Detection of Internal Transcribed Spacer 1 and hsp70 Genetic Markers Using Restriction Fragment Length Polymorphisms and Sequencing in Identification of Leishmania Species Causing Tegumentary Leishmaniasis in Brazil.

The identification of Leishmania species that cause tegumentary leishmaniasis (TL) is important for taxonomic and prognostic purposes. Molecular analysis using different Leishmania genomic targets is the most useful method for identifying Leishmania species. Therefore, we evaluated the performance of ribosomal RNA internal transcribed spacer 1 (ITS1) and heat shock protein (hsp70) genetic markers by polymerase chain reaction (PCR), followed by restriction fragment length polymorphism analysis (RFLP) and sequencing, for identification of Leishmania species. Samples from 84 Brazilian patients were amplified. Internal transcribed spacer 1 PCR followed by RFLP (HaeIII) [ITS1-RFLP (HaeIII)] identified 46.4% (39/84) of the samples as compatible with the Viannia subgenus. Internal transcribed spacer 1 PCR followed by sequencing (ITS1-sequencing) identified Leishmania (Viannia) braziliensis in 91.7% (77/84) of the TL samples, Leishmania (Leishmania) amazonensis in 3.6% (3/84), L. (V.) guyanensis in 2.4% (2/84), and L. (L.) infantum in 1.2% (1/84). One of the samples showed the same proportion of similarity with L. (V.) guyanensis and L. (V.) panamensis. hsp70 nested PCR followed by RFLP (HaeIII) [nested hsp70-RFLP (HaeIII)] identified 91.7% (77/84) of the samples as compatible with L. (V.) braziliensis/L. (V.) naiffi, 3.6% (3/84) with L. (L.) amazonensis, 1.2% (1/84) with L. (L.) infantum, and 3.6% (3/84) with L. (V.) guyanensis. hsp70 PCR followed by sequencing (hsp70-sequencing) identified L. (V.) braziliensis in 91.7% (77/84) of the TL samples, L. (L.) amazonensis in 3.6% (3/84), L. (V.) guyanensis in 3.6% (3/84), and L. (L.) infantum in 1.2% (1/84). Our findings clearly showed that nested hsp70-RFLP (HaeIII) is better than ITS1-RFLP (HaeIII) and that ITS1 or hsp70 PCR followed by sequencing was adequate for identifying Leishmania species. We also found that Leishmania (Viannia) braziliensis is the most common species causing TL in Brazil. Therefore, sequencing multiple target genes such as ITS1 and hsp 70 is more accurate than RFLP for identifying Leishmania species.

Genetic variability of Leishmania (Leishmania) infantum causing human visceral leishmaniasis in the Southeastern Brazil.

Leishmania infantum is a protozoan that causes visceral leishmaniasis (VL) in the Americas and some regions of Europe. The disease is mainly characterized by hepatosplenomegaly and fever, and can be fatal. Factors related to the host and parasite can contribute to the transmission of Leishmania and the clinical outcome. The intraspecific genetic variability of L. infantum strains may be one of these factors. In this study, we evaluated the genetic variability of L. infantum obtained from bone marrow smear slides from patients in the Sao Paulo State, Brazil. For this, the minicircle of the kDNA hypervariable region was used as target by Sanger sequencing. By analyzing the similarity of the nucleotides and the maximum likelihood tree (Fasttree), we observed a high similarity (98%) among samples. Moreover, we identified four different profiles of L. infantum. In conclusion, L. infantum strains from Sao Paulo State, Brazil, showed low diversity measured by minicircle of the kDNA hypervariable region.

