LEISHMANIASIS

 

Diagnosis, Diagnostics, Immunodiagnosis & Immunodiagnostics:

 

 

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3309.                        Enserink M.  Infectious diseases. Sand fly saliva may be key to new vaccine.  Science.  293(5532):1028, 2001 Aug 10.

3310.                        Ghosh A.  Labrecque S.  Matlashewski G. Protection against Leishmania donovani infection by DNA vaccination: increased DNA vaccination efficiency through inhibiting the cellular p53 response.  Vaccine.  19(23-24):3169-78, 2001 Apr 30.

Abstract

  DNA-vaccination holds great promise for the future of vaccine development against infectious diseases, especially in developing countries. We therefore investigated the possibility of using DNA-vaccination against Leishmania donovani infection with the A2 virulence gene and whether inhibiting the cellular p53 response could increase the effectiveness of the A2 DNA vaccine. p53, also known as the guardian of the genome, is activated following DNA transfection and has pleotropic effects on cells, which could have adverse effects on the effectiveness of DNA-vaccination. Two major observations are reported within. First, vaccination with the A2 gene induced both humoral and cellular immune responses against A2 which provided significant protection against infection with L. donovani. Second, inhibition of p53 with human papillomavirus E6 resulted in higher expression of heterologous transfected genes in vitro and more efficient DNA-vaccination in vivo. These results have important implications for DNA vaccination against leishmaniasis and potentially against other infectious diseases.

3311.                        Handman E. Leishmania virulence: it's a knock out!.  Trends in Parasitology.  17(2):60, 2001 Feb.

3312.                        Handman E. Leishmaniasis: current status of vaccine development. [Review] [157 refs]  Clinical Microbiology Reviews.  14(2):229-43, 2001 Apr

Abstract

  Leishmaniae are obligatory intracellular protozoa in mononuclear phagocytes. They cause a spectrum of diseases, ranging in severity from spontaneously healing skin lesions to fatal visceral disease. Worldwide, there are 2 million new cases each year and 1/10 of the world's population is at risk of infection. To date, there are no vaccines against leishmaniasis and control measures rely on chemotherapy to alleviate disease and on vector control to reduce transmission. However, a major vaccine development program aimed initially at cutaneous leishmaniasis is under way. Studies in animal models and humans are evaluating the potential of genetically modified live attenuated vaccines, as well as a variety of recombinant antigens or the DNA encoding them. The program also focuses on new adjuvants, including cytokines, and delivery systems to target the T helper type 1 immune responses required for the elimination of this intracellular organism. The availability, in the near future, of the DNA sequences of the human and Leishmania genomes will extend the vaccine program. New vaccine candidates such as parasite virulence factors will be identified. Host susceptibility genes will be mapped to allow the vaccine to be targeted to the population most in need of protection. [References: 157]

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3313.                        No Abstract

 

3314.                        Kumar PV.  Moosavi A.  Karimi M.  Safaei A.  Noorani H.  Abdollahi B.  Bedayat GR. Subclassification of localized Leishmania lymphadenitis in fine needle aspiration smears. Acta Cytologica.  45(4):547-54, 2001 Jul-Aug.

Abstract

  OBJECTIVE: To describe the cytologic findings of localized Leishmania lymphadenitis and discuss the differential diagnosis. STUDY DESIGN: The study group consisted of 133 cases. All of them were diagnosed by fine needle aspiration (FNA) study. The ages ranged between 3 and 80 years, 102 were male and 31 female. Seventy lymph nodes were excised. RESULTS: The FNA smears revealed a polymorphic population of cells composed of lymphocytes, histiocytes, giant cells, abnormal plasma cells and tingible body macrophages. Leishman-Donovan (LD) bodies were identified in all cases, but their number differed from case to case. Granulomas, dendritic cells, mast cells and lymphoglandular bodies were identified in a substantial number of cases. Depending upon the presence of characteristic cytologic findings, the cases were divided into five major groups: acute inflammation with giant cells, histiocytic granulomas, epithelioid cell granulomas, plasma cell type and mixed histioplasmacytic type. CONCLUSION: Leishmaniasis is an uncommon cause of cervical lymphadenitis but should be considered in the differential diagnosis of unexplained lymphadenopathy in endemic countries. Demonstration of LD bodies is necessary for the diagnosis of this self-limited condition, for which no treatment is required.

3315.                         Martin-Sanchez J.  Lopez-Lopez MC.  Acedo-Sanchez C.  Castro-Fajardo JJ.  Pineda JA.  Morillas-Marquez F. Diagnosis of infections with Leishmania infantum using PCR-ELISA. Parasitology.  122(Pt 6):607-15, 2001 Jun.

Abstract

  On the basis of partial amplification of a cloned fragment of kDNA of Leishmania infantum which is specific for this species, we developed a PCR-ELISA technique which avoids the problems associated with classical diagnostic techniques. This technique was tested on 33 L. infantum strains from 19 different zymodemes, which were recognized equally. It was also used on human and canine clinical samples. PCR-ELISA has a higher sensitivity than the other techniques used (IFAT, parasite cultures, optical microscopy of stained samples) and permits detection of a minimum of 0.1 promastigotes or 1 fg of genomic DNA. PCR-ELISA can be used to diagnose human cutaneous leishmaniasis using material obtained by scraping the lesion margin, and human visceral leishmaniasis in HIV(+) individuals and canine leishmaniasis with peripheral blood samples. The presence of L. infantum in dogs with low antibody titres with IFAT technique (20 and 40) was demonstrated indicating that seroprevalence data from epidemiological studies underestimate the true rates of infection.

