History, Definition, and Epidemiology
History
- In 1948, Graham First Described the Middle Lobe Syndrome in 12 Patients with Atelectasis and Nontuberculous Pneumonitis of the Right Middle Lobe (Postgrad Med, 1948) [MEDLINE]
- These Cases Had Presumed (But Not Bronchoscopically–Proven) Airway Compression by Peribronchial Enlarged Lymph Nodes
- In 1955, Effler and Ervin Published a Review on the Anatomic and Clinical Features of the Middle Lobe Syndrome (Am Rev Tuberc, 1955) [MEDLINE]
- They Defined Middle Lobe Syndrome as a “Suppurative Process Which is Characterized by Recurrent Pneumonitis, Productive Cough, Recurrent Fever, and Frequent Hemoptyses”
- They Stated “The Middle Lobe Syndrome Begins with a Phase of Obstructive Pneumonitis and Terminates with a Phase in Which There is Destruction of the Lung Parenchyma Distal to the Point of Obstruction”
- In 1966, Culiner Described the Middle Lobe Syndrome as “Obstructive Atelectasis of This Lobe, with the Obstruction Being Attributed to Compression by Peribronchial Nodes” (Dis Chest, 1966) [MEDLINE]
Definition
- Middle Lobe Syndrome is Most Consistently Defined in the Medical Literature as Recurrent or Chronic Right Middle Lobe Atelectasis (Collapse or Volume Loss) (see Atelectasis) (Postgrad Med, 1948) [MEDLINE] (Dis Chest, 1966) [MEDLINE] (Thorax, 1980) [MEDLINE] (Respiration, 2012) [MEDLINE]
- A Similar Syndrome May Occur in the Lingula, Being Termed the “Lingula Syndrome” (Chest, 2004) [MEDLINE]
Epidemiology
- Middle Lobe Syndrome is Considered to Be a Rare Clinical Entity, But its Epidemiology Has Not Been Well-Described in the Medical Literature (Thorax, 1980) [MEDLINE] (Respiration, 2012) [MEDLINE]
- Middle Lobe Syndrome Has Been Described in Childen and Adults of Both Sexes
- Middle Lobe Syndrome Has Been Described in Both Primary and Tertiary Care Settings
- Non-Obstructive Middle Lobe Syndrome Appears to Be More Common than Obstructive Middle Lobe Syndrome (Clin Respir J, 2009) [MEDLINE]
- Incidence
- In a National Study from Iceland, the Incidence of Middle Lobe Syndrome Requiring Surgical Resection was Defined (JAMA, 1966) [MEDLINE]
- Male: 1.43 milion males per year
- Female: 2.94 milion females per year
- In a National Study from Iceland, the Incidence of Middle Lobe Syndrome Requiring Surgical Resection was Defined (JAMA, 1966) [MEDLINE]
- Sex-Predominance
- Middle Lobe Syndrome is More Common in Females
- The F:M Ratio is 1.5-3.0 in Most Studies (Respiration, 2012) [MEDLINE]
- Middle Lobe Syndrome is More Common in Females
- Family History of Atopy
- Familial Clustering
- Familial Clustering Has Been Reported
Etiology

Obstructive Middle Lobe Syndrome
Intrinsic Obstruction
- Infection
- Actinomycosis (see Actinomycosis)
- Echinococcosis (see Echinococcosis) (BMJ Case Rep, 2016) [MEDLINE]
- Mycobacterium Avium Complex (MAC) (see Mycobacterium Avium Complex)
- However, as Noted Below, Most Cases of Middle Lobe Syndrome Associated with Nontuberculous Mycobacteria Have a Patent Right Middle Lobe Bronchus (Dis Chest, 1966) [MEDLINE]
- Endobronchial Submucosal “Pearls” May Be Seen in HIV Patients (Biopsy of These is Usually Positive for Acid-Fast Bacilli)
- Mycobacterium Tuberculosis (Tuberculosis) (see Tuberculosis)
- Nocardiosis (see Nocardiosis)
- Neoplasm
- Epidemiology
- Neoplasms (Benign and Malignant) Account for Approximately 25% of Middle Lobe Syndrome Cases (Although Many Middle Lobe Syndrome Studies Have Excluded Patients with Identifiable Neoplasms) (Respiration, 2012) [MEDLINE]
