Correlations between tissue parasite load and common clinical signs in dogs naturally infected by Leishmania infantum

2021 ◽  
Vol 291 ◽  
pp. 109368
Author(s):  
Úrsula Maira Russo Chagas ◽  
Daniel Moreira de Avelar ◽  
Andreza Pain Marcelino ◽  
Gustavo Fontes Paz ◽  
Célia Maria Ferreira Gontijo
PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0247560
Author(s):  
Valéria da Costa Oliveira ◽  
Artur Augusto Velho Mendes Junior ◽  
Luiz Claudio Ferreira ◽  
Tatiana Machado Quinates Calvet ◽  
Shanna Araujo dos Santos ◽  
...  

In canine leishmaniosis caused by the protozoan Leishmania infantum, little is known about how co-infections with or co-seropositivities for other pathogens can influence aggravation of this disease. Therefore, the objectives of this study were to evaluate the frequency of co-infections with or co-seropositivities for certain pathogens in dogs seropositive for L. infantum and their relationship with clinical signs, histological changes and L. infantum load. Sixty-six L. infantum-seropositive dogs were submitted to clinical examination, collection of blood and bone marrow, culling, and necropsy. Antibodies against Anaplasma spp., Borrelia burgdorferi sensu lato, Ehrlichia spp. and Toxoplasma gondii and Dirofilaria immitis antigens were investigated in serum. Samples from different tissues were submitted to histopathology and immunohistochemistry for the detection of Leishmania spp. and T. gondii. Quantitative real-time PCR was used to assess the L. infantum load in spleen samples. For detection of Coxiella burnetii, conventional PCR and nested PCR were performed using bone marrow samples. All 66 dogs tested positive for L. infantum by qPCR and/or culture. Fifty dogs (76%) were co-seropositive for at least one pathogen: T. gondii (59%), Ehrlichia spp., (41%), and Anaplasma spp. (18%). Clinical signs were observed in 15 (94%) dogs monoinfected with L. infantum and in 45 (90%) dogs co-seropositive for certain pathogens. The L. infantum load in spleen and skin did not differ significantly between monoinfected and co-seropositive dogs. The number of inflammatory cells was higher in the spleen, lung and mammary gland of co-seropositive dogs and in the mitral valve of monoinfected dogs. These results suggest that dogs infected with L. infantum and co-seropositive for certain pathogens are common in the region studied. However, co-seropositivities for certain pathogens did not aggravate clinical signs or L. infantum load, although they were associated with a more intense inflammatory reaction in some organs.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
William de Oliveira Kost ◽  
Sandro Antonio Pereira ◽  
Fabiano Borges Figueiredo ◽  
Artur Augusto Velho Mendes Junior ◽  
Maria de Fátima Madeira ◽  
...  

Abstract Background Zoonotic visceral leishmaniasis is caused by the protozoan Leishmania infantum and is highly lethal in humans and dogs if left untreated. The frequency of this parasite and associated histological changes in the pancreas of dogs are poorly studied. Therefore, the objectives of this study were to evaluate the frequency of detection and load of amastigotes in the pancreas of L. infantum-seropositive dogs and to identify the clinical signs and histological changes associated with parasitism of this organ. Methods One hundred forty-three dogs from an endemic area in Brazil that tested seropositive for L. infantum were studied. The dogs were clinically examined, killed, and necropsied between 2013 and 2014. One fragment of the pancreas was randomly collected for histopathology and immunohistochemistry, and spleen and bone marrow were collected for culture. Results Leishmania amastigotes were detected in the pancreas of 22 dogs (15.4%) by immunohistochemistry, all exhibiting L. infantum parasitism in the spleen and/or bone marrow. Poor body condition and cachexia were only associated with infection of the pancreas with Leishmania spp. (p = 0.021) and were found in 40.9% of dogs with pancreatic infection. Anorexia, vomiting, and/or diarrhea were observed in 9.2% of dogs with pancreatitis. The median parasite load in the pancreas was 1.4 infected macrophages/mm2. Pancreatic histological changes and their frequencies were: granulomatous pancreatitis (28.0%), lymphoplasmacytic pancreatitis (23.8%), acinar cell degeneration (6.3%), fibrosis (5.6%), hemorrhage (2.1%), eosinophilic pancreatitis (0.7%), suppurative pancreatitis (0.7%), and necrosis (0.7%). Conclusions The present results demonstrate that L. infantum is one of the etiological agents of chronic pancreatitis in dogs; however, the frequency of detection and parasite load are low in this organ. The lack of an association of poor body condition and cachexia with pancreatitis and the low frequency of clinical signs commonly associated with pancreatitis suggest that a significant portion of the organ is not affected by this parasite. On the other hand, the association of poor body condition and cachexia with concomitant infection of the pancreas, spleen, and/or bone marrow with this parasite suggests that these manifestations are the result of a more advanced stage of canine visceral leishmaniasis. Graphic abstract


