A battery of 12 microsatellite markers for genetic analysis of the Leishmania (Viannia) guyanensis complex.

We used 12 microsatellite markers developed for Leishmania braziliensis to genotype 28 strains of the main species of the Leishmania guyanensis complex (i.e. L. guyanensis and L. panamensis) collected in Ecuador and Peru. The important heterozygote deficits observed in these populations are similar with the previous data obtained in L. braziliensis and raise again the debate on the reproductive mode of these protozoan parasites. The data showed genetic polymorphism and geographical differentiation giving information on population structure of the L. guyanensis complex. Regarding the two species, this study enhances again the debate on the taxonomic status of the different isolates belonging to L. guyanensis s.l. since the results showed substantial heterogeneity within this species complex. In conclusion, this study increases the number of available microsatellite loci for L. guyanensis species complex and raises fundamental biological questions. It confirms that microsatellite markers constitute good tools for population genetic studies on parasites of this complex.

Localized Cutaneous Leishmaniasis due to Leishmania infantum in a Patient Treated with Infliximab.

We report the first case of cutaneous leishmaniasis in a patient treated with infliximab. The species was Leishmania infantum, agent of both cutaneous leishmaniasis and visceral leishmaniasis. Cutaneous leishmaniasis occurred after the 9th infusion of infliximab in a patient who was suffering from ankylosing spondylitis.

Visceral leishmaniasis infection in a rheumatoid arthritis patient treated with infliximab.

Anti-TNFalpha strategies can result in significant clinical benefits in rheumatoid arthritis (RA), but with an increased rate of opportunistic infections. Visceral leishmaniasis (VL) is a severe disease that can develop in immunocompromised hosts, principally in HIV patients. VL in RA patients treated with TNFalpha antagonists is an extremely rare event, and only one case has been described. Here we report a case of VL, occurring after 9 infusions of infliximab in association with azathioprine, in a patient who developed blood cytopenia, fluctuant fever, and splenomegaly.

Mucosal relapse of visceral leishmaniasis in a child treated with anti-TNFα.

Visceral leishmaniasis is an enzootic parasitosis present across the Mediterranean Basin. Some consider it an opportunistic parasite. We report the case of a girl treated with anti-tumour necrosis factor alpha (anti-TNFα) for juvenile idiopathic arthritis who had previously presented with visceral leishmaniasis. Two and a half years later, she presented a tumour-like mass in the nasal mucous membrane caused by Leishmania parasites. Leishmania infantum is classically responsible for visceral leishmaniasis, but pure mucocutaneous leishmaniasis has also been described. To our knowledge, this is the first observation of a recurrence of visceral leishmaniasis in the mucocutaneous form. The occurrence of atypical forms and presentations in those on anti-TNF therapy should be considered.

Visceral leishmaniasis and HIV-1 co-infection in southern France.

Between 1986 and 1993 visceral leishmaniasis (VL) was diagnosed in 50 adult patients with human immunodeficiency virus type 1 (HIV-1) infection (8 females, 42 males: 31 intravenous drug users, 11 homosexual or bisexual men, 6 heterosexual individuals, 2 blood recipients) from 5 hospital centres in southern France. Diagnosis of VL was by demonstration of Leishmania and isolation of promastigotes by culture in Novy-McNeal-Nicolle medium. Leishmania isolates were identified by their isoenzyme profile in 28 patients. All the patients were immunocompromised when VL was diagnosed. Their median CD4 cell count was 25 x 10(6) (0-200). However, only 21 patients (42%) fulfilled the 1987 CDC criteria for the acquired immune deficiency syndrome before VL developed. Fever (84%), splenomegaly (56%), hepatomegaly (34%), and pancytopenia (62%) were the most common presenting features. Clinical signs were lacking in 10% of patients. Anti-leishmanial antibodies were detected by indirect immunofluorescence or enzyme-linked immunosorbent assay in 26/47 cases (55%). Combining these techniques with Western blotting (WB) gave a positivity rate of 95%. Amastigotes were demonstrated in bone marrow aspirates in 47 cases (94%). Unusual sites for parasites were found in 17 patients (34%), mainly in the digestive tract but also skin and lung. Viscerotropic L. infantum zymodeme MON-1 was characterized in 86% of cases. Dermotropic zymodemes MON-24, MON-29, MON-33, and a previously undescribed zymodeme MON-183, were isolated from 4 patients. The response rate to pentavalent antimony was 50% and to amphotericin B 100%, but clinical relapses were noted in both groups. In endemic areas, VL should be considered as a possible opportunistic infection in HIV-infected patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Leishmania infantum and L. major in Algeria.

