Right Middle Lobe Syndrome Clinical Presentation
- Author: Nemr S Eid, MD, FAAP, FCCP; Chief Editor: Michael R Bye, MD more...
History
The most common symptoms in right middle lobe syndrome (RMLS) include the following:
- Persistent or recurrent cough
- Intermittent wheezing
- Dyspnea
- History of recurrent or chronic pneumonia (May often be a misinterpretation of the radiographic findings)
In many cases, these respiratory symptoms are refractory to normal treatment.
At least half of the patients report a history of asthma or atopy, and one third report a family history of atopy.
Less frequently reported symptoms, which may be indicative of chronic disease with suppurative complications, include the following:
- Hemoptysis
- Low-grade fever
- Fatigue
- Weight loss
- Chest pain
Physical
- Right middle lobe syndrome is essentially a radiographic diagnosis, and physical findings widely vary.
- Auscultation of the lungs may reveal a fine wheeze, rales, or diffuse rhonchi, ranging from decreased aeration and dullness to percussion in the region of the right middle lobe. The right middle lobe is anterior, best heard at the nipple. The medial segment is located medial to the nipple; the lateral segment is lateral to the nipple. Failure to listen to this area results in failure to hear the right middle lobe.
- Clubbing is rarely found in patients with advanced disease.
Causes
Intra-airway origin
In children, right middle lobe syndrome is usually secondary to primary ventilation disorders. Chronic inflammation of the airways, which contributes to atelectasis of the right middle lobe, is present. A paucity of collateral ventilation is observed in children and serves to prevent reinflation.
Primary disorders of ventilation include the following:
- Asthma
- Chronic pneumonia or bronchitis
- Other chronic lung diseases caused by aspiration or gastroesophageal reflux
- Primary ciliary dyskinesia (immotile cilia syndrome
Airway foreign body aspiration include the following:
- Endobronchial tumors
- Mucous plugging, as from any of the above
- Granulation tissue
Extra-airway origin
Extraluminal compression is caused by the following:
- Cardiovascular anomalies
- Congenital malformations such as situs inversus and other anatomical defects such as anomalous branching or abnormal diameter, length, or structure of the bronchi
- Lymphadenopathy of peribronchial nodes
- Tumors
- Traction diverticula of the esophagus
Infectious etiologies
- Whether the infection is a cause of the collapse or a result of airway stasis and poor clearance may not be clear.
- Primary infectious etiology is more frequent in adults; however, one pediatric study found that 50% of children with collapsed right middle lobe had an underlying bacterial infection.[1]
- Infectious causes also increase in frequency among immunocompromised patients.
- Common bacterial causes in children include Streptococcus pneumoniae and Haemophilus influenzae.
- Fungal causes include histoplasmosis, blastomycosis, and aspergillosis, which manifest as allergic bronchopulmonary aspergillosis (APBA).
- Mycobacteria, including Mycobacterium tuberculosis, Mycobacterium avium-intracellulare, and Mycobacterium fortuitum have also been identified as causal agents.
- Occurrence is mainly caused by extrinsic compression by hilar lymph nodes, which are commonly observed in these infections as well as in fungal infections.
Springer C, Avital A, Noviski N, et al. Role of infection in the middle lobe syndrome in asthma. Arch Dis Child. May 1992;67(5):592-4. [Medline].
[Guideline] Institute for Clinical Systems Improvement (ICSI). Diagnosis and management of asthma. Jan 2008;[Full Text].
Priftis KN, Mermiri D, Papadopoulou A, et al. The role of timely intervention in middle lobe syndrome in children. Chest. Oct 2005;128(4):2504-10. [Medline].
[Best Evidence] Halliday HL, Ehrenkranz RA, Doyle LW. Early (< 8 days) postnatal corticosteroids for preventing chronic lung disease in preterm infants. Cochrane Database Syst Rev. Jan 21 2009;CD001146. [Medline].
American Journal of Medicine. Right middle lobe syndrome progressing to death in a 77-year-old woman. Am J Med. Mar 1987;82(3):471-80. [Medline].
Ayed AK. Resection of the right middle lobe and lingula in children for middle lobe/lingula syndrome. Chest. Jan 2004;125(1):38-42. [Medline]. [Full Text].
Brown M, Lemen R. Bronchiectasis. In: Kendig's Disorders of the Respiratory Tract in Children. Philadelphia, Pa: WB Saunders Co; 1998:150-2.
Case records of the Massachusetts General Hospital. Weekly clinicopathological exercises. Case 19-1984. A 57-year-old woman with recurrent pneumonia. N Engl J Med. May 10 1984;310(19):1245-52. [Medline].
De Boeck K, Willems T, Van Gysel D, et al. Outcome after right middle lobe syndrome. Chest. Jul 1995;108(1):150-2. [Medline]. [Full Text].
Dees SC, Spock A. Right middle lobe syndrome in children. JAMA. Jul 4 1966;197(1):8-14. [Medline].
Eggleston PA, Ward BH, Pierson WE, Bierman CW. Radiographic abnormalities in acute asthma in children. Pediatrics. Oct 1974;54(4):442-9. [Medline].
Gudmundsson G, Gross TJ. Middle lobe syndrome. Am Fam Physician. Jun 1996;53(8):2547-50. [Medline].
Kinzy JD, Powers WP, Baddour LM. Case report: Blastomyces dermatitidis as a cause of middle lobe syndrome. Am J Med Sci. Oct 1996;312(4):191-3. [Medline].
Kwon KY, Myers JL, Swensen SJ, Colby TV. Middle lobe syndrome: a clinicopathological study of 21 patients. Hum Pathol. Mar 1995;26(3):302-7. [Medline].
Lambert GW, Baddour LM. Right middle lobe syndrome caused by Mycobacterium fortuitum in a patient with human immunodeficiency virus infection. South Med J. Jul 1992;85(7):767-9. [Medline].
Livingston GL, Holinger LD, Luck SR. Right middle lobe syndrome in children. Int J Pediatr Otorhinolaryngol. Jun 1987;13(1):11-23. [Medline].
Priftis KN, Anthracopoulos MB, Mermiri D, et al. Bronchial hyperresponsiveness, atopy, and bronchoalveolar lavage eosinophils in persistent middle lobe syndrome. Pediatr Pulmonol. Sep 2006;41(9):805-11. [Medline].
Rock MJ. The diagnostic utility of bronchoalveolar lavage in immunocompetent children with unexplained infiltrates on chest radiograph. Pediatrics. Mar 1995;95(3):373-7. [Medline].
Saha SP, Mayo P, Long GA, McElvein RB. Middle lobe syndrome: diagnosis and management. Ann Thorac Surg. Jan 1982;33(1):28-31. [Medline].
Shah A, Bhagat R, Panchal N, et al. Allergic bronchopulmonary aspergillosis with middle lobe syndrome and allergic Aspergillus sinusitis. Eur Respir J. Jun 1993;6(6):917-8. [Medline].
Thacher H, Kaplan A. Middle lobe syndrome in asthmatic children. J Maine Med Assoc. Mar 1972;63(3):46-8 passim. [Medline].
Torkian B, Kanthan R, Burbridge B. Diagnostic pitfalls in fine needle aspiration of solitary pulmonary nodules: two cases with radio-cyto-histological correlation. BMC Pulm Med. Sep 8 2003;3(1):2. [Medline]. [Full Text].
Wagner RB, Johnston MR. Middle lobe syndrome. Ann Thorac Surg. Jun 1983;35(6):679-86. [Medline].

