Bartonella henselae DNA detection in patients with type 1 leprosy reactions for more than six months

Leprosy reactions are among the main causes of physical disability resulting from an infectious disease and can culminate in irreversible physical disabilities, therefore they should be considered a clinical emergency, as well as the elucidation of its cause. Co-infections are considered one of the main triggering causes of leprosy reactions, aggravating and maintaining these reactions for longer in these patients. After reporting a high rate of Bartonella henselae infection in patients with chronic type 2 leprosy reaction, 19/47 (40.4 %) compared to the control group, 9/50 (18.0 %), p = 0.0149, we conducted this study to observe the rate of infection by Bartonella sp. in a group of patients with chronic type 1 leprosy reactions. Blood samples from 14 patients with chronic type 1 leprosy reactions were analyzed by molecular and microbiological tests and compared. The results showed that, like patients with chronic type 2 leprosy reactions, this group of patients has a high proportion of B. henselae infection 6/14 (42.9 %), p = 0.88. We conclude that these bacteria can trigger chronic leprosy reactions and should be investigated in all chronic leprosy reactions patients. Summary Line: Our results showed that, like patients with chronic type 2 leprosy reactions, this group of patients has the same proportion of B. henselae DNA detection 6/14 (42.9 %), p = 0.88.

Adverse reactions induced by MDT/WHO (Rifampicin+Clofazimine+Dapsone) and ROM (Rifampicin+Ofloxacin+Minocycline) regimens used in the treatment of leprosy: a cohort study in a National Reference Center in Brazil

Background: Recommended standard treatment for leprosy is multidrugtherapy (MDT/WHO), consisting Rifampicin+Dapsone+Clofazimine. Other medications are recommended in cases of resistance, adverse reactions and intolerances, including ROM regimen, Rifampicin+Ofloxacin+Minocycline. Therefore, pharmacovigilance is an important tool in understanding these adverse drug reactions (ADRs), supporting pharmacotherapy management and medication safety. This study seeks to evaluate ADRs comparing two therapeutic regimens, MDT and ROM, used in treatment of patients with leprosy, analyzing prognostic factors regarding risk and safety. Methods:A retrospective cohort study was performed by assessing medical records of 433 patients diagnosed with leprosy from 2010 to 2021 at a National Reference Center in Brazil. They were subject to 24 months or more of treatment with MDT or ROM regimens. ADR assessments were analyzed by two experienced researchers, who included clinical and laboratory variables, correlating them with temporality, severity and the causality criteria of Naranjo and WHO. Results: The findings observed an average of 1.3 reactions/patient. Out of individuals experiencing reactions, 67.0% (69/103) were utilizing MDT/MB, while 33.0% (34/103) were using ROM. The median time for ADR of 79 days for MDT and 179 days for ROM. In first reaction, Dapsone was the most frequently involved medication; the most affected system was hematopoietic. As compared to Clofazimine, results indicated that use of Dapsone was associated with 7% increased risk of ADR occurrence (HR: 1.07; p = 0.866). Additionally, Rifampicin was linked to 31% increased risk of ADRs (HR: 1.31; p = 0.602); and Ofloxacin showed 35% elevated risk (HR: 1.35; p = 0.653). Conversely, results for Minocycline indicated 44% reduction in the risk of ADRs (HR: 0.56; p = 0.527), although statistical significance was not reached. The use of MDT conferred 2.51 times higher risk of developing ADRs in comparison to ROM. Conclusion: The comparison between MDT and ROM revealed that MDT caused more ADRs, and these reactions were more severe, indicating less safety for patients. Dapsone was the most common medication causing ADRs, followed by Rifampicin. The combination with Clofazimine was associated with an additional risk of ADRs, warranting further studies to confirm this hypothesis. Given the high magnitude of ADRs, healthcare teams need to monitor patients undergoing leprosy treatment with focus on pharmacovigilance.

Description of electroneuromiographic and laboratorial findings in leprosy neuropathy, according to its clinical forms: the confirmation of a spectral disease

Introduction

Leprosy is one of the most common infectious cause of peripheral neuropathy in the world and can lead to sequelae and physical disabilities. Electroneuromyography (ENMG) is the gold-standard test for evaluating neural impairment, detecting from subclinical abnormalities to advanced lesions. This study aims to describe the electroneuromyographic findings in patients with leprosy, according to their clinical forms.

Methods

The study is a retrospective observational analysis of the medical records of patients with leprosy, of a National Reference Center of Sanitary Dermatology and Leprosy in Brazil between 2014 and 2022. 513 patients underwent ENMG at leprosy diagnosis and also underwent a clinical, serological and molecular evaluation of the disease.

Results

The electroneuromyographic findings showed 2,671 altered nerves, with an average of 6.9 (±5.1) altered nerves per patient. The most affected sensory nerves were the superficial peroneal (25.0%; 413/1649), sural (15.1%; 397/2627) and ulnar (13.8%; 363/2627), with average of 4.3 (±3.2) affected sensory nerves per patient. The most affected motor nerves were the ulnar (33.1%; 338/1022) and common peroneal (12.1%; 319/2627), with average of 2.6 (±2.5) motor nerves affected per patient. 126 patients presented normal ENMG and, among the 387 with abnormalities in the exam, 13.2% (51/387) had mononeuropathy and 86.8% (336/387) had multiple mononeuropathy. Axonal involvement was more frequent in primary neural leprosy, borderline-tuberculoid, borderline-lepromatous and lepromatous forms.

Discussion

Our findings support that leprosy is a spectral disease, characterized by a balance between host immunity and bacillary load. Therefore, the impairment and electroneuromyographic characteristics are distinct and may vary according to the clinical form.

Identification of types of wound bed tissue as a percentage and total wound area by planimetry in neuropathic and venous ulcers

BACKGROUND

Neuropathic and venous leg ulcers are chronic wounds associated with devitalized tissue and recurrent infection. Management should be guided by accurate tissue assessment, including the use of planimetry, which provides tissue types as a percentage of the total wound bed surface area.

OBJECTIVE

This innovative study aimed to assess and identify the wound bed tissues, as a percentage, of neuropathic and venous ulcers using digital planimetry, providing support to nurses optimize the management of necrotic tissues and, consequently, to avoid wound infection.

METHODS

This cross-sectional study enrolled 24 patients with chronic wounds who were assessed from January to March 2021 at the Wound Outpatients Clinic. The wound photographs were analyzed using Image J 1.53e and a smartphone with WoundDoc Plus® 2.8.2 via digital planimetry. Statistical analyses were performed using the binomial test, t-test, and Mann-Whitney.

RESULTS

Median wound areas (p=0.3263) did not differ between the group with 2 or 3 risk factors for delayed healing (Md: 31.7) and the group with up to 1 risk factor (Md: 5.3). A low exudate level was associated with the up-to-1-risk-factor-for-delayed-healing group (p=0.0405), while a medium level was associated with the two-or-three-risk-factor group (p=0.0247). A heat map displayed the tissue percentages in the wound bed. In the group with 2 or 3 risk factors for delayed healing, 91.7% (11/12) had less than 70% granulation tissue, which was the primary factor for this group (p<0.0001). Additionally, 66.7% (8/12) of patients with 2 or 3 risk factors for delayed healing exhibited discolored and/or dark red granulation tissue as the primary factor (p=0.0130).

CONCLUSION

This novel identification of wound area and tissue types as a percentage, using digital planimetry, can play a crucial role in assisting nurses in decision-making related to the appropriate management of devitalized tissues. Furthermore, this measurements may facilitate the conducting of virtual wound consultations and offer valuable support in the development of protocols aimed at preventing infection and biofilm formation in the wound bed.

