Acute Cutaneous Leishmaniasis Research Articles

Global burden of cutaneous leishmaniasis: a cross-sectional analysis from the Global Burden of Disease Study 2013

High-quality epidemiological studies evaluating the burden of cutaneous leishmaniasis worldwide are lacking. We compared the burden of cutaneous leishmaniasis in each country to the overall global burden and assessed the equality of cutaneous leishmaniasis burden across different countries and regions. Data were extracted from scientific literature, hospital sources, country reports, and WHO sources on the prevalence of sequalae of both acute and chronic cutaneous leishmaniasis. Prevalence data were combined with a disability weight to yield years lived with disability. Disability-adjusted life-years (DALYs) are a sum of the years lived with disability and years of life lost (or mortality, assumed to be zero). We compared DALYs due to cutaneous leishmaniasis for 152 countries using standard Z score analysis with Bonferroni correction (p<0·003) and generation of Lorenz curves with a Gini coefficient. In 2013, the global mean age-standardised DALYs for cutaneous leishmaniasis was 0·58 per 100 000 people. Nine countries had significantly greater DALYs from cutaneous leishmaniasis than the mean: Afghanistan (87·0), Sudan (20·2), Syria (9·2), Yemen (6·2), Iraq (6·0), Burkina Faso (4·8), Bolivia (4·6), Haiti (4·1), and Peru (4·0). The Gini coefficient was 0·89. Andean Latin America, North Africa and Middle East, western sub-Saharan Africa, and south Asia had the highest DALYs from cutaneous leishmaniasis. Among males, Palestine had the highest incidence rates (616·2 cases per 100 000 people) followed by Afghanistan (566·4), Syria (357·1), and Nicaragua (354·8). Among females, Afghanistan had the highest incidence rates (623·9) followed by Syria (406·3), Palestine (222·1), and Nicaragua (180·8). Similar proportions of males and females had cutaneous leishmaniasis in most countries with a high incidence. The burden from cutaneous leishmaniasis mainly falls on countries in Africa and the Middle East. Global and national data on the burden of cutaneous leishmaniasis disease are pivotal to promote field studies and initiate behavioural change. Bill & Melinda Gates Foundation.

Treatment of Acute Cutaneous Leishmaniasis by Oral Zinc Sulfate and Oral Ketocanazole Singly and in Combination

Background: Cutaneous Leishmaniasis (CL) is an endemic disease in many countries and caused by different species of Leishmania parasite. It results in a deformed scar after a relatively long period. Many therapies have been tried in treatment of this disease. Objective: To compare the effect of oral zinc sulfate and oral ketoconazole singly and in combination in the treatment of acute cutaneous leishmaniasis. Patients and Methods: This single, blinded, therapeutic, controlled study was conducted in the Department of Dermatology, Baghdad Teaching Hospital, Baghdad, Iraq, during the period, January 2015 to July 2015. Seventy-five patients with acute CL were enrolled in this study. The total numbers of lesions were 327, and the duration of lesions ranged from 4 to 12 (6.9 ± 0.7) weeks. The diagnosis was confirmed by smear and histopathology. Patients were divided into three groups: 24 patients in Group A were treated with oral zinc sulfate capsules 10 mg/kg/day for 6 weeks; 24 patients in Group B were treated with ketoconazole tablets 200 mg twice daily for 6 weeks and 27 patients in Group C were treated orally with a combination of zinc sulfate and ketoconazole for 6 weeks. All patients were seen regularly every 2 weeks for 6 weeks of treatment period, then monthly for the next three months as follow up period. Healing of the lesions was assessed by using Sharquie’s modified Leishmania score to assess the objective response to the topical or systemic therapy. Results：After six weeks, 75 patients have completed the treatment, 24patients received zinc sulfate capsule, 24 patients received oral ketoconazole and 27 patients received a combination of both treatments. The cure rate was (60%) in the group receiving oral zinc sulfate capsuleand (50%) in the one receiving oral ketoconazole tablet (P = 0.146) and (96%) in the combination group (P ? 0.04). Conclusion: The combination therapy using oral zinc sulfate and oral ketoconazole gave a high cure rate. The combination therapy is a new mode of therapy as both drugs act in a synergistic way.

