Visceral Leishmaniasis in Traveler to Guyana Caused by Leishmania siamensis, London, UK.

The parasite Leishmania siamensis is a zoonotic agent of leishmaniasis; infection in animals has been documented in Europe and the United States. Reported authochthonous human infections have been limited to Thailand. We report a case of human visceral Leishmania siamensis infection acquired in Guyana, suggesting colonization in South America.

The Centenary of the Leprosy Relief Association (Lepra)-a moment for celebration and reflection†.

The year 2024 is the Centenary of the foundation of the Leprosy Relief Association (Lepra), formerly the British Empire Leprosy Relief Association (BELRA). The name of the organization changed to the LEProsy Relief Association (LEPRA) in 1976 but has been known as Lepra since 2008. Over the years it has worked closely with members and office holders of the Royal Society of Tropical Medicine and Hygiene. Its work has encompassed activities from the earliest initiatives to ensure appropriate living conditions for those with the disease to the development of leprosy chemotherapy. However, this has now evolved into a strong partnership between the UK- and India-based Lepra hubs, which are carrying out research and public health initiatives ranging from elimination of prejudice against those with leprosy to adopting the recently launched WHO programme for skin NTDs to facilitate integrated control and management regimens. The fight against leprosy has always been a partnership between a wide variety of disease-specific NGOs, health-care workers and international health agencies. The story of Lepra illustrates the central role of these partnerships and national as well as international collaboration.

Clinical aspects of visceral leishmaniasis in HIV infection.

PURPOSE OF REVIEW: HIV infection profoundly impairs the immune mechanisms needed to control and clear Leishmania infection, and outcomes in patients with HIV-associated visceral leishmaniasis are poor. This review summarizes recent work describing the epidemiology, presentation and outcomes of HIV-associated visceral leishmaniasis and discusses advances in diagnosis and management. RECENT FINDINGS: Studies have shown that serological tests can effectively diagnose HIV-associated visceral leishmaniasis, with a sensitivity of 98% if direct agglutination test and rK39 assays are used in combination. Few data exist to guide treatment recommendations. Observational data show high rates of toxicity and treatment failure with pentavalent antimonials, and their use is no longer recommended. Liposomal amphotericin B (L-AmB) is better tolerated, but outcomes are suboptimal, with mortality rates of 7-12%, and parasitological failure rates of up to 32%. Initial reports suggest that L-AmB and miltefosine in combination may be effective in HIV-associated visceral leishmaniasis; however, clinical trial data are lacking. Secondary prophylaxis reduces the rate of relapse, but optimal regimens have not been defined, and optimal timing of antiretroviral therapy initiation in patients with visceral leishmaniasis is unknown. SUMMARY: Recent studies have demonstrated the inadequacy of current treatments for HIV-associated visceral leishmaniasis. Clinical trials are needed to improve early diagnosis, develop combination therapies and define effective secondary prophylaxis regimens.

New findings in the pathogenesis of leprosy and implications for the management of leprosy.

PURPOSE OF REVIEW: This review focuses on recent work in leprosy pathogenesis. New research of both innate and adaptive immune responses to Mycobacterium leprae is described. The proposition that Mycobacterium lepromatosis is a new species causing leprosy is discussed. RECENT FINDINGS: Modulation of the lipid metabolism and reprogramming of adult Schwann cells have both been suggested as mechanisms used by M. leprae to disseminate the disease. New markers associated with localized, disseminated disease or the occurrences of leprosy reactions include the human interferons, CD163, microRNA-21, NOD2, galectin-3 and toll-like receptor 4. The role of keratinocytes instead of macrophages is underlined in the pathogenesis of leprosy. Adaptive immunity reports focus on the role of T regulatory cells and cytokines secreted by T helper cells in leprosy. Finally, a newly identified species named M. lepromatosis has been detected in patients with leprosy and severe erythema nodosum leprosum. SUMMARY: Novel biological pathways have been identified to be associated with the clinical phenotype of leprosy or the occurrence of leprosy reactions. Future work should include larger numbers of clinical samples from across the leprosy spectrum in order to give new insights in the pathogenesis and management of the disease.

A comparison of the change in clinical severity scale score and a retrospective physician assessment of neurological outcome in individuals with leprosy associated nerve function impairment after treatment with corticosteroids.