Bartonella henselae as a putative trigger for chronic type 2 leprosy reactions

Leprosy reactions are an acute inflammatory phenomenon that can arise before diagnosis, during treatment, or after cure of leprosy. These reactions are considered one of the main diseases that cause physical disabilities. Immunosuppressive treatment for these immune responses makes these patients susceptible to coinfections, which can trigger new leprosy reactions. The main objective of this study was to evaluate the occurrence of infection by Bartonella sp. in blood samples from 47 patients who had untreatable episodes of type 2 leprosy reactions for more than six months, comparing them with a control group. Cultures and molecular methods (PCR) were used. Amplicons from species-specific reactions and sequencing showed a higher prevalence of Bartonella henselae infection in patients, 19/47 (40.4 %), compared to control, 9/50 (18.0 %), p = 0.0149. Five patients accepted treatment for coinfection, and all showed improvement in leprosy reactions with treatment for B. henselae infection. We conclude that these bacteria can trigger chronic reactions of type 2 leprosy and should be investigated in these patients. SUMMARY LINE: Patients who have chronic type 2 leprosy reactions are more susceptible to Bartonella henselae infection than controls: 19/47 (40.4 %) compared 9/50 (18.0 %), p = 0.0149.

HSP60 mimetic peptides from Mycobacterium leprae as new antigens for immunodiagnosis of Leprosy

The early diagnosis of leprosy serves as an important tool to reduce the incidence of this disease in the world. Phage display (PD) technology can be used for mapping new antigens to the development of immunodiagnostic platforms. Our objective was to identify peptides that mimic Mycobacterium leprae proteins as serological markers using phage display technology. The phages were obtained in the biopanning using negative and positive serum from household contacts and leprosy patients, respectively. Then, the peptides were synthesized and validated in silico and in vitro for detection of IgG from patients and contacts. To characterize the native protein of M. leprae, scFv antibodies were selected against the synthetic peptides by PD. The scFv binding protein was obtained by immunocapture and confirmed using mass spectrometry. We selected two phase-fused peptides, MPML12 and MPML14, which mimic the HSP60 protein from M. leprae. The peptides MPML12 and MPML14 obtained 100% and 92.85% positivity in lepromatous patients. MPML12 and MPM14 detect IgG, especially in the multibacillary forms. The MPML12 and MPML14 peptides had positivity of 11.1% and 16.6% in household contacts, respectively. There was no cross-reaction in patient's samples with visceral leishmaniasis, tuberculosis and other mycobacteriosis for both peptides. Given these results and the easy obtainment of mimetic antigens, our peptides are promising markers for application in the diagnosis of leprosy, especially in endemic and hyperendemic regions.

High-resolution ultrasonography for early diagnosis of neural impairment in seropositive leprosy household contacts

Leprosy household contacts (HC) represent a high-risk group for the development of the disease. Anti-PGL-I IgM seropositivity also increases the risk of illness. Despite significant advances in leprosy control, it remains a public health problem; and early diagnosis of this peripheral neuropathy represents one of the main goals of leprosy programs. The present study was performed to identify neural impairment in leprosy HC by analyzing differences in high-resolution ultrasonographic (US) measurements of peripheral nerves between leprosy HC and healthy volunteers (HV). Seventy-nine seropositive household contacts (SPHC) and 30 seronegative household contacts (SNHC) underwent dermato-neurological examination and molecular analysis, followed by high-resolution US evaluation of cross-sectional areas (CSAs) of the median, ulnar, common fibular and tibial nerves. In addition, 53 HV underwent similar US measurements. The US evaluation detected neural thickening in 26.5% (13/49) of the SPHC and only in 3.3% (1/30) among the SNHC (p = 0.0038). The CSA values of the common fibular and tibial nerves were significantly higher in SPHC. This group also had significantly greater asymmetry in the common fibular and tibial nerves (proximal to the tunnel). SPHC presented a 10.5-fold higher chance of neural impairment (p = 0.0311). On the contrary, the presence of at least one scar from the BCG vaccine conferred 5.2-fold greater protection against neural involvement detected by US (p = 0.0184). Our findings demonstrated a higher prevalence of neural thickening in SPHC and support the role of high-resolution US in the early diagnosis of leprosy neuropathy. The combination of positive anti-PGL-I serology and absence of a BCG scar can identify individuals with greater chances of developing leprosy neuropathy, who should be referred for US examination, reinforcing the importance of including serological and imaging methods in the epidemiological surveillance of leprosy HC.

Early diagnosis of neural impairment in seropositive leprosy household contacts: The experience of a reference center in Brazil

Introduction

Leprosy is an infectious disease that remains with a high number of new cases in developing countries. Household contacts have a higher risk for the development of the disease, but the neural impairment in this group is not well elucidated yet. Here, we measured the chance of occurrence of peripheral neural impairment in asymptomatic leprosy household.

Methods

Contacts who present anti-PGL-I IgM seropositivity, through electroneuromyography (ENMG) evaluation. We recruited 361 seropositive contacts (SPC) from 2017 to 2021, who were subjected to an extensive protocol that included clinical, molecular, and electroneuromyographic evaluations.

Results

Our data revealed a positivity of slit skin smear and skin biopsy qPCR of 35.5% (128/361) and 25.8% (93/361) respectively. The electroneuromyographic evaluation of the SPC showed neural impairment in 23.5% (85/361), with the predominance of a mononeuropathy pattern in 62.3% (53/85). Clinical neural thickening was observed in 17.5% (63/361) of seropositive contacts, but among the individuals with abnormal ENMG, only 25.9% (22/85) presented neural thickening in the clinical exam.

Discussion

Ours results corroborates the need to make the approach to asymptomatic contacts in endemic countries more timely. Since leprosy in its early stages can present an indolent and subclinical evolution, serological, molecular, and neurophysiological tools are essential to break the disease transmission chain.

Clinical, epidemiological, and laboratory prognostic factors in patients with leprosy reactions: A 10-year retrospective cohort study

Introduction

Leprosy reactions, the main cause of neural damage, can occur up to 7 years after starting multidrug therapy. We aimed to approach the prognostic factors that may influence the leprosy reactions over the follow-up time.

Methods

Retrospective cohort study, encompassing 10 years of data collection, composed of 390 patients, divided into 201 affected by reactions and 189 reaction-free individuals. Epidemiological, clinical, and laboratory variables were approached as prognostic factors associated with leprosy reactions. The association among variables was analyzed by a binomial test and survival curves were compared by the Kaplan-Meier and Cox proportional-hazards regression.

Results

51.5% (201/390) of patients were affected by leprosy reactions. These immunological events were associated with lepromatous leprosy (16.2%; 63/390; p < 0.0001) and multibacillary group (43%; 169/390; p < 0.0001). This study showed that survival curves for the prognostic factor anti-PGL-I, comparing positive and negative cases at diagnosis, differed in relation to the follow-up time (Log Rank: p = 0.0760; Breslow: p = 0.0090; Tarone-Ware: p = 0.0110). The median survival times (time at which 50% of patients were affected by leprosy reactions) were 5 and 9 months for those reactional cases with negative (26/51) and positive serology (75/150), respectively. The time-dependent covariates in the cox proportional-hazards regression showed anti-PGL-I as the main prognostic factor to predict leprosy reactions (hazard ratio=1.91; p = 0.0110) throughout the follow-up time.

Conclusions

Finally, these findings demonstrated that anti-PGL-I serology at diagnosis is the most important prognostic factor for leprosy reactions after starting multidrug therapy, thus enabling prediction of this immunological event.

Fever of Unknown Origin, Wasting Syndrome and Bone Marrow Involvement: A Leprosy Case Report

Mycobacterium leprae, the etiologic agent of leprosy, is an acid-fast-staining and slow-growing bacilli that infect macrophages and Schwann cells individually or through forming globi. The clinical presentation of leprosy is broad and depends on the host immune response. We report a case of a 42-year-old Brazilian man presenting with fever of unknown origin (FUO), anemia, wasting syndrome, and neuropathy. The diagnosis of lepromatous leprosy was made after an extensive investigation revealed the presence of M. leprae in the bone marrow. Bone marrow involvement in leprosy is rare and some authors believe the presence of M. leprae in the bone marrow can act as a reservoir of the disease facilitating future relapses. It is important to investigate bone marrow involvement in leprosy, especially when the patient presents with cytopenias and positive epidemiologic history.