- Types of Neoplasms
- Bronchial Adenoma (see Bronchial Adenoma)
- Hamartoma (see Hamartoma)
- Lung Cancer (see Lung Cancer)
- Endobronchial Metastases (see Lung Metastases-Endobronchial)
- Breast Cancer (see Breast Cancer): most common tumor to metastasize to airway
- Cervical Cancer (see Cervical Cancer)
- Chronic Lymphocytic Leukemia (CLL) (see Chronic Lymphocytic Leukemia)
- Colorectal Cancer (see Colorectal Cancer)
- Endometrioma (see Endometrioma)
- Esophageal Cancer (see Esophageal Cancer)
- Germ Cell Tumor (see Germ Cell Tumor)
- Head and Neck Cancer (see Head and Neck Cancer)
- Hepatocellular Carcinoma (see Hepatocellular Carcinoma)
- Hodgkin Lymphoma (see Hodgkin Lymphoma)
- Kaposi Sarcoma (see Kaposi Sarcoma)
- Lymphoma (see Lymphoma)
- Melanoma (see Melanoma)
- Ovarian Cancer (see Ovarian Cancer)
- Plasmacytoma (see Multiple Myeloma)
- Renal Cell Cancer (see Renal Cancer)
- Sarcoma
- Testicular Cancer (see Testicular Cancer)
- Thymic Carcinoma (see Thymoma)
- Thyroid Cancer (see Thyroid Cancer)
- Urothelial Cell Carcinoma (Transitional Cell Carcinoma) (see Urothelial Cell Carcinoma)
- Epidemiology
- Mucoid Impaction (see Mucoid Impaction)
- Allergic Bronchopulmonary Aspergillosis (ABPA) (see Allergic Bronchopulmonary Aspergillosis) (Eur Respir J, 1993) [MEDLINE]
- Asthma (see Asthma): predominantly seen in pediatric cases with history of asthma or atopy
- Bacillus Calmette-Guerin (BCG) (see Bacillus Calmette-Guerin)
- Cystic Fibrosis (CF) (see Cystic Fibrosis)
- Distal to Central Airway Obstruction (from Bronchial Atresia, Bronchial Carcinoid, Bronchogenic Cyst, etc)
- Lung Cancer (see Lung Cancer)
- Mycobacterium Avium Complex (MAC) (see Mycobacterium Avium Complex
- Sjogren’s Syndrome (see Sjogren’s Syndrome)
- Other Endobronchial Mass/Nodule/Anatomic Distortion
- Airway Foreign Body (see Airway Foreign Body): more commonly occurs in children
- Amyloidosis (see Amyloidosis): due to endobronchial amyloidosis
- Broncholithiasis (see Broncholithiasis): due to erosion of broncholith from adjacent lymph nodes into the right middle lobe bronchus
- Sarcoidosis (see Sarcoidosis): due to endobronchial granuloma
- Silicosis (see Silicosis): due to endobronchial silicosis
- Tracheobronchopathia Osteochondroplastica (TPO) (see Tracheobronchopathia Osteochondroplastica) (Adv Respir Med, 2017) [MEDLINE]: due to endobronchial nodules
Extrinsic Obstruction
- Peribronchial Lymphadenopathy
- Epidemiology
- Peribronchial Lymphadenopathy is the Most Common Etiology of Extrinsic Compression of the Right Middle Lobe Bronchus (Chest, 1966) [MEDLINE]
- Granulomatous Mediastinitis Disorders Which Cause Peribronchial Lymphadenopathy (see Granulomatous Mediastinitis and Fibrosing Mediastinitis)
- Blastomycosis (see Blastomycosis)
- Histoplasmosis (see Histoplasmosis): most common etiology in the US
- Mycobacterium Avium Complex (MAC) (see Mycobacterium Avium Complex)
- Mycobacterium Fortuitum (see Mycobacterium Fortuitum)
- Mycobacterium Tuberculosis (Tuberculosis) (see Tuberculosis): common cause in the US
- Sarcoidosis (see Sarcoidosis)
- Fibrosing Mediastinitis Disorders Which Cause Peribronchial Lymphadenopathy (see Granulomatous Mediastinitis and Fibrosing Mediastinitis)
- Blastomycosis (see Blastomycosis)
- Familial Multifocal Fibrosclerosis
- Histoplasmosis (see Histoplasmosis)
- Hodgkin Lymphoma (Nodular Sclerosing) (see Hodgkin Lymphoma)
