report one infant and 4 children with VCD, three of them were boys. The ages of our patients were 1, 12, 14, 10, and 2 years. Previous reports stated that VCD in children occurs most commonly in age of 10–15 years [14,15], and less commonly it can occur in infants [16,17]. Diagnosis of VCD is done by visualizing the vocal cords during the attack using flexible laryngoscopy under topical anesthesia [11]. In pediatric age group, this will not be feasible in every case. Infants and uncooperative child will be obstacle for diagnosis using flexible laryngoscopy. In our cases we were able to diagnose two out of five patients using flexible laryngoscopy under topical anesthesia. The other three cases were diagnosed under general anesthesia with spontaneous respiration. We found that the nasal endoscope zero degree, 4 mm in diameter is very practical in diagnosis of laryngeal anomalies under general anesthesia. Its
15
length and diameter provide good quality image. Also, digital video camera could be attached to record any abnormal movement in the larynx. Beside laryngoscopy, other measures for directly assessing dysfunction of the vocal cords have been reported in the literature, such as computerized laryngeal ultrasound investigations, which have the advantage of being non-invasive, painless and widely accepted [33]. However, this technique requires experience which cannot be obtained in most centers. The etiology of VCD in our patients was bulbar myasthenia gravis in one patient, multiple system atrophy in one patient, laryngopharyngeal reflux in two patients and post-nasal drip in one patient. Myasthenia gravis is an acquired disorder of the neuromuscular junction caused by antibodies against the acetylcholine receptor of the striated muscle endplate [18]. Muscles innervated by cranial nerves (bulbar muscles) are usually the first and most seriously involved in myasthenia gravis causing ptosis, dysphagia, dysarthria and dysphonia [19]. Respiratory impairment in myasthenia gravis is usually attributed to weakness of the diaphragm and other muscles that move the chest wall [20]. However, another cause of respiratory impairment in myasthenia gravis is upper airway obstruction. Schmidt et al. [20] and Marlowe et al. [21] sated that the most important dysfunction of the upper airway leading to respiratory failure is laryngeal muscle weakness causing abnormal adduction of the vocal cords. In our case, diagnosis of bulbar myasthenia gravis was suspected due to the association of ptosis and generalized weakness and after exclusion of other causes of VCD. It was proved by neostigmine test. The condition improved on anticholinesterase and plasmapheresis. Maryann and Robert in 1996 [22] reported five children with myasthenia gravis presented with upper airway obstruction secondary to laryngeal dysfunction, all of them improved on myasthenia medication. Multiple system atrophy is a neurodegenerative disorder causing various combinations of systemic degeneration in the cerebellar, extrapyramidal and autonomic systems. Nocturnal stridor and selective paralysis of the vocal cord abductor frequently develop in MSA patients [23,24]. It had been thought that the MSA-related stridor results from passive glottis narrowing attributed to both abductor paralysis and the Bernoulli effect causing collapse of the vocal cords during inspiration [13]. However, electromyographic studies during sleep showed that the vocal cord adductor is activated during inspiration when the characteristic stridor develop in MSA patients. Therefore, the MSA related laryngeal stridor depends on active glottis narrowing as well as passive narrowing [25,26]. In our case, the typical nocturnal stridor at the beginning with the associated neurological manifestations suggested the diagnosis of MSA. This was confirmed by the radiological signs in the form of