Type 2 leprosy reaction presenting as a monoarthritis post multidrug therapy

Type 2 leprosy reaction, or erythema nodosum leprosum (ENL), involves a complex interaction between the host's immune system and Mycobacterium leprae. It may occur before, during, or after treatment and have a variable clinical presentation involving different body systems, such as skin, osteoarticular, kidneys, and others. Thus, the differential diagnosis, depending on its clinical presentation, can be broad and challenging. The authors report a case of a severe monoarthritis during a type 2 reaction after the multidrug therapy (MDT) was discharged and the investigation of the differential diagnoses.

Leprosy Relapse: a Retrospective Study on Epidemiological, Clinical and Therapeutics Aspects at a Brazilian Referral Center

OBJECTIVES

We aim to characterize the profile of patients diagnosed with leprosy relapse and understand the influence of different multidrug therapy (MDT) treatments and initial disease presentation.

METHODS

This retrospective study included patients diagnosed with leprosy relapse at a referral center in Brazil from 2013-2018. We analyzed their clinical-epidemiological characteristics, laboratory, and bacilloscopic tests. Survival analysis was used to determine the time elapsed until relapse, according to the previous treatment and the disease clinical forms.

RESULTS

126 cases of relapse were analyzed, which comprised 11.89% (126/1059) of the cases. The median time elapsed until relapse was 10 years, and most patients had previously undergone 12 doses of MDT (40.48%; 51/126). Undergoing 24 doses of MDT was associated with a better prognosis regarding relapse over time compared to six or 12 doses of MDT therapy. Most of the cases of relapse were classified as multibacillary (96.03%; 121/126).

CONCLUSION

The incidence of relapse was greater than observed in other studies. The high percentage of multibacillary patients who had negative bacillary indices demonstrated that the bacillary index cannot be considered to be an essential criterion for relapse, especially with regard to making an early diagnosis.

Late follow-up of peripheral neural decompression in leprosy: functional and clinical outcomes

BACKGROUND

Peripheral neural surgical decompression (PNSD) is used as a complementary therapy to the clinical treatment of neuritis to preserve neural function.

OBJECTIVE

To evaluate the long-term (≥ 1 year) clinical and functional results for PNSD in leprosy neuritis.

METHODS

This cross-sectional study included leprosy patients who were in late postoperative period (LPO) of surgical decompression of ulnar, median, tibial, and fibular nerves. Socioeconomic, epidemiological, and clinical data were collected. The following instruments were used in this evaluation: visual analogue pain scale (VAS), Douleur Neuropathique en 4 Questions (DN4), SALSA scale, and simplified neurological assessment protocol. The preoperative (PrO) and 180-day postoperative (PO180) results were compared.

RESULTS

We evaluated 246 nerves from 90 patients: 56.6% were on multidrug therapy (MDT) and 43.3% discharged from MDT. Motor scores and pain intensity showed statistically significant improvement (p<0.01). There was an increase in sensory scores only for bilateral ulnar nerves (p<0.05). Of the operated cases, 26.0% of patients were referred for surgery of ulnar neuritis and 23.6% of tibial neuritis. Neuropathic pain was reported in 41% of cases. Daily dose of prednisone reduced from 39.6 mg (±3.0) in PrO, 16.3 mg (±5.2) in PO180, to 1.7 mg (±0.8) in LPO. The SALSA scale results showed mild activity limitation in 51% and moderate in 34% of patients. Eighty percent of individuals reported that the results reached their expectations.

CONCLUSIONS

PNSD in leprosy was effective in the long term to decrease the prevalence and intensity of pain, improve motor function, and reduce the dose of corticosteroids, which is reflected in the patients' satisfaction.

Peripheral nerve biopsy: a tool still needed in the early diagnosis of neural leprosy?

BACKGROUND

The early recognition of neural impairment in leprosy, especially in primary neural forms, represents a challenge in clinical practice and a peripheral nerve biopsy may be required for diagnostic confirmation. This study aims to characterize the epidemiological, clinical, electroneuromyographic, laboratory and histopathological aspects of patients undergoing peripheral nerve biopsy during investigation of primary neural cases in leprosy.

METHODS

A total of 104 patients with peripheral neuropathy who were referred to a national reference centre for leprosy were biopsied from 2014 to 2018. All cases underwent clinical, laboratory, histopathological and electroneuromyographic evaluations.

RESULTS

Of 104 biopsied patients, leprosy was confirmed in 89.4% (93/104). The biopsied nerves were the ulnar (67.8% [63/93]), superficial fibular (21.5% [20/93]), sural (8.6% [8/93]), radial (1.1% [1/93]) and deep fibular (1.1% [1/93]). Twenty-nine percent (27/93) presented histopathological abnormalities and 4.4% (4/93) presented acid-fast bacilli. Nerve and superjacent skin quantitative polymerase chain reaction were positive in 49.5% (46/93) and 24.8% (23/93) of cases, respectively. Patients with multiple mononeuropathy had a higher frequency of histopathological abnormalities (p=0.0077).

CONCLUSIONS

This study reinforces peripheral nerve biopsy's role as an important tool in the investigation of primary neural cases, contributing to the early diagnosis and also reducing diagnostic errors and the need for empirical treatment.

Biotechnological and Immunological Platforms Based on PGL-I Carbohydrate-Like Peptide of Mycobacterium leprae for Antibodies Detection Among Leprosy Clinical Forms

Phenolic glycolipid I (PGL-I) is an abundant antigen on the Mycobacterium leprae cell wall, commonly used for operational classification of leprosy patients. Our aim was to develop PGL-I mimotopes with similar characteristics and functions of the native antigen. We have used a random peptide phage display (PD) library for selections against the monoclonal antibody anti-PGL-I. After three selection cycles, six peptides were identified. All sequences were interspersed by a spacer generating a chimeric peptide (PGLI-M3) that was artificially synthesized. The highly reactive peptide was submitted to a reverse PD selection with a single-chain Fv (scFv) antibody fragment combinatorial library. The most reactive scFv was then validated by enzyme-linked immunosorbent assay (ELISA) against both native PGL-I and two derived synthetic (NDO and ND-O-HSA). We have further proved the scFv specificity by detecting M. leprae bacilli in leprosy lesions through immunohistochemistry. We then described its applicability in ELISA for all clinical forms and household contacts (HC). Afterward, we showed differential binding affinities of PGLI-M3 to sera (anti-PGL-I IgM) from all leprosy clinical forms through surface plasmon resonance (SPR). ELISA IgM detection showed 89.1% sensitivity and 100% specificity, considering all clinical forms. Positivity for anti-PGL-I IgM was twofold higher in both HC and patients with paucibacillary forms in hyperendemic regions than in endemic ones. The SPR immunosensor was able to differentiate clinical forms with 100% accuracy. This is the first time that a PGL-I mimotope has efficiently mimicked the carbohydrate group of the M. leprae antigen with successful immunoassay applications and may become a substitute for the native antigen.

Evaluation of the cutaneous sensation of the face in patients with different clinical forms of leprosy

Background

Leprosy can be considered to be the most common peripheral neuropathy of infectious etiology and constitutes a public health problem. The standard routine examination for assessing sensory impairment in leprosy neuropathy basically evaluates hands, feet and eyes. However, evaluation of facial cutaneous sensation is not routinely performed.

Objectives

The aim of this study was to evaluate facial cutaneous sensation in patients with different clinical forms of leprosy and compare the findings with those from healthy individuals.

Methodology

19 healthy controls and 71 leprosy patients who were being treated at a national reference center for leprosy in Brazil underwent facial sensation assessment using the Semmes-Weinstein monofilament test. This test was applied over the facial areas corresponding to the ophthalmic, maxillary and mandibular distal branches of the trigeminal nerve.

Results

The predominant clinical form in terms of changes to facial cutaneous sensation was lepromatous leprosy (LL), followed by the borderline-borderline (BB), and borderline-lepromatous (BL) forms, in comparison with healthy individuals. The distal branches most affected were the zygomatic (28.2%; 20/71), buccal (23.9%; 17/71) and nasal (22.5%; 16/71). There was asymmetrical sensory impairment of the face in 62.5% (20/32) of the cases.