1999 ◽  
Vol 43 (1) ◽  
pp. 172-174 ◽  
Author(s):  
Jean-Pierre Gangneux ◽  
Michael Dullin ◽  
Annie Sulahian ◽  
Yves Jean-Francois Garin ◽  
Francis Derouin

ABSTRACT In a murine model of Leishmania infantum visceral leishmaniasis, metronidazole, ketoconazole, fluconazole, itraconazole, and terbinafine were less effective than antimonial agents in reducing hepatic parasite load. Ketoconazole potentiated the effect of meglumine antimoniate reference therapy through its marked activity against spleen infection.


2018 ◽  
Vol 46 (1) ◽  
pp. 7
Author(s):  
Francina Dos Santos Silva ◽  
Simone Carvalho dos Santos Cunha ◽  
Andrea Regina de Souza Baptista ◽  
Vivian Dos Santos Baptista ◽  
Kássia Valéria Gomes Coelho da Silva ◽  
...  

Background: Sporotrichosis is a zoonosis caused by fungi of the Sporothrix schenckii complex. Cats have important zoonotic potential due to the high parasite load found in the cutaneous lesions. Refractory cases to antifungal therapy are increasing, becoming a public health problem. Miltefosine is a drug with high in vitro activity against Sporothrix brasiliensis. However, this efficacy has not been confirmed in vivo yet and administration has not been studied in the feline species. This study aimed to evaluate the effectiveness and safety of miltefosine administration in cats with resistant sporotrichosis.Materials, Methods & Results: Ten cats with refractory sporotrichosis were included in this study. Inclusion criteria were previous diagnosis for sporotrichosis associated with therapy with oral antifungals (itraconazole and/or potassium iodide) for more than one year, followed by one of these conditions: incomplete clinical remission, worsening of disease during treatment or recurrence after conventional treatment. Cats underwent clinical and dermatological examinations. Data on lifestyle and previous treatments were provided by the owners. Fungal culture and histochemical techniques were performed in all cats before miltefosine treatment. Blood samples were collected before and during the study for laboratory tests, such as blood count, blood urea nitrogen (BUN), serum creatinine, alanine aminotransferase (ALT) and alkaline phosphatase, as well as serology for Feline Immunodeficiency (FIV) and Feline Leukemia (FeLV). Miltefosine was prescribed at a dosage of 2 mg/kg orally every 24 h. The animals were monitored by phone during the whole process and reassessed on days 0, 15, 30 and 45 of the treatment. Out of 10 cats, lesions were present on the nose in nine, ears in four, periocular areas in one and limbs in four. One cat received treatment for 45 days, six for 30 days, one for 21 days, one for 15 days and one for 3 days. One cat showed no response to the treatment and nine showed disease progression. Hyporexia and weight loss were the most frequent clinical signs related to miltefosine treatment, followed by sialorrhea, vomiting and diarrhea. Few adverse effects on hematology and biochemistry (mainly renal and hepatic parameters) were observed during the study. Hematocrit decrease was observed in four animals. However, only one cat had hematocrit decrease below normal values (anemia), which was already present before miltefosine administration. Other cats had a decrease of five points. Three cats showed elevation in leucometria and four in plasma protein. In relation to renal and hepatic biochemistry, one animal showed a BUN increase and another one showed a transient increase in ALT. Two animals started the treatment with increased ALT but had no problems during the study and values decreased even during the miltefosine administration.Discussion: Although two cats showed sialorrhea, most owners did not report difficulty in administering the drug orally, representing an advantage of this medication. Weight loss, secondary to gastrointestinal changes, was the most clinically relevant alteration. The most frequent hematological alteration was hematocrit decrease and only the animal that started the study with 20% hematocrit ended the study with anemia. Renal and hepatic parameters were not significant in the cats of this study. Miltefosine did not lead to sporotrichosis remission in this small population of cats, which reveals that, despite its in vitro efficacy against Sporothrix spp., the drug is not effective in vivo in the feline species. Further studies are needed to investigate the efficacy of this drug in a larger number of cats, and possible reasons for its in vivo ineffectiveness.


