Clinical aspects and management of cutaneous leishmaniasis in rheumatoid patients treated with TNF-α antagonists

Leishmania infantum infection after visiting southern Spain in patients on biological treatment; an observational, longitudinal, cohort study

BACKGROUND

Reports of leishmaniasis in immunosuppressed patients after visiting the Mediterranean Basin are becoming increasingly common. Still, awareness of the risk of infection and its clinical manifestations may be insufficient among healthcare professionals in the travellers' home countries.

METHODS

This observational, longitudinal study included 47 patients from Sweden with rheumatic disease and ongoing immunomodulatory treatment, who visited a rehabilitation centre in southern Spain where leishmaniasis is endemic. Patients were evaluated for clinical signs of leishmaniasis at baseline and after three years. Patients with leishmaniasis were followed for 4-5 years. The treatment outcome was assessed by clinical evaluation and determination of the cell-mediated immunological response to Leishmania by a whole blood cytokine release assay.

RESULTS

Seven patients (15%) were diagnosed with leishmaniasis. The median time from exposure to the onset of symptoms was 3 [1-17] months. The median delay between the onset of symptoms and treatment start was 9 [1-12] months. All patients with leishmaniasis responded well to treatment. Only one patient had a relapse, which occurred within the first year.

CONCLUSION

Healthcare professionals need to be aware of the increased risk of leishmaniasis for travellers who are immunosuppressed. Knowledge of the symptoms is crucial for a timely diagnosis and early treatment.

Non-Endemic Leishmaniases Reported Globally in Humans between 2000 and 2021—A Comprehensive Review

Leishmaniases are human and animal parasitic diseases transmitted by phlebotomine sand flies. Globalization is an important driver of the burden and in the current dynamics of these diseases. A systematic review of articles published between 2000 and 2021 was conducted using the PubMed search engine to identify the epidemiology and clinical management of imported human leishmaniases as a fundamental step to better manage individual cases and traveler and migrant health from a global perspective. A total of 275 articles were selected, representing 10,341 human imported cases. Identified drivers of changing patterns in epidemiology include conflict and war, as well as host factors, such as immunosuppression, natural and iatrogenic. Leishmania species diversity associated with different clinical presentations implies diagnostic and treatment strategies often complex to select and apply, especially in non-endemic settings. Thus, diagnostic and management algorithms for medical clinical decision support are proposed. Increased surveillance of non-endemic cases, whether in vulnerable populations such as refugees/migrants and immunocompromised individuals or travelers, could improve individual health and mitigate the public health risk of introducing Leishmania species into new areas.

Susceptibility to Intracellular Infections: Contributions of TNF to Immune Defense

An interesting puzzle is the fact that an infection of a tumor necrosis factor α (TNF)-deficient host with pathogens such as bacteria or parasites that reside intracellularly inevitably ends fatally. Is this due to one specific role of TNF in the immune defense or are different functions responsible for this outcome? In this review we provide an update of the functions of TNF in the defense against the intracellular pathogens Listeria monocytogenes, Mycobacterium tuberculosis, and Leishmania major. Furthermore, we discuss the role of TNF in the generation of proinflammatory macrophages in mouse models of infection and summarize briefly the potential consequences of anti-TNF treatment for infectious diseases.

Leishmaniasis and tumor necrosis factor alpha antagonists in the Mediterranean basin. A switch in clinical expression

Background

Tumor necrosis factor alpha (TNF-α) blockers are recognized as a risk factor for reactivation of granulomatous infections. Leishmaniasis has been associated with the use of these drugs, although few cases have been reported.

Methodology

We performed a retrospective observational study including patients with confirmed leishmaniasis acquired in the Mediterranean basin that were under TNF-α blockers therapy at the moment of the diagnosis. Patients diagnosed in our hospital from 2008 to 2018 were included. Moreover, a systematic review of the literature was performed and cases fulfilling the inclusion criteria were also included.

