scholarly journals USE OF THE POLYMERASE CHAIN REACTION FOR THE DIAGNOSIS OF ASYMPTOMATIC Leishmania INFECTION IN A VISCERAL LEISHMANIASIS-ENDEMIC AREA

2013 ◽  
Vol 55 (2) ◽  
pp. 101-104 ◽  
Author(s):  
Luciana Almeida Silva ◽  
Héctor Dardo Romero ◽  
Aline Fagundes ◽  
Nédia Nehme ◽  
Otávio Fernandes ◽  
...  

The diagnosis of asymptomatic infection with Leishmania (Leishmania) chagasi has become more important over recent years. Expansion of visceral leishmaniasis might be associated with other routes of transmission such as transfusion, congenital or even vector transmission, and subjects with asymptomatic infection are potential reservoirs. Moreover, the identification of infection may contribute to the management of patients with immunosuppressive conditions (HIV, transplants, use of immunomodulators) and to the assessment of the effectiveness of control measures. In this study, 149 subjects living in a visceral leishmaniasis endemic area were evaluated clinically and submitted to genus-specific polymerase chain reaction (PCR), serological testing, and the Montenegro skin test. Forty-nine (32.9%) of the subjects had a positive PCR result and none of them developed the disease within a follow-up period of three years. No association was observed between the results of PCR, serological and skin tests. A positive PCR result in subjects from the endemic area did not indicate a risk of progression to visceral leishmaniasis and was not associated with a positive result in the serological tests.

2020 ◽  
Vol 41 (1) ◽  
pp. 199
Author(s):  
Taiane Acunha Escobar ◽  
Gabriela Döwich ◽  
Letícia Carvalho Cantele ◽  
Geórgia Camargo Góss ◽  
Marcelo Lameiro Porciúncula ◽  
...  

Leishmaniasis is a neglected zoonotic disease caused by a variety of pathogenic Leishmania species. In the New World, especially in Brazil, visceral leishmaniasis (VL) is caused by Leishmania infantum. The pathogen can infect several animal species including dogs, foxes, rodents, primates, felines, equines and humans. Dogs act as the primary domestic reservoirs. This study aimed to use polymerase chain reaction (PCR) for detecting Leishmania infection in horses living in a canine visceral leishmaniasis (CVL) endemic region. DNA samples from horse peripheral blood were used to perform PCR. Templates were amplified using primers for the kinetoplast DNA (kDNA) minicircles, which were able to detect different species of Leishmania. In addition, primers for internal transcribed spacer (ITS) of ribosomal DNA were used for detection of Trypanosomatidae sp. Amongst the 75 (39%) positive PCR samples from total 192 samples, 21 samples were positive for kDNA and 63 samples were positive for either ITS, ITS1, or ITS2 gene markers. The kDNA PCR and sequencing allowed the detection of L. infantum in horse blood samples. To our knowledge, this is the first report of equine infection with L. infantum in Southern Brazil. These results proved that L. infantum could also infect horses in addition to humans and dogs, as well as in European countries. This conclusion emphasizes the urgent need to follow up investigation of the infection in these animals.


2013 ◽  
Vol 17 (3) ◽  
pp. 319-323
Author(s):  
Celia Maria Silva Pedrosa ◽  
Ricardo Arraes de Alencar Ximenes ◽  
Wendell Alexandre Pinheiro de Almeida ◽  
Eliana Maria Mauricio da Rocha

2019 ◽  
Vol 12 (3) ◽  
pp. 337-342 ◽  
Author(s):  
Tuba Dal ◽  
Soner Sertan Kara ◽  
Aytekin Cikman ◽  
Cigdem Eda Balkan ◽  
Ziya Cibali Acıkgoz ◽  
...  