2021 ◽  
Vol 49 ◽  
Author(s):  
Adam Leal-Lima ◽  
Tiago Cunha Ferreira ◽  
Társsila Mara Vieira Ferreira ◽  
Pedro Covas Coelho ◽  
Diana Célia Sousa Nunes-Pinheiro

 Background: Canine vector borne diseases (CVBD) are common in tropical countries where the climate favors arthropods abundance. Comorbidity with one or more CVBD are reported as clinical complication and worsen prognostic. Canine visceral leishmaniosis (CanL) is an endemic zoonotic disease in Brazil caused by Leishmania infantum, with several restrictions to canine treatment and suggestion of reservoirs euthanasia for disease control. Heart worm (HW) is a helminthic disease caused by Dirofilaria immitis infection in dogs. It is a chronic heart disease, which can lead to death by congestive heart failure. Canine ehrlichiosis (CE) is caused by Ehrlichia canis bacterial infection with a zoonotic potential and fatal to dogs in acute and chronic presentations. Exposed the above, this study aims to describe a successful treatment and management of a dog with CanL, CE, and HW comorbidity. Case: A 3-year-old male uncastrated black Labrador dog, weighing 35 kg, was admitted to the veterinary clinic due to immunochromatographic CanL positive test performed by municipal zoonosis control center active surveillance in August 2014. Clinical exam showed a mild shedding, intermittent eye white/yellow discharge and popliteal lymph nodes enlargement. After positive for CanL, veterinary requested more laboratorial exams. IFAT and ELISA were positive for CanL, blood smear showed presence of microfilaria, and bone marrow cytology showed Ehrlichia spp. morulae and microfilaria. Initial treatment prescribed was oral doxycycline, omeprazole, ranitidine, and domperidone for 30 days, and allopurinol and ivermectin until further recommendation. Additionally, repellent collar, repellent spray and vitamin supplement was indicated. After first month, marbofloxacin for 30 days and three doses of immune stimulant protocol were administrated. After three months of treatment, dog still positive for heartworm, ehrlichiosis, and CanL. Doxycycline protocol was repeated. Dog became consistently negative for all pathogens one year later with persistent thrombocytopenia but without clinical signs, ergo allopurinol and ivermectin were discontinued. After four years of follow up, the animal had an acute pancreatitis and died, with unremarkable total blood count and negative for all pathogens. Discussion: CVBD coinfections are commonly reported as worsen prognostic in endemic regions. The pathogens reported here share a host immunomodulation competence. L. infantum and Ehrlichia spp.downregulates Th1 response, whereas D. immitis increase as Th2 profile. The therapeutic protocol was iniciated by staging CanL. Since the patient had clinical signs, allopurinol was prescribed as a well-established drug for CanL. Marbofloxacin was added due to its high safety drug in clinical improvement of infected dogs with and without renal disease and in vitro effectiveness against L. infantum. Domperidone was used to promote Th1 cytokine profile as INF-γ, IL-2, IL-12, and TNF-α. We used an immunostimulant protocol to favor polarization to the Th1 profile comprised by 30 days of domperidone protocol followed by a vaccine and an immunomodulator. Doxycycline was used successfully for Ehrlichia spp. and HE clearance after two treatment courses and one year of ivermectin every 15 days. The animal presented intermittent coughing episodes on the first treatment course, but no medical intervention was needed besides exercise restriction. Our report shows the successful management of one dog with CanL, CE and HE comorbidity. This success was possible due to early detection and good therapeutic choice.Keywords: canine visceral leishmaniosis, coinfection, Dirofilaria immitis, Erhlichia canis, Leishmania infantum, treatment.


2014 ◽  
Vol 82 (9) ◽  
pp. 3704-3712 ◽  
Author(s):  
Maria M. Figueiredo ◽  
Beatriz Deoti ◽  
Izabela F. Amorim ◽  
Aldair J. W. Pinto ◽  
Andrea Moraes ◽  
...  