atrophy of transverse fibres of the pons, the cerebellum, the middle cerebellar peduncles, and the inferior olives in MRI T1-weighted image [27]. Brancatisano and Engel [28] have speculated in their review published in 1988 that some laryngeal reflexes contribute to generation of VCD. A similar concept has recently been postulated giving the name; the irritable larynx syndrome [3,29]. It stated that laryngeal closure reflex is augmented in patients with VCD such that various extrinsic and intrinsic stimuli can trigger reflective glottis closure as an adaptive protective response, and these laryngeal stimulus conditions lower the threshold levels for the initiation of glottis closure reflex. VCD frequently develops after laryngeal irritation including infections of the upper respiratory tract [10], gastroesophageal reflux disease [29], inhaled irritant exposure and strong odors [30], post-nasal drip [10] and thyroid surgery [31]. In our cases, three out of five were secondary to laryngeal irritation, two cases secondary to gastroesophageal reflux and one secondary to upper respiratory tract infection and
16
A.H. Gaafar, N.A. Fasyh / International Journal of Pediatric Otorhinolaryngology Extra 6 (2011) 13–16
post-nasal drip. Elimination of the irritating factor improved the condition dramatically. Vocal cord dysfunction is prone to being misdiagnosed as asthma owing to its asthma-like symptoms such as stridorous wheezing and dyspnea [13]. Nigemann et al. reported VCD in three children which were misdiagnosed as bronchial asthma. In our cases, three out of five children were misdiagnosed as bronchial asthma. Therefore, unnecessary anti-asthma treatments were administrated. When children with VCD are given diagnosis of asthma, physicians are prone to conduct unnecessary aggressive therapy including high dose of corticosteroids with no significant improvement [32]. It is important for physicians to know that patients with steroid-resistant asthma may have VCD and to diagnose VCD correctly based on the mechanism of its development. Many factors can differentiate asthma from VCD including that dyspnea is mainly inspiratory, no or marginal response to bronchodilator and corticosteroids, variable flattening of the inspiratory limb of the flow-volume curve, and finally the classical endoscopic picture of the vocal cords during the attack [14]. 5. Conclusion Vocal cord dysfunction represents a potentially overlooked differential diagnosis of recurrent dyspnea in children. It is always misdiagnosed as bronchial asthma. It should be suspected in every child with atypical or corticosteroid resistant asthma. Definite diagnosis is done by direct visualization of the larynx during the attack using flexible laryngoscopy under topical anesthesia. In uncooperative child, the larynx could be visualized under general anesthesia with spontaneous respiration. References [1] R.M. Kellman, D.A. Leopold, Paradoxical vocal cord motion: an important cause of stridor, Laryngoscope 92 (1982) 58–60. [2] M.V. Andrianopoulos, G.J. Gallivan, K.H. Gallivan, PVCM, PVCD, EPL, and irritable larynx syndrome: what are we talking about and how do we treat it? J. Voice 14 (2000) 607–618. [3] K.W. Altman, C.B. Simpson, M.R. Amin, M. Abaza, R.R. Casiano, Cough and paradoxical vocal fold motion, Otolaryngol. Head Neck Surg. 127 (2002) 501–511. [4] T.J. Lacy, S.E. Mcmanis, Psychogenic stridor, Gen. Hosp. Psych. 16 (1994) 213–223. [5] G.H. Rogers, Functional inspiratory stridor in children, J. Laryngol. Otol. 94 (1980) 669–670. [6] M. Kattan, Z. Ben-Zvi, Stridor caused by vocal cord malfunction 24 (1985) 158– 160. [7] L. Sette, F. Pajno-Ferrara, S. Mocella, Vocal cord dysfunction in an asthmatic child: case report, J. Asthma 30 (1993) 407–412. [8] J. Corren, K.B. Newman, Vocal cord dysfunction mimicking bronchial asthma, Postgrad. Med. 92 (1992) 153–156.