Genetic variability of Leishmania (Leishmania) infantum causing human visceral leishmaniasis in the Southeastern Brazil

ABSTRACT Leishmania infantum is a protozoan that causes visceral leishmaniasis (VL) in the Americas and some regions of Europe. The disease is mainly characterized by hepatosplenomegaly and fever, and can be fatal. Factors related to the host and parasite can contribute to the transmission of Leishmania and the clinical outcome. The intraspecific genetic variability of L. infantum strains may be one of these factors. In this study, we evaluated the genetic variability of L. infantum obtained from bone marrow smear slides from patients in the Sao Paulo State, Brazil. For this, the minicircle of the kDNA hypervariable region was used as target by Sanger sequencing. By analyzing the similarity of the nucleotides and the maximum likelihood tree (Fasttree), we observed a high similarity (98%) among samples. Moreover, we identified four different profiles of L. infantum. In conclusion, L. infantum strains from Sao Paulo State, Brazil, showed low diversity measured by minicircle of the kDNA hypervariable region.

Disparity between scientific accomplishment and biotechnology availability in Brazil.

Despite being among the world's leaders in scientific output, Brazil ranks 66th among countries in the production of reagents and supplies needed for state-of-the-art scientific analyses. The production of needed reagents and equipment for experimental analyses and patient diagnostics is sorely lacking within Brazil and explicit in this pandemic period caused by SARS-CoV-2. A significant fraction of resources from Brazilian funding agencies is now being transferred to companies in other countries for the purchase of essential scientific-related products. Is this sustainable? Therefore it is necessary to draw the attention of all the world and Brazilian society about this situation.

Unusual manifestation of genital cutaneous leishmaniasis in an immunocompetent patient from São Paulo, Brazil: A case report.

A 31-year-old male patient developed an ulcer on the glans penis that evolved for three months without healing. We diagnosed it as leishmaniasis using polymerase chain reaction. No immunosuppression or associated diseases were observed. The patient was treated with meglumine antimoniate that cured the lesion in a month post-treatment. Here, we report this case of cutaneous leishmaniasis lesion at the unusual location of glans penis in an immunocompetent individual. The lesion likely developed due to the bite of a vector, highlighting the need for considering cutaneous leishmaniasis among differential diagnosis of sexually transmitted diseases in areas endemic for leishmaniasis.

A sensitive and reliable quantitative immunohistochemistry technique to evaluate the percentage of Trypanosoma cruzi-infected tissue area.

Quantification of parasites in the context of Chagas disease is required to monitor the treatment with benznidazole, disease-associated cardiomyopathies and graft rejection after heart transplantation. As parasitological exams lack sensitivity, Real Time Polymerase Chain Reaction (rt-PCR) has emerged to evaluate the parasite load in blood samples and cardiac biopsies. However, despite its higher sensitivity, rt-PCR does not provide information on the location and distribution of amastigote nests within infected tissues, the characterization of inflammatory infiltrates or changes to tissue architecture. On the contrary, a sensitive immunohistochemistry technique (IHC) could fill these gaps. In the present study, a quantitative IHC exam was standardized and validated by testing adipose and cardiac tissues of experimentally infected mice containing variable parasite load levels of T. cruzi assessed by a sensitive Sybr Green rt-PCR with kDNA primers. Tissues were divided into four groups according to the parasite load: group A- 100 parasites/50 ng of DNA; group B -10 parasites; group C - around 1 parasite and group D - less than 1 parasite/50 ng/DNA. IHC was able to detect T. cruzi in the four groups, even in group D tissues containing fractions of a single parasite/50 ng of DNA sample according to rt-PCR. In conclusion, a highly sensitivity and reliable quantitative immunohistochemistry technique was developed and is proposed to estimate the percentage of T. cruzi-infected tissue area in chagasic patients presenting with cardiomyopathies, as a complementary test to rt-PCR.

