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Intermittent stridor and dyspnea in an adult
Clinical allergy-immunology rounds Supported by an unrestricted grant from Aventis Pharmaceuticals
Intermittent stridor and dyspnea in an adult ´ ngeles Gonzalo-Garijo, MD*; and Vicente Albe´ndiz-Ruiz, MD† Remedios Pe´rez-Caldero´n, MD*; M. A
CHIEF COMPLAINT A 2-year history of recurrent episodes of cough, dyspnea, and stridor. HISTORY OF PRESENT ILLNESS A 55-year-old woman had a 2-year history of recurrent episodes of cough, dyspnea, and stridor, which persisted for approximately 5 to 10 minutes. The cough was related to some positions, such as hyperextension of the neck. The symptoms resolved spontaneously. She had no known allergies and had no history of drug or food reactions or contact hypersensitivity. No relationships were apparent between her dietary habits, work-related factors, or hobbies and her symptoms. No provocative factors, such as cold, sunlight, physical exercise, or infection, could be identified by patient history or laboratory testing. PERSONAL AND FAMILY HISTORY The patient denied having any gastrointestinal, respiratory, cardiology, or endocrine disorders. She had been hospitalized for tonsillectomy, adenoidectomy, dilation and curettage, hysterectomy, and management of inguinal hernia. She smokes 40 cigarettes daily. There was no family history of angioedema, atopy, eczema, immunodeficiency disorders, autoimmune diseases, or neurologic conditions. PHYSICAL EXAMINATION Physical examination revealed an obese woman with a short, thick neck. On palpation, no mass was evident in her neck. Examination of the mouth and oral cavity failed to disclose abnormalities. The nose, ears, throat, and eyes were normal. No adenopathy was noted. The lungs were clear to auscultation. The patient had no physical signs referable to the cardiac, neurologic, or gastrointestinal system and no evidence of hepatosplenomegaly. LABORATORY AND DIAGNOSTIC STUDIES Skin testing to inhalant allergens (pollens, mites, fungi, latex, and cat and dog dander) and food allergens (cow’s milk, eggs, * Allergology Department, Infanta Cristina University Hospital, Badajoz, Spain. † Centro de Salud La Paz, Badajoz, Spain. Received for publication February 4, 2001. Accepted for publication in revised form February 22, 2002.
294
cereal grains, nuts, fish, meat, crustaceans, mollusks, and fruits) was negative. A tuberculin skin test (with purified protein derivative) was also negative. Laboratory investigation revealed normal results of the following: complete blood cell count and differential, erythrocyte sedimentation rate, urinalysis, biochemical studies (liver and renal function tests and electrolytes), coagulation studies, thyroid hormones, antithyroid antibodies, quantitative serum immunoglobulins, immune complexes, complement studies (C3, C4, CH50, and C1 inhibitor), protein electrophoresis, C-reactive protein, antistreptolysin, rheumatoid factor, and antinuclear antibodies. X-ray studies of the sinuses and thorax showed normal findings. DIFFERENTIAL DIAGNOSIS: QUESTIONS 1. On the basis of the history, physical examination, and foregoing laboratory results, what should be included in the differential diagnosis? A. Asthma B. Foreign body C. Extrinsic compression of the airways by a tumor, goiter, or other lesion D. Infections involving the upper respiratory tract E. Angioedema F. Vocal cord dysfunction 2. What further diagnostic studies are needed to confirm the final diagnosis? A. Laryngoscopy B. Spirometry with flow-volume loops C. Lateral neck radiography D. Computed tomography of the neck E. Scintigraphic imaging with 99mTc DIFFERENTIAL DIAGNOSIS: ANSWERS Examination of the larynx of the patient with the flexible fiber optic laryngoscope was not possible because the patient declined to undergo this procedure. Pulmonary function tests (spirometry with flow-volume loops) showed a cutoff of the inspiratory peak in conjunction with normal expiratory measurements. No improvement was obtained during an interval of a few minutes after inhalation of salbutamol. Lateral neck radiography disclosed a 4-cm mass in the superoanterior cervical area, which caused substantial obstruction of the airway at the level of the epiglottis (Fig 1).