3316.                        Moore E.  O'Flaherty D.  Heuvelmans H.  Seaman J.  Veeken H.  de Wit S.  Davidson RN. Comparison of generic and proprietary sodium stibogluconate for the treatment of visceral leishmaniasis in Kenya. Bulletin of the World Health Organization.  79(5):388-93, 2001.

Abstract

  OBJECTIVE: To compare the use of generic and proprietary sodium stibogluconate for the treatment of visceral leishmaniasis (kala-azar). METHODS: A total of 102 patients with confirmed kala-azar were treated in a mission hospital in West Pokot region, Kenya, with sodium stibogluconate (20 mg/kg/day for 30 days)--either as Pentostam (PSM) or generic sodium stibogluconate (SSG); 51 patients were allocated alternately to each treatment group. FINDINGS: There were no significant differences in baseline demographic characteristics or disease severity, or in events during treatment. There were 3 deaths in the PSM group and 1 in the SSG group; 2 patients defaulted in each group. Only 1 out of 80 test-of-cure splenic aspirates was positive for Leishmania spp.; this patient was in the SSG group. Follow-up after > or = 6 months showed that 6 out of 58 patients had relapsed, 5 in the SSG group and 1 in the PSM group. No outcome variable was significantly different between the two groups. CONCLUSION: The availability of cheaper generic sodium stibogluconate, subject to rigid quality controls, now makes it possible for the health authorities in kala-azar endemic areas to provide treatment to many more patients in Africa.

3317.                         Rajasekariah GH.  Ryan JR.  Hillier SR.  Yi LP.  Stiteler JM.  Cui L.  Smithyman AM.  Martin SK. Optimisation of an ELISA for the serodiagnosis of visceral leishmaniasis using in vitro derived promastigote antigens.  Journal of Immunological Methods.  252(1-2):105-19, 2001 Jun 1.

Abstract

  An antibody detection ELISA was developed for diagnosis of visceral leishmaniasis. Antigens released by Leishmania donovani promastigotes into a protein-free medium were used. SDS-PAGE analysis has indicated that Ld-ESM contain several protein antigens. Titration and chequer-board analyses were performed to optimise the assay protocol. Optimal results were obtained when antigen (50 microg/ml) was coated with PBS-methyl glyoxal buffer, and wells blocked with 0.5% casein. A serum dilution of 1:500 in antigen-coated wells, blocked with 0.5% casein, generated lowest absorbance with Ref-ve sera and higher absorbance with Ref+ve sera. All steps of the ELISA were performed at room temperature. The S/N ratio, the differential absorbance between the negative sample vs. the test or Ref+ve sample, was used to quantify the specific antigen and antibody reactions. An anti-human monoclonal antibody conjugated with HRP (MAb-conjugate) outperformed a commercially available anti-human polyclonal antibody conjugate (PAb-conjugate). The MAb-conjugate gave minimal background reactions with endemic sera. Optimised final assay steps mentioned below were used to evaluate sera samples from field trials. ELISA wells were coated with 50 microg/ml Ld-ESM mixed in PBS-methyl glyoxal overnight, and after removing the antigen, blocked with 0.5% casein for 1 h at RT. Patient sera along with control sera, diluted to 1:500 in PBS/T, were reacted for 1 h at RT. After washing the plate with PBS/T, wells were reacted with MAb-conjugate for 40 min at RT, and after washing, binding of antibodies was visualized by using TMB as a chromogen substrate. The relative specific binding was quantified by the S/N ratio. A batch of n=22 endemic sera from North Africa were evaluated and resulted with 100% specificity and sensitivity, 99.99% PPV and 95.45% NPV. The specificity and sensitivity of this assay will be further evaluated in planned retrospective and prospective multi-site trials.

3318.                        Rathi S.  Post-kala-azar dermal leishmaniasis with an atypical presentation.  Journal of Dermatology.  28(6):341-2, 2001 Jun.

3319.                         No Abstract

3320.                        Romero GA.  Guerra MV.  Paes MG.  Cupolillo E.  Bentin Toaldo C.  Macedo VO.  Fernandes O. Sensitivity of the polymerase chain reaction for the diagnosis of cutaneous leishmaniasis due to Leishmania (Viannia) guyanensis. Acta Tropica.  79(3):225-9, 2001 Jun 22.

Abstract

  The sensitivity of the polymerase chain reaction (PCR) in 35 consecutive outpatients with cutaneous leishmaniasis caused by Leishmania (Viannia) guyanensis was evaluated using, as gold standard, the in vitro isolation of the parasite through culture of aspirates of the cutaneous ulcers. All isolates were identified using electrophoretic enzyme analysis. Patients were mainly young males with recent onset disease without prior specific treatment. PCR was performed using DNA extracted from fresh frozen biopsies of cutaneous ulcers. The reaction used a pair of oligonucleotides that amplify the conserved region of the minicircle molecule. PCR showed 100% sensitivity (95% CI from 90.0 to 100.0). These results were similar to the visualization of amastigotes in imprint preparations of cutaneous biopsy tissue and the inoculation of biopsy material in golden hamsters. Despite the high sensitivity of the PCR, in this particular clinical setting of cutaneous leishmaniasis caused by L. (V.) guyanensis in the Brazilian Amazon, it appears that the method of choice for diagnosis should be the direct visualization of amastigotes using imprint preparations and the PCR reserved for those patients with negative imprint results.

3321.                        No Abstract

3322.                         Sotiropoulos G.  Wilbur B.  Two cases of cutaneous Leishmaniasis presenting to the emergency department as chronic ulcers. Journal of Emergency Medicine.  20(4):353-6, 2001 May.