- Methysergide (see Methysergide)
- Paraffin Plombage (Pneumonolysis): previously used to treat tuberculosis
- Radiation Therapy (see Radiation Therapy)
- Sarcoidosis (see Sarcoidosis)
- Silicosis (see Silicosis)
- Traumatic Mediastinal Hematoma
- Mycobacterium Tuberculosis (Tuberculosis) (see Tuberculosis)
- Other Disorders Which Cause Peribronchial Lymphadenopathy
- Asbestos (see Asbestos)
- Metastases to Peribronchial Lymph Nodes
- Epidemiology
- Other Extrinsic Etiology
- Cardiovascular Anomaly
- Esophageal Traction Diverticulum (see Esophageal Diverticulum) (Can Med Assoc J, 1981) [MEDLINE]
- Situs Inversus (see Situs Inversus)
Non-Obstructive Middle Lobe Syndrome (“Peripheral Middle Lobe Syndrome”)
General Comments
- Non-Obstructive Middle Lobe Syndrome is Characterized by Absence of Demonstrable Right Middle Lobe Bronchus Obstruction by Bronchoscopy
- Non-Obstructive Cases May Also Manifest Pathology in the Lingula on the Left Side (“Lingula Syndrome”) (Chest, 2004) [MEDLINE]
- Non-Obstructive Middle Lobe Syndrome Commonly Manifests as Recurrent Pneumonia in Association with Asthma, Bronchitis, or Cystic Fibrosis (JAMA, 1966) [MEDLINE] (J Maine Med Assoc, 1972) [MEDLINE] (Arch Dis Child, 1992) [MEDLINE]
Infection
- Actinomycosis (see Actinomycosis)
- Aspergillus (see Aspergillus)
- Blastomycosis (see Blastomycosis)
- Bordetella Pertussis (see Bordetella Pertussis)
- Chlamydophila Psittaci (Psittacosis) (see Psittacosis)
- Echinococcosis (see Echinococcosis)
- Haemophilus Influenza (see Haemophilus Influenza)
- Histoplasmosis (see Histoplasmosis)
- Moraxella Catarrhalis (see Moraxella Catarrhalis)
- Mycobacterium Avium Complex (MAC) (see Mycobacterium Avium Complex)
- Most Cases of Middle Lobe Syndrome Associated with Nontuberculous Mycobacteria Have a Patent Right Middle Lobe Bronchus (Dis Chest, 1966) [MEDLINE]
- In 1992, the “Lady Windermere Syndrome” was Described in a Series of Female Patients (n = 29) with MAC Infection Initially in Middle Lobe or Lingular Distributions (in the Absence of Airway Obstruction or Predisposing Pulmonary Disease) (Chest, 1992) [MEDLINE]
- Lady Windermere was a Fastidious Female Character in the Victorian-Era (1892) Oscar Wilde Play, “Lady Windermere’s Fan”
- The Authors Hypothesized that Voluntary Suppression of Cough May Have Led to the Development of Nonspecific Inflammation in the Poorly-Draining Middle Lobe or Lingula, Upon Which MAC Infection then Occurred
- Mycobacterium Fortuitum (see Mycobacterium Fortuitum)
- Most Cases of Middle Lobe Syndrome Associated with Nontuberculous Mycobacteria Have a Patent Right Middle Lobe Bronchus (Dis Chest, 1966) [MEDLINE]
- Mycobacterium Tuberculosis (Tuberculosis) (see Tuberculosis)
- Nocardiosis (see Nocardiosis)
- Staphylococcus Aureus (see Staphylococcus Aureus)
- Streptococcus Pneumoniae (Pneumococcus) (see Streptococcus Pneumoniae)
Other
- Asthma (see Asthma)
- Epidemiology
- Predominantly Seen in Pediatric Cases with History of Asthma or Atopy
- In a Series of Asthmatic Children with Middle Lobe Syndrome, Haemophilus Influenzae and Streptococcus Pneumoniae were the Predominant Organisms Recovered (see Haemophilus Influenzae and Streptococcus Pneumoniae) (Arch Dis Child, 1992) [MEDLINE]
- Epidemiology
- Bronchogenic Cyst (see Bronchogenic Cyst)
- Cystic Fibrosis (CF) (see Cystic Fibrosis)
- Idiopathic Middle Lobe Syndrome
- Physiology
- Unclear Pathogenesis
- Physiology