ANNALS OF ALLERGY, ASTHMA, & IMMUNOLOGY
Scintigraphic imaging with 99mTc showed a notable deposit of radiotracer in the mandibular midline between submaxillary salivary glands, without radioisotope trapping in the area of the thyroid gland. FURTHER DIAGNOSTIC STUDIES AND CLINICAL COURSE With the patient under general anesthesia, the mass was removed together with the hyoid bone (Sistrunk procedure). Histologic findings were compatible with a thyroglossal duct cyst with ectopic thyroid tissue. After the operation, the patient began treatment with thyroid hormones. The dyspnea and stridor disappeared, and the spirometric flow-volume curves were normal (Fig 3). The patient had no postoperative complications and no recurrence of the cyst during a 2-year followup period.
Figure 1. Lateral radiographic view of neck of study patient, demonstrating superoanterior cervical mass.
DISCUSSION Among conditions that may masquerade as asthma, disorders of the larynx are often troubling to the clinician and are commonly misdiagnosed. Patients with such disorders may complain of shortness of breath, which may be accompanied by “wheezing” and cough; other patients indicate that their symptoms are worsened by exercise. Stridor implies partial obstruction of the airways, resulting from intrinsic or extrinsic abnormalities of the upper respiratory tract. Direct visualization of the larynx at the time a patient is experiencing
Ultrasound examination of the neck identified a blurred image of the thyroid in association with a nodule (approximately 5 cm) in the right thyroid lobe. Computed tomography of the neck revealed a midline mass from the floor of the mouth to the anterior and medial supraglottic area. It obliterated fatty planes and extended to the left side of the supraglottis, epiglottic vallecula, and piriform sinus (Fig 2).
Figure 2. Computed tomographic scan of neck area of study patient, revealing extensive midline mass.
VOLUME 90, MARCH, 2003
Figure 3. Spirometry with flow-volume (FV) loops, showing preoperative and postoperative results in 55-year-old study patient.
295
symptoms is the diagnostic approach of highest yield in most laryngeal disorders.1 In an adult, the differential diagnosis of stridor and dyspnea includes both infectious and noninfectious processes affecting the upper airways (Table 1).1,2 Epiglottitis is one of the most rapidly developing and frightening infectious causes of dyspnea originating in the larynx. Bacterial infections of the trachea can also occur. Initial manifestations may include high fever, stridor, a barking cough, extreme leukocytosis, and a thick mucopurulent discharge from the trachea. Laryngeal abscesses may also compromise the airway and necessitate surgical incision and drainage. They may slowly increase in severity and may follow previous episodes of tonsillar infections. In addition,
Table 1. Differential Diagnosis of Stridor and Dyspnea in an Adult Structural interference with airflow Infectious causes Epiglottitis Tracheitis Laryngeal abscess Tuberculosis Syphilis Diphtheria Trichinosis Leprosy Fungus: Aspergillus, Candida, Histoplasma, Coccidioides, Blastomyces, Actinomyces, Cryptococcus, and Nocardia Virus: croup (influenza and parainfluenza), cytomegalovirus (congenital and human immunodeficiency virus-related disease), human papillomavirus (producing laryngeal papillomatosis) Noninfectious causes Congenital laryngomalacia Subglottic stenosis Anatomic disruption because of trauma Inflammatory or vasculitic conditions Amyloidosis Sarcoidosis Relapsing polychondritis Systemic lupus erythematosus Tumor Ingestion of lye or acid Acute allergic reactions (laryngeal edema) Thermal or chemical inhalation Foreign body aspiration Vocal cord polyps Laryngocele Saccular cyst Laryngeal vascular lesions Extrinsic laryngeal compression (for example, substernal goiter) Abnormal movement of laryngeal structures Paradoxic vocal cord motion (vocal cord dysfunction) Vocal cord paralysis (unilateral or bilateral) Laryngospasm Meige syndrome (neurologic condition accompanied by episodic spastic closure of the true vocal cords) Spastic dysphonia
296