Abstract

  With the increasing numbers of travelers and immigrants coming to the United States from tropical areas where Leishmaniasis is endemic, it is important to be familiar with its common cutaneous manifestations. Leishmaniasis is a parasitic infection caused by the obligate intracellular protozoa Leishmania and is transmitted by the bite of the sandfly. It can appear as a nonhealing lesion on exposed skin in patients and is often misdiagnosed, delaying treatment. We present two cases of patients who presented to the Emergency Department with chronic, nonhealing ulcers that were ultimately found to have Leishmaniasis.

3323.                        Yaggi HK.  Federman DG.  Cutaneous leishmaniasis in an Italian woman: case report. Connecticut Medicine.  65(6):333-7, 2001 Jun.

Abstract

  Leishmaniasis is a sandfly-borne disease caused by a protozoan. The typical lesion of cutaneous leishmaniasis first appears as an erythematous papule at the site of inoculation, increases slowly in size, develops raised borders, and eventually ulcerates. The pentavalent antimony compounds continue to be a mainstay of therapy. We describe an Italian patient with an enlarging facial plaque that was found to be caused by leishmania and discuss the toxicity associated with therapy.

3324.                        Zijlstra EE.  el-Hassan AM. Leishmaniasis in Sudan. Post kala-azar dermal leishmaniasis.  Transactions of the Royal Society of Tropical Medicine & Hygiene.  95 Suppl 1:S59-76, 2001 Apr.

Abstract

  Post kala-azar dermal leishmaniasis (PKDL) is increasingly recognized in Sudan as a complication of visceral leishmaniasis (VL), occurring in c. 55% of patients after, or during treatment of, VL. The development of PKDL seems to be restricted to parasites of the Leishmania donovani sensu stricto cluster; no particular zymodeme has been found to be associated with it. In contrast to PKDL in India, PKDL in Sudan occurs within 0-6 months after treatment for VL. The rash may be macular, maculo-papular or nodular, and spreads from the perioral area to other parts of the body, depending on grade of severity. Young children are particularly at risk of developing more severe disease. In 16% of PKDL patients, parasites can be demonstrated by microscopy in lymph node or bone marrow aspirates and, with the aid of the polymerase chain reaction (PCR), in lymph nodes of 81% of patients, possibly indicating persistent visceralized infection. Diagnosis can be made by demonstration of parasites in skin smears or biopsies in 20-30% of cases; newer techniques, using PCR with skin smears, have higher sensitivity (83%). Monoclonal antibodies against L. donovani can detect parasites in 88% of biopsies. Serological tests are of limited value. The leishmanin skin test is positive in 50-60% of cases; there is an inverse relationship between the skin test result and severity of PKDL. In differential diagnosis, miliaria rubra is the most common problem; differentiation from leprosy is the most difficult. In biopsies, hyperkeratosis, parakeratosis, acanthosis, follicular plugging and liquefaction degeneration of the basal layer may be found in the epidermis; in the dermis there are varying intensities of inflammation with scanty parasites and mainly lymphocytes; macrophages and epithelioid cells may also be found. In 20% of cases discrete granulomas may be found. After VL, the immune response shifts from a Th2-type to a mixed Th1/Th2-type. High levels of interleukin-10 in skin biopsies as well as in peripheral blood mononuclear cells and plasma in patients with VL predict the development of PKDL. Treatment is needed only for those who have severe and prolonged disease; sodium stibogluconate (20 mg/kg/d for 2 months) is usually sufficient. (Liposomal) amphotericin B is effective, whereas ketoconazole, terbinafine and itraconazole are not.

Apr 02

4101.                        Arevalo I, Ward B, Miller R, Meng TC, Najar E, Alvarez E, Matlashewski G, Llanos-Cuentas A. Successful treatment of drug-resistant cutaneous leishmaniasis in humans by use of imiquimod, an immunomodulator. Clin Infect Dis  2001 Dec 1;33(11):1847-51

 

Treatment failures for leishmaniasis with pentavalent antimonials, including meglumine antimonate, are increasingly common in many endemic areas. Imiquimod (Aldara; 3M Pharmaceuticals) is a novel immune response-activating compound, approved by the United States Food and Drug Administration, that is currently used to treat cervical warts and has been shown to activate macrophage killing of Leishmania species. Therefore, an open-label, prospective study was conducted of combined imiquimod plus meglumine antimonate therapy in 12 patients with cutaneous leishmaniasis who had previously not responded to meglumine antimonate therapy. All of the patients responded well to this combination therapy, and 90% were found to be cured at the 6-month follow-up period.

4102.                        Bourreau E, Prevot G, Gardon J, Pradinaud R, Launois P. High intralesional interleukin-10 messenger RNA expression in localized cutaneous leishmaniasis is associated with unresponsiveness to treatment. J Infect Dis  2001 Dec 15;184(12):1628-30

 

The intralesional expression of cytokines (interleukin [IL]-4, IL-13, IL-10, and interferon-gamma) was analyzed in 65 patients with localized cutaneous leishmaniasis due to Leishmania guyanensis before specific treatment with pentamidine isethionate. The local expression of IL-10 was significantly higher in patients who responded poorly to treatment than in patients whose lesions were regressing. When an IL-10 level >10 (ratio of the concentration of IL-10 [pg/microL] to that of beta-actin [pg/microL]) was used as an indicator of treatment failure, the sensitivity of this test was 78.6, and the specificity was 72.5. Thus, high intralesional expression of IL-10 might predict a poor response to conventional treatment.