ABSTRACTUsing flow cytometry, we evaluated the frequencies of CD4+and CD8+T cells and Foxp3+regulatory T cells (Tregs) in mononuclear cells in the jejunum, colon, and cervical and mesenteric lymph nodes of dogs naturally infected withLeishmania infantumand in uninfected controls. All infected dogs showed chronic lymphadenitis and enteritis. Despite persistent parasite loads, no erosion or ulcers were evident in the epithelial mucosa. The colon harbored more parasites than the jejunum. Frequencies of total CD4+, total Foxp3, and CD4+Foxp3+cells were higher in the jejunum than in the colon. Despite negative enzyme-linked immunosorbent assay (ELISA) serum results for cytokines, levels of interleukin-10 (IL-10), gamma interferon (IFN-γ), transforming growth factor beta (TGF-β), and tumor necrosis factor alpha (TNF-α) were higher in the jejunum than in the colon for infected dogs. However, IL-4 levels were higher in the colon than in the jejunum for infected dogs. There was no observed correlation between clinical signs and histopathological changes or immunological and parasitological findings in the gastrointestinal tract (GIT) of canines with visceral leishmaniasis. However, distinct segments of the GIT presented different immunological and parasitological responses. The jejunum showed a lower parasite load, with increased frequencies and expression of CD4, Foxp3, and CD8 receptors and IL-10, TGF-β, IFN-γ, and TNF-α cytokines. The colon showed a higher parasite load, with increasing expression of IL-4.Leishmania infantuminfection increased expression of CD4, Foxp3, IL-10, TGF-β, IFN-γ, and TNF-α and reduced CD8 and IL-4 expression in both the jejunum and the colon.


2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Claudia Momo ◽  
Ana Paula Prudente Jacintho ◽  
Pamela Rodrigues Reina Moreira ◽  
Danísio Prado Munari ◽  
Gisele Fabrino Machado ◽  
...  

The aim of this study was to evaluate the most frequent lesions in the bone marrow of dogs naturally infected byLeishmania (Leishmania) chagasi.Thirty-three dogs sacrificed at the Zoonosis Control Center of Araçatuba, a municipality endemic for visceral leishmaniasis (VL), were used. The animals were classified as asymptomatic, oligosymptomatic, and symptomatic groups. At the necropsy, bone marrow samples were collected from the femur, fixed, processed, and stained with hematoxylin and eosin. The lesion intensity was classified as mild, moderate, or severe. The parasite load was determined using immunohistochemistry. The most important lesions consisted of multifocal to diffuse granulomas, megakaryocytic dysplasia, and medullary aplasia. There were no statistical differences between the three clinical groups regarding parasite load and lesion intensity. Asymptomatic dogs also presented high parasitism in the bone marrow as dogs with clinical signs of VL. It was concluded that, regardless of clinical group, the bone marrow is a site for multiplication ofLeishmania chagasi. Possibly, the bone marrow dysplasia may arise from the presence of many parasitized and activated macrophages in this organ. Consequently, it affects the profile of hematopoietic cells in the bone marrow and systemic circulation.


PLoS ONE ◽  
2015 ◽  
Vol 10 (10) ◽  
pp. e0141265 ◽  
Author(s):  
Fabrícia Alvisi de Oliveira ◽  
Aline Silva Barreto ◽  
Lays G. S. Bomfim ◽  
Talita Rebeca S. Leite ◽  
Priscila Lima dos Santos ◽  
...  

2016 ◽  
Vol 46 (11) ◽  
pp. 2029-2035 ◽  
Author(s):  
Vinícius Vasconcelos Gomes de Oliveira ◽  
Simone Regina Barros de Macedo ◽  
Flábio Ribeiro de Araújo ◽  
Carlos Alberto do Nascimento Ramos ◽  
Rafael Antonio Nascimento Ramos ◽  
...  

ABSTRACT: The aim of the present study was to investigate the correlations among chronic inflammatory reaction, immunostaining and parasite load in the genital system of female dogs naturally infected with Leishmania infantum . Animals (n = 10) used in this study were from the Department of Vector Control and Animal Surveillance of the municipality of Caruaru, state of Pernambuco, Brazil. Fragments of the vulva, vagina, cervix, uterine body, uterine horns and ovaries were submitted to histopathological analysis, immunohistochemistry (IHC) and DNA detection of amastigotes by qPCR. Correlations were found between the IHC findings and chronic inflammatory infiltrate related to L. Infantum only in the vulva and vagina; whereas, the same inflammatory reactions without immunostaining were observed in all organs, except the ovaries. L. Infantum DNA was detected in all organs of genital system, with no difference in parasite load observed among the different organs. No correlation was reported between parasite load and inflammatory lesions in the organs evaluated, except for the uterine body, in which an inverse correlation was detected. In conclusion, the vulva and vagina were the major sites of lesions and immunostaining for L. Infantum amastigotes in the genital system of female dogs. Moreover, parasite load exerted no influence on the intensity of the lesions in the organs evaluated.


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