CT/USG guided biopsy in spinal tuberculosis: Diagnostic yield.

Area of Science:

• Orthopedics
• Infectious Diseases
• Radiology

Background:

• Spinal tuberculosis (STB) is a paucibacillary infection caused by Mycobacterium Tuberculosis.
• Delayed diagnosis of STB can result in significant morbidity and disability.
• Limited data exists on the diagnostic yield of various laboratory tests for STB evaluated via CT-guided biopsy or ultrasonography-guided aspiration.

Purpose of the Study:

• To evaluate the diagnostic yield of CT-guided biopsy and ultrasonography-guided aspiration for spinal tuberculosis.
• To compare the effectiveness of various phenotypic and molecular laboratory tests in diagnosing STB.
• To determine the optimal combination of tests for accurate STB diagnosis.

Main Methods:

• A study was conducted on 68 patients with clinico-radiologically suspected STB at a tertiary care center.
• Percutaneous aspiration (CT/USG-guided) was performed, and aspirated tissue/pus was sent for cytology, histopathology, culture, and molecular tests.
• The diagnostic yield of individual and combined phenotypic (histopathology, cytology, AFB smear) and molecular tests (CBNAAT, LPA) was calculated.

Main Results:

• Acid-fast bacilli (AFB) smear showed the lowest diagnostic yield (28% for USG, 17.2% for CT).
• A combination of histology/cytology with molecular methods achieved a 100% diagnostic yield.
• The combined approach using all tests also yielded 100% diagnostic accuracy.

Conclusions:

• A combination of molecular and phenotypic tests is essential for accurate STB diagnosis, as no single test is sufficient.
• Percutaneous CT-guided biopsy or USG-guided aspiration yields adequate tissue for comprehensive testing.
• The study highlights the effectiveness of combined diagnostic strategies for spinal tuberculosis.