 

4103.                        Bretsche PA, Ismail N, Menon JN, Power CA, Uzonna J, Wei G. Vaccination against and treatment of tuberculosis, the leishmaniases and AIDS: perspectives from basic immunology and immunity to chronic intracellular infections. Cell Mol Life Sci  2001 Nov;58(12-13):1879-96

 

The occurrence of infectious disease represents a failure of the immune system, a failure that must be prevented by effective vaccination or remedied by treatment. Vaccination against acute diseases such as smallpox and polio are very effective, due to the rapid and increased immune response of vaccinated individuals upon natural infection. In contrast, effective vaccination against intracellular pathogens that cause chronic diseases, such as the leishmaniases, tuberculosis and AIDS, has not been achieved. Clinical observations suggest cell-mediated, Th1 responses, exclusive of antibody production and the generation of Th2 cells, are optimally protective against these intracellular pathogens. Effective vaccination must ensure the generation of such a protective response. We explore here whether understanding very broad features of the regulation of the immune response can accommodate modern findings on the immunological features of these diseases, and provide a perspective within which strategies for effective vaccination and treatment can be developed.

4104.                        Dietze R, Carvalho SF, Valli LC, Berman J, Brewer T, Milhous W, Sanchez J, Schuster B, Grogl M. Phase 2 trial of WR6026, an orally administered 8-aminoquinoline, in the treatment of visceral leishmaniasis caused by Leishmania chagasi. Am J Trop Med Hyg  2001 Dec;65(6):685-9

 

There are no recognized orally administered treatments for any of the leishmaniases. The 8-aminoquinoline WR6026 is an orally administered analog of primaquine that cured 50% of patients with kala-azar in Kenya at a dose of 1 mg/kg/day for 28 days. A further phase 2, open-label, dose-escalating safety and efficacy study was performed for kala-azar in Brazil. Cure rates for Brazilian patients treated for 28 days were as follows: 1 mg/kg/day: 0 of 4 (0%); 1.5 mg/kg/day: 1 of 6 (17%); 2.0 mg/kg/day: 4 of 6 (67%); 2.5 mg/kg/day: 1 of 5 (20%); and 3.25 mg/kg/day: 0 of 1 (0%). Nephrotoxicity that was not anticipated from preclinical animal studies or from phase 1 studies was seen at 2.5 mg/kg/day in 2 patients and in the single patient administered 3.25 mg/kg/day. WR6026 demonstrated the unusual clinical features of lack of increased efficacy against Brazilian kala-azar with increased dosing above 2 mg/kg/day and toxicity that was not present in previous investigations.

4105.                        Habibi GR, Khamesipour A, McMaster WR, Mahboudi F. Cytokine gene expression in healing and non-healing cases of cutaneous leishmaniasis in response to in vitro stimulation with recombinant gp63 using semi quantitative RT-PCR. Scand J Immunol  2001 Oct;54(4):414-20

 

Objectives of this study were to test the cytokine gene expression in peripheral blood mononuclear cells (PBMCs) from cases with nonhealing and healing cutaneous leishmaniasis (CL) in response to in vitro stimulation of recombinant gp63 (rgp63) and soluble Leishmania antigen (SLA). Healing and nonhealing cases are, respectively, defined as recovered from disease and refractory to various treatments. To evaluate the type of immunological response, mRNA transcription level for interleukin (IL)-4, IL-10, IL-12 and interferon (IFN)-gamma were determined using semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) technique in PBMCs of these volunteers. The results clearly demonstrated a high level of IL-4 expression in nonhealing cases of CL and a low expression level of transcripts for IFN-gamma and IL-12. In contrast, a high level of IFN-gamma and IL-12 expression and a low level of IL-4 and IL-10 expression were detected in the healing cases. These findings not only support the balance of Th1/Th2 cytokines in the inducing predominant profile in healing and nonhealing cases, but it may also show the potential of rgp63 as a proper immunogen which might induce protective responses.

4106.                        Lopez-Rios F, Gonzalez-Lois C, Sotelo T. Pathologic quiz case: a patient with acquired immunodeficiency syndrome and endobronchial lesions. Arch Pathol Lab Med  2001 Nov;125(11):1511-2  No abstract.

4107.                        Mallik MK, Das DK, Haji BE. Fine needle aspiration cytology diagnosis of cutaneous leishmaniasis in a 6-month-old child: a case report. Acta Cytol  2001 Nov-Dec;45(6):1005-7

 

BACKGROUND: Skin biopsy and scrape smear examination are the two most commonly employed investigatory techniques in the diagnosis of cutaneous leishmaniasis. Although cases Leishmania lymphadenitis are reliably diagnosed with fine needle aspiration (FNA) cytology, it has not attained popularity in the diagnosis of cutaneous leishmaniasis, and only a few reports are available. CASE: A 6-month-old Kuwaiti child presented with a skin lesion on her left forearm of five months' duration. Both scrape smears and FNA were performed from the lesion. FNA cytology smears showed a rich population of inflammatory cells predominating in lymphocytes and histiocytes and epithelioid cell granulomas. The amastigote forms of Leishmania were noted on the smears. The scrape smears were nondiagnostic. CONCLUSION: FNA cytology can be reliably used in the diagnosis of cutaneous leishmaniasis, especially in dry lesions, where scrape smears are likely to be nondiagnostic.

4108.                        Ouellette M. Biochemical and molecular mechanisms of drug resistance in parasites. Trop Med Int Health  2001 Nov;6(11):874-82

 

Drug resistance is complicating the treatment of parasitic diseases. We review here the basic mechanisms of parasite resistance in malaria, sleeping sickness, leishmaniasis and common helminthiases. Parasites resort to multiple biochemical means to achieve resistance and we have begun to isolate and characterize the genes/proteins implicated in resistance. Understanding drug resistance is essential for the control of parasitic diseases.