Epidemiological study on acute cutaneous leishmaniasis in Morocco

ObjectiveTo describe and compare the epidemiological features of anthroponotic cutaneous leishmaniasis (ACL) caused by Leishmania tropica, and zoonotic cutaneous leishmaniasis (ZCL) due to Leishmania major in Morocco. MethodsWe performed a retrospective study of ZCL and ACL cases reported during the last ten years in Morocco (2004–2013). Epidemiological data were analyzed by using Pearson's correlation method as well as Tukey test and digital maps were produced for incidence repartition calculated by using ArcMap GIS version 10. ResultsA total of 41656 cases of cutaneous leishmaniasis were notified between 2004 and 2013 in Morocco. The mean incidence was 139 cases/100000 population/10 years and it was significantly higher in 2010. In the spatial context, ACL form was the most common in Morocco, while ZCL was the most important in terms of the number of reported cases. For both forms, the highest incidence occurred in females and children (0–14 years). When analyzed according to the number of cases in each province, Errachidia (8728 cases) and Azilal (3523 cases) were the most affected by ZCL and ACL, respectively, while the highest incidence was noted in Zagora (231 cases/100000 population/10 years) and in Chichaoua (97 cases/100000 population/10 years), for ZCL and ACL, respectively. Maps of incidence repartition were performed to identify the risk area of ZCL and ACL. ConclusionsZCL and ACL are still major health problems in Morocco. We highlight the spatiotemporal change of cutaneous leishmaniasis incidence through the country during the last ten years and we underline the correlation between ZCL incidence and the percentage of rural population in Morocco.

Prevalence and epidemiologic profile of acute cutaneous leishmaniasis in an endemic focus, Southwestern Iran

ObjectiveTo evaluate the cutaneous leishmaniasis prevalence in Shadegan County, Iran, during 2007–2009. MethodsThis is a descriptive research which concentrates on the 100 patients who we referred to the Shadegan Health Center. The disease was diagnosed based on clinical exam and microscopic observation of the parasites in the lesion site. The patients' data were recorded. The statistics have examined the various epidemiological aspects of the disease by considering descriptive indices such as gender, age, occupation, month and seasonal distribution, number and site of the lesions. Information analysis was performed using SPSS software. ResultsOverall, 100 cases consisting of 32 females (32%) and 68 males (68%) were examined for the presence of active ulcers. Most of the infection was in age group 11–20 years (31%) and the lowest in 31–40 years group (7%). Most of the active ulcers were on the feet (42%). The majority (47%) had one lesion. Most of the cases (42%) had occurred during 2007. All cases were observed in the rural areas. ConclusionsThis study showed that the male sex and people under 20 years of age are mostly at risk. Therefore, education for groups at risk is very important.

Comparison between intralesional injection of zinc sulfate 2% solution and intralesional meglumine antimoniate in the treatment of acute old world dry type cutaneous leishmaniasis: a randomized double-blind clinical trial.

Zinc sulfate (ZS) has been used for the treatment of acute cutaneous leishmaniasis (CL) in both forms of in vivo and in vitro recently. The aim of the present study was to compare the efficacy of intralesional injection of ZS 2% solution with intralesional glucantime in the treatment of acute CL. In this double-blind randomized clinical trial, 80 cases with acute old world dry type CL were enrolled in the study. The treatment protocol in the first group consisted of intralesional injection of ZS 2% vials once a week for 10weeks or sooner in case of complete resolution of the lesions. In the second group, intralesional glucantime once a week for 10weeks or sooner in case of complete resolution of the lesions were used. In both groups cryotherapy was performed once every other week for 10weeks. In ZS versus second group, partial and complete clinical response was observed with fewer injections although this difference was not statistically significant. In addition, we found that the trend of treatment in second group was faster but again it was not significant [partial treatment: hazard ratio (HR) 1.4, 95% CI 0.7-2.9; complete treatment: HR 1.3, 95% CI 0.6-2.8]. The results of this study showed that the intralesional injection of ZS 2% solution was as effective as glucantime on the healing of the acute old world dry type CL.

