Middle lobe syndrome: a nationwide study on clinicopathological features and surgical treatment

Granulomatous Lung Diseases: A Practical Approach and Review of Common Entities

Granulomas are frequently encountered by pathologists in all types of lung specimens and arise from diverse etiologies. They should always be reported as necrotizing or non-necrotizing, with microorganism stains performed to evaluate for infection. With attention to distribution, quality (poorly vs well-formed), associated features, and correlation with clinical, radiologic, and laboratory data, the differential diagnosis for granulomatous lung disease can usually be narrowed to a clinically helpful "short list." This review describes a practical approach to pulmonary granulomas and reviews the clinicopathological aspects of common entities, including infectious (mycobacteria, fungi) and noninfectious (hypersensitivity pneumonitis, sarcoid, and vasculitis) causes.

Unveiling the complexity of right middle lobe syndrome: a case series highlighting the association with asthma

Introduction and importance

Right middle lobe syndrome (MLS) is a rare lung disorder primarily affecting children with a history of asthma or atopy. It encompasses a range of pathological and clinical conditions, from recurrent collapses of the middle lobe to bronchiectasis. In this study, the authors present a case series featuring four individuals with MLS associated with asthma, aiming to deepen our understanding of this uncommon condition.

Case presentation

Four paediatric patients with right MLS exhibited symptoms of persistent cough, dyspnoea, and recurrent asthma exacerbations. Radiographic evaluations confirmed features consistent with right MLS, and bronchoscopy revealed mucus plugs and oedematous airways obstructing the right middle lobe bronchus. Treatment with bronchodilators, antibiotics, and corticosteroids led to symptom improvement and resolution of atelectasis.

Clinical discussion

MLS is a rare condition characterized by chronic collapse of the right middle lobe and bronchiectasis. It is challenging to diagnose MLS, but computed tomography (CT) scans provide detailed lung images for confirmation. Treatment focuses on addressing the underlying cause, such as infections or mucus obstruction. Lobectomy may be considered in severe cases. This case series emphasizes the need for further research on MLS, as its rarity and characteristics remain unclear.

Conclusion

These cases exhibited obstructive MLS with and without asthma. Accurate diagnosis is challenging, requiring imaging techniques. MLS has clinical implications, particularly in asthma patients. Future studies should focus on understanding the aetiology of non-obstructive MLS.

Case Report: Middle lobe syndrome: a rare presentation in eosinophilic granulomatosis with polyangiitis

Background

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of disorders characterized by necrotizing inflammation of small- and medium-sized blood vessels and the presence of circulating ANCA. Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic ANCA-associated vasculitis, characterized by peripheral eosinophilia, neuropathy, palpable purpuras or petechiae, renal and cardiac involvement, sinusitis, asthma, and transient pulmonary infiltrates. Middle lobe syndrome (MLS) is defined as recurrent or chronic atelectasis of the right middle lobe of the lung, and it is a potential complication of asthma.

Case presentation

Herein, we describe a case of MLS in a 51-year-old woman, never-smoker, affected by EGPA, presenting exclusively with leukocytosis and elevated concentrations of acute-phase proteins, without any respiratory symptom, cough, or hemoptysis. Chest computed tomography (CT) imaging documented complete atelectasis of the middle lobe, together with complete obstruction of lobar bronchial branch origin. Fiberoptic bronchoscopy (FOB) revealed complete stenosis of the middle lobar bronchus origin, thus confirming the diagnosis of MLS, along with distal left main bronchus stenosis. Bronchoalveolar lavage (BAL) did not detect any infection. Bronchial biopsies included plasma cells, neutrophil infiltrates, only isolated eosinophils, and no granulomas, providing the hypothesis of vasculitic acute involvement less likely. First-line agents directed towards optimizing pulmonary function (mucolytics, bronchodilators, and antibiotic course) were therefore employed. However, the patient did not respond to conservative treatment; hence, endoscopic management of airway obstruction was performed, with chest CT documenting resolution of middle lobe atelectasis.

Conclusion

To the best of our knowledge, this is the first detailed description of MLS in EGPA completely resolved through FOB. Identification of MLS in EGPA appears essential as prognosis, longitudinal management, and treatment options may differ from other pulmonary involvement in AAV patients.