 

4109.                        Perez-Casas C, Herranz E, Ford N. Pricing of drugs and donations: options for sustainable equity pricing. Trop Med Int Health  2001 Nov;6(11):960-4

 

Effective medicines exist to treat or alleviate many diseases which predominate in the developing world and cause high mortality and morbidity rates. Price should not be an obstacle preventing access to these medicines. Increasingly, drug donations have been established by drug companies, but these are often limited in time, place or use. Measures exist which are more sustainable and will have a greater positive impact on people's health. Principally, these are encouraging generic competition; adopting into national legislation and implementing TRIPS safeguards to gain access to cheaper sources of drugs; differential pricing; creating high volume or high demand through global and regional procurement; and supporting the production of quality generic drugs by developing countries through voluntary licenses if needed, and facilitating technology transfer.

4110.                        Salotra P, Sreenivas G, Ramesh V, Sundar S. A simple and sensitive test for field diagnosis of post kala-azar dermal leishmaniasis. Br J Dermatol  2001 Oct;145(4):630-2

BACKGROUND: Current methods for diagnosis of post kala-azar dermal leishmaniasis (PKDL) do not offer adequate sensitivity and specificity. OBJECTIVES: To develop a simple and sensitive test for field diagnosis of PKDL. METHODS: Immunochromatographic nitrocellulose strips precoated with recombinant k39 antigen were evaluated for the detection of circulating antibodies to leishmanial k39 in PKDL sera. A drop of serum applied to the strip followed by buffer led to the development of two visible bands indicating the presence of anti-k39 IgG. RESULTS: The strip test was able to detect cases of PKDL with 91% sensitivity. The specificity of the test was evaluated using controls with other skin diseases, other common infections and healthy persons from endemic and non-endemic regions. Of 125 controls examined, all were negative on the strip test, indicating 100% specificity of the test. CONCLUSIONS: The immunochromatographic nitrocellulose strips provide a non-invasive, rapid and accurate method for diagnosing PKDL.

4111.                        Wortmann G, Sweeney C, Houng HS, Aronson N, Stiteler J, Jackson J, Ockenhouse C. Rapid diagnosis of leishmaniasis by fluorogenic polymerase chain reaction. Am J Trop Med Hyg  2001 Nov;65(5):583-7

A fluorescent DNA probe (LEIS.P1) specific for a conserved region of the small-subunit ribosomal RNA gene of Leishmania and a pair of flanking primers (LEIS.U1 and LEIS.L1) were designed for use in a fluorogenic polymerase chain reaction. Optimal assay conditions with zero background were established to detect low levels of Leishmania from clinical samples. By use of this assay, we amplified DNA from 27 strains of cultured Leishmania (both Old and New World strains) and selectively amplified Leishmania DNA from 12 paraffin-embedded human biopsy samples and 3 fresh human skin biopsy specimens. For the fresh human tissue biopsies, the turnaround time from biopsy to test result was < 24 hr. No amplification was detected in negative control samples (including the kinetoplastid protozoa Trypanosoma rangelli and Crithidia fasiculata). This assay provides a specific and rapid diagnostic modality to detect infection with Leishmania.

 

July 02

4689.                        Alrajhi AA, Ibrahim EA, De Vol EB, Khairat M, Faris RM, Maguire JH.  Fluconazole for the treatment of cutaneous leishmaniasis caused by Leishmania major. N Engl J Med. 2002 Mar 21;346(12):891-5.

 

BACKGROUND: Whereas certain oral antifungal azoles are well documented to have activity against leishmania, data on the efficacy of fluconazole for leishmaniasis are limited. We conducted a controlled trial in Saudi Arabia of fluconazole for the treatment of cutaneous leishmaniasis caused by Leishmania major. METHODS: This randomized, double-blind, placebo-controlled trial assessed the efficacy of oral fluconazole, in a dose of 200 mg daily for six weeks, in the treatment of parasitologically confirmed cutaneous leishmaniasis. The primary outcome measure was the time to the complete healing of all lesions. RESULTS: A total of 106 patients were assigned to receive fluconazole, and 103 patients were assigned to receive placebo. Follow-up data were available for 80 and 65 patients, respectively. At the three-month follow-up, healing of lesions was complete for 63 of the 80 patients in the fluconazole group (79 percent) and 22 of the 65 patients in the placebo group (34 percent; relative risk of complete healing, 2.33 [95 percent confidence interval, 1.63 to 3.33]). According to an intention-to-treat analysis, the rates of healing were 59 percent and 22 percent, respectively (relative risk, 2.76 [95 percent confidence interval, 1.84 to 4.12]). Sodium stibogluconate was offered to 11 patients in the fluconazole group who returned for follow-up (14 percent) and 33 of those in the placebo group (51 percent) in whom oral treatment was judged to have failed. According to a Kaplan-Meier analysis, the time to healing was shorter for the fluconazole group (median, 8.5 weeks, as compared with 11.2 weeks in the placebo group; P<0.001 by the log-rank test). Side effects were mild and similar in both groups. CONCLUSIONS: A six-week course of oral fluconazole is a safe and useful treatment for cutaneous leishmaniasis caused by L. major.

 

4690.                        Katz KC, Walmsley SL, McLeod AG, Keystone JS, Detsky AS.  Clinical problem-solving. Where are you from? N Engl J Med. 2002 Mar 7;346(10):764-7. No abstract.

4691.                        Noyes H, Pratlong F, Chance M, Ellis J, Lanotte G, Dedet JP.  A previously unclassified trypanosomatid responsible for human cutaneous lesions in Martinique (French West Indies) is the most divergent member of the genus Leishmania ss. Parasitology. 2002 Jan;124(Pt 1):17-24.