Conclusion

The face is just as impaired in leprosy as are the feet, hands and eyes, but facial impairment is underdiagnosed. Our evaluation on the different sensory branches and evidence of asymmetrical impairment of the face confirm the classically described pattern of leprosy neuropathy, i.e. consisting of asymmetrical and predominantly sensory peripheral neuropathy.

Anti-Lipoarabinomannan-Specific Salivary IgA as Prognostic Marker for Leprosy Reactions in Patients and Cellular Immunity in Contacts

Leprosy causes the most common peripheral neuropathy of infectious etiology, posing an important public health problem worldwide. Understanding the molecular and immunological mechanisms of nerve damage induced by M. leprae is mandatory to develop tools for early diagnosis and preventive measures. The phenolic glycolipid 1 (PGL-1) and lipoarabinomannan (LAM) antigens are major components of the bacterial surface and are implicated on leprosy immunopathogenesis and neural damage. Although the anti-PGL-1 serum IgM is highly used for operational classification of patients, the anti-LAM salivary IgA (sIgA) has not been investigated as diagnostic or prognostic marker in leprosy. Our aim was to assess the presence of anti-LAM sIgA in leprosy patients and their contacts in order to demonstrate whether such expression was associated with leprosy reactions. Distinct patterns of anti-LAM slgA were observed among groups, which were stratified into treatment-naïve patients (116), patients who completed multidrug therapy—MDT (39), household contacts (111), and endemic controls (11). Both anti-LAM sIgA and anti-PGL-I serum IgM presented similar prognostic odds toward leprosy reactions [(odds ratio) OR = 2.33 and 2.78, respectively]. Furthermore, the anti-LAM sIgA was highly correlated with multibacillary (MB) forms (OR = 4.15). Contrarily, among contacts the positive anti-LAM sIgA was highly correlated with those with positive Mitsuda test, suggesting that the presence of anti-LAM slgA may act as an indicator of cellular immunity conferred to contacts. Our data suggest that anti-LAM slgA may be used as a tool to monitor patients undergoing treatment to predict reactional episodes and may also be used in contacts to evaluate their cellular immunity without the need of Mitsuda tests.

Molecular, immunological and neurophysiological evaluations for early diagnosis of neural impairment in seropositive leprosy household contacts

Background

Household contacts constitute the highest risk group for leprosy development, and despite significant progress in the disease control, early diagnosis remains the primary goals for leprosy management programs.

Methods

We have recruited 175 seropositive and 35 seronegative household contacts from 2014 to 2016, who were subjected to an extensive protocol that included clinical, molecular (peripheral blood qPCR, slit-skin smear qPCR, skin biopsy qPCR) and electroneuromyographic evaluations.

Results/Principal findings

The positivity of peripheral blood qPCR of seropositive contacts was 40.6% (71/175) whereas only 8.6% (3/35) were qPCR positive in seronegative contacts (p = 0.0003). For the slit-skin smear, only 4% (7/175) of seropositive contacts presented positive bacilloscopy, whereas the qPCR detected 47.4% (83/175) positivity in this group compared with only 17.1% (6/35) in seronegative contacts (p = 0.0009). In the ENMG evaluation of contacts, 31.4% (55/175) of seropositives presented some neural impairment, and 13.3% (4/35) in seronegatives (p = 0.0163). The presence of neural thickening conferred a 2.94-fold higher chance of ENMG abnormality (p = 0.0031). Seropositive contacts presented a 4.04-fold higher chance of neural impairment (p = 0.0206). The peripheral blood qPCR positivity presented odds 2.08-fold higher towards neural impairment (OR, 2.08; p = 0.028). Contrarily, the presence of at least one BCG vaccine scar demonstrated 2.44-fold greater protection against neural impairment (OR = 0.41; p = 0.044).

Conclusions/Significance

ELISA anti-PGL-I is the most important test in determining the increased chance of neural impairment in asymptomatic leprosy household contacts. The combination of the two assays (ELISA anti-PGL-I and peripheral blood qPCR) and the presence of BCG scar may identify individuals with higher chances of developing leprosy neuropathy, corroborating with the early diagnosis and treatment.

Despite the apparent progress observed in recent years in leprosy control, early identification of cases remains one of the primary objectives of control programs. In addition, the failure of the current therapeutic scheme on the incidence of leprosy demonstrates that the disease elimination as a public health program promoted by the World Health Organization (WHO) depends on an incisive action to interrupt its transmission chain. The long incubation period of leprosy, its insidious symptoms and signs may difficult its diagnosis. Several studies have recently demonstrated that IgM anti-PGL-I seropositive contacts present higher chances to become ill than seronegative ones. Therefore, our question was: do seropositive contacts at greater risk of becoming sick already present subclinical neural damage? Therefore, our approach was to analyse anti-PGL-I seropositive contacts through electroneuromyography. The development and implementation of more specific and sensitive methods for the detection of M. leprae and its neural impairment, using immunological, molecular and neurophysiological tools are mandatory to increase the knowledge of leprosy epidemiology, to break its chain of transmission, thereby enabling effective control of this disease. This report demonstrated that seropositive contacts is the population group with higher chances of neural impairment.

Revisiting primary neural leprosy: Clinical, serological, molecular, and neurophysiological aspects

BACKGROUND

Leprosy neuropathy is considered the most common peripheral neuropathy of infectious etiology worldwide, representing a public health problem. Clinical diagnosis of primary neural leprosy (PNL) is challenging, since no skin lesions are found and the slit skin smear bacilloscopy is negative. However, there are still controversial concepts regarding the primary-neural versus pure-neural leprosy definition, which will be explored by using multiple clinical-laboratory analyses in this study.

METHODOLOGY/PRINCIPAL FINDINGS

Seventy patients diagnosed with primary neural leprosy from 2014 to 2016 underwent clinical, laboratorial and neurophysiological evaluation. All patients presented an asymmetric neural impairment, with nerve thickening in 58.6%. Electroneuromyography showed a pattern of mononeuropathy in 51.4%. Positivity for ELISA anti-PGL1 was 52.9%, while the qPCR of slit skin smear was 78.6%. The qPCR of nerve biopsies was positive in 60.8%. Patients with multiple mononeuropathy patterns showed lower levels of anti-PGL-1 (p = 0.0006), and higher frequency of neural thickening (p = 0.0008) and sensory symptoms (p = 0.01) than those with mononeuropathy.

CONCLUSIONS/SIGNIFICANCE

PNL is not a synonym of pure neural leprosy, as this condition may include a generalized immune response and also a skin involvement, documented by molecular findings. Immunological, molecular, and neurophysiological tools must be implemented for diagnosing primary neural leprosy to achieve effective treatment and reduction of its resultant disabilities that still represent a public health problem in several developing nations. Finally, we propose a algorithm and recommendations for the diagnosis of primary neural leprosy based on the combination of the three clinical-laboratorial tools.

Number of leprosy reactions during treatment: clinical correlations and laboratory diagnosis

INTRODUCTION:

The occurrence of leprosy reactions, a common event during treatment, may be mostly related to the action of multidrug therapy on Mycobacterium leprae. The clinical and laboratory monitoring of patients with reactions is important, since collecting data that assists in predicting the risk of reactions may help to prevent disability.

METHODS:

This was a sectional study, in order to correlate clinical and laboratory diagnosis with the number of reactions during treatment. Spearman's correlation was used to verify the degree of association between the assessed variables.

RESULTS:

This study was conducted with 211 patients with leprosy reactions during treatment of M. leprae. The borderline tuberculoid group was the most prevalent clinical form (74/211; 35.1%) and the type one reaction showed the highest frequency (136/211; 64.5%). It was observed that 73.5% (155/211) of reactions occurred within 3 months of the initiation of multidrug therapy. The diagnostic values, including the bacterial indices (BIs) of dermal smears (r = 0.21, p < 0.05) and skin biopsies (r = 0.20; p < 0.05), showed a positive correlation with the number of reactions during treatment.