- Primary Ciliary Dyskinesia (see Primary Ciliary Dyskinesia)
- Pulmonary Infarction (see Pulmonary Infarction)
- Sjogren’s Syndrome (see Sjogren’s Syndrome)
- Physiology
- Lymphocytic Bronchiolitis in the Atelectatic Lobes (Med J Aust, 2006) [MEDLINE]
- Physiology
Physiology
Obstructive Middle Lobe Syndrome
Mechanisms
- Intrinsic Obstruction Due to Obstructing Endobronchial Lesion (Tumor, Mucous Plug, Mucoid Impaction, etc)
- Extrinsic Compression of the Middle Lobe Bronchus (by Peribronchial/Hilar Lymph Nodes Which Encircle the Right Middle Lobe Bronchus)
Therapy
- Surgery is the Typically the Preferred Therapy
Non-Obstructive Middle Lobe Syndrome (“Peripheral Middle Lobe Syndrome”)
Epidemiology
- Non-Obstructive Middle Lobe Syndrome (Characterized by an Absence of Airway Obstruction by Chest CT and/or Bronchoscopy) Accounts for the Majority of Middle Lobe Syndrome Cases (Respiration, 2012) [MEDLINE]
- Non-Obstructive Type May Also Occur in Other Lobes of the Lung, Most Commonly the Lingula
Possible Mechanisms (Respiration, 2012) [MEDLINE]
- Right Middle Lobe Bronchus Has a Narrow Diameter, Long Length, and an Acute Takeoff Angle, Creating Poor Conditions for Drainage (and Poor Clearance of Mucous)
- Right Middle Lobe Bronchus Typically Has a “Fish-Mouth” Configuration (as Does the Lingular Bronchus)
- Embryologic Factors
- Early in Embryologic Development, the Smaller Left Endodermal Bud is Directed More Laterally than the Caudally-Located Right Endodermal Bud, Resulting in Asymmetry of the Mainstem Bronchi
- Later in Embryologic Development, the Right Main Lung Bud Forms Three Lung Buds and the Left Lung Bud Forms Only Two Buds (Corresponding to the Later Pulmonary Lobes)
- Right Middle Has Relatively Poor Collateral Ventilation (as Compared to the Upper Lobes)
- Right Middle Lobe is Anatomically Surrounded by Two Fissures (with Scant Parenchymal Bridges), Which Impedes Collateral Ventilation (Similar Anatomic Features Occur in the Lingula)
- Poor Right Middle Lobe Collateral Ventilation (Especially in Patients with Complete Fissures) and Relative Anatomical Isolation Decrease the Probability of Reinflation Once Atelectasis Has Occurred (Radiology, 1983) [MEDLINE]
- Right Middle Lobe Has a Greater Ratio of Pleural Surface to Nonpleural Surface, as Compared to the Upper Lobes
- Collateral Ventilation in the Right Middle Lobe of Young Normal Subjects is Characterized by High Resistance and a Long-Time Constant, Relative to the Upper Lobes (Am Rev Respir Dis, 1978) [MEDLINE]
- Infection in the Right Middle Lobe
- Inflammation in the Right Middle Lobe
Therapy
- Medical Management is the Typically the Preferred Therapy
Association of Middle Lobe Syndrome with the Development of Bronchiectasis (see Bronchiectasis)
- Recurrent or Chronic Right Middle Lobe Syndrome May Result in Bronchiectasis
- Due to Recurrent and/or Chronic Infection/Inflammation
- Bronchiectasis Occurs in 50% of Cases (Respiration, 2012) [MEDLINE]
Diagnosis
Bronchoscopy (see Bronchoscopy)
- Required to Rule Out Endobronchial Pathology and Collect Specimens for Microbiologic Processing
- Bronchoscopy is Abnormal in Approximately 40% of Cases
- The Most Common Abnormalities Found are Right Middle Lobe Bronchial Stenosis or Endobronchial Tumor
- Endobronchial Ultrasound (EBUS) (seeEndobronchial Ultrasound)
- Useful to Detect Lymphadenopathy and Calcification
Chest X-Ray (CXR)/Chest Computed Tomography (Chest CT) (see Chest X-Ray and Chest Computed Tomography)