[9] G.J. Gallivan, L. Hoffman, K.H. Gallivan, Episodic paroxysmal laryngospasm: voice and pulmonary function assessment, J. Voice 10 (1996) 93–105. [10] A.H. Campbell, H. Mestitz, R. Pierce, Brief upper airway (laryngeal) dysfunction, Aust. N.Z. J. Med. 20 (1990) 663–668. [11] K.L. Christopher, R.P. Wood, R.C. Eckert, Vocal cord dysfunction presenting as asthma, New Engl. J. Med. 308 (1983) 1566–1570. [12] D.M. Murray, P.G. Lawler, All that wheezes is not asthma, paradoxical vocal cord movement presenting as severe acute asthma requiring ventilator support. Case report, Anesthesia 53 (1998) 1002–1011. [13] S. Keisuke, I. Shiroh, N. Ken, Paradoxical vocal cord motion: a review focused on multiple system atrophy, Auris. Nasus Larynx 34 (2007) 443–452. [14] B. Niggemann, K. Paul, R. Keitzer, U. Wahn, Vocal cord dysfunction in three children—misdiagnosis of bronchial asthma? Ped. Allerg. Immunol. 9 (1998) 97–100. [15] S.E. Alpert, D.G. Dearaborn, C.M. Kercsmar, On vocal cord dysfunction in wheezy children, Ped. Pulmonol. 142 (1991) 142–143. [16] M.J. Cunningham, R.D. Eavey, D.C. Shannon, Familial vocal cord dysfunction, Pediatrics 76 (1995) 750–753. [17] D.G. Heatley, E. Swift, Paradoxical vocal cord dysfunction in an infant with stridor and gastroesophageal reflux, Int. J. Ped. Otolaryngol. 34 (1996) 149–151. [18] D.R. Grancey, F.M. Howard, M.B. Divertie, Plasmapheresis in the treatment of ventilator-dependent myasthenia gravis patients, Chest 85 (1984) 739–743. [19] J.J. Zulueta, B.L. Fanburg, Respiratory dysfunction in myasthenia gravis, Clin. Chest Med. 15 (1994) 683–691. [20] W.W. Schmidt-Nowara, E.J. Marder, P.A. Feil, Respiratory failure in myasthenia gravis due to vocal cord paresis, Arch. Neurol. 41 (1984) 567–568. [21] F.I. Marlowe, A.J. D’Angelo, Respiratory failure as the initial presentation of myasthenia gravis, Ear Nose Throat J. 68 (1989) 472–473. [22] T.P. Maryann, A.W. Robert, Myasthenia gravis and upper airway obstruction, Hest 109 (1996) 400–404. [23] R. Bannister, W. Gibson, L. Michaels, D.R. Oppenheimer, Laryngeal abductor paralysis in multiple system atrophy, Brain 104 (1981) 351–368. [24] A. Williams, D. Hanson, D. Calne, Vocal cord paralysis in the Shy-Drager syndrome, J. Neurol. Neurosurg. Psychiatry 42 (1979) 151–153. [25] S. Isono, K. Shiba, M. Yamaguchi, A. Tanaka, T. Hattori, A. Konno, Pathogenesis of laryngeal narrowing in patients with multiple system atrophy, J. Physiol. 536 (2001) 237–249. [26] E. Isozaki, R. Osanai, S. Horiguchi, T. Hayashida, K. Hirose, H. Tanabe, Laryngeal electromyography with separated surface electrodes in patients with multiple system atrophy presenting with vocal cord paralysis, J. Neurol. 241 (1994) 551– 556. [27] E. Kraft, J. Schwarz, C. Tenkwalder, T. Vogl, The combination of hypointense and hyperintense signal changes on T2-weighted magnetic resonance imaging sequences: a specific marker of multiple system atrophy? Arch. Neurol. 56 (1999) 225–228. [28] A. Brancatisano, L.A. Engel, Role of upper respiratory airway in the control of respiratory flow and lung volume in humans, in: O.P. Mathew, G. Sant’s Ambrogio (Eds.), Respiratory Function of the Upper Airway, Marcel Dekker, New York, 1988, pp. 447–517. [29] M. Morrison, L. Rammage, A.J. Emami, The irritable larynx syndrome, J. Voice 12 (1999) 447–455. [30] J.J. Perkner, K.P. Fennelly, R. Balkissoon, B.B. Bartelson, A.J. Ruttenber, Irritantassociated vocal cord dysfunction, J. Occup. Environ. Med. 40 (1998) 136–143. [31] J. Harbison, J. Dodd, W.T. McNicholas, Paradoxical vocal cord motion causing stridor after thyroidectomy, Thorax 55 (2000) 533–534. [32] K.B. Newman, U.G. Mason, K.B. Schmaling, Clinical features of vocal cord dysfunction, Am. J. Respir. Crit. Care Med. 152 (1995) 1382–1386. [33] E.M. Friedman, Role of ultrasound in assessment of vocal cord dysfunction in infants and children, Ann. Otol. Rhinol. Laryngol. 196 (1997) 199–209.