Fluid For C/S

Function

The Culture and Sensitivity (C/S) test on body fluids is a critical microbiological procedure used to identify the presence of pathogenic microorganisms (bacteria or fungi) in normally sterile body compartments. This includes fluids like pleural fluid (lungs), ascitic fluid (abdomen), or synovial fluid (joints).

Why it is Ordered

It is ordered when an infection is suspected in a specific cavity, a condition known as an 'effusion.' If a patient presents with localized swelling, pain, and fever, clinicians must determine if the fluid accumulation is 'sterile' (due to inflammation or pressure) or 'infected' (due to bacteria). The sensitivity portion of the test is vital, as it determines which specific antibiotics will effectively kill the identified pathogen.

Associated Conditions

• Septic Arthritis: Infection in a joint space.
• Bacterial Peritonitis: Infection of the abdominal lining, common in patients with liver cirrhosis.
• Empyema: A collection of pus in the pleural space (around the lungs).
• Meningitis: If the fluid is Cerebrospinal fluid (CSF).

Procedure Overview

The fluid is incubated in growth media. If growth occurs, it is identified using biochemical tests or mass spectrometry, and then tested against various antibiotic discs to observe zones of inhibition.