- Findings
- Normal: chest imaging may be normal in cases with intermittent or recurrent atelectasis
- Right Middle Lobe Infiltrate
- Right Middle Lobe Atelectasis
- On the Lateral Chest X-Ray: Anterior Wedge-Shaped Density with Base Toward Pleura and Apex Pointing Toward the Hilum
- Right Middle Lobe Bronchiectasis
Clinical
Pulmonary Manifestations
Chest Pain (see Chest Pain)
- Epidemiology
- May Occur (Clin Respir J, 2009) [MEDLINE]
Cough (see Cough)
- Epidemiology
- Clinical
- May Be Chronic or Recurrent
- May Be Productive
Dyspnea (see Dyspnea)
- Epidemiology
- May Occur (Clin Respir J, 2009) [MEDLINE]
Wheezing (see Wheezing)
- Epidemiology
- May Occur
- Clinical
- Wheezing May Be Localized in Cases with an Obstructive Etiology of the Middle Lobe Syndrome
Right Middle Lobe Atelectasis
- Diagnosis
- May Be Incidentally Noted on Chest X-Ray (CXR) or Chest Computed Tomography (CT) (see Chest X-Ray and Chest Computed Tomography)
- On the Posteroanterior Chest X-Ray, There is Obscuration of the Right Heart Border (Because the Medial Segment of the Right Middle Lobe is Adjacent to the Right Atrium)
- On the Lateral Chest X-Ray, There is Triangle of Increased Density Between the Minor Fissure and the Lower Half of the Major Fissure
- Chest CT Scan is Useful to Evaluate Bronchial Patency, Assess for Lymphadenopathy, Assess for Calcifications, and Detect Other Etiologies of Extrinsic Right Middle Lbe Airway Compression (Radiology, 1983) [MEDLINE]
- Bronchoscopy (see Bronchoscopy)
- Bronchoscopy is Critical to Evaluate for the Presence of Airway Abnormalities
- Bronchoscopic Sampling (Bronchoalveolar Lavage) is Useful to Collect Diagnostic Specimens
- Bacteria Studies: Gram stain, bacterial culture, etc
- Fungal Studies: fungal stain, fungal culture, etc
- Mycobacterial Studies: acid-fast bacterial (AFB) stain, mycobacterial culture, TB PCR, etc
- Cytologic Studies: to rule out malignancy
- Endobronchial Ultrasound (EBUS)
- Useful to Assess for Lymphadenopathy and Calcifications
- May Be Incidentally Noted on Chest X-Ray (CXR) or Chest Computed Tomography (CT) (see Chest X-Ray and Chest Computed Tomography)
- Clinical
- May Be Persistent or Intermittent
- Decreased Breath Sounds Over the Right Middle Lobe
Pneumonia
- Physiology
- Post-Obstructive Pneumonia (see Community-Acquired Pneumonia)
- In One Histopathologic Study of Right Middle Lobe Syndrome Cases Cured Surgically (n = 60), 60% Had Chronic Suppurative Infection, 33% Had Neoplasm, and 7% Had Tuberculosis (Med Interne, 1982) [MEDLINE]
- May Be Recurrent (Requiring Multiple Courses of Antibiotics, Bronchodilators, etc)
- Post-Obstructive Pneumonia (see Community-Acquired Pneumonia)
- Clinical
- Cough (see Cough)
- Fatigue (see Fatigue)
- Fever/Chills (see Fever)
- Hemoptysis (see Hemoptysis)
- Weight Loss (see Weight Loss)
- Vocal Fremitus (E->A Changes) Over the Right Middle Lobe: due to alveolar filling
Bronchiectasis (see Bronchiectasis)
- Epidemiology
- Bronchiectasis Occurs in 50% of Cases (Respiration, 2012) [MEDLINE]
- Physiology
- Due to Poor Secretion Clearance and Chronic/Recurrent Infection
Treatment
General Measures
Treatment of Underlying Asthma (If Present) (see Asthma)
- Bronchodilators: see below
- Inhaled Corticosteroids (see Corticosteroids)
- Other Standard Measures
Bronchodilators
- Short-Acting β2-Adrenergic Receptor Agonists (SABA’s) (see Β2-Adrenergic Receptor Agonists)