Unusual manifestation of genital cutaneous leishmaniasis in an immunocompetent patient from São Paulo, Brazil: A case report

Abstract A 31-year-old male patient developed an ulcer on the glans penis that evolved for three months without healing. We diagnosed it as leishmaniasis using polymerase chain reaction. No immunosuppression or associated diseases were observed. The patient was treated with meglumine antimoniate that cured the lesion in a month post-treatment. Here, we report this case of cutaneous leishmaniasis lesion at the unusual location of glans penis in an immunocompetent individual. The lesion likely developed due to the bite of a vector, highlighting the need for considering cutaneous leishmaniasis among differential diagnosis of sexually transmitted diseases in areas endemic for leishmaniasis.

Nitro-Heterocyclic compounds induce apoptosis-like effects in Leishmania (L). amazonensis promastigotes.

BACKGROUND: Three drugs - pentavalent antimonials, amphotericin B and pentamidine - are currently used for leishmaniasis treatment. They are administered for long periods, only parenterally, and have high cardiac, renal and hepatic toxicities. Therefore, the investigation of new compounds is required. Nitro-heterocyclic derivatives have been used as possible drug candidates to treat diseases caused by trypanosomatids. METHODS: Leishmania (L.) amazonensis promastigotes (MHO/BR/73/M2269), maintained in the Laboratório de Soroepidemiologia - Instituto de Medicina Tropical- USP, were exposed to five nitroheterocyclic derivatives, with differences at phenyl-ring position 4: BSF-C4H9, BSF-H, BSF-NO2, BSF-CH3 and BSF-Cl, for 48 hours. After analyzing viability (MTT assay), we evaluated cellular-morphology activity of compounds by transmission electron microscopy (TEM) and measurement of apoptosis (phosphatidylserine expression) by flow cytometry. RESULTS: EC50 of amphotericin B and BSF-CH3 were 0.50 (M and 0.39 (M respective. Other nitro-heterocyclic compounds presented EC50 higher than amphotericin B. All compounds showed greater AV- and PI-positive expression than amphotericin B at 100 (M, except BSF-NO2. TEM showed complete nuclear disfigurement with 100 (M of BSF-NO2, 25 and 6.25 (M of BSF-H, and 6.25 (M BSF-Cl; presence of vesicles within the flagellar pocket with 25 (M BSF-H; alteration of the kinetoplast with 25 (M BSF-C4H9, 25 (M of BSF-H, 6.25 (M BSF-CH3 and 6.25 (M of BSF-Cl. CONCLUSIONS: Nitro-heterocyclic compounds have shown activity against promastigotes of L. amazonensis, at lower concentrations. However, improvement of compound scaffolds are needed to assist the elucidation of the mechanism of action and to achieve greater activity.

Mitochondrial and satellite real time-PCR for detecting T. cruzi DTU II strain in blood and organs of experimentally infected mice presenting different levels of parasite load.

The choice of cost-effective molecular methods for diagnosing and monitoring of Chagas disease before and after treatment is crucial in endemic countries with high patients' demand and limited financial resources. To this end, a kDNA was compared to a satellite real-time quantitative PCR (sat-qPCR), both amplifications using Sybr Green instead of Taqman hydrolysis probes. Non-isogenic Swiss albino mice were infected with a small inoculum of the highly virulent and partially resistant to benznidazole Y strain, belonging to T. cruzi discrete typing unit II (DTU-II) that predominates in Atlantic and Central Brazil. DNA from EDTA-blood samples and 10 organs of mice containing high, moderate and low parasite load levels were extracted by a highly used commercial kit and tested in triplicate, showing no disagreements between the two qPCRs. The melting temperature of positive samples was 79.8 °C ±â€¯1 °C for satellite-DNA and 78.1 °C ±â€¯1 °C for kDNA. DNA from genetically-related parasites such as Leishmania sp. showed no cross-reactions, but the sympatric T. rangeli was detected by both qPCRs, more effectively by kDNA than the satellite system, which required the equivalent of 50 parasites to give a positive result. Samples from infected mice, regardless of the type of biological matrix (blood or organ samples) or the parasite load gave positive results by both qPCRs. The sensitivity of sat-qPCR was 2 × 10-3 parasite or 240 target copies, and for kDNA, 2 × 10-4 parasite or 24 target copies. Regarding repeatability and reproducibility, the coefficient of variation (CV) was always < 25% in both assays; linearity of sat-qPCR was 0.991 (±0.002) and 0.991 (±0.008) for kDNA qPCR. In most collection times, the median Ct values found in blood and organs provided by sat-DNA and kDNA qPCRs were similar. In conclusion, although kDNA qPCR achieved a better analytical sensitivity, sat-qPCR gave better specificity results. Nevertheless, further research is intended to test other T. cruzi DTUs and chagasic patients' samples before these cost-effective techniques are incorporated into diagnostic routines.

