Leprosy Mailing List – January 8, 2017
Ref.: (LML) Chemoprophylaxis in Leprosy
From: Carlos Gustavo Wambier, Ponta Grossa, Brazil
If the specialists are so concerned with "prophylaxis" with rimfampicin to household contacts, then they should have panicking concerns about induction of resistance with the actual WHO MB MDT, which recommends single monthly dose of a drug with a short half life of 3.5h FOR ONLY 12 doses.
In my humble point of view, this is the pathway to resistance, since this unique abx therapy in medicine accomplished what it is the most dangerous point on any antibiotic treatment: low concentration (single dose) and short period of exposure of the bacilli the drug. The drug does not even reach blood steady state concentrations for a person with zillions of mycobacteria. Moreover, some patients with impaired peripheral arterial circulation or fibrosis, may have lower concentration in their cold extremities, bones, and nerves.
The theoretical problem of "emergence" of resistance by actually fighting subclinical infection is far less important than what is currently recommended for the treatment of MB patients, with only 12 doses of the most active drug.
I would at least recommend this scheme to be changed for 12 consecutive days, so we could detect the relapse earlier!
CDC and NIH have a good point to give daily rifampicin. Instead of focusing on criticism on valid efforts to eradicate the disease, such as chemoprophylaxis, when should fight to start at least some consecutive days of rifampicin per month or switch to drugs with longer half life.
The assumption that the M.leprae and M.lepromatosis have a slow replication rate to explain single monthly dose is easily opposed by insufficient drug tissue concentration. Maybe to really eliminate leprosy, with the lack of diagnosis abilities of many physicians and what is worse, paramedicals worldwide, it would be more interesting to give full MB MDT for all, including contacts. And with extra steady-state rifampicin for patients with peripheral artery disease, lymphedema, fibrotic feet, and LL cases.
"Insanity: doing the same thing over and over again and expecting different results."
It is time for a change.
Carlos Gustavo Wambier, MD, PhD
Adjunct Professor of Dermatology
Department of Medicine
State University of Ponta Grossa
LML - S Deepak, B Naafs, S Noto and P Schreuder
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