- Albuterol (Ventolin, Salbutamol, etc) (see Albuterol)
- Long-Acting/Ultra Long-Acting β2-Adrenergic Receptor Agonists (LABA’s) (see Β2-Adrenergic Receptor Agonists)
- Formoterol (Foradil, Oxeze, Oxis, Atock, Atimos, Perforomist) (see Formoterol)
- Olodaterol (Striverdi Respimat) (see Olodaterol)
- Salmeterol (Serevent) (see Salmeterol)
- Vilanterol (see Vilanterol)
- Short-Acting Muscarinic Receptor Antagonists (SAMA’s) (see Muscarinic Antagonists)
- Ipratropium Bromide (Atrovent) (see Ipratropium Bromide)
- Long-Acting Muscarinic Receptor Antagonists (LAMA’s) (see Muscarinic Antagonists)
- Tiotropium (Spiriva) (see Tiotropium)
Mechanical Secretion Clearance Modalities
- Not Well-Studied in the Treatment of Middle Lobe Syndrome (Chest, 2005) [MEDLINE]
- Modalities
- Chest Physical Therapy (CPT) (see Chest Physical Therapy)
- Flutter Valve (see Flutter Valve)
- High-Frequency Oscillation Respiratory Therapy (Vest) (see High-Frequency Oscillation Respiratory Therapy)
- Postural Drainage
- May Be Useful (Chest, 2005) [MEDLINE]
Mucolytics
- N-Acetylcysteine (Mucomyst) (see N-Acetylcysteine)
Antibiotics
- Empiric Antibiotic Coverage Against the Following Should Be Considered
- Haemophilus Influenzae (see Haemophilus Influenzae)
- Moraxella Catarrhalis (see Moraxella Catarrhalis)
- Streptococcus Pneumoniae (see Streptococcus Pneumoniae)
- Directed Antibiotic Coverage Against Specific Organisms Recovered from Bronchoscopy
- Mycobacteria
- Pseudomonas Aeruginosa (see Pseudomonas Aeruginosa): may be present in some difficult cases
- Low-Dose Roxithromycin (Macrolide) Therapy
- May Be Useful (Especially if Bronchiectasis is Present) (Respiration, 2001) [MEDLINE]
- Use of Nebulized Antibiotics Has Not Been Well Studied in Middle Lobe Syndrome
Bronchoscopy (see Bronchoscopy)
- Bronchoscopy May Be Useful to Enhance Secretion Clearance
- Intrabronchial Air Insufflation: to treat lobar collapse
- Balloon Dilation/Argon Plasma Coagulation/Electrocautery/Cryosurgery/Laser Therapy/Stent Placement: may be used in some cases
Surgical Resection (see Pulmonary Lobectomy)
- Right Middle Lobectomy May Be Required in Some Cases
- Cases with Obstructive Right Middle Lobe Syndrome are More Amenable to Surgical Intervention
- Indications for Right Middle Lobectomy
- Resistant/Complex Cases (Which are Unresponsive to Medical Therapy) and Who Have Proven Right Middle Lobe Bronchial Obstruction (Clin Respir J, 2009) [MEDLINE]
- Resistant/Complex Cases with Chronic Atelectasis (>6 Months) Despite Medical Therapy: especially if patient has associated debilitating symptoms (such as persistent cough, fever, failure to thrive, etc)
- Recurrent Hemoptysis, Not Amenable to Interventional Radiology Angioembolization (see Hemoptysis)
- Presence of Malignancy (or Concern for Underlying Malignancy) in Right Middle Lobe
- Surgical Approach
- Video-Assisted Thoracoscopic Approach is Feasible for the Surgical Management of Middle Lobe Syndrome in Selected Patients with No Severe Calcified Lymph Nodes Surrounding the Hilus Pulmonis (World J Surg, 2017) [MEDLINE]
References
- Middle lobe syndrome. Postgrad Med. 1948 Jul;4(1):29-34 [MEDLINE]
- The middle lobe syndrome; a review of the anatomic and clinical features. Am Rev Tuberc 1955;71:775–784 [MEDLINE]
- Middle-lobe syndrome. N Engl J Med. 253:489-495 1955 [MEDLINE]
- The right middle lobe syndrome, a non-obstructive complex. Dis Chest 1966;50:57–66 [MEDLINE]
