UNLABELLED: The working hypothesis is that, viable Mycobacterium leprae (M. leprae) play a crucial role in the precipitation of Type 1 reaction (T1R) in leprosy.
MATERIAL AND METHODS: A total of 165 new multibacillary patients were studied. To demonstrate presence of viable M. leprae in reactional lesion (T1R+), three tests were used concurrently viz. growth in the mouse foot pad (MFP), immunohistochemical detection of M. leprae secretory protein Ag85, and 16s rRNA--using in situ RT-PCR. Mirror biopsies and non reactional lesions served as controls (T1R-).
FINDINGS: A significantly higher proportion of lesion biopsy homogenates obtained at onset, from T1R(+) cases have shown unequivocal growth in MFP, proving the presence of viable bacteria, as compared to T1R(-) (P < 0.005). In contrast, few Mirror biopsies were positive in both T1R(+) and T1R(-). With respect to Ag85, while the overall positivity was higher in T1R(+) (74%), however the intensity of staining (Grade 2+) was disproportionately higher in T1R(+) BT-BB lesions 11/20 (55%). In the rebiopsies obtained during a repeat episode of T1R, Ag 85 as well as 16s rRNA, positivity (62% & 100%) was higher in T1R(+). It is inferred therefore 'viable' bacteria are an essential component in T1R and difference in the quality of bacilli, not the quantity or the ratio of dead to viable play a role in the precipitation of T1R. In conclusion, the findings show that 'metabolically active' M. leprae is a component/prerequisite and the secretory protein Ag 85, might be the trigger for precipitation of T1R.
BT - Leprosy review C1 -http://www.ncbi.nlm.nih.gov/pubmed/27255061?dopt=Abstract
IS - 1 J2 - Lepr Rev LA - eng N2 -UNLABELLED: The working hypothesis is that, viable Mycobacterium leprae (M. leprae) play a crucial role in the precipitation of Type 1 reaction (T1R) in leprosy.
MATERIAL AND METHODS: A total of 165 new multibacillary patients were studied. To demonstrate presence of viable M. leprae in reactional lesion (T1R+), three tests were used concurrently viz. growth in the mouse foot pad (MFP), immunohistochemical detection of M. leprae secretory protein Ag85, and 16s rRNA--using in situ RT-PCR. Mirror biopsies and non reactional lesions served as controls (T1R-).
FINDINGS: A significantly higher proportion of lesion biopsy homogenates obtained at onset, from T1R(+) cases have shown unequivocal growth in MFP, proving the presence of viable bacteria, as compared to T1R(-) (P < 0.005). In contrast, few Mirror biopsies were positive in both T1R(+) and T1R(-). With respect to Ag85, while the overall positivity was higher in T1R(+) (74%), however the intensity of staining (Grade 2+) was disproportionately higher in T1R(+) BT-BB lesions 11/20 (55%). In the rebiopsies obtained during a repeat episode of T1R, Ag 85 as well as 16s rRNA, positivity (62% & 100%) was higher in T1R(+). It is inferred therefore 'viable' bacteria are an essential component in T1R and difference in the quality of bacilli, not the quantity or the ratio of dead to viable play a role in the precipitation of T1R. In conclusion, the findings show that 'metabolically active' M. leprae is a component/prerequisite and the secretory protein Ag 85, might be the trigger for precipitation of T1R.
PY - 2016 SP - 78 EP - 92 T2 - Leprosy review TI - Association of viable Mycobacterium leprae with Type 1 reaction in leprosy. UR - https://leprosyreview.org/article/87/1/07-8092 VL - 87 SN - 0305-7518 ER -