Since 1980, the development of leishmaniasis in Algeria has been marked by a considerable increase in the number of cases of both visceral leishmaniasis (1121 cases recorded) and cutaneous leishmaniasis (more than 2000 cases per year). New Leishmania infantum and L. major foci have appeared in the north and south of the country. During this period, 100 strains of Leishmania isolated from humans, other mammals and sandflies have been identified. The presence of L. major MON-25 in Psammomys obesus and Phlebotomus papatasi had identified these species as the main reservoir and vector, respectively, of zoonotic cutaneous leishmaniasis. Similarly, the presence of L. infantum MON-1 in Ph. perniciosus and dogs has implicated them as the vector and reservoir of visceral leishmaniasis. The isolation of the dermotropic zymodeme MON-24 of L. infantum from Ph. perfiliewi suggested that it was one of the main vectors of cutaneous leishmaniasis in the north of the country; the reservoir has not been identified. In addition, other zymodemes of Leishmania have been identified in visceral leishmaniasis patients, frequently associated with human immunodeficiency virus (MON-24, MON-33, MON-34 and MON-78), in patients with cutaneous leishmaniasis (MON-80), and in dogs with leishmaniasis (MON-34 and MON-77).

Visceral leishmaniasis. Persistence of parasites in lymph nodes after clinical cure.

Visceral leishmaniasis (VL) is generally associated with severe immunodeficiency (AIDS; renal, liver, and heart transplantations; haemopoietic malignancies). More rarely it can be related to an immunotolerence status such as pregnancy. Various observations report the development of leishmaniasis several months or even years after exposure to the parasite. Relapses occur rarely in patients not known to be immunocompromised, but are common after incomplete treatment. They are frequent in patients with Leishmania/HIV co-infection. Asymptomatic phases and relapses suggest that parasite can exist in the tissues for a long time before and/or after clinical onset of the disease. The mechanisms of onset of clinical leishmaniasis following exposure and infestation are highly relevant to understanding the pathology of the disease. The survival of Leishmania parasite between infection and disease or after cure is a very important issue for clinicians and epidemiologists. We describe two cases of VL occurring in a patient with lymphoma and in a pregnant woman. In both cases, parasites remained present in the lymph nodes after clinical cure.

[Human cutaneous leishmaniasis caused by Leishmania Major MON-26 in the region of Damascus (Syria)]. / La leishmaniose cutanée humaine à Leishmania major MON-26 aux environs de Damas (Syrie).

In response to an epidemic of oriental sore around Damascus, an ecological and epidemiological survey was carried out in the village of Dmeir, 40 km NE of Damascus. Parasites isolated from six cases from Dmeir, and two other cases from Syria were identified as Leishmania major, zymodeme MON-26. This zymodeme is known as the agent of zoonotic cutaneous leishmaniasis from the Sub-Saharian Sahel to the Near and Middle East. This is the first report of L. major in Syria. In a group of 234 school children aged 5-11 years, the leishmanin skin test was positive in 37%, indicating a high transmission rate. The epidemic seems to be the result of agricultural and industrial development projects in the area: numbers of both the gerbil reservoir host and sandfly vector appear to be increased by the land improvement.

[Visceral leishmaniasis in Cameroon. Seroepidemiologic survey in the Kousseri region, north Cameroon]. / Leishmaniose viscérale au Cameroun. Enquête séro-épidémiologique dans la région de Kousseri, Nord-Cameroun.