other infectious diseases may involve the upper respiratory tract, including tuberculosis, syphilis, diphtheria, trichinosis, leprosy, histoplasmosis, and fungal and viral infections. Clinical and laboratory findings in our patient were not typical for any of these possible infections. Many noninfectious processes affecting the upper airways may interfere with appropriate airflow. Laryngomalacia, a congenital condition that results from flaccidity of the larynx, occurs as a result of lack of rigidity of the framework supporting the larynx. Symptoms usually occur in infants and young children; they may manifest a few weeks after birth and last from 12 to 18 months. The diagnosis is confirmed when direct visualization of the larynx discloses a convergence of the laryngeal structures during inspiration. Subglottic stenosis may occur because of trauma to the larynx (such as that caused by prolonged endotracheal intubation), certain inflammatory or vasculitic conditions (such as Wegener granulomatosis, relapsing polychondritis, or systemic lupus erythematosus), tumor, thermal or chemical inhalation, and ingestion of lye or acid. Amyloidosis and sarcoidosis may also rarely cause inflammatory masses or other inflammatory changes in the larynx. In addition, acute allergic reactions may cause laryngeal edema. Foreign body aspiration should always be considered in young children with dyspnea. Likewise, foreign body aspiration may occur in elderly patients— especially those who are debilitated or have swallowing malfunction as a result of musculoskeletal disorders, stroke, or other factors. Interestingly, if the aspiration does not precipitate immediate symptoms, it might cause an inflammatory and granulomatous reaction responsible for symptoms later (even when the patient may have forgotten the aspiration). Both benign and malignant neoplasms of the larynx, vocal cord disorders (polyps, dysfunction, or paralysis), laryngocele, saccular cysts, laryngeal vascular lesions, and cervical and substernal goiters may obstruct the upper airways.1,2 In our patient, the diagnosis of subglottic stenosis could have been considered because the patient had undergone endotracheal intubation three times. On the basis of the information provided by the imaging studies, the differential diagnosis should include the following midline neck masses: dermoid cyst, sebaceous cyst, benign or malignant lymphadenopathy, lipoma, pyramidal lobe of thyroid, thyroid adenoma or carcinoma, goiter, aberrant thyroid tissue, salivary gland tumor, branchial cleft cyst, laryngocele, teratoma, and thyroglossal duct cyst.2 After performance of radiographic studies, we suspected the diagnosis of thyroglossal duct cyst in our patient. This presumptive diagnosis was confirmed by histologic examination of the surgical specimen. CONCLUSION Thyroglossal duct cyst occurs most commonly in children, but it can also manifest in adults, even in elderly persons. The cyst is always localized to the medial area of the neck, most often beside the lingual bone. In most patients, the first symptom of this condition is a painless lump in the neck; less
ANNALS OF ALLERGY, ASTHMA, & IMMUNOLOGY
frequently, the patient may have difficulty in swallowing and signs of infection (pain, redness, and swelling of the neck).3–5 We report a case of a thyroglossal duct cyst in an adult patient; it caused stridor and dyspnea as the initial symptoms. The thyroglossal duct cyst is the most common congenital neck mass, resulting from persistence and dilatation of remnants of an epithelial tract formed during migration of the thyroid during embryogenesis. Thyroglossal duct remnants are present in approximately 7% of the population. Although thyroglossal duct cysts generally manifest clinically in children, it is important to be aware that the lesion can occur in adults as well—sometimes late in life. Incidental carcinoma of the thyroglossal duct cyst is rare, but is more likely to occur in adults than in children.3–5 A thyroglossal duct cyst rarely induces dyspnea and stridor in adults. A MEDLINE search for articles on this subject published between 1966 and November 2001 disclosed only two reports (one in Japanese and the other in German).6,7 For the diagnosis of thyroglossal duct cyst, physical examination (inspection and palpation) of the neck and confirmation by thyroid ultrasonography and computed tomography of the neck are generally sufficient. Thyroid scintigraphy is primarily used preoperatively to demonstrate normal thyroid tissue. This procedure is believed to reduce the risk of postoperative hypothyroidism attributable to inadvertent removal of the only functioning thyroid tissue present within the thyroglossal duct cyst. Some physicians recommend thyroid scanning in all patients with thyroglossal duct cyst, whereas others advocate scintigraphy only when the cyst is present at the base of the tongue (because of the presence of ectopic thyroid tissue in 1 to 2% in such cases).3–5 For consideration of causes of dyspnea, pulmonary function tests (spirometry with flow-volume loops) are helpful and provide objective measurements of airflow obstruction. The configuration of the forced expiratory-inspiratory flowvolume loop can provide clues in the differential diagnosis of asthma and complicating conditions. In patients with variable extrathoracic airway obstruction, cutoff of the inspiratory peaks is evident. Improvement of spirometric findings during a period of a few minutes after inhalation of a -adrenergic bronchodilator reflects the component of bronchospasm in airway obstruction. Spirometry is appropriate for monitoring