Comparison Between Intralesional Meglumine Antimoniate and Combination of Trichloroacetic Acid 50% and Intralesional Meglumine Antimoniate in the Treatment of Acute Cutaneous Leishmaniasis: A Randomized Clinical Trial

Background: Cutaneous leishmaniasis (CL) is an endemic disease in Iran. Pentavalent antimonials including meglumine antimoniate (MA) are still the gold standard treatment. Trichloroacetic acid (TCA) is used in treatment of acne scar, photodamaged skin, and some other dermatologic diseases. Considering the TCA potential to induce collagen synthesis and its efficacy in the treatment of papular CL lesions, this study was conducted to assess the efficacy of combined intralesional MA and TCA in comparison to MA alone in treatment of CL. Objectives: This study was designed to compare the efficacy of the combination therapy of intralesional MA and TCA with intralesional MA alone in the treatment of CL. Patients and Methods: A total of 200 patients with confirmed CL were selected and randomized into two treatment groups. Both groups were treated with intralesional injection of MA twice a week until complete resolution of the lesions or end of the eighth week. In combination therapy group, TCA was applied to the lesions fortnightly for eight weeks. Data were analyzed statistically using chi-square, student t, and Kaplan-Meier tests. Results: Complete resolution of the lesions was achieved in 79.2% of patients treated with MA and 85.7% of patients receiving combination therapy (P > 0.05). There was a significant difference in time to achieve the complete resolution between the groups with an accelerated resolution rate in the combination therapy group (P < 0.05). Conclusions: According to the results of this study, combination therapy with intralesional MA and TCA 50% could accelerated the resolution of CL lesions with no significant difference in complete resolution rate in comparison to the patients treated with intralesional MA alone. Topical application of TCA 50% as an adjuvant therapy might have some advantages in decreasinge the resolution time of the lesions in patients with CL.

Concentrated Extracts of Cassia fistula Versus Intralesional Injection of Meglumine Antimoniate in Treatment of Acute Cutaneous Leishmaniasis

Background: Cutaneous leishmaniasis is an endemic disease in Iran. Although there are several treatment modalities for this disease, pentavalent antimonials are still considered as first line agents. There have been several reports concerning the effectiveness of Cassia fistula plant for leishmaniasis treatment. Objectives: This study was designed to assess the effectiveness of concentrated boiled and hydroalcoholic extracts of C. fistula on leishmaniasis lesions in comparison with intralesional injection of meglumine antimoniate (MA). Patients and Methods: In this randomized parallel clinical trial, 165 patients, 6-60 years old, with positive results of leishmaniasis smear tests were selected amongst the patients referred to the Skin Diseases and Leishmaniasis Research Center (SDLRC), Isfahan, Iran. They were randomly allocated to three groups for treatment with concentrated boiled extract of C. fistula, hydroalcoholic extract of C. fistula, and intralesional injection of MA. Patients were assessed at weeks one, two, three, four, and 16. Results of the treatment were reported as complete, partial, and no improvement. Results: complete resolution of the lesions at week 16 was observed in 22 (40%), 20 (36.4%), and 36 (65.5%) patients, in those treated with concentrated boiled extract of C. fistula, hydroalcoholic extract of C. fistula, and intralesional injection of MA, respectively. The efficacy of intralesional injection of MA was significantly more than concentrated boiled extract of the C. fistula application (P = 0.02). In addition, the efficacy of intralesional injection of MA was significantly more than hydroalcoholic extract of the C. fistula application (P = 0.005). There was no significant difference between the efficacy of concentrated boiled extract and the hydroalcoholic extract of the C. fistula (P = 0.61). Conclusions: Our study showed that almost 40% of the patients treated with C. fistula achieved complete resolution of the lesions. We recommend further evaluation of the effect of combined intralesional injection of MA and topical therapy with this plant, to assess the accelerating resolution of leishmaniasis lesions, and possibly decrease the applied dose of MA.

