Pediatric Cutaneous Leishmaniasis in an Endemic Region in Turkey: A Retrospective Analysis of 8786 Cases during 1998-2014

Sampling is decisive to determination of Leishmania (Viannia) species

BACKGROUND

Accuracy of molecular tools for the identification of parasites that cause human cutaneous leishmaniasis (CL) could largely depend on the sampling method. Non-invasive or less-invasive sampling methods such as filter paper imprints and cotton swabs are preferred over punch biopsies and lancet scrapings for detection methods of Leishmania based on polymerase chain reaction (PCR) because they are painless, simple, and inexpensive, and of benefit to military and civilian patients to ensure timely treatment. However, different types of samples can generate false negatives and there is a clear need to demonstrate which sample is more proper for molecular assays.

METHODOLOGY

Here, we compared the sensitivity of molecular identification of different Leishmania (Viannia) species from Peru, using three types of sampling: punch biopsy, filter paper imprint and lancet scraping. Different composite reference standards and latent class models allowed to evaluate the accuracy of the molecular tools. Additionally, a quantitative PCR assessed variations in the results and parasite load in each type of sample.

PRINCIPAL FINDINGS

Different composite reference standards and latent class models determined higher sensitivity when lancet scrapings were used for sampling in the identification and determination of Leishmania (Viannia) species through PCR-based assays. This was consistent for genus identification through kinetoplastid DNA-PCR and for the determination of species using FRET probes-based Nested Real-Time PCR. Lack of species identification in some samples correlated with the low intensity of the PCR electrophoretic band, which reflects the low parasite load in samples.

CONCLUSIONS

The type of clinical sample can directly influence the detection and identification of Leishmania (Viannia) species. Here, we demonstrated that lancet scraping samples consistently allowed the identification of more leishmaniasis cases compared to filter paper imprints or biopsies. This procedure is inexpensive, painless, and easy to implement at the point of care and avoids the need for anesthesia, surgery, and hospitalization and therefore could be used in resource limited settings for both military and civilian populations.

Magnitude and associated factors of cutaneous leishmaniasis among patients visiting Nefas Mewcha primary hospital, Northern Ethiopia, 2022: An institution-based Cross-sectional study

BACKGROUND

Cutaneous leishmaniasis (CL) is the most common neglected tropical disease, causing stigmatised skin lesions. It is an important public health concern, with 95% of cases occurring in low-income and middle-income countries. Despite its long-recognized endemicity and psychosocial impacts, it is largely overlooked.

OBJECTIVE

The main aim of this study is to investigate the magnitude and associated factors of CL in north-central Ethiopia.

DESIGN

An institution-based cross-sectional study was conducted.

SETTING

The study was conducted in Nefas Mewcha Primary Hospital (NMPH), north-central Ethiopia.

PARTICIPANTS

The study was conducted among 332 individuals visiting NMPH from June to July 2022.

PRIMARY AND SECONDARY OUTCOMES

The primary outcome was to estimate the burden of CL among patients visiting NMPH, and the secondary outcome was to identify factors associated with the presence or absence of CL. The association between predictor variables and CL was assessed using a binary logistic regression model. Statistical significance was declared at a p _value of <0.05.

RESULT

Out of the 332 study participants, 63 patients sought medical care with skin lesions, and 61 (18.37%, 95% CI: 14.5% to 22.9%) were patients with CL. Localized CL was the predominant type (86.9%). Male sex (adjusted OR (AOR): 4.51; 95% CI 1.94 to 10.45), older age (AOR 0.91, 95% CI: 0.87 to 0.94), secondary and tertiary educational status (AOR: 0.18, 95% CI: 0.05 to 0.6), poor knowledge of CL (AOR: 4.02, 95% CI: 1.81 to 9.76) and living with domestic animals (AOR: 5.29, 95% CI 3.24 to 7.5) were identified as predictors of CL.

CONCLUSION

In the study area, the magnitude of CL was found to be high. Being male and young, having low educational status, having poor knowledge and living with domestic animals increase the risk of acquiring CL. As a result, increasing the knowledge of the community through scaling up of health education programmes and reducing activities that increase individuals' exposure to sandflies should be prioritised.