VOLUME 90, MARCH, 2003
the course of disease and the response to therapy.8 In our patient, this technique provided useful information for the diagnosis and the postoperative followup. SUMMARY We describe an adult patient who had stridor and dyspnea as initial symptoms of a thyroglossal duct cyst. Spirometry and noninvasive imaging techniques have been useful for diagnosis of this condition. REFERENCES 1. O’Hollaren MT. Dyspnea originating from the larynx. Immunol Allergy Clin North Am 1996;16:69 –76. 2. Shepherd S, Geraci SA. The differential diagnosis of dyspnea: a pathophysiologic approach. Clin Rev 1999;9:52–54,59 – 61,65– 66,71–74. 3. Josephson GD, Spencer WR, Josephson JS. Thyroglossal duct cyst: the New York Eye and Ear Infirmary experience and a literature review. Ear Nose Throat J 1998;77:642– 644,646 – 647,651. 4. Ewing CA, Kornblut A, Greeley C, Manz H. Presentations of thyroglossal duct cysts in adults. Eur Arch Otorhinolaryngol 1999;256:136 –138. 5. Katz AD, Hachigian M. Thyroglossal duct cysts. A thirty year experience with emphasis on occurrence in older patients. Am J Surg 1988;155:741–744. 6. Honig M, Taake S, Hormann K. Mouth floor cyst with increasing dyspnea. Thyroglossal duct cyst in the area of the mouth floor [in German]. HNO 2000;48:398 –399. 7. Kobayashi M. A large thyroglossal duct cyst induced dyspnea in a 94-year-old patient. Otolaryngol Head Neck Surg 1996;68: 222–225. 8. Mathison DA. Asthma in adults: evaluation and management. In: Middleton E Jr, Reed CE, Ellis EF, et al, editors. Allergy: Principles and Practice. Vol 2. 5th ed. St Louis, MO: Mosby, 1998:904 –906. Requests for reprints should be addressed to: Dra. M. A´ngeles Gonzalo-Garijo Servicio de Alergologı´a Hospital Universitario Infanta Cristina Carretera de Portugal s/n 06080 Badajoz, Spain E-mail: [email protected]
297
Intermittent stridor and dyspnea in an adult ´ ngeles Gonzalo-Garijo, MD*; and Vicente Albe´ndiz-Ruiz, MD† Remedios Pe´rez-Caldero´n, MD*; M. A
CHIEF COMPLAINT A 2-year history of recurrent episodes of cough, dyspnea, and stridor. HISTORY OF PRESENT ILLNESS A 55-year-old woman had a 2-year history of recurrent episodes of cough, dyspnea, and stridor, which persisted for approximately 5 to 10 minutes. The cough was related to some positions, such as hyperextension of the neck. The symptoms resolved spontaneously. She had no known allergies and had no history of drug or food reactions or contact hypersensitivity. No relationships were apparent between her dietary habits, work-related factors, or hobbies and her symptoms. No provocative factors, such as cold, sunlight, physical exercise, or infection, could be identified by patient history or laboratory testing. PERSONAL AND FAMILY HISTORY The patient denied having any gastrointestinal, respiratory, cardiology, or endocrine disorders. She had been hospitalized for tonsillectomy, adenoidectomy, dilation and curettage, hysterectomy, and management of inguinal hernia. She smokes 40 cigarettes daily. There was no family history of angioedema, atopy, eczema, immunodeficiency disorders, autoimmune diseases, or neurologic conditions. PHYSICAL EXAMINATION Physical examination revealed an obese woman with a short, thick neck. On palpation, no mass was evident in her neck. Examination of the mouth and oral cavity failed to disclose abnormalities. The nose, ears, throat, and eyes were normal. No adenopathy was noted. The lungs were clear to auscultation. The patient had no physical signs referable to the cardiac, neurologic, or gastrointestinal system and no evidence of hepatosplenomegaly. LABORATORY AND DIAGNOSTIC STUDIES Skin testing to inhalant allergens (pollens, mites, fungi, latex, and cat and dog dander) and food allergens (cow’s milk, eggs, * Allergology Department, Infanta Cristina University Hospital, Badajoz, Spain. † Centro de Salud La Paz, Badajoz, Spain. Received for publication February 4, 2001. Accepted for publication in revised form February 22, 2002.