Nitro-Heterocyclic compounds induce apoptosis-like effects in Leishmania (L). amazonensis promastigotes

Abstract Background: Three drugs - pentavalent antimonials, amphotericin B and pentamidine - are currently used for leishmaniasis treatment. They are administered for long periods, only parenterally, and have high cardiac, renal and hepatic toxicities. Therefore, the investigation of new compounds is required. Nitro-heterocyclic derivatives have been used as possible drug candidates to treat diseases caused by trypanosomatids. Methods: Leishmania (L.) amazonensis promastigotes (MHO/BR/73/M2269), maintained in the Laboratório de Soroepidemiologia - Instituto de Medicina Tropical- USP, were exposed to five nitroheterocyclic derivatives, with differences at phenyl-ring position 4: BSF-C4H9, BSF-H, BSF-NO2, BSF-CH3 and BSF-Cl, for 48 hours. After analyzing viability (MTT assay), we evaluated cellular-morphology activity of compounds by transmission electron microscopy (TEM) and measurement of apoptosis (phosphatidylserine expression) by flow cytometry. Results: EC50 of amphotericin B and BSF-CH3 were 0.50 (M and 0.39 (M respective. Other nitro-heterocyclic compounds presented EC50 higher than amphotericin B. All compounds showed greater AV- and PI-positive expression than amphotericin B at 100 (M, except BSF-NO2. TEM showed complete nuclear disfigurement with 100 (M of BSF-NO2, 25 and 6.25 (M of BSF-H, and 6.25 (M BSF-Cl; presence of vesicles within the flagellar pocket with 25 (M BSF-H; alteration of the kinetoplast with 25 (M BSF-C4H9, 25 (M of BSF-H, 6.25 (M BSF-CH3 and 6.25 (M of BSF-Cl. Conclusions: Nitro-heterocyclic compounds have shown activity against promastigotes of L. amazonensis, at lower concentrations. However, improvement of compound scaffolds are needed to assist the elucidation of the mechanism of action and to achieve greater activity.

Reactivation of cutaneous and mucocutaneous tegumentary leishmaniasis in rheumatoid arthritis patients: an emerging problem?

Rheumatoid arthritis (RA) is a chronic condition that is frequent in patients living in tropical areas exposed to leishmaniasis. RA therapy involves immunosuppressant drugs such as methotrexate (MTX), monoclonal antibodies (mAbs) and prednisone. We report an unusual presentation of cutaneous (CL) or mucocutaneous leishmaniasis (ML) in RA patients from an endemic area of leishmaniasis. A 51-year-old woman noted a cutaneous ulcer on her left ankle during MTX and prednisone RA therapy. Initially diagnosed as a venous stasis ulcer, the aspirate of the injury revealed the presence of Leishmania DNA. A 73-year-old woman presenting non-ulcerated, infiltrated and painful erythematous nodules inside her nostrils while receiving MTX, anti-TNF mAb, and prednisone for RA, had also the aspirate of injuries showing the presence of Leishmania DNA. Both patients healed after the therapy with liposomal amphotericin. The RA therapy has changed to low-dose prednisone, without further reactivation episodes. Both cases suggest that CL or ML can reactivate after administration of an immunosuppressant for RA treatment. Therefore, immunosuppressive treatments for RA should be carefully prescribed in patients from endemic areas or with a history of CL and ML.