A long-lasting emerging epidemic of anthroponotic cutaneous leishmaniasis in southeastern Iran: population movement and peri-urban settlements as a major risk factor

Background

Epidemics of cutaneous leishmaniasis (CL) are occurring more frequently and spreading faster and farther than before in many areas of the world. The present study aimed to assess a long-lasting emerging epidemic (2005–2019) of 5532 cases with anthroponotic CL (ACL) in peri-urban areas of Kerman city in southeastern Iran.

Methods

This descriptive-analytical study was carried out for 15 years in Kerman province, southeastern Iran. The data were passively obtained through the health surveillance system and the Kerman Leishmaniasis Research Center. Every subject was diagnosed using direct smear microscopy. The representative causative agent was further examined by ITS1-PCR, PCR-RFLP, 7SL RNA gene sequencing and phylogenetic analyses. For each subject, a case report form designating demographic and clinical data was recorded.

Results

A different pattern of ACL incidence was found in peri-urban areas compared to that in the city of Kerman. The incidence rate of ACL cases has significantly increased (P < 0.001) from 2005 to 2016 in new settlements with a gradual decline after that. The overall average risk of contracting the disease was 7.6 times higher in peri-urban areas compared to Kerman city, an old endemic focus. All isolates consisting of six variants were confirmed to be Leishmania tropica. The overall pattern of the ACL infection indicates that the etiological agent of ACL is propagated and transmitted by the bite of female Phlebotomus sergenti sandflies from person to person from dissimilar clones as reflected by the complexity of the migrants’ backgrounds in the province.

Conclusions

The movement of populations and establishment of new settlements in peri-urban areas close to endemic areas are major risk factors for and are directly linked to CL. The underlying factors of this emerging ACL epidemic caused by L. tropica were disasters and droughts, among others. A robust commitment to a multilateral approach is crucial to make improvements in this area. This will require decisive coordinated actions through all governmental factions and non-governmental organizations. Furthermore, active and passive case detection strategies, early diagnosis, and effective treatment could help control the disease.

Clinical, microscopic and molecular presentation in pediatric versus adult old world cutaneous Leishmaniasis

BACKGROUND

Cutaneous leishmaniasis (CL) is an emerging uncontrolled tropical parasitic disease in endemic and nonendemic areas with a high prevalence in the pediatric age group.

METHOD

A total of 382 individuals from Lebanon, Saudi Arabia, Pakistan, and Syria diagnosed with CL by punch biopsy/scrapings were grouped into adults (>18 years) and pediatrics (≤18 years). Data recorded included clinical features [number, location, type, size, and extensiveness (size larger than 3 cm, more than 5 lesions per patient, lesion present for more than 12 months, special types, disfiguring lesion or closeness to vital sensory organs) of lesions] and microscopic findings [Ridley's Parasitic Index and Ridley's Pattern]. In addition, molecular confirmation and speciation were performed.

RESULTS

In comparison with adults, patients in the pediatric group (n = 158, 41.4%) showed significantly higher number of lesions, more facial involvement, and more extensive disease (P < .05). Microscopically, a more advanced Ridley's pattern was observed. The other variables did not show statistical difference between the two groups.

CONCLUSION

Historically, CL has been known to be a neglected tropical disease of poverty and pediatric predilection. In our pediatric group, CL manifests with more extensive disease clinically mirrored by more advanced lesions microscopically.

Modelling the number of dermal lesions in anthroponotic cutaneous leishmaniasis and its associated factors in Herat province, western Afghanistan, during 2012-2013

Cutaneous leishmaniasis (CL), caused by Leishmania tropica, is the main causative agent of CL in the Herat province, western Afghanistan. In CL patients, one of the most important indicators for reducing the amount of body damage and the choice of treatment is the number of dermal lesions, but there is no strong evidence in this regard. Therefore, using count regression models, the main objective of this historical cohort study was to identify the distribution of the number of dermal lesions and determine the associated factors among CL patients referring to leishmaniasis reference laboratory in Herat province, from January 2012 to December 2013. In a total of 4,127 clinically suspected CL cases, 50.20% were female and 49.80% male. Based on the results of ZINB model, which is the best model suggested by goodness-of-fit criteria, age variables (IRR = 1.007), duration of lesion (6-12 weeks compared to < 6 weeks with IRR = 1.36 and >12 weeks with IRR = 1.39 compared to <6 weeks), type of lesion(both nodule and ulcer compared to papule with IRR = 2.03), location of lesion (trunk with IRR = 1.90, upper with IRR = 1.66, lower with IRR = 1.61 and mix with IRR = 10.35 compared to head/neck/ears) and type of lesion (ulcer compared to papule with IRR = 0.50, nodule and lupoid, respectively, as IRR = 0.72 and IRR = 0.51 compared to papule) had a significant effect on the mean number of dermal lesions (p < .05). Also, our results showed that among four models used, the ZINB model represented a better performance to determine the associated probable factors about the number of dermal lesions in ACL patients. Moreover, there was a direct association between age and number of dermal lesions; in addition, duration of lesion, type of lesion and location of lesion had a significant effect on the number of dermal lesions. Therefore, a comprehensive planning is necessary for controlling and reducing the number of dermal lesions.

