Leprosy Mailing List – October 24, 2017
Ref.: (LML) MDTU and the risk of emergence of resistant strains
From: Jaison Barreto, Bauru, Brazil
I would like to express my fear about the future of the leprosy treatment with MDT WHO. Recently, a paper was published about the effectiveness of 6 doses of MDT for all leprosy patients in some areas of Brazil. Unfortunately, the authors probably did not read any of the classical papers made in the last century.
- Ganapati (1992) compared the MDT 12 and 24 doses with a follow up of 1 to 5 year and did not find any difference in the effectiveness.
- Ji (1996) advocated the effectiveness of 3 to 6 months of MDT, but 5 years later (2001) published that patients with trillions of M.leprae (LL patients) who abandoned treatment had best results after 10 doses (less relapses).
- Jamet (1995) reported 7 relapses among 35 patients with high BI thet were treated with MDT 24 doses; the mean time interval for the occurence of relapses was 6 years.
- Girdhar (2000) found almost the same results among 561 patients, and showed that the more longer follow up, more relapses happened.
The time interval for a the appearance of single tuberculoid lesion is 3 to 5 years. The time interval for parasitism restricted to Schwann cell in a LL patient is 10 years. What about 1 to 5 years of follow up? The mean time of relapses of MDT 12 doses is 7 to 10 years in our service. For those treated with 24 doses, this time is 13 to 15 years.Avelleira (2003) evaluated 10 LL patients after 12 doses, and found that 3 patients had viable M. leprae in mouse foot pad assays.
What are five years of follow up for M. leprae?
I have seen many cases of relapses among LL patients treated with 12 doses.
In my PhD thesis, I found 4 relapses among 46 LL patients after 11 years of discharge treated with 24 doses in a non endemic area of Brazil, and 23% still had positive serology or PCR in nasal mucus.
I hope that leprologists do not accept experiments with leprosy patients without strong scientific basis, i.e., chronic diseases wrongly treated because the follow up was not long enough.
LML - S Deepak, B Naafs, S Noto and P Schreuder
LML blog link: http://leprosymailinglist.blogspot.it/
Contact: Dr Pieter Schreuder << email@example.com