294
cereal grains, nuts, fish, meat, crustaceans, mollusks, and fruits) was negative. A tuberculin skin test (with purified protein derivative) was also negative. Laboratory investigation revealed normal results of the following: complete blood cell count and differential, erythrocyte sedimentation rate, urinalysis, biochemical studies (liver and renal function tests and electrolytes), coagulation studies, thyroid hormones, antithyroid antibodies, quantitative serum immunoglobulins, immune complexes, complement studies (C3, C4, CH50, and C1 inhibitor), protein electrophoresis, C-reactive protein, antistreptolysin, rheumatoid factor, and antinuclear antibodies. X-ray studies of the sinuses and thorax showed normal findings. DIFFERENTIAL DIAGNOSIS: QUESTIONS 1. On the basis of the history, physical examination, and foregoing laboratory results, what should be included in the differential diagnosis? A. Asthma B. Foreign body C. Extrinsic compression of the airways by a tumor, goiter, or other lesion D. Infections involving the upper respiratory tract E. Angioedema F. Vocal cord dysfunction 2. What further diagnostic studies are needed to confirm the final diagnosis? A. Laryngoscopy B. Spirometry with flow-volume loops C. Lateral neck radiography D. Computed tomography of the neck E. Scintigraphic imaging with 99mTc DIFFERENTIAL DIAGNOSIS: ANSWERS Examination of the larynx of the patient with the flexible fiber optic laryngoscope was not possible because the patient declined to undergo this procedure. Pulmonary function tests (spirometry with flow-volume loops) showed a cutoff of the inspiratory peak in conjunction with normal expiratory measurements. No improvement was obtained during an interval of a few minutes after inhalation of salbutamol. Lateral neck radiography disclosed a 4-cm mass in the superoanterior cervical area, which caused substantial obstruction of the airway at the level of the epiglottis (Fig 1).
ANNALS OF ALLERGY, ASTHMA, & IMMUNOLOGY
Scintigraphic imaging with 99mTc showed a notable deposit of radiotracer in the mandibular midline between submaxillary salivary glands, without radioisotope trapping in the area of the thyroid gland. FURTHER DIAGNOSTIC STUDIES AND CLINICAL COURSE With the patient under general anesthesia, the mass was removed together with the hyoid bone (Sistrunk procedure). Histologic findings were compatible with a thyroglossal duct cyst with ectopic thyroid tissue. After the operation, the patient began treatment with thyroid hormones. The dyspnea and stridor disappeared, and the spirometric flow-volume curves were normal (Fig 3). The patient had no postoperative complications and no recurrence of the cyst during a 2-year followup period.
Figure 1. Lateral radiographic view of neck of study patient, demonstrating superoanterior cervical mass.
DISCUSSION Among conditions that may masquerade as asthma, disorders of the larynx are often troubling to the clinician and are commonly misdiagnosed. Patients with such disorders may complain of shortness of breath, which may be accompanied by “wheezing” and cough; other patients indicate that their symptoms are worsened by exercise. Stridor implies partial obstruction of the airways, resulting from intrinsic or extrinsic abnormalities of the upper respiratory tract. Direct visualization of the larynx at the time a patient is experiencing
Ultrasound examination of the neck identified a blurred image of the thyroid in association with a nodule (approximately 5 cm) in the right thyroid lobe. Computed tomography of the neck revealed a midline mass from the floor of the mouth to the anterior and medial supraglottic area. It obliterated fatty planes and extended to the left side of the supraglottis, epiglottic vallecula, and piriform sinus (Fig 2).
Figure 2. Computed tomographic scan of neck area of study patient, revealing extensive midline mass.
VOLUME 90, MARCH, 2003
Figure 3. Spirometry with flow-volume (FV) loops, showing preoperative and postoperative results in 55-year-old study patient.