Male predominance in reported Visceral Leishmaniasis cases: Nature or nurture? A comparison of population-based with health facility-reported data

Background

Bangladesh, India, and Nepal aim for the elimination of Visceral Leishmaniasis (VL), a systemic parasitic infectious disease, as a public health problem by 2020. For decades, male patients have comprised the majority of reported VL cases in this region. By comparing this reported VL sex ratio to the one observed in population-based studies conducted in the Indian subcontinent, we tested the working hypothesis that mainly socio-cultural gender differences in healthcare-seeking behavior explain this gender imbalance.

Methodology/Principal findings

We compared the observed sex ratio of male versus female among all VL cases reported by the health system in Nepal and in the two most endemic states in India with that observed in population-based cohort studies in India and Nepal. Also, we assessed male sex as a potential risk factor for seroprevalence at baseline, seroconversion, and VL incidence in the same population-based data. The male/female ratio among VL cases reported by the health systems was 1.40 (95% CI 1.37–1.43). In the population cohort data, the age- and study site-adjusted male to female risk ratio was 1.27 (95% CI 1.08–1.51). Also, males had a 19% higher chance of being seropositive at baseline in the population surveys (RR 1.19; 95% CI 1.11–1.27), while we observed no significant difference in seroconversion rate between both sexes at the DAT cut-off titer defined as the primary endpoint.

Conclusions/Significance

Our population-based data show that male sex is a risk factor for VL, and not only as a socio-cultural determinant. Biological sex-related differences likely play an important role in the pathogenesis of this disease.

Visceral Leishmaniasis (VL) is a parasitic disease that is lethal if not treated timely and mainly affects impoverished populations. Bangladesh, India, and Nepal have targeted the elimination of this disease as a public health problem by 2020. The majority of VL patients attending the health services are male, and this is usually attributed to unequal access to health care for men and women in this sociocultural context. We analyzed two large datasets obtained in population surveillance projects, including regular door-to-door screening for VL, in India and Nepal. Thereby we minimized any potential differences in access to health care between both sexes, as every suspect VL case occurring in the community received a full diagnostic work-up, and the research project facilitated transport to treatment centers if needed. By comparing the observed sex ratio in the health services records with those of the population surveillance records, we aimed to reach meaningful conclusions about the pathway through which male gender exerts its leverage for increasing VL risk: socio-cultural determinants blocking women from accessing care (nurture) or biological factors (nature) making men more vulnerable to VL. Because in the population-based age adjusted-data, male VL cases were significantly more frequent than female, our findings strongly suggest that in the Indian subcontinent, biological differences between men and women play a more critical role in the pathogenesis of VL than previously assumed, and the observed male predominance in VL cases in health services cannot be explained by socio-cultural factors only. Moreover, data show that above the age of 14 years, males are seropositive more often than females and are at higher risk to develop VL disease.

Cutaneous and mucocutaneous leishmaniasis: experience of a Mediterranean hospital

Background

Leishmaniasis, considered by the World Health Organization as one of the most important tropical diseases, is endemic in the Mediterranean Basin. The aim of this study was to evaluate epidemiological and clinical characteristics of cutaneous (CL) and mucocutaneous leishmaniasis (MCL) in La Fe University Hospital, Valencia, Spain. The particular focus was on diagnosis techniques and clinical differences according to the immunological status of the patients.

Methods

An eleven-year retrospective observational study of CL and MCL episodes at the hospital was performed. Epidemiological, clinical and therapeutic variables of each case, together with the microbiological and anatomopathological diagnosis, were analyzed.

