Middle lobe syndrome: Twenty years' surgical experience

Introduction: Middle lobe syndrome (MLS) is defined as recurrent or chronic collapse of the middle lobe. This study evaluates clinico-radiological features and surgical management of MLS. Methods: Clinical data of 157 patients with obstructive MLS or non-obstructive MLS were collected from the patients’ records between 2000 and 2020 in our Thoracic surgery departement in Abderrahmen Mami hospital, Tunisia. Results: We studied 91 females (58%) and 66 males(42%) with a mean age of 33,18 +/- 19,85. The most common clinical features were chronic cough with productive sputum(90%), recurrent infection(55%) and intermittent hemoptysis(50%). Bronchoscopy was performed for all patients showing an endobronchial lesion in 7,64% of cases, an extrinsic compression in 5 %, an avascular white membranous structure in 3% and no evidence of a central obstructive lesion for the other patients. Middle lobe collapse was seen in chest computed tomography in all cases. Bronchiectasis was the most common etiological factor in these series (53,5%). Hydatic cyst was not rare and was final pathology in 28% of patients. Ten patients (6,36%) had intraluminal carcinoid in middle lobe bronchus. Minor findings included tuberculosis (5%), broncholithiasis (3%) and peribronchial inflammation. All patients underwent middle lobe resection. They survived surgery with minor peri- and postoperative complications. Conclusion: MLS can be treated effectively with middle lobe resection, with low mortality rate and favorable outcome. Bronchiectasis is the most common histological finding. Hydatid cyst isn’t a rare cause of MLS due to its high prevalence in north africa countries.