Principal findings

Forty-nine patients were analyzed including nine cases from our series. Twenty-seven (55.1%) cases were male and median age was 55 years. Twenty-five (51%) patients were under infliximab treatment, 20 (40.8%) were receiving adalimumab, 2 (4.1%) etanercept, one (2%) golimumab and one (2%) a non-specified TNF-α blocker. Regarding clinical presentation, 28 (57.1%) presented as cutaneous leishmaniasis (CL), 16 (32.6%) as visceral leishmaniasis (VL) and 5 (10.2%) as mucocutaneous leishmaniasis (MCL). All VL and MCL patients were treated with systemic therapies. Among CL patients, 13 (46.4%) were treated with a systemic drug (11 received L-AmB, one intramuscular antimonials and one miltefosine) while 14 (50%) patients were given local treatment (13 received intralesional pentavalent antimonials, and one excisional surgery). TNF-α blockers were interrupted in 32 patients (65.3%). After treatment 5 patients (10.2%) relapsed. Four patients with a CL (3 initially treated with local therapy maintaining TNF-α blockers and one treated with miltefosine) and one patient with VL treated with L-AmB maintaining TNF-α blockers.

Conclusions

This data supports the assumption that the blockage of TNF-α modifies clinical expression of leishmaniasis in endemic population modulating the expression of the disease leading to atypical presentations. According to the cases reported, the best treatment strategy would be a systemic drug and the discontinuation of the TNF-α blockers therapy until clinical resolution.

Tumor necrosis factor alpha (TNF-α) blockers are widely used in numerous inflammatory diseases such rheumatoid arthritis, psoriasis or inflammatory bowel diseases. They have been recognized as a risk factor for reactivation of granulomatous infections. Although few cases have been reported, Leishmaniasis has been associated with the use of these drugs. Leishmania infantum is the main causative agent of leishmaniasis in Southern Europe and is prone to produce the visceral form. However, TNF-α has been implicated in the initial events of the infection mediating the disease expression. In our series, we have observed a surprisingly high proportion of cutaneous form (32.6%) and muco-cutaneous form (10.2%). Clinical outcome observed in this series is also unusual. Four cases (14.3%) with cutaneous leishmaniasis who received local therapy relapsed. Among patients with visceral leishmaniasis, one patient who maintained TNF-α blockers therapy relapsed despite etiological treatment. This data supports the assumption that the blockage of TNF-α modifies clinical expression of leishmaniasis leading to atypical presentations. According to the cases reported we proposed as best treatment strategy a systemic drug and the discontinuation of the TNF-α blockers therapy until clinical resolution.

Imported visceral leishmaniasis and immunosuppression in seven Norwegian patients

Background

Visceral leishmaniasis (VL) is a protozoal disease that may be aggravated by immunosuppression. In recent years, a growing number of patients with chronic diseases use biological treatment. When such immunosuppressed patients travel to endemic areas, they are facing the risk of VL. Increased incidence of leishmaniasis is reported in endemic areas like the Mediterranean basin, an area frequently visited by Norwegian tourists. This may lead to an increased number of patients, many presenting to health personnel unfamiliar with the disease, in their home countries.

Methods

We reviewed the files of seven immunosuppressed patients with VL, admitted to Oslo and Haukeland University Hospitals in Norway in the period 2009-2018.

Results

The patients were 41-83 (median 66) years of age; four had rheumatic disease all of whom used methotrexate; one had advanced HIV infection, one had inflammatory bowel disease and one had myelofibrosis. Leishmania infantum was confirmed in five patients by polymerase chain reaction (PCR) and sequencing. In the remaining two patients, a definite Leishmania species could not be identified. All patients had a history of recent recreational travel to Spain. Most patients underwent extensive diagnostic work-up before diagnosed with VL. All received treatment with liposomal amphotericin B and all were cured; albeit two after re-treatment due to relapse.

Conclusions

Visceral leishmaniasis is a potentially life-threatening but usually treatable condition. It is endemic in Southern Europe, including popular tourist destinations such as the Mediterranean basin. It is relatively unknown to most medical practitioners in non-endemic areas and clinical vigilance is required to identify those who are infected.

