Tuberc Respir Dis.  2007 Mar;62(3):192-196. 10.4046/trd.2007.62.3.192.

Causes of Right Middle Lobe Syndrome: Recent Experience in Local Tertiary Hospital for Several Years

• Kim HO
• Ma JE
• Lee SJ
• Cho YJ
• Jeong YY
• Jeon KN
• Kim HC
• Lee JD
• Hwang YS

• KMID: 1518463
• DOI: http://doi.org/10.4046/trd.2007.62.3.192

Abstract

BACKGROUND: Right middle lobe syndrome (RMLS) is defined as transient or chronic and recurrent atelectasis of the right middle lobe. Although numerous conditions are associated with RMLS, there are very few recent reports in Korea. This study evaluated the causes of RMLS in a local tertiary hospitalover a period of 42 months. METHOD: Eighty-eight patients (M:F=64:22, mean age: 67.2+/-10.3 years), who had consistent chest radiography findings and underwent bronchoscopy in Gyeongsang University Hospital from January 2003 to July 2006, were enrolled in this study. The clinical characteristics and causes of RMLS in these patients were retrospectively reviewed.
RESULTS
The most common symptoms fo RMLS were cough, dyspnea and sputum. Tuberculosis was the most common cause (endobronchial tuberculosis in 22 and pulmonary tuberculosis in 1) The other causes were bronchial stenosis by benign fibrotic changes in 22 cases (25%), anthracofibrosis in 13 cases (14.8%), pneumonia in 11 cases (12.5%), lung cancer in 10 cases (11.4%), mucus impaction in 3 cases (3.4%), bronchiectasis in 2 cases (2.3%) and no demonstrable causes in 7 cases (8%). The bronchoscopy findings were mucosal edema with hyperemic changes in 38 cases (43.2%), mucosal edema with anthracotic pigmentation in 16 cases (18.2%), mucus impaction in 13 cases (14.8%), fibrotic stenosis in 13 cases (14.8%), a mass like lesion in 8 cases (9.1%), exudative necrotic material in 4 cases (4.5%), narrowing as a result of extrinsic compression in 2 cases (2.3%) and no demonstrable abnormalities in 12 cases (13.6%).
CONCLUSION
Right middle lobe syndrome was observed more frequently in patients over the age of 65. The causes were mainly benign diseases with endobronchial tuberculosis being the most common.

Keyword

Right middle lobe syndrome; Causes

MeSH Terms

Bronchiectasis
Bronchoscopy
Constriction, Pathologic
Cough
Dyspnea
Edema
Humans
Korea
Lung Neoplasms
Middle Lobe Syndrome*
Mucus
Pigmentation
Pneumonia
Pulmonary Atelectasis
Radiography
Retrospective Studies
Sputum
Tertiary Care Centers*
Thorax
Tuberculosis
Tuberculosis, Pulmonary

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