Asthma with recurrent middle lobe syndrome in children: Clinical features and lung function patterns

BACKGROUND

Middle lobe syndrome (MLS) is a complication of childhood asthma. This study aimed to compare the clinical features and lung function between asthmatic children with recurrent MLS and transient right middle lobe (RML) and/or lingula atelectasis.

METHODS

This study retrospectively analyzed asthmatic children with RML and/or lingula atelectasis between 2010 and 2020 using data from the pediatric pulmonary department. According to the episodes of atelectasis, children were divided into recurrent (≥2 episodes) and non-recurrent (only 1 episode) MLS groups, to compare clinical features and lung function. Spirometry during acute asthma exacerbation and stable stages were recorded, and variations were calculated.

RESULTS

A total of 35 children with asthma and RML and/or lingula atelectasis were included, 15 of whom had recurrent MLS. The recurrent MLS group had a higher proportion of girls, infections, family allergy history, severe asthma, severe exacerbation, and higher levels of total IgE than the non-recurrent MLS group (P < 0.05). The recurrent MLS group had a significantly higher % predicted and z-scores for forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC), a greater proportion of high FEV₁ and higher variations in FEV₁ and FVC than that in the non-recurrent group (P < 0.05). After excluding children with mild to moderate asthma in the recurrent MLS group, the differences in clinical features disappeared, but the results regarding lung function remained similar, when compared to severe asthma patients without RML and/or lingula atelectasis.

CONCLUSIONS

Childhood asthma with recurrent MLS has more frequent severe asthma and exacerbation but high lung function and variations.

Prevalence and course of disease after lung resection in primary ciliary dyskinesia: a cohort & nested case-control study

Background

Lung resection is a controversial and understudied therapeutic modality in Primary Ciliary Dyskinesia (PCD). We assessed the prevalence of lung resection in PCD across countries and compared disease course in lobectomised and non-lobectomised patients.

Methods

In the international iPCD cohort, we identified lobectomised and non-lobectomised age and sex-matched PCD patients and compared their characteristics, lung function and BMI cross-sectionally and longitudinally.

Results

Among 2896 patients in the iPCD cohort, 163 from 20 centers (15 countries) underwent lung resection (5.6%). Among adult patients, prevalence of lung resection was 8.9%, demonstrating wide variation among countries. Compared to the rest of the iPCD cohort, lobectomised patients were more often females, older at diagnosis, and more often had situs solitus. In about half of the cases (45.6%) lung resection was performed before presentation to specialized PCD centers for diagnostic work-up. Compared to controls (n = 197), lobectomised patients had lower FVC z-scores (− 2.41 vs − 1.35, p = 0.0001) and FEV1 z-scores (− 2.79 vs − 1.99, p = 0.003) at their first post-lung resection assessment. After surgery, lung function continued to decline at a faster rate in lobectomised patients compared to controls (FVC z-score slope: − 0.037/year Vs − 0.009/year, p = 0.047 and FEV1 z-score slope: − 0.052/year Vs − 0.033/year, p = 0.235), although difference did not reach statistical significance for FEV1. Within cases, females and patients with multiple lobe resections had lower lung function.

Conclusions

Prevalence of lung resection in PCD varies widely between countries, is often performed before PCD diagnosis and overall is more frequent in patients with delayed diagnosis. After lung resection, compared to controls most lobectomised patients have poorer and continuing decline of lung function despite lung resection. Further studies benefiting from prospective data collection are needed to confirm these findings.

The Saudi Thoracic Society guidelines for diagnosis and management of noncystic fibrosis bronchiectasis

This is the first guideline developed by the Saudi Thoracic Society for the diagnosis and management of noncystic fibrosis bronchiectasis. Local experts including pulmonologists, infectious disease specialists, thoracic surgeons, respiratory therapists, and others from adult and pediatric departments provided the best practice evidence recommendations based on the available international and local literature. The main objective of this guideline is to utilize the current published evidence to develop recommendations about management of bronchiectasis suitable to our local health-care system and available resources. We aim to provide clinicians with tools to standardize the diagnosis and management of bronchiectasis. This guideline targets primary care physicians, family medicine practitioners, practicing internists and respiratory physicians, and all other health-care providers involved in the care of the patients with bronchiectasis.