Cytokine Effect of TLR3, TLR4, and TLR7 Agonists Alone or Associated with Leishmania infantum Antigen on Blood from Dogs

Activation of toll-like receptors (TLRs) has been shown to play an important role in leishmaniosis by enhancing the parasite specific immune responses to control infection. However, the role of TLR agonists has not been studied in detail in dogs. The aim of this study was to determine the effect of TLR3, TLR4, and TLR7 agonists (TLR3a, TLR4a, and TLR7a) alone or in combination with Leishmania infantum antigen (LSA) on TNF-α and IL-6 production in blood from dogs living in endemic areas of canine leishmaniosis (CanL). Twenty-four healthy dogs from Catalonia (n=14) and Ibizan hound dogs from the island of Mallorca (n=10) were enrolled. Whole blood with TLR3a, TLR4a, and TLR7a alone or combined with LSA were cultured separately, and IFN-γ, TNF-α, and IL-6 were measured by ELISA. A significant increase of TNF-α was found for all conditions studied compared to medium alone. Stimulation with TLR4a (p=0.0001) and TLR7a (p=0.005) presented a significantly marked increase in TNF-α and IL-6 production compared to TLR3a. Importantly, significantly higher TNF-α production was found in LSA+TLR4a (p=0.0001) stimulated blood and LSA+TLR7a (p=0.005) compared to LSA alone. All dogs showed higher TNF-α production after LSA+TLR7a compared to TLR7a (p=0.047) and LSA+TLR3a compared to TLR3a (p=0.052). These data indicate a marked inflammatory cytokine effect of TLR4a and TLR7a on blood from healthy dogs living in endemic areas of CanL. Additionally, LSA+TLR7a promoted a synergistic proinflammatory effect with TNF-α in all dogs. Those findings suggest an active role of TLRs in proinflammatory responses, which might be strongly involved in the process of disease resolution.

Subclinical Leishmania infection in patients with rheumatic diseases under biological drugs

PURPOSE

Climate changes and immunosuppression are influencing the spread of leishmaniasis and re-emergence in Northern Italy, respectively. We evaluated the prevalence of subclinical leishmaniasis in patients from a Northern Italian region with chronic inflammatory rheumatism (CIRD) receiving biological drugs (BD) and correlated it to the area of residence.

METHODS

DNA from PBMC of patients affected by CIRD treated with either BD for at least 5 years (Group A) or other immunosuppressive drugs (Group B) was investigated by a qPCR for Leishmania infantum kDNA and compared to healthy subjects (Group C). Variables such as sex and age, rural areas, dog ownership, type of BD administered and association between BD and steroids, were evaluated by statistical analysis.

RESULTS

A higher proportion of L. infantum DNA positivity was found in Group A than in Group C (p < 0.05), while no parasite DNA was detected in Group B. In Group A, 18/50 patients (36%) had higher rates of parasite DNA (from 1 to 136 to 1.000.000 copies/ml) than Group C (from 1 to 10 copies/ml). 14/18 (77.7%) of positive patients from Group A lived in rural areas, but no statistical differences occurred in relation to dog ownership or BD type (p < 0.0003).

CONCLUSIONS

We can speculate that exposure to rural areas appears to be a factor closely linked with the risk of developing Leishmania subclinical infection. A screening with molecular methods in patients with CIRD treated with BD living in these areas and monitoring Leishmania DNA during such therapies, would be mandatory to prevent delay in diagnosis should VL symptoms appear.

The Binomial Parasite-Host Immunity in the Healing Process and in Reactivation of Human Tegumentary Leishmaniasis

Leishmaniasis is a vector-borne infectious disease caused by different species of protozoa from the Leishmania genus. Classically, the disease can be classified into two main clinical forms: Visceral (VL) and Tegumentary (TL) leishmaniasis. TL is a skin/mucosal granulomatous disease that manifests mainly as cutaneous localized or disseminated ulcers, papules diffusely distributed, mucosal lesions or atypical lesions. Once the etiology of the infection is confirmed, treatment can take place, and different drugs can be administered. It has already been shown that, even when the scar is clinically evident, inflammation is still present in the native tissue, and the decrease of the inflammatory process occurs slowly during the 1st years after clinical healing. The maintenance of residual parasites in the scar tissue is also well documented. Therefore, it is no longer a surprise that, under some circumstances, therapeutic failure and/or lesion reactivation occurs. All over the years, an impressive amount of data on relapses, treatment resistance and lesion reactivation after healing has been collected, and several factors have been pointed out as having a role in the process. Different factors such as Leishmania species, parasite variability, Leishmania RNA virus 1, parasite load, parasite persistence, age, nutritional status, gender, co-morbidities, co-infection, pregnancy, immunosuppression, lesion duration, number and localization of lesions, drug metabolism, irregular treatment and individual host cellular immune response were described and discussed in the present review. Unfortunately, despite this amount of information, a conclusive understanding remains under construction. In addition, multifactorial influence cannot be discarded. In this context, knowing why leishmaniasis has been difficult to treat and control can help the development of new approaches, such as drugs and immunotherapy in order to improve healing maintenance. In this sense, we would like to highlight some of the findings that may influence the course of Leishmania infection and the therapeutic response, with an emphasis on TL.