CONCLUSIONS:

This research showed a positive correlation between bacillary load markers and the number of leprosy reactions. This study provided scientific support to future research aiming to elucidate the influence of antigenic load on the number of leprosy reactions during treatment.

Neural complications and physical disabilities in leprosy in a capital of northeastern Brazil with high endemicity

INTRODUCTION

Leprosy is an infectious disease whose etiologic agent is Mycobacterium leprae, manifested by dermatological and neurological signs and symptoms.

OBJECTIVE

To investigate neural changes and the degree of physical disability in the eyes, hands and feet before and after treatment, as well as sociodemographic and clinical profile of patients affected by leprosy.

METHOD

A longitudinal epidemiological study comprising 155 patients with leprosy, from a spontaneous demand, diagnosed between March 2010 and February 2011, and treated with multidrug therapy (MDT) between March 2010 and July 2012 in a program for leprosy eradication in São Luis (MA), Brazil.

RESULTS

Before treatment, 46.5% of patients were considered as borderline, 51.6% had some alteration in the eyes and 52.3% in the feet, and the radial nerve (18.7%) was the most affected. There was a statistically significant difference between the changes in the radial nerve at the beginning of and after treatment.

CONCLUSIONS

The analysis points to late diagnosis, as some patients have had abnormal neural and physical disabilities before treatment.

Molecular Evidence for the Aerial Route of Infection of Mycobacterium leprae and the Role of Asymptomatic Carriers in the Persistence of Leprosy

BACKGROUND

 Leprosy persists as a public health problem. The chain of transmission and mechanism of infection are not completely understood. In the current study, we investigated the route of infection and of disease onset, from airway exposure, colonization, and bloodstream dissemination.

METHODS

 Mycobacterium leprae DNA was detected through quantitative polymerase chain reaction in nasal vestibule, nasal turbinate mucosa, and peripheral blood samples, along with anti-phenolic glycolipid I serology and skin tests from the same individual, from 113 leprosy patients and 104 household contacts of patients (HHCs). Bivariate statistics and multiple correspondence analysis were employed.

RESULTS

 The rates of DNA positivity among patients were 66.4% (75 of 113) for nasal swab samples, 71.7% (81 of 113) for nasal turbinate biopsy samples, 19.5% (22 of 113) for blood samples, with seropositivity of 62.8% (71 of 113 samples) and with increasing incidences toward the multibacillary pole of the clinical spectrum. Positivity among HHCs were as follows: 49% (51 of 104) for nasal swab samples, 53.8% (56 of 104) for nasal biopsy samples, 6.7% (7 of 104) for blood samples, and 18.3% (19 of 104 samples) for anti-phenolic glycolipid I serology. During the follow-up of 5-7 years, out of 104 HHCs, 7 developed leprosy (6.7%). Risk for the disease outcome was estimated by comparing results in HHCs who develop leprosy with those not affected. Neither nasal passage nor mucosa positivity was determinant of later disease onset; however, blood presence increased the risk for disease development (relative risk/positive likelihood ratio, 5.54; 95% confidence interval, 1.30-23.62), as did seropositivity (positive likelihood ratio, 3.69 [1.67-8.16]; relative risk, 5.97 [1.45-24.5]).

CONCLUSIONS

 Our findings strongly suggest that the aerosol route of infection and transmission is predominant and that HHCs contribute to the infection risk to themselves and probably to others.

Risk-benefit assessment of Bacillus Calmette-Guérin vaccination, anti-phenolic glycolipid I serology, and Mitsuda test response: 10-year follow-up of household contacts of leprosy patients

INTRODUCTION

Despite multidrug therapy, leprosy remains a public health issue. The intradermal Bacillus Calmette-Guérin (BCG) vaccine, Mitsuda test (lepromin skin test), and anti-phenolic glycolipid I (PGL-I) serology are widely used in leprosy studies and have shown great epidemiological value.

METHODS

This longitudinal study evaluated the relative risks and benefits of these three tools by comparing results observed in household contacts (HHCs) of leprosy patients who developed leprosy with those of HHCs who did not in a population of 2,992 individuals monitored during a 10-year period.

RESULTS

Seventy-five (2.5%) new leprosy cases were diagnosed, including 28 (0.9%) co-prevalent cases. Therefore, for the risk-benefit assessment, 47 (1.6%) HHCs were considered as truly diagnosed during follow-up. The comparison between healthy and affected contacts demonstrated that not only did BCG vaccination increase protection, but boosters also increased to 95% relative risk (RR) reduction when results for having two or more scars were compared with having no scars [RR, 0.0459; 95% confidence interval (CI), 0.006-0.338]. Similarly, Mitsuda reactions >7mm in induration presented 7-fold greater protection against disease development compared to reactions of 0-3mm (RR, 0.1446; 95% CI, 0.0566-0.3696). In contrast, anti-PGL-I ELISA seropositivity indicated a 5-fold RR increase for disease outcome (RR, 5.688; 95% CI, 3.2412-9.9824). The combined effect of no BCG scars, Mitsuda reaction of <7mm, and seropositivity to anti-PGL-I increased the risk for leprosy onset 8-fold (RR, 8.109; 95% CI, 5.1167-12.8511).

CONCLUSIONS

The adoption of these combined assays may impose measures for leprosy control strategies.

Application of the SRQ20 and the protocol of psychological assessment in patients with leprosy in a Reference Centre in Brazil

This study aims to apply the protocol of psychological assessment (PAP) and the SRQ-20 to analyse the psychological profile of 130 leprosy patients, in order to evaluate the incidence of Common Mental Disorders (CMD), and screen patients with higher risk of psychological distress. The following results were found in the PAP: 31.53%, 23.8% and 16.9% reported an unsatisfactory childhood, adolescence and adulthood, respectively; 31.53% are afraid of being discriminated against and 16.9% experienced discrimination. Also, 13.07% reported drastic life changes due to leprosy; 29.23% have low self-esteem, 31.53% have real fear and 22.3% have phantasmal fear. In the SRQ-20, the prevalence of CMDs was 32.3%, with the majority being female, married, with low education (primary education), low self-esteem, and with a drastic change in life. Conclusion: This is one of the few studies on the psychological profile of leprosy patients demonstrating the importance of the application of investigative technologies in psychopathological screening, aiming on adherence to treatment and psychotherapy planning. Furthermore, it provides support for reflection on the integrality of healthcare for leprosy patients and the importance of psychologists in health teams.

Antigen-specific assessment of the immunological status of various groups in a leprosy endemic region

BACKGROUND

Serological tests can be important tools to assist in the diagnosis of leprosy and can contribute to an earlier diagnosis. The aim of this study was to evaluate the antibody responses against phenolic glycolipid-1 (PGL-1), natural disaccharide linked to human serum albumin via an octyl (NDO-HSA), Leprosy IDRI Diagnostic-1 (LID-1) and natural disaccharide octyl--Leprosy IDRI Diagnostic-1 (NDO-LID) in leprosy patients, household contacts of patients and the general population.

METHODS

Enzyme-linked immunosorbent assays were used to analyze the antigen-specific antibody responses of 94 leprosy cases, 104 household contacts of cases and 2.494 individuals from the general population.

RESULTS

A positive correlation was observed for the antibody responses to all antigens studied. A higher proportion of seropositivity for all antigens, along with stronger magnitude of response, was observed in multibacillary (MB) leprosy patients and household contacts of MB leprosy patients compared with the levels observed in paucibacillary (PB) leprosy patients and household contacts of PB leprosy patients. A substantial and significant positive correlation was found between seropositivity and the bacterial index for the leprosy patients. Anti-PGL-1 tests were more frequently positive than anti-NDO-HSA tests among patients with all clinical forms of leprosy and among the group of household contacts. The LID-1 and NDO-LID antigens showed a greater capacity to identify household contacts and individuals from the general population infected with M. leprae.