Infectious Causes of Right Middle Lobe Syndrome

Right middle lobe (RML) syndrome is defined as recurrent or chronic obstruction or infection of the middle lobe of the right lung. Nonobstructive causes of middle lobe syndrome include inflammatory processes and defects in the bronchial anatomy and collateral ventilation. We report on 2 case patients with RML syndrome, one due to infection with Mycobacterium avium complex followed by M asiaticum infection and the other due to allergic bronchopulmonary aspergillosis. A history of atopy, asthma, or chronic obstructive pulmonary disease has been reported in up to one-half of those with RML. The diagnosis can be made by plain radiography, computed tomography, and bronchoscopy. Medical treatment consists of bronchodilators, mucolytics, and antimicrobials. Patients whose disease is unresponsive to treatment and those with obstructive RML syndrome can be offered surgical treatment.

A Comparative Study of Video-Assisted Thoracic Surgery with Thoracotomy for Middle Lobe Syndrome

OBJECTIVES

The aim of this study is to evaluate the feasibility and safety of video-assisted thoracic surgery (VATS) for the treatment of middle lobe syndrome (MLS) through comparison with thoracotomy during the same period.

METHODS

We retrospectively reviewed all consecutive patients with MLS who underwent lobectomy or lingular segmentectomy between December 2005 and November 2015 in a single institute. Thirty patients were enrolled and divided into two groups: VATS group (n = 19) and thoracotomy group (n = 11). Data regarding the patients' demographics, medical history were collected and statistically compared.

RESULTS

All patients received successful middle lobe resection or lingular segmentectomy. In terms of operation time, blood transfusion, chest drainage amount, duration of chest drainage and postoperative complications, no significant differences were found between the two groups (p > 0.05). The mean intraoperative blood loss of VATS group was less than thoracotomy group (79.0 ± 63.9 vs. 165 ± 94.9 ml, p = 0.04). In VATS group, the mean length of postoperative hospital stay was 6.0 ± 2.4 days, shorter than that in group thoracotomy (9.0 ± 3.5 days, p = 0.01).

CONCLUSIONS

VATS was a feasible and safe method for the surgical treatment of MLS in selected patients when no severe calcified lymph nodes surrounding hilus pulmonis was observed by preoperative chest CT scan.

Right middle lobe atelectasis in children with asthma and prognostic factors

BACKGROUND

Although right middle lobe (RML)-atelectasis of the lungs is a common complication of asthma, the relevant data is limited. The aim of this study is to define the characteristics of RML atelectasis in asthma during childhood.

METHODS

Children with asthma who had recently developed RML atelectasis were included; anti-inflammatory medications, clarithromycin, and inhaled salbutamol were prescribed, chest-physiotherapy (starting on the sixth day) was applied. Patients were reevaluated on the sixth, fourteenth, thirtieth, and ninetieth days, chest X-rays were taken if the atelectasis had not resolved at the time of the previous visit.

RESULTS

Twenty-seven patients (6.8 (4.8-8.3) years, 48.1% male) with RML atelectasis were included. Symptoms started 15 (7-30) days before admission. The thickness of the atelectasis was 11.8 ± 5.8 mm; FEV1% was 75.9 ± 14.2 and Childhood Asthma Control Test scores were 11.8 ± 5.6 at the time of admission. The atelectasis had been resolved by the sixth (n = 3), fourteenth (n = 9), thirtieth (n = 10), and ninetieth days (n = 3). The treatment response of the patients whose atelectasis resolved in fourteen days was better on the sixth-day (atelectasis thickness: 4.7 ± 1.7 vs. 11.9 ± 7.3 mm, p = 0.021) compared to those whose atelectasis resolved later. Nearly half (54.5%) of the patients whose atelectasis had resolved by fourteen days were using controller medications at the time of admission. However, only two patients (13.3%) were on controller treatment in the latter group (p = 0.032). Regression analysis didn't reveal any prognostic factors for the early resolution of atelectasis.

CONCLUSIONS

Early diagnosis and treatment of RML atelectasis prevents complications. Patients who had early resolution of atelectasis had already been on anti-inflammatory medications, and responded better to aggressive treatment within the first week.

