Category: Pulmonary medicine

In this article, we will discuss the Pathology and Clinical Features of Acute Empyema Thoracis. So, let’s get started.

Pathology

In acute empyema, there is accumulation of large amount of pleural fluid with many polymorphs, bacteria, and cellular debris. Fibrin gets deposited on both layers of pleura (visceral and parietal) and there is a tendency towards loculation. Later, as the disease progresses (empyema becomes chronic), fibroblasts grow from both the layers into the exudate resulting in adhesions of both the surfaces of pleura and form an inelastic membrane called thickened pleura or pleural peel.

Clinical Features

Patients with aerobic infection (parapneumonic pleural effusion) present with acute onset of fever with chills, productive cough with mucopurulent expectoration (bronchopleural fistula), dyspnea and chest discomfort.

Patients with anaerobic infection present with subacute illness with non-specific signs and symptoms such as weight loss, leucocytosis, mild anemia and history of predisposing factor for aspiration from the oral cavity. Tubercular empyema presents with long-standing (for weeks and months) low-grade fever along with weakness and cough.

In acute phase, there are signs of toxemia such as fever, tachypnea, tachycardia, and pleural effusion. Presence of tenderness on percussion with some edema of the chest wall. Clubbing of fingers and toes are usually seen. Rarely there is a sign of empyema necessitans (empyema may track into the subcutaneous tissue of chest wall and presents as a localized swelling with positive cough impulse, and is mostly seen with actinomycotic infections).

Chronic cases present with pleural thickening and loculation of pus will show significant deformity with retraction of chest on the same side of empyema and even scoliosis. The signs will be dull percussion note with diminished breath sounds. extensive pleural calcification may occur. Tubercular empyema is often chronic and present with thickened pleura.