CONCLUSIONS

Tests that measure the antibody responses against LID-1, NDO-LID, NDO-HSA and PGL-1 were effective tools for the detection of patients with MB leprosy. Our data indicate that the anti-LID-1 and anti-NDO-LID responses were more effective than an anti-NDO-HSA response for the identification of individuals with subclinical infection.

Factors associated with neural alterations and physical disabilities in patients with leprosy in São Luis, State of Maranhão, Brazil

INTRODUCTION

Leprosy is a chronic infectious disease that is caused by Mycobacterium leprae. The objective of this study was to evaluate the risk factors that are associated with neural alterations and physical disabilities in leprosy patients at the time of diagnosis.

METHODS

A prospective cross-sectional study was conducted on 155 leprosy patients who participated in a program that aimed to eliminate leprosy from São Luis, State of Maranhão.

RESULTS

Patients who were 31-45 years of age, were older than 60 years of age or had a partner were more likely to have a disability. Patients with partners were 1.14 times more likely (p = 0.025) to have disabilities of the hands. The frequency of disabilities in the feet among the patients with different clinical forms of leprosy was statistically significant.

CONCLUSIONS

The identification of risk factors that are associated with neural alterations and physical disabilities in leprosy patients is important for diagnosing the disease because this approach enables physicians to plan and prioritize actions for the treatment and monitoring of patients.

Unveiling healthy carriers and subclinical infections among household contacts of leprosy patients who play potential roles in the disease chain of transmission

Leprosy transmission still occurs despite the availability of highly effective treatment. The next step towards successfully eliminating leprosy is interrupting the chain of transmission of the aetiological agent, Mycobacterium leprae. In this investigation, we provide evidence that household contacts (HHCs) of leprosy patients might not only have subclinical infections, but may also be actively involved in bacilli transmission. We studied 444 patients and 1,352 contacts using anti-phenolic glycolipid-I (PGL-I) serology and quantitative polymerase chain reaction (qPCR) to test for M. leprae DNA in nasal swabs. We classified the patients according to the clinical form of their disease and the contacts according to the characteristics of their index case. Overall, 63.3% and 34.2% of patients tested positive by ELISA and PCR, respectively. For HHCs, 13.3% had a positive ELISA test result and 4.7% had a positive PCR test result. The presence of circulating anti-PGL-I among healthy contacts (with or without a positive PCR test result from nasal swabs) was considered to indicate a subclinical infection. DNA detected in nasal swabs also indicates the presence of bacilli at the site of transmission and bacterial entrance. We suggest that the concomitant use of both assays may allow us to detect subclinical infection in HHCs and to identify possible bacilli carriers who may transmit and disseminate disease in endemic regions. Chemoprophylaxis of these contacts is suggested.

Identification of clinical, epidemiological and laboratory risk factors for leprosy reactions during and after multidrug therapy

This cross-sectional retrospective study evaluated 440 leprosy patients; 57% (251/440) had leprosy reactions during and/or after multidrug therapy, 80.5% (202/251) of whom presented with multibacillary leprosy. At diagnosis, positive bacterial index (BI) [odds ratio (OR) = 6.39; 95% confidence interval (CI): 4.1-10.1)] or polymerase chain reaction (PCR) (OR = 9.15; 95% CI: 5.4-15.5) in skin smears, anti-phenolic glycolipid-1 (anti-PGL-1) ELISA (OR = 4.77; 95% CI: 2.9-7.9), leucocytosis (OR = 9.97; 95% CI: 3.9-25.7), thrombocytopenia (OR = 5.72; 95% CI: 2.3-14.0) and elevated lactate dehydrogenase (OR = 2.38; 95% CI: 1.4-4.0) were potential markers for the development of reactions during treatment. After treatment, positive BI (OR = 8.47; 95% CI: 4.7-15.3) and PCR (OR = 6.46; 95% CI: 3.4-12.3) in skin smears, anti-PGL-1 ELISA (OR = 2.25; 95% CI: 1.3-3.9), anaemia (OR = 2.36; 95% CI: 1.2-4.5), leucocytosis (OR = 4.14; 95% CI: 1.5-11.6) and thrombocytopenia (OR = 3.70; 95% CI: 1.3-2.2) were risk factors for the occurrence of reactions during the study period. The identification of groups with an increased risk for developing reactions will allow for the timely development of a treatment plan to prevent nerve damage and, therefore, the appearance of the disabling sequelae associated with the stigma of leprosy.

Mycobacterium leprae DNA in peripheral blood may indicate a bacilli migration route and high-risk for leprosy onset

Leprosy epidemiological studies have been restricted to Mycobacterium leprae DNA detection in nasal and oral mucosa samples with scarce literature on peripheral blood. We present the largest study applying quantitative real-time PCR (qPCR) for the detection of M. leprae DNA in peripheral blood samples of 200 untreated leprosy patients and 826 household contacts, with results associated with clinical and laboratory parameters. To detect M. leprae DNA a TaqMan qPCR assay targeting the M. leprae ML0024 genomic region was performed. The ML0024 qPCR in blood samples detected the presence of bacillus DNA in 22.0% (44/200) of the leprosy patients: 23.2% (16/69) in paucibacillary (PB), and 21.4% (28/131) in multibacillary (MB) patients. Overall positivity among contacts was 1.2% (10/826), with similar percentages regardless of whether the index case was PB or MB. After a follow-up period of 7 years, 26 contacts have developed leprosy. Comparing the results of healthy contacts with those that become ill, ML0024 qPCR positivity at the time of diagnosis of their index case represented an impressive 14.78-fold greater risk for leprosy onset (95% CI 3.6-60.8; p <0.0001). In brief, contacts with positive PCR in blood at diagnosis of index cases are at higher risk of later leprosy onset and this marker might be combined with other prognostic markers for management of contacts, which requires further studies.

Bacterial load in the nose and its correlation to the immune response in leprosy patients

INTRODUCTION

Leprosy, whose etiologic agent is M. leprae, has its clinical manifestations correlated with distinct immunologic forms. The mechanism of infectivity and dissemination of the disease are not completely known, although the nasal mucosa is supposed to have an important role in pathogenesis.

OBJECTIVE

To correlate the clinical and bacteriological parameters with that of nasal biopsy and immunological tests, such as lepromin and ML-Flow results, in untreated leprosy patients.

MATERIAL AND METHOD

Two hundred and twenty-two patients were evaluated, clinically classified and subjected to skin smear, nasal biopsy, ML-Flow, and Mitsuda test.

RESULTS

689% of the cases were borderline cases. Nasal biopsy revealed 91.4% positivity in those who had specific antibodies against M. leprae on blood sample. Lepromatous leprosy cases were 100% positive on ML-flow test, had a large involvement in the nasal mucosa (91%), positive skin smears (100%) and negative Mitsuda test. Nasal bacillary index showed a good correlation with ML-Flow and had similar results when compared to skin smear. The tests agreement was good, revealing that nasal biopsy can be reliable in the diagnosis of multibacillary clinical forms and in the evaluation of the immunological status of leprosy patients.

CONCLUSION

The presence of disseminated bacilli in the nasal mucosa was similar to skin involvement, when correlated with Mitsuda test and ML-Flow. As a result, the role of nasal bacillary index may play an important role in the clinical and immunologic characterization of leprosy patients.

Comparison of three immunological tests for leprosy diagnosis and detection of subclinical infection

OBJECTIVE

Our aim was to compare the performance of three serological assays in leprosy patients and their household contacts utilising two quantitative ELISA tests using native PGL-I (PGL-1 ELISA), synthetic ND-O-HSA (ND-O-HSA ELISA), and the semi-quantitative lateral flow test (ML Flow).

METHODS

Comparisons among three immunological assays, PGL-I ELISA, ND-O-HSA ELISA, and ML Flow were performed in 154 leprosy patients, 191 household contacts and 52 health subjects.

