An enhanced regimen as post-exposure chemoprophylaxis for leprosy: PEP+.

The ongoing transmission of Mycobacterium (M.) leprae reflected in a very slow decline in leprosy incidence, forces us to be innovative and conduct cutting-edge research. Single dose rifampicin (SDR) as post-exposure prophylaxis (PEP) for contacts of leprosy patients, reduces their risk to develop leprosy by 60%. This is a promising new preventive measure that can be integrated into routine leprosy control programmes, as is being demonstrated in the Leprosy Post-Exposure Programme that is currently ongoing in eight countries.The limited (60%) effectiveness of SDR is likely due to the fact that some contacts have a preclinical infection beyond the early stages for which SDR is not sufficient to prevent the development of clinical signs and symptoms of leprosy. An enhanced regimen, more potent against a higher load of leprosy bacteria, would increase the effectiveness of this preventive measure significantly.The Netherlands Leprosy Relief (NLR) is developing a multi-country study aiming to show that breaking the chain of transmission of M. leprae is possible, evidenced by a dramatic reduction in incidence. In this study the assessment of the effectiveness of an enhanced prophylactic regimen for leprosy is an important component. To define the so called PEP++ regimen for this intervention study, NLR convened an Expert Meeting that was attended by clinical leprologists, public health experts, pharmacologists, dermatologists and microbiologists.The Expert Meeting advised on combinations of available drugs, with known efficacy against leprosy, as well as on the duration of the intake, aiming at a risk reduction of 80-90%. To come to a conclusion the Expert Meeting considered the bactericidal, sterilising and bacteriostatic activity of the potential drugs. The criteria used to determine an optimal enhanced regimen were: effectiveness, safety, acceptability, availability, affordability, feasibility and not inducing drug resistance.The Expert Meeting concluded that the enhanced regimen for the PEP++ study should comprise three standard doses of rifampicin 600 mg (weight adjusted when given to children) plus moxifloxacin 400 mg given at four-weekly intervals. For children and for adults with contraindications for moxifloxacin, moxifloxacin should be replaced by clarithromycin 300 mg (weight adjusted).

A 5-year evaluation of chemoprophylactic treatment in elementary school children with subclinical leprosy.

Subclinical leprosy is an infectious disease in which the immune system remains infected with Mycobacterium leprae (M. leprae). The progress of subclinical leprosy to clinical cases within 1 year of infection is 1.5%, with an increase to 6% in the following 4 years. Rifampicin is frequently used for prevention of leprosy, and clarithromycin has a bactericidal effect on M. leprae. Thus, the combination of both is expected to improve disease control in patients with subclinical leprosy. The aim of the present study was to evaluate the efficacy of a chemoprophylactic treatment involving rifampicin and clarithromycin against subclinical leprosy in elementary school children from endemic areas of East Java over a 5-year period. The study was performed between 2011 and 2015. Samples were collected from 2,548 healthy elementary school children in Nguling (Pasuruan) and Raas (Sumenep), and analysed using ELISA for anti-PGL (phenolic glycolipid)-1 IgM antibodies. Children who were seropositive for anti-PGL-1 IgM antibodies received a chemoprophylactic regimen consisting of rifampicin (300 mg/day) and clarithromycin (250 mg/day) daily for the initial 10 days, followed by the same regimen every 2 weeks for 3 months. Clinical and serological evaluations were performed annually for 5 years. Amongst the 2,548 healthy elementary school children, 200 were seropositive. The anti-PGL-1 IgM antibody levels significantly decreased between 2011 and 2015 in Nguling (from 1,066.7 to 137.4 U/ml) and Raas (from 773.1 to 563.4 U/ml), the levels decreased every year. In addition, the proportion of patients with decreased anti-PGL-1 IgM antibody levels was consistently higher than patients with increased anti-PGL-1 IgM antibody levels in all periods, except during 2013-2014, in Nguling and Raas. Chemoprophylactic treatment involving rifampicin and clarithromycin may thus be effective against subclinical leprosy amongst elementary school children.

Leprosy transmission in endemic and non-endemic areas based on the profile of antibody response of PGL-1 and PCR detection of Mycobacterium leprae DNA from nasal swab among healthy children of East Java, Indonesia.

Background: East Java has become one of the provinces that have higher prevalence of leprosy, especially in the coastal region. Environment has also influenced for leprosy transmission and early detection could reduce the incidence rate of new leprosy cases. Epidemiological studies of leprosy in children can give an illustration of the important aspects of the environment. Presence of Mycobacterium leprae (M. leprae) DNA in nasal swabs and seropositivity level among them can describe M. leprae exposure in that area. Objective: Analyzing PCR from nasal swab and seropositivity level among elementary school children between northern coast and southern coast of East Java province. Methods: Five hundred and thirty children in Pacitan and Lamongan were involved. Both areas are representation of northern and southern coastal region in East Java Province. After clinical examination, nasal swab and blood samples were obtained. ELISA test was performed to measure the titer of IgM anti Phenolic Glicolipid-1 (PGL-1) antibody then continued by PCR to detect M. leprae DNA. Results: From 301 students in Pacitan, 25 students (8.3%) are sero-positives and 9 students (2.9%) are PCR positives. from 229 students in Lamongan, 110 (48,3%) students are sero-positives and 49 students (21.4%) are PCR positives. Both are analyzed by Chi-Square, and from the PCR and ELISA, it concluded that there are statistically significant differences between the two regions. Conclusion: From study above shows that in the northern coast of East Java, incidence of subclinical leprosy is still high, it means that in this area still has a high risk of new cases of leprosy in the future and early detection tools need to performed as a preventative measure.