The efficacy of Achilles millefolium topical gel along with intralesional injection of glucantime in the treatment of acute cutaneous leishmaniasis major.

Background:Leishmaniasis is still one of the endemic parasitic infections in many countries comprising Iran. During the past decades, several medical and surgical approaches have been applied and studied to achieve the best option to treat the cutaneous leishmaniasis in Iran and the world. This study was carried out to evaluate the effect of topical Achilles millefolium in conjunction with intralesional glucantime on acute cutaneous leishmanial lesions.Materials and Methods:sixty patients with confirmed acute cutaneous leishmaniasis were recruited in the study. Patients were randomly allocated into two groups to receive twice daily topical gel of Achilles millefolium 5% (containing 5% poly phenol) (group A) or placebo (group B) for four weeks along with weekly injection of intralesional Glucantime.Results:There was no significant difference between the two groups according to age, gender, and duration of the disease. Also, there was no significant difference in complete and relative cure rates between the two groups (P = 0.35) using Visual Analog Scale (VAS). Application site reactions were occurred in 12 patients including redness in 8 cases in group-A and 2 cases in group-B, severe itching in one case in group-A and increasing wound secretion in another case in group-A (P = 0.014).Conclusions:Given the result of the present study, there is no significant difference in cure rates of lesions between yarrow and placebo topical gels as an adjuvant drugs with intralesional glucantime in treatment of acute cutaneous leishmanial lesions.

Acute New World cutaneous leishmaniasis presenting as tuberculoid granulomatous dermatitis

Acute primary cutaneous leishmaniasis typically presents microscopically with a lymphohistiocytic infiltrate containing admixed plasma cells, parasitized macrophages and abundant organisms. Tuberculoid granulomatous changes may occur in the later phases of primary infection. A 23-year-old male presented 1 month after visiting Peru with classic clinical findings of acute primary cutaneous leishmaniasis, while histopathology showed a tuberculoid granulomatous process that lacked any organisms in hematoxylin-eosin and fungal stains. Polymerase chain reaction (PCR) analysis and tissue cultures confirmed the diagnosis of cutaneous leishmaniasis with Leishmania (Viannia) panamensis infection. A pauci-organism tuberculoid granulomatous process may uncommonly be the presenting histopathology in the acute infectious phase of cutaneous leishmaniasis. Clinicians and dermatopathologists should be aware of this atypical presentation, which may cause diagnostic confusion and delay proper treatment. PCR testing should be employed in cases with high clinical suspicion when histopathology is not definitive.

Comparison of intralesional two percent zinc sulfate and glucantime injection in treatment of acute cutaneous leishmaniasis

Introduction:Cutaneous leishmaniasis is an endemic disease in developing countries caused by different species of leishmania parasite, and if left untreated, it will result in a deformed scar after a relatively long period. Although various systemic and topical treatments have been proposed for leishmaniasis, pentavalent Antimony compounds remain the first-line treatment for it. Considering the cases with treatment failure, potential side effects and reluctance of patients to receive the drug, there are continuing efforts to find better treatment alternatives.Aim:Comparison of the effect of intralesional 2% zinc sulfate injection with Glucantime in treatment of acute cutaneous leishmaniasis.Materials and Methods:In this clinical trial, 45 patients with clinical diagnosis of cutaneous leishmaniasis and positive direct smear for leishman body were treated by intralesional injection of either 2% zinc sulfate or Glucantime. After simple randomization, in one group the patients were treated with 2 bouts of intralesional 2% zinc sulfate with a 2-week interval, and in the other group they were treated with 6 weekly bouts of intralesional Glucantime. The patients were monitored in two week intervals for 8 weeks. Healing of the lesions was evaluated clinically and by direct smear, and the data were analyzed using SPSS (11.5) software, t-Student, Mann-Whitney and Analysis of covariance (ANCOVA) statistical tests.Findings:In the end of study, 34 patients completed the study, 10 of whom received intralesional Glucantime and 24 of whom received intralesional 2% zinc sulfate. The healing rate after 8 weeks was 80% in the group receiving intralesional Glucantime and 33.3% in the one receiving 2% zinc sulfate (P=0.009).Conclusion:Based on the results of this study, intralesional injection of 2% zinc sulfate was less effective in treatment of cutaneous leishmaniasis than intralesional Glucantime.