RESULTS

The sensitivity results of the PGL-1, ND-O-HSA, and ML Flow were 68.83%, 63.84%, and 60.65%, respectively, with specificity of 98% for both ELISA assays. The native and synthetic PGL-I ELISA assays detected antibodies in 22.73% and 31.82% of the paucibacillary (PB) patients, respectively and the ML Flow test did not detect antibodies in this group. The ML Flow test was able to discriminate patients into PB or multibacillary (MB) forms, while the native PGL-I and ND-O-HSA was correlated with the bacillary load and the Ridley-Jopling clinical forms. In household contacts, the native PGL-I, ND-O-HSA, and ML Flow assays detected seropositivity of 25%, 17%, and 10%, respectively.

CONCLUSIONS

The use of ELISA and ML Flow tests are thus recommended as additional tools in the diagnosis and classification of the clinical forms, aiding in prescribing the correct treatment regimen to prevent subsequent nerve damage and disability, and besides, the PGL-I ELISA may be used to detect subclinical infection in leprosy.

Specific IgG antibody responses may be used to monitor leprosy treatment efficacy and as recurrence prognostic markers

Although curable, leprosy requires better diagnostic and prognostic tools to accompany therapeutic strategies. We evaluated the serum samples of leprosy patients from Venezuela and Brazil for reactivity against the specific recombinant proteins, ML0405 and ML2331, and the LID-1 fusion protein that incorporates both of these antigens. Antigen-specific IgG was highest in lepromatous leprosy patients (LL) and decreased across the disease spectrum, such that only a small subset of true tuberculoid patients (TT) tested positive. The impact of multidrug therapy (MDT) on these antibody responses was also examined. Several years after treatment, the vast majority of Venezuelan patients did not possess circulating anti-LID-1, anti-ML0405, and anti-ML2331 IgG, and the seropositivity of the remaining cases could be attributed to irregular treatment. At discharge, the magnitude and proportion of positive responses of Brazilian patients against the proteins and phenolic glycolipid (PGL)-I were lower for most of the clinical forms. The monthly examination of IgG levels in LL patient sera after MDT initiation indicated that these responses are significantly reduced during treatment. Thus, responses against these antigens positively correlate with bacillary load, clinical forms, and operational classification at diagnosis. Our data indicate that these responses could be employed as an auxiliary tool for the assessment of treatment efficacy and disease relapse.

Evaluation of the agreement between clinical and laboratorial exams in the diagnosis of leprosy

This study examined the correlation between the clinical and laboratory diagnosis of leprosy, using biopsy results from laboratories 'A' and 'B' and the ML Flow test. Clinical and histopathological diagnoses presented 67.6% agreement. The laboratories showed 73.7% agreement in the bacterial index and laboratory 'B' detected 25.4% more positives. The highest agreement was in the LL form and lowest, in the I form. The highest diagnostic discrepancy was for the BB form. Clinical diagnosis agreement was 41.3% for laboratory 'A' and 54% for 'B'. The ML Flow test reclassified 10.7% of the patients. The spectrum of leprosy classification is important for a clearer understanding of the disease and its proper treatment, but is not used in health services, which use the simplified WHO criteria. This could be complemented by ML Flow testing. Such simplification is unacceptable for Leprosy Reference Centers regarding patient attendance, teaching and research, for which the standardization of the Ridley-Jopling classification is recommended.

Contribution of nasal biopsy to leprosy diagnosis

BACKGROUND

The nasal mucosa plays the main role as the entry and the exit of leprosy bacilli and the nasal involvement may precede the skin lesions by several years. Nasal biopsy has been used in research but its clinical application has not been described. We evaluated the contribution of the nasal biopsy for the diagnosis of leprosy and its correlation to skin biopsy and skin smear in untreated patients.

METHODS

We evaluated changes in nasal biopsy in 227 leprosy patients. Patients were clinically classified and skin and nasal biopsies and skin smear were performed.

RESULTS

Nasal biopsy showed positivity in 100% of the lepromatous spectrum decreasing toward the tuberculoid (TT) pole. Patients with TT or indeterminate forms did not present any nasal alterations, showing that they are the true paucibacillary forms. Also, the nasal biopsies of two patients were the only exam to show positivity. The bacillary index of the nasal biopsy was strongly correlated to skin biopsy and slit-skin smear. Additionally, the agreement among the exams was good, revealing the reliability of the nasal biopsy in leprosy diagnosis.

CONCLUSION

The present study showed a rate of 48% of positivity in nasal biopsy of untreated patients, correlating well with skin biopsy and skin smear. Thus, the method in leprosy diagnosis and clinical form classification has shown great reliability.

Leprosy pathogenetic background: a review and lessons from other mycobacterial diseases

Leprosy is a disease caused by Mycobacterium leprae that initially affects the peripheral nervous system with patients exhibiting contrasting clinical, immunological, and pathological manifestations despite minimal genetic variation among bacilli isolates. Its clinical manifestations are related to M. leprae survival, innate and acquired immune responses, and interactions between host and bacterial proteins, preventing their invasion and infection, or promoting their development and pathogenesis. The complex molecular interactions in affected individuals influenced by the pathogenetic background will be explored in this review. However, the great genetic diversity imposes difficulty for understanding disease development, and it is likely that many factors and metabolic pathways regulating the immense and contrasting symptomatology will yet be revealed. Four pathways may play a central role in leprosy, including the TLR/LIR-7, VDR, TNF-alpha, and TGF-beta1 for which a large amount of gene polymorphisms have been described that could potentially affect the clinical outcome. Cross-talk pathways may significantly change the course of the disease, depending on the specific disequilibrium of genic homeostasis, which is highly dependent on the environment, antigens that are presented to the host cell, and specific polymorphisms that interact with other genes, external factors, and pathogen survival, culminating in leprosy occurrence. Currently, the microarray-based genomic survey of gene polymorphisms, multiple gene expression analyses, and proteomic technologies, such as mass spectrometry and phage display applied in the discovery of antigens, represent a great potential for evaluating individual responses of leprosy patients and contacts to predict the outcome and progression of the disease. At present, none of the genes is good prognostic marker; however, in the near future we may use multiple targets to predict infection and leprosy development.

Detection of Mycobacterium leprae DNA in skin lesions of leprosy patients by PCR may be affected by amplicon size

Despite the high sensitivity and specificity of PCR for infectious disease diagnostics, it has presented low sensitivity for Mycobacterium leprae DNA detection in the tuberculoid pole (TT and BT) of leprosy. In order to demonstrate the effect of amplicon size on the efficacy of PCR detection of M. leprae DNA in skin lesions of leprosy patients, two pairs of primers targeting the M. leprae genomic DNA, RLEP3 (X17153), were used to amplify fragments of 372 and 130-bp until their PCR end-points were reached after 40 reaction cycles. Skin biopsies of leprosy lesions in 110 non-treated patients were used for bacilloscopy index (BI) analysis and PCR tests. The 130-bp fragment was detected in 73.6% of samples (81/110), and classified as TT (40%), BT (55.5%), and 100% of BB, BL and LL. The 372-bp fragment was detected in 52.7% and classified as TT (13.3%), BT (33.3%), BB (64.7%), BL (83.3%), and LL (95.2%). The BI of biopsies was positive in 39.1% of samples, classified as TT (0%), BT (2.2%), BB (64.7%), BL (91.6%), and LL (95.2%). The shorter amplicon (130-bp) has improved diagnosis by 20.9 and 34.5% in relation to the 372-bp fragment and the BI, respectively, and has shown a superior sensitivity (73.6%), specificity (100%) and accuracy (86.2%). The 130-bp amplicon could not detect % of positive BI of biopsies in BT cases. Therefore, for confirmatory diagnosis, we propose the use of PCR detection of the 130-bp genomic target, especially when the tuberculoid pole forms are considered, which has reached 51.6% of positivity in this group.