ACANTHAMOEBA SP.S-11 PHAGOCYTOTIC ACTIVITY ON MYCOBACTERIUM LEPRAE IN DIFFERENT NUTRIENT CONDITIONS.

BACKGROUND: Mycobacterium leprae (M. leprae) is a pathogenic bacterium that causes leprosy. The presence of M. leprae in the environment is supported by microorganisms that act as the new host for M. leprae. Acanthamoeba's potential to be a host of M. leprae in the environment. Acanthamoeba sp. is Free Living Amoeba (FLA) that classified as holozoic, saprophytic, and saprozoic. The existence of nutrients in the environment influence Acanthamoeba ability to phagocytosis or pinocytosis. This study is aimed to determine Acanthamoeba sp.S-11 phagocytic activity to Mycobacterium leprae (M. leprae) which cultured in non-nutrient media and riched-nutrient media. MATERIALS AND METHODS: This research conducted by culturing Acanthamoeba sp.S-11 and M. leprae on different nutrient media conditions. M. leprae intracellular DNA were isolated and amplified by M. leprae specific primers through Real Time PCR (Q-PCR). RESULT: The results showed that Acanthamoeba co-cultured on non-nutrient media were more active to phagocyte M. leprae than on rich-nutrient media. CONCLUSION: The use of non-nutrient media is recommended to optimize Acanthamoeba sp. phagocytic activity to M. leprae.

Identification of trehalose dimycolate (cord factor) in Mycobacterium leprae.

Glycolipids of Mycobacterium leprae obtained from armadillo tissue nodules infected with the bacteria were analyzed. Mass spectrometric analysis of the glycolipids indicated the presence of trehalose 6,6'-dimycolate (TDM) together with trehalose 6-monomycolate (TMM) and phenolic glycolipid-I (PGL-I). The analysis showed that M. leprae-derived TDM and TMM possessed both alpha- and keto-mycolates centering at C78 in the former and at C81 or 83 in the latter subclasses, respectively. For the first time, MALDI-TOF mass analyses showed the presence of TDM in M. leprae.

Expression profile of Rab5, Rab7, tryptophan aspartate-containing coat protein, leprae lipoarabinomannan, and phenolic glycolipid-1 on the failure of the phagolysosome process in macrophages of leprosy patients as a viability marker of Mycobacterium leprae.

OBJECTIVE/BACKGROUND: Phagolysosome process in macrophage of leprosy patients' is important in the early phase of eliminating Mycobacterium leprae invasion. This study was to clarify the involvement of Rab5, Rab7, and trytophan aspartate-containing coat protein (TACO) from host macrophage and leprae lipoarabinomannan (Lep-LAM) and phenolic glycolipid-1 (PGL-1) from M. leprae cell wall as the reflection of phagolysosome process in relation to 16 subunit ribosomal RNA (16S rRNA) M. leprae as a marker of viability of M. leprae. METHODS: Using a cross sectional design study, skin biopsies were obtained from 47 newly diagnosed, untreated leprosy at Dr Soetomo Hospital, Surabaya, Indonesia. RNA isolation and complementary DNA synthesis were performed. Samples were divided into two groups: 16S rRNA M. leprae-positive and 16S rRNA M. leprae-negative. The expressions of Rab5, Rab7, TACO, Lep-LAM, and PGL-1 were assessed with an immunohistochemistry technique. RESULT: Using Mann-Whitney U analysis, a significant difference in the expression profile of Rab5, Rab7, Lep-LAM, and PGL-1 was found (p<.05), but there was no significant difference of TACO between the two groups (p>.05). Spearman analysis revealed that there was a significant correlation between the score of Rab5, Rab7, Lep-LAM, and PGL-1 and the score of 16S rRNA M. leprae (p<.05). CONCLUSION: In M. leprae infection, Rab5, Rab7, and Lep-LAM play important roles in the failure of phagolysosome process via a membrane trafficking pathway, while PGL-1 plays a role via blocking lysosomal activities. These inventions might be used for the development of an early diagnostic device in the future.

[Global situation of leprosy and recent progress in molecular epidemiology of the disease].

Recent discovery of genetic diversity of Mycobacterium leprae such as variable number of tandem repeats opened a new era in molecular epidemiology of leprosy infection. It was revealed that the leprosy bacillus in residential environment of endemic villages is an important source of infection. The global elimination strategy will be revised taking new molecular epidemiological knowledge into account. Responsibility of leprosy specialist is to propose feasible control program to local administration based on the epidemiological analysis on transmission of the disease.

Genotyping of Mycobacterium leprae on the basis of the polymorphism of TTC repeats for analysis of leprosy transmission.

The polymorphism of TTC repeats in Mycobacterium leprae was examined using the bacilli obtained from residents in villages at North Maluku where M. leprae infections are highly endemic (as well as from patients at North Sulawesi of Indonesia) to elucidate the possible mode of leprosy transmission. TTC genotypes are stable for several generations of passages in nude mice footpads and, hence, are feasible for the genotyping of isolates and epidemiological analysis of leprosy transmission. It was found that bacilli with different TTC genotypes were distributed among residents at the same dwelling in villages in which leprosy is endemic and that some household contacts harbored bacilli with a different genotype from that harbored by the patient. Investigations of a father-and-son pair of patients indicated that infections of bacilli with 10 and 18 copies, respectively, had occurred. Genotypes of TTC repeats were found to differ between a son under treatment and two brothers. These results reveal the possibility that in addition to exposure via the presence of a leprosy patient with a multibacillary infection who was living with family members, there might have been some infectious sources to which the residents had been commonly exposed outside the dwellings. A limited discriminative capacity of the TTC polymorphism in the epidemiological analysis implies the need of searching other useful polymorphic loci for detailed subdivision of clinical isolates.