 

Two cases of skin lesions similar to those caused by Leishmania parasites have been reported from Martinique. Parasites isolated from these lesions were unlike Leishmania reference strains by isoenzyme analysis and electron microscopy and were assumed to be monoxenous trypanosomatids which normally only infect invertebrates. Both strains have now been retyped by isoenzyme analysis and found to be identical to each other and distantly related to all other Leishmania species. The sequence of the 18S ribosomal RNA gene and partial sequences of the DNA polymerase alpha and RNA polymerase II largest subunit genes were obtained. These sequences indicated that the Martinique parasites clustered with L. enriettii and were basal to all other euleishmania. However, support for both the position basal to all euleishmania and the clustering with L. enriettii was low. The Martinique parasites may cluster with L. (Leishmania) or L. (Viannia) or form a novel clade within the euleishmania either with or without L. enriettii.

 

4692.                        Sabbatini M, Pisani A, Ragosta A, Gallo R, Borrelli F, Cianciaruso B. Visceral Leishmaniasis in renal transplant recipients: is it still a challenge to the nephrologist? Transplantation. 2002 Jan 27;73(2):299-301.

 

A case of visceral Leishmaniasis in a renal transplant recipient is reported because of its peculiar clinical presentation: the presence of most clinical signs of the disease, such as high-grade fever, marked leucopenia, and splenomegaly, but persistent negativity of serology and of bone marrow smear. Forty days after the first bone marrow biopsy, the diagnosis was made possible by a second biopsy, and the treatment was started with antimonial compounds, which led to complete remission of symptoms. A relapse was observed 1 month after discontinuation of therapy, successfully treated with a new cycle of the same drug and allopurinol. The diagnosis of Leishmaniasis must always be considered in immunosuppressed transplant recipients with fever and leucopenia of unknown origin, even when serology and bone marrow smear are negative.

 

4693.                        Sah SP, Sharma SK, Rani S.  Kala azar associated with malaria. Arch Pathol Lab Med. 2002 Mar;126(3):382-3. No abstract.

4694.                        Sousa-Atta ML, Salame GS, D'Oliveira A Jr, Almeida RP, Atta AM, Carvalho EM. Immunoglobulin E antileishmanial antibody response in cutaneous leishmaniasis. Clin Diagn Lab Immunol. 2002 Jan;9(1):101-4.

 

High levels of antileishmanial immunoglobulin E (IgE) antibodies are associated with disease activity in visceral leishmaniasis. Herein, we report our observations about the relationship between antileishmanial IgE antibodies and clinical aspects of cutaneous leishmaniasis. This study was carried out with 45 patients (29 male and 16 female), with ages ranging from 11 to 48 years. All subjects were from an area to which leishmaniasis is endemic, Corte de Pedra (Bahia, Brazil), and the duration of the illness was </=30 days. The patients were classified as positive or negative for IgE serology in enzyme-linked immunosorbent assay with leishmanial antigens. IgE antibodies were detected in 18 patients (optical density, 0.421 +/- 0.30; 95% confidence interval, 0.27 to 0.57), and only 3 (17%) had more than one ulcer. In this group the diameter of Montenegro's reaction was 18 +/- 12.2 mm. In the group with negative IgE serology, 11 of 27 patients (48%) presented two or more cutaneous ulcers, and the mean of the skin test result was 9 +/- 6.9 mm. There was a positive correlation between IgE antibody levels and Montenegro's reaction size and an inverse correlation between IgE antileishmanial antibodies and the number of skin ulcers. The presence of antileishmanial IgE antibodies in cutaneous leishmaniasis may be a result of immunoregulatory events with clinical implications.

 

4695.                        Verthelyi D, Kenney RT, Seder RA, Gam AA, Friedag B, Klinman DM. CpG oligodeoxynucleotides as vaccine adjuvants in primates. J Immunol. 2002 Feb 15;168(4):1659-63.

 

Synthetic oligodeoxynucleotides (ODN) containing unmethylated CpG motifs act as immune adjuvants in mice, boosting the humoral and cellular response to coadministered Ags. CpG ODN that stimulate human PBMC are only weakly active in mice. Thus, alternative animal models are needed to monitor the activity and safety of "human" CpG ODN in vivo. This work demonstrates that rhesus macaques recognize and respond to the same CpG motifs that trigger human immune cells. Coadministering CpG ODN with heat-killed Leishmania vaccine provided significantly increased protection of macaques against cutaneous Leishmania infection. These findings indicate that rhesus macaques provide a useful model for studying the in vivo activity of human CpG motifs, and that ODN expressing these motifs act as strong immune adjuvants.

 

Oct 2002

5437.                        Anuja K. Recombinant fusion of functional regions of gp63 of leishmania with LTB of E. coli: expression, immunogenecity and efficacy to block steps important for leishmaniasis. Department of Chemistry, Gauhati University, Guwahati. 2001. No abstract.

5438.                        Bourreau E, Prevot G, Gardon J, Pradinaud R, Hasagewa H, Milon G, Launois P. LACK-specific CD4(+) T cells that induce gamma interferon production in patients with localized cutaneous leishmaniasis during an early stage of infection. Infect Immun. 2002 Jun;70(6):3122-9.

 

The profile of cytokines induced by soluble leishmania antigen (SLA) and the Leishmania homologue of the mammalian receptor for activated C kinase (LACK), a candidate vaccine against leishmaniasis, and the cellular source of the cytokines produced in response to these antigens were analyzed in patients infected with Leishmania guyanensis. Gamma interferon (IFN-gamma) and interleukin-10 (IL-10) were produced in response to LACK. Although LACK-specific CD4(+) cells producing IFN-gamma were isolated only during the early phase of infection (less than 30 days following the onset of infection), cells producing IL-10 in response to LACK were detected in all patients. CD4(+) T cells producing IFN-gamma and IL-13 were produced in response to SLA in all patients. SLA- and LACK-specific T cells are effector memory cells, as they are CD45RA(-) CCR7(-) CD4(+) T cells. CD4(+) T cells producing IFN-gamma are CD62L(-), and CD4(+) T cells producing IL-10 are CD62L(+), indicating that these cells have different tissue-homing capacities. These findings show that SLA and LACK induce both type 1 (IFN-gamma) and type 2 (IL-10 or IL-13) cell responses.