295
symptoms is the diagnostic approach of highest yield in most laryngeal disorders.1 In an adult, the differential diagnosis of stridor and dyspnea includes both infectious and noninfectious processes affecting the upper airways (Table 1).1,2 Epiglottitis is one of the most rapidly developing and frightening infectious causes of dyspnea originating in the larynx. Bacterial infections of the trachea can also occur. Initial manifestations may include high fever, stridor, a barking cough, extreme leukocytosis, and a thick mucopurulent discharge from the trachea. Laryngeal abscesses may also compromise the airway and necessitate surgical incision and drainage. They may slowly increase in severity and may follow previous episodes of tonsillar infections. In addition,
Table 1. Differential Diagnosis of Stridor and Dyspnea in an Adult Structural interference with airflow Infectious causes Epiglottitis Tracheitis Laryngeal abscess Tuberculosis Syphilis Diphtheria Trichinosis Leprosy Fungus: Aspergillus, Candida, Histoplasma, Coccidioides, Blastomyces, Actinomyces, Cryptococcus, and Nocardia Virus: croup (influenza and parainfluenza), cytomegalovirus (congenital and human immunodeficiency virus-related disease), human papillomavirus (producing laryngeal papillomatosis) Noninfectious causes Congenital laryngomalacia Subglottic stenosis Anatomic disruption because of trauma Inflammatory or vasculitic conditions Amyloidosis Sarcoidosis Relapsing polychondritis Systemic lupus erythematosus Tumor Ingestion of lye or acid Acute allergic reactions (laryngeal edema) Thermal or chemical inhalation Foreign body aspiration Vocal cord polyps Laryngocele Saccular cyst Laryngeal vascular lesions Extrinsic laryngeal compression (for example, substernal goiter) Abnormal movement of laryngeal structures Paradoxic vocal cord motion (vocal cord dysfunction) Vocal cord paralysis (unilateral or bilateral) Laryngospasm Meige syndrome (neurologic condition accompanied by episodic spastic closure of the true vocal cords) Spastic dysphonia
296
other infectious diseases may involve the upper respiratory tract, including tuberculosis, syphilis, diphtheria, trichinosis, leprosy, histoplasmosis, and fungal and viral infections. Clinical and laboratory findings in our patient were not typical for any of these possible infections. Many noninfectious processes affecting the upper airways may interfere with appropriate airflow. Laryngomalacia, a congenital condition that results from flaccidity of the larynx, occurs as a result of lack of rigidity of the framework supporting the larynx. Symptoms usually occur in infants and young children; they may manifest a few weeks after birth and last from 12 to 18 months. The diagnosis is confirmed when direct visualization of the larynx discloses a convergence of the laryngeal structures during inspiration. Subglottic stenosis may occur because of trauma to the larynx (such as that caused by prolonged endotracheal intubation), certain inflammatory or vasculitic conditions (such as Wegener granulomatosis, relapsing polychondritis, or systemic lupus erythematosus), tumor, thermal or chemical inhalation, and ingestion of lye or acid. Amyloidosis and sarcoidosis may also rarely cause inflammatory masses or other inflammatory changes in the larynx. In addition, acute allergic reactions may cause laryngeal edema. Foreign body aspiration should always be considered in young children with dyspnea. Likewise, foreign body aspiration may occur in elderly patients— especially those who are debilitated or have swallowing malfunction as a result of musculoskeletal disorders, stroke, or other factors. Interestingly, if the aspiration does not precipitate immediate symptoms, it might cause an inflammatory and granulomatous reaction responsible for symptoms later (even when the patient may have forgotten the aspiration). Both benign and malignant neoplasms of the larynx, vocal cord disorders (polyps, dysfunction, or paralysis), laryngocele, saccular cysts, laryngeal vascular lesions, and cervical and substernal goiters may obstruct the upper airways.1,2 In our patient, the diagnosis of subglottic stenosis could have been considered because the patient had undergone endotracheal intubation three times. On the basis of the information provided by the imaging studies, the differential diagnosis should include the following midline neck masses: dermoid cyst, sebaceous cyst, benign or malignant lymphadenopathy, lipoma, pyramidal lobe of thyroid, thyroid adenoma or carcinoma, goiter, aberrant thyroid tissue, salivary gland tumor, branchial cleft cyst, laryngocele, teratoma, and thyroglossal duct cyst.2 After performance of radiographic studies, we suspected the diagnosis of thyroglossal duct cyst in our patient. This presumptive diagnosis was confirmed by histologic examination of the surgical specimen. CONCLUSION Thyroglossal duct cyst occurs most commonly in children, but it can also manifest in adults, even in elderly persons. The cyst is always localized to the medial area of the neck, most often beside the lingual bone. In most patients, the first symptom of this condition is a painless lump in the neck; less
