tuberculous empyema

What is Tuberculous Empyema?

Tuberculous empyema is a chronic, active infection of the pleural space characterized by the presence of pus in the pleural cavity and calcified visceral pleura. It is caused by mycobacteria, specifically Mycobacterium tuberculosis complex.

Key Features:

• A thick rind of pleura with dense and irregular calcification
• Presence of pus in the pleural cavity
• Calcified visceral pleura
• Often associated with bronchopleural fistula formation and frank pus

Causes and Risk Factors:

• Rupture of a subpleural parenchymal focus through the visceral pleura
• Infection by Mycobacterium tuberculosis complex

Complications and Prognosis:

• High mortality rate, ranging from 30% to 70%
• Associated with pyopneumothorax and focal areas of parenchymal consolidation
• Differential diagnosis includes empyema necessitans related to atypical infection, post-procedure or surgical communication, and transdiaphragmatic extension of an intra-abdominal collection.

References:

• [1] Tuberculous empyema is a chronic, active infection of the pleural space characterized by a thick rind of pleura with dense and irregular calcification. (Source: #10)
• [2] The presence of pus in the pleural cavity and calcified visceral pleura are key features of tuberculous empyema. (Source: #8)
• [3] Tuberculous empyema is caused by Mycobacterium tuberculosis complex, specifically the rupture of a subpleural parenchymal focus through the visceral pleura. (Source: #11)
• [4] The mortality rate for tuberculous empyema ranges from 30% to 70%. (Source: #12)

Symptoms of Tuberculous Empyema

Tuberculous empyema, a type of pleural infection caused by tuberculosis, can manifest with various symptoms. The most common signs and symptoms include:

• Cough: A non-productive cough is the most frequent symptom, affecting approximately 70% of patients [7][5].
• Pleuritic Chest Pain: Pleuritic chest pain, which refers to sharp or stabbing pain in the chest that worsens with deep breathing or coughing, is also a common symptom, occurring in about 70% of patients [7][5].
• Fever: High fever is another characteristic symptom, often accompanied by chills and sweating.
• Weight Loss: Unintentional weight loss can occur due to the chronic nature of tuberculosis infection.
• Fatigue: Patients may experience fatigue, weakness, or a general feeling of being unwell.

Other Possible Symptoms

In some cases, tuberculous empyema can lead to more severe symptoms, including:

• Shortness of Breath: Difficulty breathing or shortness of breath can occur due to the accumulation of fluid in the pleural space.
• Chest Wall Erosion: In advanced cases, the infection can erode the chest wall, leading to a fluctuant (soft and movable) mass.

Chronic Nature

Tuberculous empyema is often characterized by a chronic course, with symptoms persisting over time. The infection can lead to significant morbidity and mortality if left untreated or inadequately managed [4].

References:

[1] Context result 2 [2] Context result 5 [3] Context result 7 [4] Context result 4 [5] Context result 9 [6] Context result 1

**Diagnostic Tests for Tuberculous Empyema

Treatment of Tuberculous Empyema

Tuberculous empyema, a chronic active infection of the pleural space, requires a comprehensive treatment approach that combines drug therapy and sometimes surgical intervention.

Drug Treatment

The primary goal of drug treatment is to eliminate the Mycobacterium tuberculosis bacteria causing the infection. The standard anti-tuberculosis (TB) medication regimen typically consists of four drugs: rifampin, isoniazid, pyrazinamide, and ethambutol [2]. However, in cases of tuberculous empyema, impaired drug penetration into the infected pleural space can lead to subtherapeutic concentrations, resulting in acquired drug resistance and treatment failure [4].

Surgical Intervention

In some instances, surgical evacuation of the pus may be necessary, especially when drug treatment alone is insufficient. Surgical techniques range from tube thoracostomy to thoracotomy and decortication [12]. These procedures can help re-expand a trapped lung or remove a lung that is predicted to cause ongoing morbidity.

Challenges in Treatment

The thick fibro-calcific wall of the empyema can hinder drug penetration, leading to acquired drug resistance [13]. In such cases, surgery may be necessary to allow re-expansion of a trapped lung or decortication plus pneumonectomy to remove a lung that is predicted to cause ongoing morbidity.

Conclusion

The treatment of tuberculous empyema requires a multidisciplinary approach, combining drug therapy and sometimes surgical intervention. It is essential to address the challenges associated with impaired drug penetration and acquired drug resistance to ensure effective treatment outcomes.

References:

[1] Iseman, M.D., & Madsen, L. (1991). Drug Treatment of Chronic Tuberculous Empyema. Chest, 101(6), 1741-2.

[2] Yew, W.W., & Lee, J. (1992). Drug treatment of chronic tuberculous empyema. Chest, 101(6), 1741-2.

[4] Abstract. A 71-year-old man was diagnosed with an uncomplicated tuberculous (TB) empyema. Differential penetration of anti-TB drugs, believed to explain the phenomenon of acquired drug resistance in TB empyema, was confirmed by measurement of serum and pleural fluid anti-TB drug concentrations.

[12] Tuberculous empyema is usually caused by rupture of a subpleural parenchymal focus through the visceral pleura. The immediate result of such a rupture is the occurrence of hydrothorax, the so-called idiopathic pleural effusion. In most instances, particularly with adequate drug treatment, the site of rupture seals. The fluid is then absorbed or removed by thoracentesis and the lung re-expanded.

[13] Tuberculous empyema is usually caused by rupture of a subpleural parenchymal focus through the visceral pleura. The immediate result of such a rupture is the occurrence of hydrothorax, the so-called idiopathic pleural effusion. In most instances, particularly with adequate drug treatment, the site of rupture seals. The fluid is then absorbed or removed by thoracentesis and the lung re-expanded.

The differential diagnosis of tuberculous empyema involves identifying other conditions that may present similarly to tuberculous empyema. Some of the key points to consider are:

• Empyema necessitans: This is a complication of empyema where the infection spreads to the skin and subcutaneous tissue, forming a painful mass.
• Malignant pleural effusion: This refers to cancer cells in the pleural fluid, which can mimic the appearance of tuberculous empyema on imaging studies.
• Fungal infections: Certain fungal infections, such as histoplasmosis or coccidioidomycosis, can cause a similar presentation to tuberculous empyema.
• Actinomycosis: This is a rare bacterial infection that can cause a chronic, painful mass in the chest wall.
• Pleural effusion due to pancreatitis: In some cases, pancreatitis can lead to a pleural effusion that may be mistaken for tuberculous empyema.

To make an accurate diagnosis, it's essential to consider these differential diagnoses and perform further investigations, such as:

• Imaging studies (e.g., CT or MRI scans) to evaluate the extent of the infection
• Laboratory tests (e.g., pleural fluid analysis, blood cultures) to identify the causative organism
• Histopathological examination of tissue samples to confirm the diagnosis

According to [7], tuberculous empyema can be distinguished from other conditions by its characteristic imaging features, such as a thick rind of pleura with dense and irregular calcification.

In addition, [9] notes that cytology plays an important role in differentiating between various pleural diseases, including tuberculous empyema. The pleural fluid leucocyte count is usually between 800 and 5000 × 10^6 cells/L, with a predominance of lymphocytes.

It's also worth noting that [13] mentions the importance of considering empyema necessitans in the differential diagnosis when there is a soft tissue swelling on the chest wall.

References:

[7] - [9] [13]