Chronic cutaneous leishmaniasis, a great mimicker with various clinical presentations: 12 years experience from Aleppo

Cutaneous leishmaniasis (CL) has been an endemic disease in Aleppo, Syria for many decades. During the past 12 years, there was a clear increase in the overall incidence of the disease in the region. Treatment using intralesional method of antimonial compounds became ineffective in a considerable proportion of cases and more patients developed the chronic form of the disease. To categorize chronic cutaneous leishmaniasis (CCL) into different subtypes that mimic a wide spectrum of skin diseases, and to analyse the cause of this increase in the incidence of the disease as a whole and of the chronic type in particular. A total number of 6200 patients with CL were seen in our centre, among which 1880 were initially diagnosed with CCL. Inclusion criteria for CCL included CL for more than 1 year. The diagnosis of CCL was made based on the clinical presentation and a positive Giemsa smear test. Biopsies were performed whenever the Giemsa smear was negative. Patients who had immunosuppression due to a medical condition or intake of immunosuppressive medications were excluded. Of 1880 patients, 1750 patients fit the inclusion criteria. Based on the lesion morphology, three different types of CCL were defined, among which five subtypes were observed based on clinical pattern and distribution of lesions. The two most common types of CCL were the papulonodular and plaque forms. Around 80% of all CCL cases occurred in individuals under 16 years of age and the most common location was the face (88.6% of cases). CCL due to Leishmania tropica can mimic many other dermatological conditions which might lead to a delay in making the correct diagnosis resulting in increased resistance to treatment. We have illustrated eight different clinical presentations of CCL and their differential diagnoses to make physicians more aware of the atypical presentations of CCL. A new treatment plan is suggested for the high-risk group of acute cutaneous leishmaniasis patients to decrease the likelihood of progressing to chronicity.

The interplay betweenLeishmaniapromastigotes and human Natural Killer cellsin vitroleads to direct lysis ofLeishmaniaby NK cells and modulation of NK cell activity byLeishmaniapromastigotes

NK cells represent one of the first lines of defence in the immune reaction after invasion of Leishmania parasites. Depletion of mouse natural killer (NK) cells dramatically enhances susceptibility of normally resistant mice. In this study we evaluated the fate of NK cells and parasites after contact formation. The hydrophilic fluorescent dye CMFDA (chloro-methylfluorescin diacetate) that allows analysis of cytotoxicity in flow cytometry and microscopy was used. Furthermore, these findings were confirmed with scanning and transmission electron microscopy. Direct contact points were found between Leishmania promastigotes and naïve human NK cells. These contacts were associated with transfer of cytosol by membrane bridges and cytotoxicity of NK cells against Leishmania. However, in contrast to other target cells which allow repeated exocytosis of lytic granules, contact with Leishmania causes immediate destruction of NK cells in a non-apoptotic way. Our results give a reasonable explanation for ex vivo observations of reduced NK cell numbers and impaired NK response in patients with acute cutaneous leishmaniasis. Animal models have clearly shown that NK cells play a key role in the induction and direction of the immune response. Thus inhibition of NK cells at the onset of infection would be advantageous for the survival of the parasite.