5439.                        Follador I, Araujo C, Bacellar O, Araujo CB, Carvalho LP, Almeida RP, Carvalho EM. Epidemiologic and immunologic findings for the subclinical form of Leishmania braziliensis infection. Clin Infect Dis  2002 Jun 1;34(11):E54-8

 

The epidemiologic and immunologic findings for 104 subjects with subclinical Leishmania braziliensis infection were compared with those for 29 patients with cutaneous leishmaniasis (CL) from the same area of endemicity. Subjects had a positive leishmania skin test result and remained asymptomatic during the next 4 years of follow-up were considered to have subclinical infection. Patients with CL were younger, had larger-diameter indurations after skin testing, and were more likely to have positive serologic markers than were those with subclinical infection (P<.05). In subjects with subclinical infection, levels of interferon-gamma and tumor necrosis factor-alpha in lymphocyte supernatants were lower than they were in patients with CL (P<.05); however, mean interleukin-5 levels were slightly higher in patients with subclinical infection than in patients with CL. These data indicate that, unlike patients with CL, individuals who do not develop disease when infected with L. braziliensis may have the ability to modulate their immune response.

 

5440.                        Hailu A. The use of direct agglutination test (DAT) in serological diagnosis of Ethiopian cutaneous leishmaniasis. Diagn Microbiol Infect Dis  2002 Apr;42(4):251-6

 

Leishmania aethiopica (L.a.) is the main species of Leishmania that causes Ethiopian cutaneous leishmaniasis (ECL). The routine diagnosis of ECL depends on parasitological examination of smear, culture or biopsy. In this study, DAT was set-up and evaluated for its diagnostic performance using defined sera of 45 ECL patients, 18 visceral leishmaniasis (VL) patients, 12 patients with other diseases, and 37 normal controls. The test was also evaluated in 64 patients clinically diagnosed as ECL, leprosy, or other skin diseases. Using L.a. derived antigen, the sensitivity and specificity of the test was determined to be 90.5% and 91.8% respectively. However, using antigen derived from a non-homologous strain, only 4 sera of 21 active ECL patients were positive. Eighteen sera of VL patients were positive irrespective of the different antigen sources. The data show that DAT can be a useful addition to the diagnosis of ECL.

5441.                        Kafetzis DA, Maltezou HC. Visceral leishmaniasis in paediatrics. Curr Opin Infect Dis. 2002 Jun;15(3):289-94. Review.

 

Visceral leishmaniasis is a vector-borne systemic infection, which affects half a million people each year in many areas of the world. Typical disease manifests with fever, hepatosplenomegaly, pancytopenia, and progressive deterioration of the host. Although molecular methods appear promising as a non-invasive diagnostic tool, definite diagnosis still relies on the demonstration of the parasite in tissue. Pentavalent antimonial compounds remain the mainstay of treatment worldwide, except in India. During the past decade, short courses of lipid formulations of amphotericin B were assessed and proved effective; however, their cost precludes their wide use in developing countries. Miltefosine, an oral active agent, was recently identified, and might fulfil our expectations for an effective, safe, easily administered and affordable antileishmanial treatment.

5442.                        Machado P, Araujo C, Da Silva AT, Almeida RP, D'Oliveira Jr A, Bittencourt A, Carvalho EM. Failure of early treatment of cutaneous leishmaniasis in preventing the development of an ulcer. Clin Infect Dis. 2002 Jun 15;34(12):E69-73.

 

The clinical characteristics and treatment outcome were determined for 26 patients who presented with early-stage cutaneous leishmaniasis. Illness duration ranged from 8 to 20 days, and the commonest clinical presentation was the presence of a papule with small central crust on a lower extremity. Prominent regional adenopathy was found in 22 (85%) of 26 patients. The results of an intradermal skin test for Leishmania were positive for 96% of those patients, and results of serologic testing were positive for 61% of patients tested. Ten (46%) of 22 patients for whom follow-up data were available developed enlargement and ulceration of the lesion despite early antimony therapy and required additional courses of treatment. Histopathological studies of samples from the lesions of 3 patients showed vasculitis. These data show that early therapy for cutaneous leishmaniasis does not prevent the development of an ulcer in one-half of patients. This unfavorable outcome underlines the relevance of local exacerbated inflammatory and immune response in the pathogenesis of the disease.

5443.                        Morales MA, Cruz I, Rubio JM, Chicharro C, Canavate C, Laguna F, Alvar J. Relapses versus reinfections in patients coinfected with Leishmania infantum and human immunodeficiency virus type 1. J Infect Dis. 2002 May 15;185(10):1533-7.

 

In the Mediterranean basin, Leishmania infantum is a major opportunistic parasite in people with acquired immunodeficiency syndrome (AIDS), and up to 9% of the patients with AIDS suffer from newly acquired or reactivated visceral leishmaniasis. Distinguishing between reinfections and relapses in these patients is important because some apparent treatment failures occur in patients with new rather than reactivated infections. Isoenzyme characterization is limited for use in determining relapsed versus newly acquired leishmaniasis in human immunodeficiency virus (HIV)-infected patients because of the variability of L. infantum and the predominance of the MON-1 zymodeme in people coinfected with HIV. A seminested polymerase chain reaction (PCR) was used to amplify L. infantum minicircle kinetoplast DNA, and, after digestion, the restriction fragment-length polymorphism (RFLP) profiles showed that 3 (7.5%) of 40 patients coinfected with L. infantum and HIV had a new infection, whereas isoenzyme characterization indicated that all 40 patients had infection relapses. These results suggest the utility of this PCR-RFLP analysis in detecting leishmaniasis reinfection in HIV-positive patients.

