Tegumentary leishmaniasis by Leishmania braziliensis complex in Cochabamba, Bolivia including the presence of L. braziliensis outlier: Tegumentary leishmaniasis in Cochabamba, Bolivia: Tegumentary leishmaniasis in Cochabamba, Bolivia.

Leishmaniasis is caused by protozoans of the Leishmania genus, which includes more than 20 species capable of infecting humans worldwide. In the Americas, the most widespread specie is L. braziliensis, present in 18 countries including Bolivia. The taxonomic position of the L. braziliensis complex has been a subject of controversy, complicated further by the recent identification of a particular subpopulation named L. braziliensis atypical or outlier. The aim of this study was to carry out a systematic analysis of the L. braziliensis complex in Bolivia and to describe the associated clinical characteristics. Forty-one strains were analyzed by sequencing an amplified 1245 bp fragment of the hsp70 gene, which allowed its identification as: 24 (59%) L. braziliensis, 16 (39%) L. braziliensis outlier, and one (2%) L. peruviana. In a dendrogram constructed, L. braziliensis and L. peruviana are grouped in the same cluster, whilst L. braziliensis outlier appears in a separate branch. Sequence alignment allowed the identification of five non-polymorphic nucleotide positions (288, 297, 642, 993, and 1213) that discriminate L. braziliensis and L. peruviana from L. braziliensis outlier. Moreover, nucleotide positions 51 and 561 enable L. peruviana to be discriminated from the other two taxa. A greater diversity was observed in L. braziliensis outlier than in L. braziliensis-L. peruviana. The 41 strains came from 32 patients with tegumentary leishmaniasis, among which 22 patients (69%) presented cutaneous lesions (11 caused by L. braziliensis and 11 by L. braziliensis outlier) and 10 patients (31%) mucocutaneous lesions (eight caused by L. braziliensis, one by L. braziliensis outlier, and one by L. peruviana). Nine patients (28%) simultaneously provided two isolates, each from a separate lesion, and in each case the same genotype was identified in both. Treatment failure was observed in six patients infected with L. braziliensis and one patient with L. peruviana.

Phenotypical and genotypical differences among Leishmania (Leishmania) amazonensis isolates that caused different clinical frames in humans and dogs: A systematic review.

Leishmania (Leishmania) amazonensis is an important etiological agent of American cutaneous leishmaniasis (ACL) in Brazil. The species causes a large spectrum of clinical manifestations in humans and dogs, ranging from cutaneous, cutaneous diffuse, mucocutaneous, and visceral involvement, however, the factors that drive the development of different disease forms by the same species are not yet fully known. In the present work, it was systematically reviewed the studies addressing phenotypic and genotypic characteristics of Leishmania (L.) amazonensis isolates causing cutaneous and visceral clinical frames in humans and dogs, comparing the results observed. For this, four research databases were searched for the following keywords: (Leishmania amazonensis AND visceral leishmaniasis) AND (tropism OR virulence OR visceralization OR adaptations OR mutation OR clinical presentation OR resistance OR survival OR wide spectrum). The results revealed that the complexity disease seems to involve the combination of genetic factors of the parasite (as modifications in molecules related to the virulence and metabolism) and also of the host's immune background and status. Nonetheless, the exact mechanism that leads to different clinical manifestations between strains of the same species is still uncertain and future studies must be developed to better elucidate this phenomenon.

Molecular Evidence of Leishmania infantum and Leishmania guyanensis in Red Howler Monkey (Alouatta seniculus) from French Guiana.

Presence of Leishmania spp. was evaluated in the blood of nine red howler monkeys (Alouatta seniculus) from a specific area of French Guiana, located in the northeast of the Amazon. The molecular detection was performed based on PCR targeting the markers 18S rRNA, kDNA and ITS2 genes, as well as rapid immunomigration tests. Two monkeys were positive for Leishmania infantum and one for Leishmania guyanensis. While L. guyanensis cutaneous leishmaniasis is common, visceral leishmaniasis (human and canine) caused by L. infantum has never been described in this area. The howler monkey proved to be a sentinel and a potential reservoir of a serious zoonosis. These results must be carefully considered by public health officials and veterinarians in the future.

MyD88 and TLR9 dependent immune responses mediate resistance to Leishmania guyanensis infections, irrespective of Leishmania RNA virus burden.