- Chronic middle lobe infection. Factors responsible for its development. Ann Thorac Surg 1966;2:612–616 [MEDLINE]
- Right middle lobe syndrome in children. JAMA 1966;197:8–14 [MEDLINE]
- Middle lobe disease. South Med J 1967;60:1029–1032 [MEDLINE]
- Middle lobe syndrome in asthmatic children. J Maine Med Assoc 1972;63:46–48 [MEDLINE]
- Collateral ventilation and the middle lobe syndrome. Am Rev Respir Dis 1978;118: 305–310 [MEDLINE]
- Isolated middle lobe atelectasis: aetiology, pathogenesis, and treatment of the so-called middle lobe syndrome. Thorax 1980;35:449–452 [MEDLINE]
- Traction diverticula of the esophagus in the middle lobe syndrome. Can Med Assoc J 124:1320-1322, 1981 [MEDLINE]
- Pathology of the middle lobe syndromes. A histopathological and pathogenetic analysis of sixty surgically-cured cases. Med Interne 1982;20: 73–8 [MEDLINE]
- Middle lobe syndrome: diagnosis and management. Ann Thorac Surg 1982;33:28–31 [MEDLINE]
- Middle lobe syndrome. Ann Thorac Surg 1983;35:679–686 [MEDLINE]
- Peripheral middle lobe syndrome. Radiology 1983;149:17–21 [MEDLINE]
- Right middle lobe syndrome in children. Int J Pediatr Otorhinolaryngol 1987;13:11–23 [MEDLINE]
- Infection with Mycobacterium avium complex in patients without predisposing conditions. N Engl J Med. 1989 Sep 28;321(13):863-8 [MEDLINE]
- Mycobacterium avium complex pulmonary disease presenting as an isolated lingular or middle lobe pattern. The Lady Windermere syndrome. Chest. 1992 Jun;101(6):1605-9 [MEDLINE]
- Right middle lobe syndrome caused by Mycobacterium fortuitum in a patient with human immunodeficiency virus infection. South Med J 1992; 85:767–769 [MEDLINE]
- Role of infection in the middle lobe syndrome in asthma. Arch Dis Child 1992;67:592–594 [MEDLINE]
- Allergic bronchopulmonary aspergillosis with middle lobe syndrome and allergic Aspergillus sinusitis. Eur Respir J. 1993 Jun;6(6):917-8 [MEDLINE]
- Middle lobe syndrome: a clinicopathological study of 21 patients. Hum Pathol 1995;26: 302–307 [MEDLINE]
- Outcome after right middle lobe syndrome. Chest 1995;108:150–15 [MEDLINE]
- Case report: Blastomyces dermatitidis as a cause of middle lobe syndrome. Am J Med Sci 1996; 312:191–193 [MEDLINE]
- Middle lobe syndrome. Am Fam Physician 1996;53:2547– 2550 [MEDLINE]
- The right middle-lobe syndrome–a case report and review of the literature. S Afr Med J. 1997 Feb;87(2):178-9 [MEDLINE]
- Right middle lobe atelectasis associated with endobronchial silicotic lesions. Arch Pathol Lab Med 2000;124:1619–1622 [MEDLINE]
- Improvement in right lung atelectasis (middle lobe syndrome) following administration of low-dose roxithromycin. Respiration 2001;68: 210–214 [MEDLINE]
- Sarcoidosis with multiple organ involvement emerging as Lofgren’s syndrome. Intern Med 2003;42: 534–537 [MEDLINE]
- Resection of the right middle lobe and lingula in children for middle lobe/lingula syndrome. Chest 2004;125:38–42 [MEDLINE]
- Congenital anomalies of the tracheobronchial tree, lung, and mediastinum: embryology, radiology, and pathology. Radiographics 2004;24:e17 [MEDLINE]
- Middle lobe syndrome in children with asthma: review of 56 cases. J Asthma 2004;41:411–417 [MEDLINE]
- The role of timely intervention in middle lobe syndrome in children. Chest 2005;128: 2504–2510 [MEDLINE]
- A case of Mycobacterium avium complex pulmonary disease in an immunocompetent host. South Med J. 2005;98(10):1036-1038 [MEDLINE]