ANNALS OF ALLERGY, ASTHMA, & IMMUNOLOGY
frequently, the patient may have difficulty in swallowing and signs of infection (pain, redness, and swelling of the neck).3–5 We report a case of a thyroglossal duct cyst in an adult patient; it caused stridor and dyspnea as the initial symptoms. The thyroglossal duct cyst is the most common congenital neck mass, resulting from persistence and dilatation of remnants of an epithelial tract formed during migration of the thyroid during embryogenesis. Thyroglossal duct remnants are present in approximately 7% of the population. Although thyroglossal duct cysts generally manifest clinically in children, it is important to be aware that the lesion can occur in adults as well—sometimes late in life. Incidental carcinoma of the thyroglossal duct cyst is rare, but is more likely to occur in adults than in children.3–5 A thyroglossal duct cyst rarely induces dyspnea and stridor in adults. A MEDLINE search for articles on this subject published between 1966 and November 2001 disclosed only two reports (one in Japanese and the other in German).6,7 For the diagnosis of thyroglossal duct cyst, physical examination (inspection and palpation) of the neck and confirmation by thyroid ultrasonography and computed tomography of the neck are generally sufficient. Thyroid scintigraphy is primarily used preoperatively to demonstrate normal thyroid tissue. This procedure is believed to reduce the risk of postoperative hypothyroidism attributable to inadvertent removal of the only functioning thyroid tissue present within the thyroglossal duct cyst. Some physicians recommend thyroid scanning in all patients with thyroglossal duct cyst, whereas others advocate scintigraphy only when the cyst is present at the base of the tongue (because of the presence of ectopic thyroid tissue in 1 to 2% in such cases).3–5 For consideration of causes of dyspnea, pulmonary function tests (spirometry with flow-volume loops) are helpful and provide objective measurements of airflow obstruction. The configuration of the forced expiratory-inspiratory flowvolume loop can provide clues in the differential diagnosis of asthma and complicating conditions. In patients with variable extrathoracic airway obstruction, cutoff of the inspiratory peaks is evident. Improvement of spirometric findings during a period of a few minutes after inhalation of a -adrenergic bronchodilator reflects the component of bronchospasm in airway obstruction. Spirometry is appropriate for monitoring
VOLUME 90, MARCH, 2003
the course of disease and the response to therapy.8 In our patient, this technique provided useful information for the diagnosis and the postoperative followup. SUMMARY We describe an adult patient who had stridor and dyspnea as initial symptoms of a thyroglossal duct cyst. Spirometry and noninvasive imaging techniques have been useful for diagnosis of this condition. REFERENCES 1. O’Hollaren MT. Dyspnea originating from the larynx. Immunol Allergy Clin North Am 1996;16:69 –76. 2. Shepherd S, Geraci SA. The differential diagnosis of dyspnea: a pathophysiologic approach. Clin Rev 1999;9:52–54,59 – 61,65– 66,71–74. 3. Josephson GD, Spencer WR, Josephson JS. Thyroglossal duct cyst: the New York Eye and Ear Infirmary experience and a literature review. Ear Nose Throat J 1998;77:642– 644,646 – 647,651. 4. Ewing CA, Kornblut A, Greeley C, Manz H. Presentations of thyroglossal duct cysts in adults. Eur Arch Otorhinolaryngol 1999;256:136 –138. 5. Katz AD, Hachigian M. Thyroglossal duct cysts. A thirty year experience with emphasis on occurrence in older patients. Am J Surg 1988;155:741–744. 6. Honig M, Taake S, Hormann K. Mouth floor cyst with increasing dyspnea. Thyroglossal duct cyst in the area of the mouth floor [in German]. HNO 2000;48:398 –399. 7. Kobayashi M. A large thyroglossal duct cyst induced dyspnea in a 94-year-old patient. Otolaryngol Head Neck Surg 1996;68: 222–225. 8. Mathison DA. Asthma in adults: evaluation and management. In: Middleton E Jr, Reed CE, Ellis EF, et al, editors. Allergy: Principles and Practice. Vol 2. 5th ed. St Louis, MO: Mosby, 1998:904 –906. Requests for reprints should be addressed to: Dra. M. A´ngeles Gonzalo-Garijo Servicio de Alergologı´a Hospital Universitario Infanta Cristina Carretera de Portugal s/n 06080 Badajoz, Spain E-mail: [email protected]
297