Description
Overview
The BAL Fluid Analysis is a critical diagnostic procedure that “washes” a small segment of the lung to collect cells and fluid for examination. Unlike standard sputum tests, which only sample the upper airways, BAL retrieves samples directly from the alveoli (air sacs), providing a deeper insight into lung health.
Why is this test performed?
- Deep Lung Infections: To identify bacterial, viral, fungal, or mycobacterial (TB) infections that standard sputum tests miss, especially in immunocompromised patients.
- Interstitial Lung Disease (ILD): To investigate conditions like Sarcoidosis, Hypersensitivity Pneumonitis, or Pulmonary Fibrosis by analyzing specific cell patterns (e.g., lymphocyte or eosinophil counts).
- Unexplained Symptoms: To find the cause of persistent cough, unexplained lung infiltrates on X-rays, or coughing up blood (hemoptysis).
- Malignancy Screening: To check for the spread of lung cancer or lymphoma into the bronchial airways.
How it Works
This test is typically performed during a Bronchoscopy procedure by a pulmonologist:
- Insertion: A flexible bronchoscope (a thin, lighted tube) is passed through the nose or mouth into the lungs until it “wedges” into a specific airway.
- Lavaging (Washing): Sterile saline solution is gently instilled through the scope into the airway to wash the alveoli.
- Collection: The fluid is immediately suctioned back up. This fluid now contains lung cells, bacteria, and other substances from the deep lung tissue.
- Analysis: The sample is sent to the lab for cell counts, cultures, and cytological examination.
Test Details
- Sample Type: Bronchoalveolar Lavage Fluid (in a sterile container).
- Method: Cytology, Microbiology Culture, and Differential Cell Count.
- Preparation: Fasting is usually required for 6–12 hours before the bronchoscopy procedure.
- Turnaround Time: 24–72 hours (cultures may take longer).