A sero-epidemiological survey of school children was carried out in Kousseri, a focus for visceral leishmaniasis. Sero-immunological assays for the detection of anti-Leishmania antibodies were based on the indirect immunofluorescence assay test and counter-immunoelectrophoresis. 9 out of 223 school children tested positive for visceral leishmaniasis (seroprevalence rate of 4%). These 9 cases had no history of the disease. The data obtained confirm the endemicity of visceral leishmaniasis in this focus and call for extensive studies in order to determine the prevalence of the disease in the entire population as well as the main components of the transmission cycle.

[Canine leishmaniasis from Leishmania infantum: value and production of the latex test. Ecoepidemiologic applications]. / Leishmaniose canine à Leishmania infantum: intérêt et réalisation du test au latex. Applications en éco-épidémiologie.

The authors relate the realization, evaluation and eco-epidemiological applications of a "field-test": the agglutination of latex particles coated with a soluble antigen of Leishmania infantum in the presence of homologous antibodies. Evaluated on 1,035 canine sera, the sensitivity of the latex agglutination test (LAT) was 93.4% compared to the indirect fluorescent antibody test (IFAT). 90 node cultures were carried out on dogs with positive or negative LAT and/or positive or negative IFAT. The frequency of positive node cultures (70%) as versus positive LAT came between the results obtained for an IFAT > 1/40 (64%) and IFAT > 1/80 (73%). 32/33 (97%) dogs had positive node culture, LAT and IFIAT(> 1/80). 6 dogs had negative LAT but positive node culture: 5 of these had also an IFAT < 1/160. This test was used in the field on several eco-epidemiological surveys in leishmanian enzootic areas. Node cultures were made on the dogs with positive TL. 39 strains were isolated: 18 in Algeria, 15 in Morocco, 2 in Syria and 4 in Yemen. 13/39 strains were obtained from dogs with IFI < 1/160: 2 at 1/20, 8 at 1/40 and 3 at 1/80. In Algeria this test was also used for the diagnosis of human visceral leishmaniasis in a child. This quick, simple, sensitive and specific test could be usefully carried out on "field" surveys for the diagnosis of visceral-leishmaniasis in animals and human beings.

Frequency of drug resistance gene amplification in clinical leishmania strains.

Experimental studies about Leishmania resistance to metal and antifolates have pointed out that gene amplification is one of the main mechanisms of drug detoxification. Amplified genes code for adenosine triphosphate-dependent transporters (multidrug resistance and P-glycoproteins P), enzymes involved in trypanothione pathway, particularly gamma glutamyl cysteine synthase, and others involved in folates metabolism, such as dihydrofolate reductase and pterine reductase. The aim of this study was to detect and quantify the amplification of these genes in clinical strains of visceral leishmaniasis agents: Leishmania infantum, L. donovani, and L. archibaldi. Relative quantification experiments by means of real-time polymerase chain reaction showed that multidrug resistance gene amplification is the more frequent event. For P-glycoproteins P and dihydrofolate reductase genes, level of amplification was comparable to the level observed after in vitro selection of resistant clones. Gene amplification is therefore a common phenomenon in wild strains concurring to Leishmania genomic plasticity. This finding, which corroborates results of experimental studies, supports a better understanding of metal resistance selection and spreading in endemic areas.

Canine visceral leishmaniasis caused by Leishmania infantum in Senegal: risk of emergence in humans?

In the context of global warming and the risk of spreading arthropod-borne diseases, the emergence and reemergence of leishmaniasis should not be neglected. In Senegal, over the past few years, cases of canine leishmaniasis have been observed. We aim to improve the understanding of the transmission cycle of this zoonosis, to determine the responsible species and to evaluate the risk for human health. An epidemiological and serological study on canine and human populations in the community of Mont Rolland (Thiès area) was conducted. The data showed a high seroprevalence of canine leishmaniasis (>40%) and more than 30% seropositive people. The dogs' seroprevalence was confirmed by PCR data (concordance > 0.85, Kappa > 0.7). The statistical analysis showed strong statistical associations between the health status of dogs and seropositivity, the number of positive PCRs, clinical signs and the number of Leishmania isolates. For the first time, the discriminative PCRs performed on canine Leishmania strains clearly evidenced that the pathogenic agent is Leishmania infantum. The results obtained show that transmission of this species is well established in this area. That the high incidence of seropositivity in humans may be a consequence of infection with this species is discussed.