2020 ◽  
pp. 1467-1475
Author(s):  
Antony D.M. Bryceson ◽  
Diana N.J. Lockwood

Leishmaniasis is caused by parasites of the genus Leishmania, which are transmitted to humans from human or animal reservoirs by the bites of phlebotomine sandflies. In places the disease is common and important, with perhaps 500,000 cases of visceral leishmaniasis and 1.5–2 million cases of cutaneous leishmaniasis worldwide each year. Diagnosis is by demonstration of leishmania organisms in tissue smears or biopsy material by microscopy, culture, or detecting leishmaniai DNA by polymerase chain reaction. As an imported disease, cutaneous leishmaniasis is common in travellers, military personnel, and immigrants coming from endemic areas, while the diagnosis of the less common visceral leishmaniasis is frequently overlooked. Prevention is by controlling reservoir hosts and sandfly vectors, or by avoiding bites by vectors. There is no vaccine.


Parasitology ◽  
2020 ◽  
Vol 147 (10) ◽  
pp. 1140-1148
Author(s):  
Fernanda do Carmo Magalhães ◽  
Samira Diniz Resende ◽  
Carolina Senra ◽  
Carlos Graeff-Teixeira ◽  
Martin Johannes Enk ◽  
...  

AbstractDue to the efforts to control schistosomiasis transmission in tropical countries, a large proportion of individuals from endemic areas present low parasite loads, which hinders diagnosis of intestinal schistosomiasis by the Kato-Katz (KK) method. Therefore, the development of more sensitive diagnostic methods is essential for efficient control measures. The aim was to evaluate the accuracy of a real-time polymerase chain reaction (RT-PCR) to detect Schistosoma mansoni DNA in fecal samples of individuals with low parasite loads. A cross-sectional population-based study was conducted in a rural community (n = 257) in Brazil. POC-CCA® was performed in urine and feces were used for RT-PCR. In addition, fecal exams were completed by 18 KK slides, saline gradient and Helmintex techniques. The combined results of the three parasitological tests detected schistosome eggs in 118 participants (45.9%) and composed the consolidated reference standard (CRS). By RT-PCR, 117 out of 215 tested samples were positive, showing 91.4% sensitivity, 80.2% specificity and good concordance with the CRS (kappa = 0.71). RT-PCR identified 86.9% of the individuals eliminating less than 12 eggs/g of feces, demonstrating much better performance than POC-CCA® (50.8%). Our results showed that RT-PCR is a valuable alternative for the diagnosis of intestinal schistosomiasis in individuals with very low parasite loads.


2014 ◽  
Vol 56 (5) ◽  
pp. 391-395 ◽  
Author(s):  
Herintha Coeto Neitzke-Abreu ◽  
Kárin Rosi Reinhold-Castro ◽  
Mateus Sabaini Venazzi ◽  
Regiane Bertin de Lima Scodro ◽  
Alessandra de Cassia Dias ◽  
...  

Sandflies transmit pathogens of leishmaniasis. The natural infection of sandflies by Leishmania (Viannia) was assessed in municipalities, in the state of Paraná, in Southern Brazil. Sandflies were collected with Falcão and Shannon traps. After dissection in search of flagellates in digestive tubes and identification of the species, female sandflies were submitted to the Multiplex Polymerase Chain Reaction (multiplex PCR) for detection of the fragment of the kDNA of Leishmania (Viannia) and the fragment from the IVS6 cacophony gene region of the phlebotomine insects. The analysis was performed in pools containing seven to 12 guts from females of the same species. A total of 510 female sandflies were analyzed, including nine Migonemyia migonei, 17 Pintomyia fischeri, 216 Nyssomyia neivai, and 268 Nyssomyia whitmani. Although none of the females was found naturally infected by flagellates through dissection, the fragment of DNA from Leishmania (Viannia) was shown by multiplex PCR in one sample of Ny. neivai (0.46%) and three samples of Ny. whitmani (1.12%). It was concluded that Ny. neivai and Ny. whitmani are susceptible to Leishmania infection, and that multiplex PCR can be used in epidemiological studies to detect the natural infection of the sandfly vector, because of its sensitivity, specificity and feasibility.


2017 ◽  
Vol 63 (02/2017) ◽  
Author(s):  
Kazumi Umeki ◽  
Kunihiko Umekita ◽  
Yuuki Hashikura ◽  
Ikuo Yamamoto ◽  
Kazuyoshi Kubo ◽  
...  

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