What is the common presentation of intralobar pulmonary sequestration (ILPS)?

Intralobar Pulmonary Sequestration Most Commonly Presents with Recurrent Pneumonia

Intralobar pulmonary sequestration (ILPS) most commonly presents with recurrent pneumonia in the same lower lobe, which is the correct answer (c). This clinical presentation is the hallmark feature of this congenital anomaly and should prompt early diagnostic evaluation and surgical intervention.

Clinical Presentation of Intralobar Pulmonary Sequestration

• Recurrent pneumonia (90%): The vast majority of patients with ILPS present with a history of recurrent pulmonary infections in the same location, typically a lower lobe 1. This is the most characteristic presentation.

• Chronic cough: Persistent or intermittent cough is a common accompanying symptom 1, 2.

• Intermittent fevers: Often associated with infectious episodes 1.

• Hemoptysis: Can occur but is less common than recurrent infections. May become fatal if left untreated 3.

• Dyspnea and chest pain: Less common presenting symptoms compared to recurrent infections.

• Asymptomatic presentation: Rare, occurring in only about 10% of cases 1.

Diagnostic Approach

When a patient presents with recurrent infections in the same lower lobe, ILPS should be high on the differential diagnosis:

1. Chest radiography: Always abnormal in patients with ILPS, but findings are often nonspecific 1.

2. CT with IV contrast or CTA: The preferred imaging modality that can show:

   • Mass or consolidation with or without cystic changes 4
   • Identification of systemic arterial supply (pathognomonic finding) 5
   • Typically located in lower lobes (60-90%), more common in left lung 2

3. Thoracic arteriography: Helps visualize the systemic arterial supply from the thoracic or abdominal aorta to the sequestered lung tissue 1.

Key Diagnostic Features

• ILPS is characterized by non-functioning lung tissue that lacks normal communication with the tracheobronchial tree 4, 6.

• The sequestered lung tissue receives blood supply from an abnormal systemic artery, typically a branch of the descending aorta 4, 6.

• The condition shares the pleura with the parent lobe, distinguishing it from extralobar sequestration 6.

Management

• Surgical resection: The definitive treatment is surgical removal of the affected lobe (lobectomy) or segment (segmentectomy) 1, 2.

• Video-assisted thoracoscopic surgery (VATS): Minimally invasive approach that allows for early discharge and fewer complications 2.

• Preoperative imaging: Critical to identify the aberrant systemic arterial supply to prevent catastrophic bleeding during surgery 1.

Clinical Pitfalls

• Delayed diagnosis: The diagnosis is often delayed (mean 1.5 years, range 3 months to 7 years) due to misdiagnosis as recurrent pneumonia without identifying the underlying cause 1.

• Ineffective antibiotic treatment: Patients are often treated with multiple courses of antibiotics without addressing the underlying anatomical abnormality 1.

• Failure to suspect: A high index of suspicion is necessary in patients with recurrent infections in the same lower lobe to prompt appropriate diagnostic imaging 1.

Early recognition of the classic presentation of recurrent pneumonia in the same location should trigger appropriate diagnostic workup to identify this uncommon but distinct clinical entity, leading to definitive surgical management and prevention of complications.