OBJECTIVES: To determine whether the measured change in score of a validated clinical severity scale reflected physician assessed improvement in individuals who had received corticosteroid therapy for leprosy associated nerve damage. DESIGN: Patients with nerve function impairment who participated in a randomised controlled trial of corticosteroids were classified into two groups using a retrospectively determined physician assessment of improvement. One group consisted of patients who had recovered or improved the other of patients who were unchanged or had deteriorated. The change in the clinical severity scale scores of these two groups was compared. RESULTS: The change in the clinical severity scale scores of the 34 eligible individuals in the two groups were significantly different (P = 0.003). Individuals in the group who recovered or improved had a greater change in severity score than those whose nerve function was unchanged or deteriorated. CONCLUSION: The scale for measuring the severity of leprosy Type 1 reactions (T1Rs) and/or nerve function impairment reflects the clinical improvement of individuals with leprosy associated nerve damage.

Diagnosing and treating leprosy in a non-endemic setting in a national centre, London, United Kingdom 1995-2018.

BACKGROUND: Leprosy is rare in the United Kingdom (UK), but migration from endemic countries results in new cases being diagnosed each year. We documented the clinical presentation of leprosy in a non-endemic setting. METHODS: Demographic and clinical data on all new cases of leprosy managed in the Leprosy Clinic at the Hospital for Tropical Diseases, London between 1995 and 2018 were analysed. RESULTS: 157 individuals with a median age of 34 (range 13-85) years were included. 67.5% were male. Patients came from 34 different countries and most contracted leprosy before migrating to the UK. Eighty-two (51.6%) acquired the infection in India, Sri Lanka, Bangladesh, Nepal and Pakistan. 30 patients (19.1%) acquired leprosy in Africa, including 11 from Nigeria. Seven patients were born in Europe; three acquired their leprosy infection in Africa, three in South East Asia, and one in Europe. The mean interval between arrival in the UK and symptom onset was 5.87 years (SD 10.33), the longest time to diagnosis was 20 years. Borderline tuberculoid leprosy (n = 71, 42.0%), and lepromatous leprosy (n =, 53 33.1%) were the commonest Ridley Jopling types. Dermatologists were the specialists diagnosing leprosy most often. Individuals were treated with World Health Organization recommended drug regimens (rifampicin, dapsone and clofazimine). CONCLUSION: Leprosy is not a disease of travellers but develops after residence in an leprosy endemic area. The number of individuals from a leprosy endemic country reflect both the leprosy prevalence and the migration rates to the United Kingdom. There are challenges in diagnosing leprosy in non-endemic areas and clinicians need to recognise the symptoms and signs of leprosy.

Regulatory T cells in erythema nodosum leprosum maintain anti-inflammatory function.

BACKGROUND: The numbers of circulating regulatory T cells (Tregs) are increased in lepromatous leprosy (LL) but reduced in erythema nodosum leprosum (ENL), the inflammatory complication of LL. It is unclear whether the suppressive function of Tregs is intact in both these conditions. METHODS: A longitudinal study recruited participants at ALERT Hospital, Ethiopia. Peripheral blood samples were obtained before and after 24 weeks of prednisolone treatment for ENL and multidrug therapy (MDT) for participants with LL. We evaluated the suppressive function of Tregs in the peripheral blood mononuclear cells (PBMCs) of participants with LL and ENL by analysis of TNFα, IFNγ and IL-10 responses to Mycobacterium leprae (M. leprae) stimulation before and after depletion of CD25+ cells. RESULTS: 30 LL participants with ENL and 30 LL participants without ENL were recruited. The depletion of CD25+ cells from PBMCs was associated with enhanced TNFα and IFNγ responses to M. leprae stimulation before and after 24 weeks treatment of LL with MDT and of ENL with prednisolone. The addition of autologous CD25+ cells to CD25+ depleted PBMCs abolished these responses. In both non-reactional LL and ENL groups mitogen (PHA)-induced TNFα and IFNγ responses were not affected by depletion of CD25+ cells either before or after treatment. Depleting CD25+ cells did not affect the IL-10 response to M. leprae before and after 24 weeks of MDT in participants with LL. However, depletion of CD25+ cells was associated with an enhanced IL-10 response on stimulation with M. leprae in untreated participants with ENL and reduced IL-10 responses in treated individuals with ENL. The enhanced IL-10 in untreated ENL and the reduced IL-10 response in prednisolone treated individuals with ENL was abolished by addition of autologous CD25+ cells. CONCLUSION: The findings support the hypothesis that the impaired cell-mediated immune response in individuals with LL is M. leprae antigen specific and the unresponsiveness can be reversed by depleting CD25+ cells. Our results suggest that the suppressive function of Tregs in ENL is intact despite ENL being associated with reduced numbers of Tregs. The lack of difference in IL-10 response in control PBMCs and CD25+ depleted PBMCs in individuals with LL and the increased IL-10 response following the depletion of CD25+ cells in individuals with untreated ENL suggest that the mechanism of immune regulation by Tregs in leprosy appears independent of IL-10 or that other cells may be responsible for IL-10 production in leprosy. The present findings highlight mechanisms of T cell regulation in LL and ENL and provide insights into the control of peripheral immune tolerance, identifying Tregs as a potential therapeutic target.