 

5444.                        Royer MA, Crowe CO. American cutaneous leishmaniasis. Arch Pathol Lab Med. 2002 Apr;126(4):471-3.

 

We present 3 cases of American cutaneous leishmaniasis occurring in soldiers of a unit of US Army Rangers who parachuted into the jungles of Panama. Shortly after returning to the United States, these 3 soldiers each developed a crusted, indurated papule, which slowly enlarged during the following 6 weeks. Routine microscopy of skin biopsies revealed a dermal granulomatous inflammation and a predominantly lymphoid infiltrate. Numerous histiocytes contained small oval organisms with bar-shaped paranuclear kinetoplasts, morphologically consistent with leishmanial parasites. Cultures grew Leishmaniasis brasiliensis, subspecies panamensis. The soldiers were treated with intravenous pentavalent antimonial therapy daily for 20 days with good clinical improvement. Epidemics of leishmaniasis occur periodically in tropical regions of the world, and leishmaniasis has emerged in new settings, for example, as an acquired immunodeficiency syndrome-associated opportunistic infection. With an increasingly mobile society, it is important to be familiar with the clinical and histopathologic appearance of conditions such as leishmaniasis, which are common in tropical and subtropical regions and are increasingly significant in other regions of the world.

 

5445.                        Sahoo B, Kaur I, Radotra BD, Kumar B. Cutaneous leishmaniasis in hilly areas of Himachal Pradesh. J Dermatol. 2002 Apr;29(4):248-9.  No abstract.

Pathogenesis:

5446.                        Cunningham AC. Parasitic adaptive mechanisms in infection by eishmania. Exp Mol Pathol. 2002 Apr;72(2):132-41. Review.

 

Leishmania are a resilient group of intracellular parasites that infect macrophages. The resultant complex of diseases, or leishmaniases, caused by the parasites affect over twelve million people worldwide. Leishmania have developed unique adaptive mechanisms to ensure their survival in the harsh environments faced throughout their life cycle. These parasites must not only contend with the hostile digestive conditions found within the sand fly vector, but they must also avoid destruction by the host immune system while in the bloodstream, before entering the macrophage. To do so, Leishmania express unique lipophosphoglycan (LPG) molecules and the metalloprotease gp63, among other proteins, on their cell surface. To enter the macrophage, Leishmania utilizes a variety of cellular receptors to mediate endocytosis. Once inside the macrophage, Leishmania is protected from phagolysosome degradation by a variety of adaptations to inhibit cellular defense mechanisms. These include the inhibition of phagosome-endosome fusion, hydrolytic enzymes, cell signaling pathways, nitric oxide production, and cytokine production. While other parasites can also infect macrophages, Leishmania is distinctive in that it not only relies on its own defenses to survive and reproduce within the macrophage phagolysosome, but Leishmania also manipulates the host immune response in order to protect itself and to gain entry into the cell. These unique adaptive mechanisms help promote Leishmania survival. Copyright 2002 Elsevier Science (USA).

 

Vaccines:

5447.                        Campos-Neto A, Webb JR, Greeson K, Coler RN, Skeiky YA, Reed SG. Vaccination with plasmid DNA encoding TSA/LmSTI1 leishmanial fusion proteins confers protection against Leishmania major infection in susceptible BALB/c mice. Infect Immun. 2002 Jun;70(6):2828-36.

 

We have recently shown that a cocktail containing two leishmanial recombinant antigens (LmSTI1 and TSA) and interleukin-12 (IL-12) as an adjuvant induces solid protection in both a murine and a nonhuman primate model of cutaneous leishmaniasis. However, because IL-12 is difficult to prepare, is expensive, and does not have the stability required for a vaccine product, we have investigated the possibility of using DNA as an alternative means of inducing protective immunity. Here, we present evidence that the antigens TSA and LmSTI1 delivered in a plasmid DNA format either as single genes or in a tandem digene construct induce equally solid protection against Leishmania major infection in susceptible BALB/c mice. Immunization of mice with either TSA DNA or LmSTI1 DNA induced specific CD4(+)-T-cell responses of the Th1 phenotype without a requirement for specific adjuvant. CD8 responses, as measured by cytotoxic-T-lymphocyte activity, were generated after immunization with TSA DNA but not LmSTI1 DNA. Interestingly, vaccination of mice with TSA DNA consistently induced protection to a much greater extent than LmSTI1 DNA, thus supporting the notion that CD8 responses might be an important accessory arm of the immune response for acquired resistance against leishmaniasis. Moreover, the protection induced by DNA immunization was specific for infection with Leishmania, i.e., the immunization had no effect on the course of infection of the mice challenged with an unrelated intracellular pathogen such as Mycobacterium tuberculosis. Conversely, immunization of BALB/c mice with a plasmid DNA that is protective against challenge with M. tuberculosis had no effect on the course of infection of these mice with L. major. Together, these results indicate that the protection observed with the leishmanial DNA is mediated by acquired specific immune response rather than by the activation of nonspecific innate immune mechanisms. In addition, a plasmid DNA containing a fusion construct of the two genes was also tested. Similarly to the plasmids encoding individual proteins, the fusion construct induced both specific immune responses to the individual antigens and protection against challenge with L. major. These results confirm previous observations about the possibility of DNA immunization against leishmaniasis and lend support to the idea of using a single polygenic plasmid DNA construct to achieve polyspecific immune responses to several distinct parasite antigens.

 

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