Application of HI test for dapsone in urine under field conditions

One hundred and two specimens of urine collected from leprosy patients attending the field clinics of Central Leprosy Teaching and Research Institute, Chingleput, Tamil Nadu, India, were screened for dapsone by the paper spot test and Haemagglutination Inhibition (HI) tests. A concordance of about 90% was observed between the two tests. Both tests showed their merits. The lower sensitivity of the spot test finds more cases of irregular compliance (1-2 days), whereas the higher sensitivity of the HI allows the demonstration of the intake of lower doses and the detection of those cases, who have grossly missed their tablets (longer than a week).