What is the evidence that the putative Mycobacterium lepromatosis species causes diffuse lepromatous leprosy?

Han et al. have made a retrospective isolation of DNA from two patients with fatal Lucio's phenomenon. This DNA does have some molecular differences to M. leprae and may constitute a variant of M. leprae. However the experiments and data needed to confirm that this is a new leprosy-causing species have not yet been done. We have outlined the work that does need to be done. For the moment the assertion that 'M. lepromatosis' is a new leprosy-causing species is not proven.

Leishmaniasis.

Leishmaniasis is an uncommon infectious disease in the UK with a variety of clinical presentations. Physicians should remember to consider this diagnosis in patients with an appropriate travel history (including the Mediterranean basin) and seek help with diagnostics from a specialised parasitology laboratory. Treatment regimens may be unfamiliar to the general physician, and thus should also be discussed with an expert.

Clinical diversity and treatment results in Tegumentary Leishmaniasis: A European clinical report in 459 patients.

BACKGROUND: Cutaneous leishmaniasis (CL) is frequent in travellers and can involve oro-nasal mucosae. Clinical presentation impacts therapeutic management. METHODOLOGY: Demographic and clinical data from 459 travellers infected in 47 different countries were collected by members of the European LeishMan consortium. The infecting Leishmania species was identified in 198 patients. PRINCIPAL FINDINGS: Compared to Old World CL, New World CL was more frequently ulcerative (75% vs 47%), larger (3 vs 2cm), less frequently facial (17% vs 38%) and less frequently associated with mucosal involvement (2.7% vs 5.3%). Patients with mucosal lesions were older (58 vs 30 years) and more frequently immunocompromised (37% vs 3.5%) compared to patients with only skin lesions. Young adults infected in Latin America with L. braziliensis or L. guyanensis complex typically had an ulcer of the lower limbs with mucosal involvement in 5.8% of cases. Typically, infections with L. major and L. tropica acquired in Africa or the Middle East were not associated with mucosal lesions, while infections with L. infantum, acquired in Southern Europe resulted in slowly evolving facial lesions with mucosal involvement in 22% of cases. Local or systemic treatments were used in patients with different clinical presentations but resulted in similarly high cure rates (89% vs 86%). CONCLUSION/SIGNIFICANCE: CL acquired in L. infantum-endemic European and Mediterranean areas displays unexpected high rates of mucosal involvement comparable to those of CL acquired in Latin America, especially in immunocompromised patients. When used as per recommendations, local therapy is associated with high cure rates.

An assessment of the reported impact of the COVID-19 pandemic on leprosy services using an online survey of practitioners in leprosy referral centres.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has led to governments implementing a variety of public health measures to control transmission and has affected health services. Leprosy is a communicable neglected tropical disease caused by Mycobacterium leprae and is an important health problem in low- and middle-income countries. The natural history of leprosy means that affected individuals need long-term follow-up. The measures recommended to reduce transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can create barriers to health services. We evaluated the impact of the COVID-19 epidemic response on leprosy services and disease management. METHODS: We conducted a cross-sectional online survey with healthcare professionals in leprosy referral centres. RESULTS: Eighty percent of leprosy diagnostic services were reduced. All respondents reported that multidrug therapy (MDT) was available but two reported a reduced stock. Clinicians used alternative strategies such as telephone consultations to maintain contact with patients. However, patients were not able to travel to the referral centres. DISCUSSION: This study highlights the effects of the initial phase of the SARS-CoV-2 pandemic on leprosy services in a range of leprosy-endemic countries. Many services remained open, providing leprosy diagnosis, MDT and leprosy reaction medications. Centres developed innovative measures to counter the negative impacts of the COVID-19 pandemic.