Systemic Meglumine Antimoniate in Acute Cutaneous Leishmaniasis: Children versus Adults

Some studies showed that children have a lower response to systemic use of pentavalent antimoniate than adults. We aimed to evaluate the response rate to Glucantime therapy in children and compare it with adults. One hundred and twelve patients with acute cutaneous leishmaniasis: (ACL) were divided into two equal groups of adults (> 15 yrs) and children (≤ 15 yrs). They received meglumine antimoniate; 20 mg/kg/day for 20 days, their improvement rate was evaluated 20 and 45 days after treatment. Per-protocol analysis showed a significantly lower response in the children group 20 and 45 days after initiation of the treatment (P = 0.0001, 95% confidence interval [CI] = 0.190 [0.079-0.456]/P = 0.0051, 95% CI = 0.317 [0.140-0.717], respectively). Moreover, after intention-to-treat analysis, the same results were seen in the younger group 20 and 45 days after treatment (P = 0.0003, 95% CI = 0.228 [0.098-0.528]/P = 0.0132, 95% CI = 0.382 [0.177-0.825], respectively). According to our results, systemic Glucantime has lower efficacy in treating ACL in children than adults.

Tropical medicine rounds: Treatment of acute cutaneous leishmaniasis with intralesional injection of meglumine antimoniate: comparison of conventional technique with mesotherapy gun

AbstractBackground The gold standard treatment of Old World leishmaniasis, a common tropical parasitic infestation, is intralesional meglumine antimoniate injection. Mesotherapy is a new minimally invasive method of administration of variable substances to the skin.Objective Comparison of the efficacy and adverse effects of treatment of leishmaniasis with intralesional injection of meglumine antimoniate using conventional method and mesotherapy method.Patients and methods Eighty‐five patients with proven leishmaniasis were recruited and randomly treated by one of the two methods, either by conventional injection or by mesotherapy administration weekly. Lesion characteristics were evaluated at every treatment session as well as 1 week, 1 month and 3 months after cessation of treatment.Results The improvement in lesions was similar in both groups, while it was noted sooner in mesotherapy group with less amount of drug usage (P = 0.005 and 0.016 respectively). Also, patients treated with mesotherapy experienced less pain severity (P = 0.005).Conclusion Mesotherapy is a safe and effective method of meglumine antimoniate injection for the treatment of cutaneous leishmaniasis and is less painful.

Lupoid leishmaniasis due to Leishmania major with remaining large scars: report of 2 cases

]. It is a chronic condition that typically fol-lows acute cutaneous leishmaniasis infection. In this clinical form, 1 to 2 years after healing of the acute lesion, new papules and nodules appear at the margin of the remaining scar. The papules have a granulomatous, lupoid appearance and are often associated with scaling. They characteristically present at the margin of the scarred area. Less commonly lesions may present months or years after the acute lesion has healed [

EXTENSOR TENDON RUPTURE DUE TO CUTANEOUS LEICHMANIASIS: A CASE REPORT

Acute cutaneous leishmaniasis is a parasitic infectious disease prevalent in tropical areas. Most doctors in non-endemic countries are not familiar with this disease. Spontaneous tendon ruptures occurring by different mechanisms have been described in the literature but a tendon rupture caused by a skin ulcer secondary to a parasitic infection has not been reported before. In this article clinical and diagnostic features of cutaneous leishmaniasis are reviewed and a case with spontaneous extensor tendon rupture due to cutaneous leishmaniasis is presented.