Bronchial bleeding caused by recurrent pneumonia after radical esophagectomy for esophageal cancer

We herein report a case of bronchial bleeding after radical esophagectomy that was treated with lobectomy. A 65-year-old male who underwent subtotal esophagectomy with three-field lymph node dissection for esophageal carcinoma was referred to our hospital because of sudden hemoptysis. After the esophagectomy, bilateral vocal cord paralysis was observed, and the patient suffered from repeated episodes of aspiration pneumonia. Bronchoscopy revealed hemosputum in the right middle lobe bronchus, and contrast-enhanced computed tomography showed tortuous arteries arising from the right inferior phrenic artery and left subclavian artery toward the right middle lobe bronchus. Although bronchial arterial embolization was performed twice to control the recurrent hemoptysis, the procedures were unsuccessful. Right middle lobectomy was therefore performed via video-assisted thoracic surgery. Engorged bronchial arterys with medial hypertrophy and overgrowth of the small branches were noted near the bronchus in the resected specimen. The patient recovered uneventfully and was discharged on postoperative day 14.

Ten years' experience in surgical treatment of right middle lobe syndrome

PURPOSE

In this study we present the clinical, radiological, pathological, bronchoscopic and surgical results of 40 patients with diagnosis of middle lobe syndrome who were referred to our thoracic surgery unit for surgical intervention in a 10 years period.

METHODS

Forty patients with obstructive and non-obstructive causes of middle lobe syndrome referred to our thoracic surgery unit. Clinical data were collected from the patients' records in a ten years period. This study evaluates diagnostic approaches and surgical treatments in right middle lobe syndrome.

RESULTS

We studied 23 females (57.5%) and 17 males (42.5%) with a mean age of 31.7. Clinical findings were cough 95%, sputum 80% and intermittent hemoptysis in 50% of patients. Middle lobe collapse was seen in CT scan of all patients. Bronchiectasis was the most common pathologic finding (55%). Tuberculosis was not rare and was final pathology in 20% of patients. In three patients ruptured hydatid cyst was final finding. Surgery was done without mortality and with only minor complications.

CONCLUSION

Lobectomy of right middle lobe is a good therapeutic option in these patients. Due to high prevalence of tuberculosis and hydatid cyst in Middle Eastern countries these two must be considered as causes of middle lobe syndrome.

Middle lobe syndrome in children today

Middle lobe syndrome in children is a distinct clinical and radiographic entity that has been well described in the pediatric literature. However, issues regarding its etiology, clinical presentation, and management continue to puzzle the clinical practitioner. Pathophysiologically, there are two forms of middle lobe syndrome, namely obstructive and nonobstructive. Middle lobe syndrome may present as symptomatic or asymptomatic, as persistent or recurrent atelectasis, or as pneumonitis or bronchiectasis of the middle lobe and/or lingula. A lower threshold of performing a chest radiograph is warranted in children with persistent or recurrent nonspecific respiratory symptoms, particularly if there is clinical deterioration, in order to detect middle lobe syndrome and to initiate a further diagnostic and therapeutic workup.

Middle lobe syndrome: a review of clinicopathological features, diagnosis and treatment

Middle lobe syndrome (MLS) is a rare but important clinical entity that has been poorly defined in the literature. It is characterized by recurrent or chronic collapse of the middle lobe of the right lung but can also involve the lingula of the left lung. Pathophysiologically, there are two forms of MLS, namely obstructive and nonobstructive. Obstructive MLS is usually caused by endobronchial lesions or extrinsic compression of the middle lobe bronchus such as from hilar lymphadenopathy or tumors of neoplastic origin, resulting in postobstructive atelectasis and pneumonitis. In the nonobstructive type, no obstruction of the middle lobe bronchus is evident during bronchoscopy or with computerized tomography of the chest. The etiology of the nonobstructive form is not completely understood. Inefficient collateral ventilation, infection and inflammation in the middle lobe or lingula are thought to play a role, and bronchiectasis is the most common histological finding. Patients with proven endobronchial lesions or malignancy are usually offered surgical resection directly. This contrasts with nonobstructive MLS, where most patients respond to medical treatment consisting of bronchodilators, mucolytics and broad-spectrum antibiotics. However, some patients do not respond to conservative treatment and may suffer irreversible damage of the middle lobe or lingula, in addition to having recurrent symptoms of infection or inflammation. These selected patients can be offered surgical resection of the middle lobe or lingula, which is associated with a low mortality rate and favorable outcome.