Case Report: Diffuse Cutaneous Leishmaniasis by Leishmania infantum in a Patient Undergoing Immunosuppressive Therapy: Risk Status in an Endemic Mediterranean Area

This case report highlights the risk of severe cutaneous leishmaniasis (CL) by Leishmania infantum in patients undergoing immunosuppressant therapy who either live in an endemic area or are visiting in the transmission season. The case patient, resident in Majorca (Balearic Islands), presented 12 disseminated erythematous skin lesions, 1-6 cm in diameter, located on the scalp, cheek, umbilical region, and lower extremities 8 years after undergoing anti-tumor necrosis factor (TNF) therapy. Parasite presence in peripheral blood and high levels of specific antibodies were also observed, indicating a possible risk of CL shifting toward a visceral infection. However, once CL was diagnosed, anti-TNF therapy was discontinued and liposomal amphotericin B was administered, resulting in a complete healing of lesions, no Leishmania DNA detection in blood, and an important serological decrease in antibodies. The lack of data on the supposed epidemiological association between leishmaniasis and immunosuppressive therapy highlights the importance of implementing surveillance systems in endemic areas. No obvious relationship was found based on the data provided by the Balearic Islands Epidemiological System, in contrast with data reported in nearby endemic areas. This indicates that if the suspected association is to be clarified, greater efforts are needed to report information about concomitant diseases and therapies in leishmaniasis patients.

Toll-like receptors 2, 4, and 9 expressions over the entire clinical and immunopathological spectrum of American cutaneous leishmaniasis due to Leishmania(V.) braziliensis and Leishmania (L.) amazonensis

Leishmania (V.) braziliensis and Leishmania(L.) amazonensis are the most pathogenic agents of American Cutaneous Leishmaniasis in Brazil, causing a wide spectrum of clinical and immunopathological manifestations, including: localized cutaneous leishmaniasis (LCLDTH+/++), borderline disseminated cutaneous leishmaniasis (BDCLDTH±), anergic diffuse cutaneous leishmaniasis (ADCLDTH-), and mucosal leishmaniasis (MLDTH++++). It has recently been demonstrated, however, that while L. (V.) braziliensis shows a clear potential to advance the infection from central LCL (a moderate T-cell hypersensitivity form) towards ML (the highest T-cell hypersensitivity pole), L. (L.) amazonensis drives the infection in the opposite direction to ADCL (the lowest T-cell hypersensitivity pole). This study evaluated by immunohistochemistry the expression of Toll-like receptors (TLRs) 2, 4, and 9 and their relationships with CD4 and CD8 T-cells, and TNF-α, IL-10, and TGF-β cytokines in that disease spectrum. Biopsies of skin and mucosal lesions from 43 patients were examined: 6 cases of ADCL, 5 of BDCL, and 11 of LCL caused byL. (L.) amazonensis; as well as 10 cases of LCL, 4 of BDCL, and 6 of ML caused byL. (V.) braziliensis. CD4+ T-cells demonstrated their highest expression in ML and, in contrast, their lowest in ADCL. CD8+ T-cells also showed their lowest expression in ADCL as compared to the other forms of the disease. TNF-α+showed increased expression from ADCL to ML, while IL-10+and TGF-β+ showed increased expression in the opposite direction, from ML to ADCL. With regards to TLR2, 4, and 9 expressions, strong interactions of TLR2 and 4 with clinical forms associated with L. (V.) braziliensis were observed, while TLR9, in contrast, showed a strong interaction with clinical forms linked to L. (L.) amazonensis. These findings strongly suggest the ability of L. (V.) braziliensis and L. (L.) amazonensis to interact with those TLRs to promote a dichotomous T-cell immune response in ACL.