Reactivation of cutaneous and mucocutaneous tegumentary leishmaniasis in rheumatoid arthritis patients: an emerging problem?

ABSTRACT Rheumatoid arthritis (RA) is a chronic condition that is frequent in patients living in tropical areas exposed to leishmaniasis. RA therapy involves immunosuppressant drugs such as methotrexate (MTX), monoclonal antibodies (mAbs) and prednisone. We report an unusual presentation of cutaneous (CL) or mucocutaneous leishmaniasis (ML) in RA patients from an endemic area of leishmaniasis. A 51-year-old woman noted a cutaneous ulcer on her left ankle during MTX and prednisone RA therapy. Initially diagnosed as a venous stasis ulcer, the aspirate of the injury revealed the presence of Leishmania DNA. A 73-year-old woman presenting non-ulcerated, infiltrated and painful erythematous nodules inside her nostrils while receiving MTX, anti-TNF mAb, and prednisone for RA, had also the aspirate of injuries showing the presence of Leishmania DNA. Both patients healed after the therapy with liposomal amphotericin. The RA therapy has changed to low-dose prednisone, without further reactivation episodes. Both cases suggest that CL or ML can reactivate after administration of an immunosuppressant for RA treatment. Therefore, immunosuppressive treatments for RA should be carefully prescribed in patients from endemic areas or with a history of CL and ML.

Could kDNA-PCR in peripheral blood replace the examination of bone marrow for the diagnosis of visceral leishmaniasis?

The aim of this study was to evaluate whether the molecular (kDNA-PCR) and parasitological diagnosis in peripheral blood (PB) could replace the invasive and painful bone marrow collection (BM) in the diagnosis of visceral leishmaniasis (VL). PB from suspected VL patients was evaluated by parasitological and molecular techniques using as the gold standard (GS) a combination of clinical, epidemiological, and immunochromatographic test (PB-rK39) results and parasitological examination of BM. Based on the GS, 38 samples from 32 patients were grouped: Group 1, 20 samples of VL cases, and Group 2, 18 samples of non-VL cases. In order to evaluate the parasitological and molecular techniques in PB, the samples were examined. From Group 1, PB kDNA-PCR was positive in 20 samples and in 19 of 20 in BM kDNA-PCR examination. However, the parasitological examination of buffy coat was insensitive, being able to detect only 4 cases from Group 1. All samples from Group 2 were negative. We concluded that, for the diagnosis of visceral leishmaniasis, the parasitological examination of peripheral blood was not useful; however, molecular diagnosis by kDNA-PCR, performed in peripheral blood, could be useful to replace the parasitological examination of bone marrow

Post-kala-azar dermal leishmaniasis and leprosy: case report and literature review.

BACKGROUND: Post-kala-azar dermal leishmaniasis (PKDL) is a dermal complication of visceral leishmaniasis (VL), which may occur after or during treatment. It has been frequently reported from India and the Sudan, but its occurrence in South America has been rarely reported. It may mimic leprosy and its differentiation may be difficult, since both diseases may show hypo-pigmented macular lesions as clinical presentation and neural involvement in histopathological investigations. The co-infection of leprosy and VL has been reported in countries where both diseases are endemic. The authors report a co-infection case of leprosy and VL, which evolved into PKDL and discuss the clinical and the pathological aspects in the patient and review the literature on this disease. CASE PRESENTATION: We report an unusual case of a 53-year-old female patient from Alagoas, Brazil. She presented with leprosy and a necrotizing erythema nodosum, a type II leprosy reaction, about 3 month after finishing the treatment (MDT-MB) for leprosy. She was hospitalized and VL was diagnosed at that time and she was successfully treated with liposomal amphotericin B. After 6 months, she developed a few hypo-pigmented papules on her forehead. A granulomatous inflammatory infiltrate throughout the dermis was observed at histopathological examination of the skin biopsy. It consisted of epithelioid histiocytes, lymphocytes and plasma cells with the presence of amastigotes of Leishmania in macrophages (Leishman's bodies). The diagnosis of post-kala-azar dermal leishmaniasis was established because at this time there was no hepatosplenomegaly and the bone marrow did not show Leishmania parasites thus excluding VL. About 2 years after the treatment of PKDL with liposomal amphotericin B the patient is still without PKDL lesions. CONCLUSION: Post-kala-azar dermal leishmaniasis is a rare dermal complication of VL that mimics leprosy and should be considered particularly in countries where both diseases are endemic. A co-infection must be seriously considered, especially in patients who are non-responsive to treatment or develop persistent leprosy reactions as those encountered in the patient reported here.