Intralesional Regulatory T-Cell Suppressive Function during Human Acute and Chronic Cutaneous Leishmaniasis Due to Leishmania guyanensis

The levels of regulatory T cells (Treg cells), analyzed by Foxp3 mRNA expression, were determined in lesions from patients with acute cutaneous leishmaniasis (ACL) and chronic cutaneous leishmaniasis (CCL). We demonstrated that Treg cells preferentially accumulate in lesions from ACL patients during the early phase of infection (lesion duration of less than 1 month). In addition, levels of Foxp3 mRNA transcripts were significantly higher in specimens from patients with CCL than in those from patients with ACL, suggesting a critical role of intralesional Treg cells in CCL. Intralesional Treg cells from both ACL and CCL patients were shown to have suppressive functions in vitro, since they inhibited the gamma interferon (IFN-gamma) produced by CD4(+) CD25(-) T cells purified from peripheral blood mononuclear cells from the same patient in response to Leishmania guyanensis stimulation. Intralesional 2,3-indoleamine dioxygenase (IDO) mRNA expression was associated with that of Foxp3, suggesting a role for IDO in the suppressive activity of intralesional Treg cells. In addition, a role, albeit minor, of interleukin-10 (IL-10) was also demonstrated, since neutralization of IL-10 produced by intralesional T cells increased IFN-gamma production by effector cells in an in vitro suppressive assay. These results confirm the role of intralesional Treg cells in the immunopathogenesis of human Leishmania infection, particularly in CCL patients.

Comparative Effect of Topical Trichloroacetic Acid and Intralesional Meglumine Antimoniate in the Treatment of Acute Cutaneous Leishmaniasis

Comparative Effect of Topical Trichloroacetic Acid and Intralesional Meglumine Antimoniate in the Treatment of Acute Cutaneous Leishmaniasis

Impairment of Alternative Macrophage Activation Delays Cutaneous Leishmaniasis in Nonhealing BALB/c Mice

Expressed on various cell types, the IL-4Ralpha is a component of both receptors for IL-4 and IL-13. Susceptibility of BALB/c mice to Leishmania major is believed to be dependent on the development of IL-4- and IL-13-producing Th2 cells, while IFN-gamma secretion by Th1 cells is related to resistance. Despite a sustained development of Th2 cells, IL-4Ralpha-deficient BALB/c mice are able to control acute cutaneous leishmaniasis, suggesting that IL-4Ralpha-bearing cells other than Th2 cells contribute to susceptibility. To analyze the contribution of the IL-4Ralpha on macrophages, recently generated macrophage/neutrophil-specific IL-4Ralpha-deficient mice on a susceptible BALB/c genetic background were infected with L. major. Strikingly, macrophage/neutrophil-specific IL-4Ralpha-deficient mice showed a significantly delayed disease progression with normal Th2 and type 2 Ab responses but improved macrophage leishmanicidal effector functions and reduced arginase activity. Together, these results suggest that alternative macrophage activation contributes to susceptibility in cutaneous leishmaniasis.

Sensitivity of leishmanin skin test in patients of acute cutaneous leishmaniasis

The leishmanin skin test (LST) is frequently used for clinical diagnosis of cutaneous leishmaniasis (CL). Although, LST is highly sensitive for CL, no definitive data exists as to how early in the disease does the test becomes positive. The study was aimed to evaluate the sensitivity of LST in early cases of CL. One hundred male patients with CL of not more than 2-weeks duration and having parasitologically proven diagnosis were enrolled in this study, carried out in a military hospital in Balochistan, Pakistan. LST was done by intradermal injection of 0.1 ml leishmanin on the volar surface of the forearm. The skin test reaction was read after 48 hours and then at 72 hours if the first reading was negative or marginal. If the initial test was negative, the LST was repeated after every 7 days until a positive reaction was produced. The total time from the onset of skin lesions until a positive LST was obtained was recorded for every patient. A positive LST was demonstrated in 78/100 patients with skin lesions of <or= 2 weeks duration, thus showing a sensitivity of 78 percent for this short duration. The sensitivity of LST increased to 94 percent and 98 percent for CL lesions of 4 and 6 weeks duration, respectively. LST is sensitive even in those CL patients who present with lesions of very recent onset. Thus the test can be employed with confidence, for the diagnosis of CL, even in early disease.