Addressing a clinical challenge: guidelines for the diagnosis and treatment of leishmaniasis

Leishmaniasis is a chronic intracellular parasitic infection that travelers, immigrants, deployed military personnel, and refugees from endemic global areas acquire from the bite of infected sand flies and carry with them, including to non-endemic countries where leishmaniasis may be an unfamiliar illness to medical providers. This commentary discusses the first clinical practice guidelines produced by the Infectious Diseases Society of America and American Society of Tropical Medicine and Hygiene for the diagnosis and management of leishmaniasis, targeted for clinicians in North America.

Cutaneous leishmaniasis associated with anti-tumour necrosis factor-α drugs: an emerging disease

Leishmaniasis is endemic in several geographic areas of the world. In each of these areas, particular species of Leishmania with differing aggressiveness to humans predominate. In the European Mediterranean basin, cutaneous leishmaniasis usually presents with discrete, self-healing skin lesions. Although it is known that tumour necrosis factor (TNF) inhibitors may increase the risk of developing infections such as tuberculosis, there is scarce literature on Leishmania infections in patients treated with these drugs. In recent months, we have observed three patients resident in the Catalan coast of Spain who were treated with TNF inhibitors for Crohn disease, and who developed unusually large and persistent cutaneous lesions of leishmaniasis. These lesions responded only to treatment with intravenous liposomal amphotericin B. In countries with a high incidence of infection by aggressive species of Leishmania, serological screening may be indicated to detect a possible latent leishmanial infection before prescription of TNF inhibitors.

Diagnosis and Treatment of Leishmaniasis: Clinical Practice Guidelines by the Infectious Diseases Society of America (IDSA) and the American Society of Tropical Medicine and Hygiene (ASTMH)

It is important to realize that leishmaniasis guidelines cannot always account for individual variation among patients. They are not intended to supplant physician judgment with respect to particular patients or special clinical situations. The IDSA and ASTMH consider adherence to these guidelines to be voluntary, with the ultimate determinations regarding their application to be made by the physician in the light of each patient's individual circumstances.

Miltefosine for Mucosal and Complicated Cutaneous Old World Leishmaniasis: A Case Series and Review of the Literature

Complicated Old World cutaneous leishmaniasis (OWCL) and Old World mucosal leishmaniasis (OWML) constitute an indication for systemic treatment. To date, there no controlled clinical studies that compare treatment options for these diseases. We compiled a case series of 24 cases successfully treated with miltefosine. We conclude that oral miltefosine is an effective treatment option for both OWCL and OWML.

[Common tropical infections with protozoans, worms and ectoparasites]

Infectious diseases of the skin have become rarer in industrialized nations, but they still affect a considerable part of the population in tropical regions. Skin diseases induced by protozoa, worms and ectoparasites are among the 17 "neglected tropical diseases" defined by the WHO (leishmaniasis, dracunculiasis, lymphatic filariasis, onchocerciasis). Skin symptoms in travellers returning from the tropics may challenge dermatologists in Germany regarding differential diagnostic assessment and therapy. Among the 12 most frequent skin diseases in travellers are cutaneous larva migrans, leishmaniasis and myiasis. In this review, diagnosis, treatment and prevention of some the most relevant tropical dermatoses due to protozoa, worms and ectoparasites are discussed.

LeishMan recommendations for treatment of cutaneous and mucosal leishmaniasis in travelers, 2014

BACKGROUND

Treatment of cutaneous leishmaniasis (CL) and mucosal leishmaniasis (ML) in travelers is still controversial. Over the last decade, national and international consortia have published recommendations for treating CL in travelers. These guidelines harmonize many issues, but there are some discrepancies.

METHODS

Leishmania parasites causing CL can now be genotyped by polymerase chain reaction techniques for detecting Leishmania DNA. Therefore, treatment recommendations can now be species based rather than based on geographical exposure. To review the evidence on which the recommendations were based, "LeishMan" (Leishmaniasis Management), a group of experts from 13 institutions in eight European countries, performed a PubMed MEDLINE) literature search and considered unpublished evidence and the experts' own personal experiences. The Oxford evidence grading system was used to evaluate the information.

RESULTS AND CONCLUSION

In this article, the authors provide practical treatment recommendations for imported CL and ML in Europe, drawn up from the review by the European experts.