Bacillary Index

 

Leprosy Mailing List – March 19 ,  2013

 Ref.:    (LML) Bacillary Index

From:  Dr. Jaison Barreto, Bauru, Brazil

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Dear Pieter

 

 

I agree with Dr Andrea that bacilloscopy is dependent on several aspects.

 

The first and most important is the health professional's knowledge about the disease. Nowadays, leprosy is not more considered as a complex disease and even, in research centers, it is classified only as PB or MB. But a complex disease as leprosy should be classified according to 5 criteria: clinical, immunological, histopathological, bacilloscopical and, no less important, evolutive aspects. If this is not possible, all case should be treated as MB, like we do with tuberculosis.

 

What is PB leprosy? In few words, one could say that is this classification should be reserved for patients with few bacilli because they are on the beginning of their disease (indeterminate leprosy), or for those who have cellular immunity enough to destroy all bacilli even without MDT, i.e., have the pattern of true tuberculoid leprosy (TT). Though TT and BT leprosy are very similar clinically and histopathologically, the prognosis is not the same. Usually, BT patients have few bacilli inside skin but have many in nerve fibers/nerve trunks, due to the neural-blood barrier, nerve branches are a "sanctuary". Also, according to Ridley, BT tends to BL, and most BL comes from BT, as well as most subpolar LL are, i.e., all comes from borderline leprosy. True TT is rare, as well as true (polar) LL.

 

Unfortunately, we all know that M.leprae can stay alive inside Schwann cells for many years. This is, probably, the reason why patients with indeterminate (or early) leprosy, who are histopathologically and bacilloscopically PB, when they do not have a cellular response to the bacilli, i.e. have a  lepromine negative reaction, often show a relapse 7 to 10 years after discharge. So, even in patients with the same disease, as indeterminate leprosy, can have a different prognosis, and actually should be treated with different regimens.

 

Finally, bacilloscopy, for diagnosis, should be done only in cases suspected to be LL, who have bacilli in all the skin surface, or suspect to be borderline, when the bacilli, initially, are only INSIDE THE MACROPHAGES OF THE LESION, and not on index points( c.q. these are areas outside the lesions were no bacilli are found)

 

 

Regards

 

Jaison

 

 

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 LML - S Deepak, B Naafs, S Noto and P Schreuder
LML Archives: temporary not available, until further notice.
Contact: Dr Pieter Schreuder << editorlml@gmail.com >>.

p/s. The attached file (SSS examination report) is from Dr. Andrea, San Martino, Genoa, Italy, which we have been trying unsuccessfully to send to you.