Infections with Leishmania parasites of the Leishmania Viannia subgenus give rise to both localized cutaneous (CL), and metastatic leishmaniasis. Metastasizing disease forms including disseminated (DCL) and mutocutaneous (MCL) leishmaniasis result from parasitic dissemination and lesion formation at sites distal to infection and have increased inflammatory responses. The presence of Leishmania RNA virus (LRV) in L. guyanensis parasites contributes to the exacerbation of disease and impacts inflammatory responses via activation of TLR3 by the viral dsRNA. In this study we investigated other innate immune response adaptor protein modulators and demonstrated that both MyD88 and TLR9 played a crucial role in the development of Th1-dependent healing responses against L. guyanensis parasites regardless of their LRV status. The absence of MyD88- or TLR9-dependent signaling pathways resulted in increased Th2 associated cytokines (IL-4 and IL-13), which was correlated with low transcript levels of IL-12p40. The reliance of IL-12 was further confirmed in IL12AB-/- mice, which were completely susceptible to infection. Protection to L. guyanensis infection driven by MyD88- and TLR9-dependent immune responses arises independently to those induced due to high LRV burden within the parasites.

Is Leishmania (Viannia) braziliensis preferentially restricted to the cutaneous lesions of naturally infected dogs?

Nineteen dogs naturally infected with Leishmania (Viannia) braziliensis were studied in order to determine the presence of the parasite outside cutaneous lesions. Eleven (57.9%) animals showed single cutaneous or mucosal lesions and eight (42.1%) presented two or three lesions. Twenty-eight active lesions were biopsied. Isolation in culture and characterization by enzyme electrophoresis were possible in 100% of cases and amastigote forms were visualized upon histopathological examination in three samples (n=25, 12%). Isolation of the parasite in culture from peripheral blood and intact skin fragments obtained from the scapular region was negative in all animals, as was the histopathological analysis of skin from this region. Serological reactivity determined by an immunofluorescent antibody test and/or enzyme-linked immunosorbent assay was demonstrated in 15 animals. The results obtained suggest that L. braziliensis preferentially remains at the site of lesion, in contrast to the systemic distribution of parasites observed in dogs infected with L. (Leishmania) chagasi. A better understanding of this aspect may help direct diagnostic and control strategies applicable to areas characterized by the simultaneous occurrence of the cutaneous and visceral forms of leishmaniasis, as is the case for the Municipality of Rio de Janeiro, Brazil.

New World leishmaniasis from Spain.

A 69 year old man living in Spain contracted mucocutaneous leishmaniasis involving the nose. The infecting organism was Leishmania infantum, which only rarely causes the New World form of the disease. The source of infection was probably a neighbour's dog. The patient began treatment with liposomal amphotericin B but died of pneumonia two months later.

[Mucocutaneous leishmaniasis in naturally infected dogs in Salta, Argentina]. / Leishmaniosis mucocutánea en perros naturalmente infectados en Salta, Argentina.

The objective of the present study is to describe two cases of dogs with mucocutaneous lesions caused by Leishmania spp. Both dogs presented destruction of the nasal septum, hyperemia with soft palate edema and barking alteration due to laryngeal compromise. Biopsies were taken from the lesion border and Leishmania spp. amastigotes were seen in the imprints. The dogs presented positive serology when complex soluble antigen from Leishmania mexicana was used. One of the dogs was also suspected to be infected by Trypanosoma cruzi as suggested by its positive reaction with a purified specific antigen, Ag163B6-cruzipain. Most of the studies concerning leishmaniosis in dogs have described the cutaneous form of this disease in close association with human cases of Leishmania infection instead of the mucocutaneous form described herein. The presence of dogs with mucocutaneous leishmaniosis alerts on an increase of the prevalence of this form in humans, which can cause deforming lesions, alterations of the speech and even an inadequate nutrition due to difficulties in deglutition.

Leishmaniosis mucocutánea en perros naturalmente infectados en Salta, Argentina / Mucocutaneous leishmaniasis in naturally infected dogs in Salta, Argentina

The objective of the present study is to describe two cases of dogs with mucocutaneous lesions caused by Leishmania spp. Both dogs presented destruction of the nasal septum, hyperemia with soft palate edema and barking alteration due to laryngeal compromise. Biopsies were taken from the lesion border and Leishmania spp. amastigotes were seen in the imprints. The dogs presented positive serology when complex soluble antigen from Leishmania mexicana was used. One of the dogs was also suspected to be infected by Trypanosoma cruzi as suggested by its positive reaction with a purified specific antigen, Ag163B6-cruzipain. Most of the studies concerning leishmaniosis in dogs have described the cutaneous form of this disease in close association with human cases of Leishmania infection instead of the mucocutaneous form described herein. The presence of dogs with mucocutaneous leishmaniosis alerts on an increase of the prevalence of this form in humans, which can cause deforming lesions, alterations of the speech and even an inadequate nutrition due to difficulties in deglutition.