Interaction of TaqI polymorphism at exon 9 of the vitamin D receptor gene with the negative lepromin response may favor the occurrence of leprosy

Controversies over the vitamin D receptor (VDR) acting as a susceptibility factor in Mycobacterium sp. infections may be the result of incorrect population stratification. The risk of leprosy occurrence conditioned by VDR polymorphism was investigated by stratifying the population of a highly endemic Brazilian region into negative and positive Mitsuda responses. Leprosy patients (102) and a group of healthy nonconsanguineous household contacts (68) were genotyped for the VDR TaqI polymorphism (T/t). TT and Tt genotypes were not considered to be risk factors as their odds ratios (OR) were not different from those presented by the negative Mitsuda response individuals. The combination of the tt genotype and the negative Mitsuda test provided an occurrence rate 13 times higher in leprosy patients than in controls with positive Mitsuda responses. This suggests that there is a higher risk of leprosy development when individuals carry this unfavorable combination, and demonstrates a possible synergistic role of these two variables in leprosy susceptibility via effects on cellular immunity.

Detection of Mycobacterium leprae in nasal mucosa biopsies by the polymerase chain reaction

Several discoveries about leprosy indicate that Mycobacterium leprae transmission mainly occurs by inhalation, and the nose is major port of entry and exit. The present study evaluated the clinical application of PCR for detection of M. leprae DNA in nasal mucosa biopsies in untreated leprosy patients (52) and their contacts (99) from the State Reference Center in Sanitary Dermatology and Leprosy, Uberlandia, MG, Brazil. PCR detection of a 372-base pair DNA fragment from M. leprae was accomplished in 36 (69.2%) patients, from which 34 (91.9%) of them were multibacillaries. Furthermore, PCR was positive in 3 (16.7%) of 18 slit-skin smear negative, 4 (25.0%) of 16 skin lesion BI negative, 8 (33.3%) of 24 nasal mucosa BI negative patients, and 10 of 99 contacts (10.1%). The presence of bacilli in 10.1% of the contacts may potentially reflect an occult leprosy, and these patients must be accompanied, followed by a chemoprophylaxy treatment. Considering all PCR results against clinical and BI classification of patients and controls, we have found a sensitivity of 69.2%, a specificity of 89.9%, and an accuracy of 82.8%. It has been demonstrated here through PCR of nasal biopsies that the bacillus invades the mucosa, passing through the nasal inferior turbinate to reach peripheral blood. Therefore, the molecular investigation of invasive nasal biopsies by PCR tests has proven to be useful in defining patients of higher risk of transmission and risk-group contacts, which is an important step to reach the World Health Organization objective towards the elimination of leprosy as a public health problem.

Susceptibility to leprosy may be conditioned by an interaction between the NRAMP1 promoter polymorphisms and the lepromin response

Controversial results have been achieved by attempting to associate the NRAMP1 gene with Mycobacterium leprae susceptibility as well as with the Mitsuda reaction, which represents a specific immune response to M. leprae. This study evaluated this association as well as the interaction of the polymorphism (GT)(n) in the promoter region of the NRAMP1 gene with a specific immune response to M. leprae measured by the intradermal Mitsuda test in leprosy patients and in non-consanguineous household contacts. The study aimed to evaluate the association of this gene polymorphism with resistance or susceptibility to the disease, and/or with clinical forms of the disease, in a population in an endemic area served by the State Reference Center in Sanitary Dermatology and Leprosy, Federal University of Uberlandia, MG, Brazil. Leprosy patients (90) were diagnosed according to Ridley and Jopling criteria and they grouped into multibacillary (MB) and paucibacillary (PB) patients. The control group consisted of 61 non-consanguineous contacts. NRAMP1 promoter genotypes were obtained through amplification by the polymerase chain reaction (PCR) followed by the detection through the low ionic-strength single strand conformational polymorphism (LIS-SSCP) electrophoretic technique. There were no significant differences in the allelic and genotypic frequencies for alleles 2, 3, and 4 in relation to the Mitsuda test among patients and household contacts, nor between those with MB and PB forms. However, individuals with a negative lepromin response associated with genotypes 22 and 23 presented a 7- and 8-fold greater chance of developing leprosy, respectively. Therefore, the NRAMP1 gene promoter polymorphism exhibited an interaction with the lepromin response, suggesting that allele 2 of the NRAMP1 promoter is an independent genetic factor that predisposes cells to enable pathogen survival, probably due to its low efficiency in iron transport. However, establishment of the infection and disease development may be conditioned by other immunological and genetic factors.

Susceptibility to leprosy may be conditioned by an interaction between the NRAMP1 promoter polymorphisms and the lepromin response

Controversial results have been achieved by attempting to associate the NRAMP1 gene with Mycobacterium leprae susceptibility as well as with the Mitsuda reaction, which represents a specific immune response to M. leprae. This study evaluated this association as well as the interaction of the polymorphism (GT)(n) in the promoter region of the NRAMP1 gene with a specific immune response to M. leprae measured by the intradermal Mitsuda test in leprosy patients and in non-consanguineous household contacts. The study aimed to evaluate the association of this gene polymorphism with resistance or susceptibility to the disease, and/or with clinical forms of the disease, in a population in an endemic area served by the State Reference Center in Sanitary Dermatology and Leprosy, Federal University of Uberlandia, MG, Brazil. Leprosy patients (90) were diagnosed according to Ridley and Jopling criteria and they grouped into multibacillary (MB) and paucibacillary (PB) patients. The control group consisted of 61 non-consanguineous contacts. NRAMP1 promoter genotypes were obtained through amplification by the polymerase chain reaction (PCR) followed by the detection through the low ionic-strength single strand conformational polymorphism (LIS-SSCP) electrophoretic technique. There were no significant differences in the allelic and genotypic frequencies for alleles 2, 3, and 4 in relation to the Mitsuda test among patients and household contacts, nor between those with MB and PB forms. However, individuals with a negative lepromin response associated with genotypes 22 and 23 presented a 7- and 8-fold greater chance of developing leprosy, respectively. Therefore, the NRAMP1 gene promoter polymorphism exhibited an interaction with the lepromin response, suggesting that allele 2 of the NRAMP1 promoter is an independent genetic factor that predisposes cells to enable pathogen survival, probably due to its low efficiency in iron transport. However, establishment of the infection and disease development may be conditioned by other immunological and genetic factors.

Is MUC1 polymorphism associated with female infertility?

The transmembrane mucin glycoprotein (MUC1) has an anti-adhesive role, and functions to maintain a non-receptive uterine state. A polymorphic variation of the MUC1 gene has been associated with female infertility due to suspected failure of embryo implantation, based on the significant greater size of the lower allele observed in infertile women. The aim of this study was to confirm this preliminary observation using long polymerase chain reaction (PCR), which has amplified the 60-bp polymorphic variable number of tandem repeat (VNTR) associated to the binding domain of the MUC1 glycoprotein. DNA samples were obtained from 20 women, 10 fertile and 10 infertile, and the VNTR region was amplified through a long PCR procedure. The VNTR size range from 1.6 to 2.9 kb (22-44 motifs). The average size for the lower allele was 1.69 kb for both groups, and for the upper allele was 2.35 and 2.49 kb (P > 0.05) for fertile and infertile groups respectively. The VNTR polymorphism of the MUC1 gene was not associated with female infertility, although its significance cannot be discarded. It is suggested that other regulatory molecules and signals may interact with the MUC1 gene variations, favouring endometrial receptivity and embryo attachment.

[Immunopathology of leprosy: the complexity of the mechanisms of host immune response to Mycobacterium leprae]

Leprosy, whose etiologic agent Mycobacterium leprae, is an illness of ample clinical and immunopathological spectrum. Its clinical manifestations are correlated with distinct immunologic forms, varying from a vigorous immune response mediated by cells to M. leprae, with Th1 standard in the tuberculoid polar region, to an absence of specific cellular response to antigens of M. leprae in the lepromatous polar region, with predominance of Th2 response and exacerbation of humoral response. It is probable that different polymorphic genes determine susceptibility to M. leprae. Additional studies are necessary to clarify the complex interactions between cytokines and the role of the phenotypic diversity of cells network that contribute to the host defense. The comprehension of such mechanisms will provide new insights for the identification of agonists and/or antagonists for pro- or anti-inflammatory effects, and also will indicate possible situations for its appropriate use in immunologic and/or immunotherapeutic interventions.