Isolation of Mycobacterium tuberculosis from faeces

Faeces from patients with Myco, tuberculosis in their sputum was decontaminated using NaOH, acid and an alkaline precipitation method. Treated specimens were diluted, to reduce the number of surviving normal flora, and cultured in liquid selective media. Sub-cultures were made on selective agar and Lowenstein-Jensen medium. Both alkaline methods were superior to acid treatment. Use of all three methods, dilution and culture, yielded growth of Myco, tuberculosis from 90% of patients' faeces, although previous reports have cited only 25-30% of patients excreting bacilli in their faeces.