USEFULNESS OF kDNA PCR IN THE DIAGNOSIS OF VISCERAL LEISHMANIASIS REACTIVATION IN CO-INFECTED PATIENTS / Utilidade da kDNA PCR no diagnostico de reativacao de leishmaniose visceral em pacientes co-infectados sintomaticos

SUMMARY It is important to develop new methods for diagnosing relapses in the co-infection of visceral leishmaniasis (VL) and HIV to enable earlier detection using less invasive methods. We report a case of a co-infected patient who had relapses after VL treatment, where the qualitative kDNA PCR showed a good performance. The kDNA PCR seems to be a useful tool for diagnosing VL and may be a good marker for predicting VL relapses after treatment of co-infected patients with clinical symptoms of the disease. .

RESUMO É importante a pesquisa de novos métodos laboratoriais para o diagnóstico de recidivas em casos de co-infecção leishmaniose visceral (LV) e vírus da imunodeficiência humana (HIV), que permitam o diagnóstico precoce das recidivas, utilizando métodos menos invasivos. Descrevemos aqui, o caso de paciente co-infectada que apresentou recidivas após o tratamento da LV e onde a PCR qualitativa demonstrou bom desempenho. A kDNA PCR parece ser ferramenta útil para o diagnóstico de recidivas de LV após o tratamento em pacientes co-infectados com sintomas clínicos da doença. .

Usefulness of kDNA PCR in the diagnosis of visceral leishmaniasis reactivation in co-infected patients.

It is important to develop new methods for diagnosing relapses in the co-infection of visceral leishmaniasis (VL) and HIV to enable earlier detection using less invasive methods. We report a case of a co-infected patient who had relapses after VL treatment, where the qualitative kDNA PCR showed a good performance. The kDNA PCR seems to be a useful tool for diagnosing VL and may be a good marker for predicting VL relapses after treatment of co-infected patients with clinical symptoms of the disease.

Análise de técnicas parasitológicas utilizadas no seguimento de pacientes com doença de chagas e tratados por meio do transplante cardíaco / Analysis of parasitological techniques in the monitoring of patients with Chagas disease and treated by heart transplantation

Este estudo teve como objetivo analisar a função da hemocultura, do xenodiagnóstico e do creme leucocitário no acompanhamento e diagnóstico de possível reativação em pacientescrônicos tratados por meio do transplante de coração. Foram examinadas 70 amostras das quais15,7por cento (11/70) se mostraram positivas, sendo 8,5por cento (6/70) na hemocultura e 12,8por cento (9/70) noxenodiagnóstico. Apresentaram concordância nos dois métodos quatro amostras (36,36por cento). Nãohouve positividade no creme leucocitário. Os achados corroboram informações sobre a superiorsensibilidade do xenodiagnóstico em relação à hemocultura. A amostra do paciente 20, positiva noxenodiagnóstico (décimo quinto dia) e que apresentou miocardite com ninhos de amastigotas 15 dias antes dadetecção laboratorial, sinaliza a importância da leitura precoce dos exames parasitológicos comopreditivos de possível reativação da doença.