Leishmaniosis mucocutánea en perros naturalmente infectados en Salta, Argentina / Mucocutaneous leishmaniasis in naturally infected dogs in Salta, Argentina

The objective of the present study is to describe two cases of dogs with mucocutaneous lesions caused by Leishmania spp. Both dogs presented destruction of the nasal septum, hyperemia with soft palate edema and barking alteration due to laryngeal compromise. Biopsies were taken from the lesion border and Leishmania spp. amastigotes were seen in the imprints. The dogs presented positive serology when complex soluble antigen from Leishmania mexicana was used. One of the dogs was also suspected to be infected by Trypanosoma cruzi as suggested by its positive reaction with a purified specific antigen, Ag163B6-cruzipain. Most of the studies concerning leishmaniosis in dogs have described the cutaneous form of this disease in close association with human cases of Leishmania infection instead of the mucocutaneous form described herein. The presence of dogs with mucocutaneous leishmaniosis alerts on an increase of the prevalence of this form in humans, which can cause deforming lesions, alterations of the speech and even an inadequate nutrition due to difficulties in deglutition.(AU)

Canine mucosal leishmaniasis.

Four dogs infected with Leishmania had proliferative lesions on the mucosae of the penis, tongue, oral cavity, prepuce, or nose. These mucosal, nodular lesions produced by parasites of the genus Leishmania have not been described previously in the dog. Leishmaniasis should be considered in the differential diagnosis of tumor-like lesions of mucous membranes.

Distribution and etiology of leishmaniasis in Colombia.

A total of 340 Leishmania strains, isolated from humans, animals, and sand flies from various regions of Colombia, were examined by isozyme electrophoresis. Seven different Leishmania species were identified. Leishmania panamensis and L. braziliensis were the most common, representing 53.8% and 30.3% of the total, respectively. Isolation rates of the other species were as follows: L. chagasi, 9.4%; L. guyanensis, 2.6%; L. amazonensis, 1.8%; L. mexicana, 0.8%; and a new species requiring additional study, 1.2%. Statistical analyses of representative L. panamensis and L. braziliensis isolates indicated that the populations of these 2 species are genetically very similar. L. panamensis may have a continuous distribution in Colombia west of the eastern Andes Mountains and L. braziliensis may have a continuous distribution east of the western Andes Mountains. Information is given on disease manifestations of the parasites in human hosts and on isolation records from sand flies and animals.

Canine American cutaneous leishmaniasis: a clinical and immunological study in dogs naturally infected with Leishmania braziliensis braziliensis in an endemic area of Rio de Janeiro, Brazil.

Clinical and immunological findings from 35 dogs infected with Leishmania braziliensis braziliensis are described. The majority of the dogs had ulcerated single lesions on the ears. Sera from all infected dogs showed detectable Leishmania-induced antibodies using an indirect fluorescent antibody test. Antimonial therapy resulted in prompt healing of the lesions in 80.9% of the animals followed by a significant reduction in the anti-Leishmania antibody titers. However, treatment follow-up showed recurrences at the site of the primary lesion in 42.8% of the cases. These data were correlated with a persistence of the parasite in clinically healed lesions as well as with a negative intradermal test (leishmanin-delayed type hypersensitivity) observed in all animals but one.

[Natural infection of Equus asinus by Leishmania braziliensis braziliensis-Bahia, Brazil]. / Infecção natural de Equus asinus por Leishmania braziliensis braziliensis-Bahia, Brasil.

In Corte de Pedra, Valença, state of Bahia, a donkey, Equus asinus, was found naturally infected with Leishmania braziliensis braziliensis. The parasite was isolated from a lesion located on a castration scar, and identified by means of monoclonal antibodies.

A focus of mucocutaneous leishmaniasis in Três Braços, Bahia, Brazil: characterization and identification of Leishmania stocks isolated from man and dogs.

The characterization and identification to species and subspecies of 20 stocks of Leishmania isolated from the region of Três Braços, Bahia, Brazil, are described: 17 stocks were from patients and three from dogs. The following techniques were used (i) biological (growth in culture, hamster tissues and phlebotomine gut), (ii) biochemical (isoenzyme and kinetoplast DNA analysis) and (iii) immunological (using monoclonal antibodies). All except two stocks belong to the L. braziliensis complex. One of these two corresponded to L. mexicana amazonensis but the other, while clearly in the mexicana complex, showed slight differences from the L. mexicana amazonensis reference strain on isoenzyme analysis. Two stocks from different lesions in the same patient and with different growth characteristics in hamster tissues were both identified as L. braziliensis braziliensis. All the fully characterized stocks of the L. braziliensis complex were identified as L. braziliensis braziliensis. L. braziliensis guyanensis was not identified. Dog and human stocks of L. braziliensis braziliensis were indistinguishable. From these findings and other evidence, L. braziliensis braziliensis seems to be the predominant species transmitted in Três Braços.