Sputum examination for acid-fast bacilli in private laboratories, Kathmandu Valley, Nepal

To investigate the characteristics of private laboratories and the process of sputum examination for acid-fast bacilli (AFB).

A door-to-door survey of private laboratories in an urban municipality of Kathmandu valley was conducted during the first quarter of 1998. Semi-structured interviews were conducted with staff of 14/20 (70%) identified laboratories.

All 14 private laboratories conducted sputum examination for AFB. The majority (71%) of staff lacked special training for AFB examinations. Monocular microscopes were commonly used (36%). Reagents were prepared irregularly, without quality control, and kept for as long as they lasted, often up to 4-6 months (43%). Laboratory registers were usually present (86%), but lacked information on patient's address and the purpose of the test. A median of 12.5 slides per laboratory had been examined during the previous month (range 0-70). A total of 235 AFB slides were examined, of which 18 (7.7%) were reported as positive.

AFB examinations were widely available. Lack of training and quality control suggest a variable standard of AFB test results. It is recommended that the National Tuberculosis Programme (NTP) provide support and quality control to two to three (i.e., one for every 10) private laboratories in the area to secure private doctors' confidence in sputum testing.