Results

A total of 42 patients were included, 30 of them were male and 28 were immunocompetent. Most of the cases (36/42) were diagnosed in the last 5 years (2013–2017). The incidence of CL and MCL increased from 3.6/100,000 (2006–2012) to 13.58/100,000 (2013–2017). The majority of the patients (37/42) exhibited CL, in 30 cases as single lesions (30/37). Ulcerative lesions were more common in immunosuppressed patients (13/14) than in immunocompetent patients (20/28), (P = 0.2302). The length of lesion presence before diagnosis was 7.36 ± 6.72 months in immunocompetent patients and 8.79 ± 6.9 months in immunosuppressed patients (P = 0.1863). Leishmania DNA detection (92.3%) was the most sensitive diagnostic technique followed by Giemsa stain (65%) and histopathological examination (53.8%). Twelve patients (12/42) had close contact with dogs or were living near to kennels, and 10 of them did not present underlying conditions. Intralesional glucantime (21/42) and liposomal amphotericin B (7/42) were the most common treatments administered in monotherapy. All patients evolved successfully and no relapse was reported.

Conclusions

Some interesting clinical and epidemiological differences were found in our series between immunocompetent and immunosuppressed patients. Future studies can take these results further especially by studying patients with biological therapy. Skin biopsies combining NAAT with histological techniques are the most productive techniques for CL or MCL diagnosis.

A Clinicoepidemiological Study of Pediatric Cutaneous Leishmaniasis in Sinjar Province, Iraq

Cutaneous leishmaniasis (CL) is a major health problem worldwide. Although CL is a common disease among children, treatment regimens for the pediatric age group are based on extrapolation of efficacy data in adults. The present study aimed to evaluate the treatment outcome of CL in preschool-age children and the factors influencing the outcome. Two hundred ninety-four children were diagnosed with CL between December 2018 and March 2019 in Sinjar Province, Iraq. All patients were treated with intralesional injections of sodium stibogluconate and followed up for 3 months after the completion of treatment. The treatment success rate was 99% (291/294). A statistically significant association was found between the number of doses per lesion and the number of lesions (P = 0.002; CI = 0.066-0.2875). No association was found between the number of lesions, age, gender, or the presence of livestock and the treatment outcome. In conclusion, treatment success rate was high with the use of intralesional injection of sodium stibogluconate. A significant association was found between the number of lesions and the number of doses. Further studies are required to assess the treatment outcome indicators, including the genotype of leishmania.

Demographical and population dynamics impact on public health of cutaneous Leishmaniasis in Al-Madinah Almonawra, Saudi Arabia

Background

A cross-sectional study conducted in Al-Madinah Almonawra in KSA held during the period from March 2014–March 2015.

Aim of the study

This study aimed at analyzing the effect of population dynamics on the current situation of cutaneous leishmaniasis in Al-Madinah Almonawarah area, a holy city that attracts millions of muslims annually.

Methodology

Epidemiological and clinical data were collected by especial questionnaire and laboratory specimens were collected using skin scraping and needle aspiration. Staining and direct microscopy were done. LST was conducted. Analysis was done using SPSS program.

Results

The study included 164 patients, all of them were men. Saudi nationality comprised around 20% of the study group, the majority were Egyptians, 26.2%, followed by Pakistani, 21.3%.

Conclusion

The presence of non-Saudi nationality as foreign workers, immigrants and refugees has worsened the current situation of the disease.

A clinical study of cutaneous leishmaniasis in a new focus in the Kurdistan region, Iraq

Leishmaniasis is caused by protozoan parasites of the genus Leishmania and is a major health problem in various parts of the world. Cutaneous leishmaniasis (CL) occurs, among others, in unpredictable outbreaks after wars and disasters. After the last war in Iraq, the collapse of the health system led to the spread of infectious diseases, including CL. Between September 2016 and November 2017, all patients with confirmed CL having one or more skin lesion(s) were referred to a regional health center in Musol City within the Rabeea District. During this period, 1539 patients visited the clinic. A total of 190 patients were excluded from the study because of poor follow-up. The treatment success rate was 97.7% (1319/1349). Statistically significant associations were found between number of lesions and treatment failure (p = 0.0018; OR = 1.4430; CI = 1.1466–1.8161), number of doses and number of lesions (Pearson’s correlation coefficient = 0.095; p = 0.001), and the lack of municipality services and number of doses used for the treatment (p = 0.008; OR = 1.0629; CI = 1.0158–1.1122). To conclude, the highest number of patients with CL in the city of Musol was recorded after the war in Iraq. The treatment success rate was high, which reflected the strict treatment and follow-up program. An urgent plan is needed to stop the spread of infection.

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.