Leprosy and HIV, where are we at?

The impact of leprosy and HIV co-infection is an evolving picture. Surprisingly the outcomes that were feared, of more lepromatous disease has not materialised. But with the roll-out of antiretroviral therapy, the emergence of leprosy as Immune Reconstitution Inflammatory Syndrome is re-focusing attention on the characteristics of this important co-infection.

Impacts of the diagnosis of leprosy and of visible impairments amongst people affected by leprosy in Cebu, the Philippines.

PURPOSE: To quantify the impact of the diagnosis of leprosy and of visible impairments in people affected by leprosy. SUBJECTS AND METHODS: Three interview-based questionnaires designed to measure activity limitation, participation restriction, and general self-efficacy were used to collect data from three Groups. Group 1: leprosy affected people with visible impairment, Group 2: newly diagnosed leprosy patients with no visible impairment, Group 3: patients with other skin diseases symptomatic for more than 1 month. RESULTS: One hundred and eight subjects were recruited. The subjects with visible impairments (Group 1) had higher levels of participation restriction than those with skin disease (P0.012), and participation restriction was similar between subjects in Groups 2 and 3 (P0-305). The people in Group 1 (35 subjects) also reported significantly more activity limitation compared to the people in either Group 2 (35 subjects) or Group 3 (38 subjects) (P 0-001, respectively). The subjects in Group 2 had no significant activity limitation compared with those in Group 3 (P0.338). A multivariate analysis showed that severe visible impairment was a risk factor for activity limitation (odds ratio 5.68, 95% CI: 1.09-297, P0.039) and a low level of self-efficacy (Odds ratio 6.38, 95% CI: 1.06-38.3, P0-043) among people affected by leprosy. CONCLUSION: Visible impairments affected the activities and attitudes of people affected by leprosy. However, others without visible impairment, had activity limitations, participation restrictions and levels of general self-efficacy that were similar to patients with other skin diseases. Prevention of visible impairments should be considered a key intervention for stigma reduction.

Mechanical detection and pain thresholds: comparability of devices using stepped and ramped stimuli.

Quantitative sensory testing is used to assess somatosensory function in humans. The protocol of the German Research Network on Neuropathic Pain (DFNS) provides comprehensive normative values using defined tools; however, some of these may not be feasible in low-resource settings. OBJECTIVES: To compare the standard DFNS devices for assessment of mechanosensory function to a low resource tool, the Sorri-Bauru-monofilaments. METHODS: Mechanical detection thresholds (MDT), pain thresholds (MPT), and suprathreshold pinprick ratings (pain sensitivity: MPS) were measured over cheek, hand dorsum, and fingertip in 13 healthy subjects (7 female, aged 21-44 years). Mechanical detection threshold was assessed with DFNS standard glass monofilaments (0.25-512 mN, 0.5 mm tip) and nylon monofilaments (Sorri-Bauru; 0.5-3000 mN). MPT was assessed with DFNS standard cylindrical probes (8-512 mN, 0.25 mm tip), Sorri-Bauru monofilaments, and with ramped stimuli using an electronic von Frey aesthesiometer (10 mN/s or 100 mN/s, 0.20 mm tip). MPS was measured in response to stepped and ramped pinpricks (128 and 256 mN). RESULTS: Mechanical detection thresholds were the same for DFNS and Sorri-Bauru monofilaments. For MPT, Sorri-Bauru filaments yielded lower values than PinPricks over face but not hand. Pain thresholds were higher at all test sites for ramped than stepped pinpricks (P < 0.01). Suprathreshold ratings were lower for ramped than stepped pinpricks (P < 0.05). CONCLUSION: Sorri-Bauru filaments are acceptable substitutes for DFNS standards in estimating tactile sensitivity, but are not consistent with standard probes for pinprick sensitivity because of their nonstandardized tips. Ramped stimuli overestimated MPT and underestimated MPS due to reaction time artefacts and therefore need their own normative values.