- Middle lobe syndrome as the pulmonary manifestation of primary Sjogren’s syndrome. Med J Aust 2006;184:294–295 [MEDLINE]
- Bronchial hyperresponsiveness, atopy, and bronchoalveolar lavage eosinophils in persistent middle lobe syndrome. Pediatr Pulmonol 2006;41:805–811 [MEDLINE]
- Bronchial anthracofibrosis and tuberculosis presenting as a middle lobe syndrome. Prim Care Respir J 2008;17:51–55 [MEDLINE]
- Endobronchial tuberculosis presenting as right middle lobe syndrome: clinical characteristics and bronchoscopic findings in 22 cases. Yonsei Med J 2008;49:615–619 [MEDLINE]
- Bronchiectasis. Radiol Clin North Am 2009;47:289–306 [MEDLINE]
- Chyloptysis with right middle lobe syndrome complicated postoperatively by chylothorax: an unusual cause of right middle lobe syndrome. Can Respir J 2009;16:e1–e2 [MEDLINE]
- Middle lobe syndrome: a nationwide study on clinicopathological features and surgical treatment. Clin Respir J 2009;3:77–81 [MEDLINE]
- Thoracoscopic lobectomy as a treatment option for persistent middle lobe syndrome in children. J Pediatr Int 2010;52:79–81 [MEDLINE]
- Middle lobe syndrome: a review of clinicopathological features, diagnosis and treatment. Respiration. 2012;84(1):80-6 [MEDLINE]
- Middle lobe syndrome in children today. Pediatr Respir Rev 2014 Jun;15(2):188-93. doi: 10.1016/j.prrv.2014.01.002 [MEDLINE]
- Ten years’ experience in surgical treatment of right middle lobe syndrome. Ann Thorac Cardiovasc Surg. 2015;21(4):354-8. doi: 10.5761/atcs.oa.14-00273 [MEDLINE]
- Middle lobe syndrome: a singularly rare presentation of complicated pulmonary hydatid disease. BMJ Case Rep. 2016 Apr 4;2016. pii: bcr2016214670. doi: 10.1136/bcr-2016-214670 [MEDLINE]
- Endobronchial Silicosis and Tuberculosis Presenting as the Right Middle Lobe Syndrome. J Bronchology Interv Pulmonol. 2016 Oct;23(4):e35-e37 [MEDLINE]
- Middle lobe syndrome: An exceptional presentation of concomitant lepidic adenocarcinoma and bronchial anthracofibrosis. Monaldi Arch Chest Dis. 2017 Dec 19;87(3):864. doi: 10.4081/monaldi.2017.864 [MEDLINE]
- Tracheobronchopathia osteochondroplastica – a 61-year-old female with middle lobe syndrome Adv Respir Med. 2017;85(3):158-160. doi: 10.5603/ARM.2017.0027 [MEDLINE]
- Middle lobe syndrome: an intriguing presentation of tracheobronchial amyloidosis. BMJ Case Rep. 2017 May 22;2017. pii: bcr-2017-219480. doi: 10.1136/bcr-2017-219480 [MEDLINE]
- A Comparative Study of Video-Assisted Thoracic Surgery with Thoracotomy for Middle Lobe Syndrome. World J Surg. 2017 Mar;41(3):780-784. doi: 10.1007/s00268-016-3777-6 [MEDLINE]
- Infectious Causes of Right Middle Lobe Syndrome. Cancer Control. 2017 Jan;24(1):60-65 [MEDLINE]
- Image Diagnosis: Endobronchial Tuberculosis Masquerading as an Endobronchial Tumor with Presentation as Middle Lobe Syndrome. Perm J. 2017;21. pii: 16-006. doi: 10.7812/TPP/16-006 [MEDLINE]
- A Comparative Study of Video-Assisted Thoracic Surgery with Thoracotomy for Middle Lobe Syndrome. World J Surg. 2017 Mar;41(3):780-784. doi: 10.1007/s00268-016-3777-6 [MEDLINE]
- Middle lobe syndrome: An exceptional presentation of concomitant lepidic adenocarcinoma and bronchial anthracofibrosis. Monaldi Arch Chest Dis. 2017 Dec 19;87(3):864. doi: 10.4081/monaldi.2017.864 [MEDLINE]
- Non-Obstructive Middle Lobe Syndrome: An Unusual Cause of Recurrent Pneumonia in an Elderly Woman. Eur J Case Rep Intern Med. 2018 Jan 31;5(1):000737. doi: 10.12890/2017_000737. eCollection 2018 [MEDLINE]