RESUMEN
Canine heartworm disease caused by Dirofilaria immitis is an important disease of dogs. The aim of this retrospective study was to estimate the prevalence of canine heartworm disease and evaluate cases of caval syndrome in dogs submitted for necropsy in Grenada. Out of 1617 dogs necropsied over a period of 13 years (2001-2013), 249 were found to be infected with D. immitis; giving an overall prevalence of 15.4% (95% confidence interval, 13.6% to 17.1%). There was no significant difference between male and female dogs with respect to canine heartworm infection (p = 0.3). During this period, the annual prevalence of canine heartworm disease was 22% in 2001 before slightly declining to an average of 18% in 2002-2003 and peaking at 26.8% in 2004-2005. From 2006 onwards, annual prevalence rates have steadily been decreasing; reaching the lowest (9%) in 2013. Among the 249 positive cases, 33 (13.2%) of the dogs had caval syndrome. Caval syndrome cases presented with concurrent clinical signs and were associated with cardio-pulmonary and hepatic gross lesions at necropsy. Aberrant migration of D. immitis was also noted in 2 dogs with caval syndrome. This is the first report which presents the findings of canine heartworm disease with caval syndrome in Grenada.
Asunto(s)
Dirofilaria immitis/aislamiento & purificación , Dirofilariasis/epidemiología , Enfermedades de los Perros/epidemiología , Animales , Dirofilariasis/parasitología , Enfermedades de los Perros/parasitología , Perros , Femenino , Grenada/epidemiología , Atrios Cardíacos/parasitología , Atrios Cardíacos/patología , Insuficiencia Cardíaca/parasitología , Insuficiencia Cardíaca/veterinaria , Masculino , Prevalencia , Estudios Retrospectivos , Factores Sexuales , Vena Cava Inferior/parasitología , Vena Cava Inferior/patologíaRESUMEN
Através da análise morfológica e morfométrica de cortes foi estudada a ocorrência de ninhos de T. cruzi na veia central e no parênquima das supra-renais, no miocárdico ventricular esquerdo e na veia cava inferior de chagásicos crônicos. Em 36 casos estudados 50 por cento apresentavam fleboparasitismo supra-renálico (total 29 ninhos); 3,1 por cento apresentavam parasitismo na veia cava (apenas 1 ninho) e em 16,8 por cento dos casos encontramos miocardiócitos parasitados (total 23 ninhos). A densidade de parasitismo, expressa em número de ninhos por 100mm² de tecido examinados, foi de 0,585 para a veia supra-renálica, de 0,001 para a veia cava e 0,01 para o miocárdio . Em 269.103,1mm² de parênquima supra-renálico näo encontrando nenhum ninho. Embora tenha sido a menor área examinada, a veia central apresentou a maior freqüência de ninhos de T. cruzi. Como a diferença básica entre estes tecidos está na riqueza de corticóides no sangue que nutre a veia central, podemos admitir que esta prevalência talves seja devido ao ambiente hormonal, que por seu efeito imunossupressor e anti-inflamatório favoreceria a sobrevida dos parasitas
Asunto(s)
Adulto , Persona de Mediana Edad , Humanos , Masculino , Femenino , Glándulas Suprarrenales/irrigación sanguínea , Glándulas Suprarrenales/parasitología , Enfermedad de Chagas/parasitología , Enfermedad Crónica , Corazón/parasitología , Venas/parasitología , Vena Cava Inferior/parasitologíaRESUMEN
By morphological and morphometric analyses of serial sections the occurrence of T. cruzi nests in the central vein and in the parenchyma of adrenal glands, in the left ventricular wall and in the inferior vena cava wall in chronic Chagasic patients was studied. Of 36 cases 50% showed parasites in the adrenal central vein wall (total 29 nests), 3.1% showed parasites in the vena caval wall (only I nest) and 16.8% we found parasites in the myocardiocytes (total 23 nests). The density of parasites measured in the nests for each 100mm2 of the tissue examined, was 0.585 for the adrenal vein, 0.001 for the vena cava and 0.01 for the myocardium. No nest was found in 269103.1mm2 of adrenal parenchyma. Although the central vein area examined was smaller, it showed the largest frequency of T. cruzi nests. Since a basic difference between these tissues is the great quantity of corticoids in the blood of the adrenal central vein, this prevalence may be because of this hormonal ambient, which with its immunosuppressor and anti-inflammatory effects could help T. cruzi survival.
Asunto(s)
Glándulas Suprarrenales/irrigación sanguínea , Glándulas Suprarrenales/parasitología , Enfermedad de Chagas/parasitología , Adulto , Anciano , Enfermedad Crónica , Femenino , Corazón/parasitología , Humanos , Masculino , Persona de Mediana Edad , Venas/parasitología , Vena Cava Inferior/parasitologíaRESUMEN
The occurrence of nest of trypanosoma cruzi in the smooth muscle cells of the central veins of the adrenal glands and the inferior vena cava was studied in 21 chronic Chagas' patients, by serial sections. Nine patients presented parasites in the adrenal veins, with a total of 24 nests, and only one nest was found in the inferior vena cava. The area of muscular tissue examined was of 2944.3 mm2 for the adrenal veins and of 47808.6 mm2 for the vena cava, giving a relation of 0.815 nests/100 mm2 for the adrenal vein and of 0.002 for the vena cava. Thus the smooth muscle of the adrenal vein was 407 times more parasited than the muscular wall of the inferior vena cava. This higher parasitism of the adrenal vein by trypanosoma cruzi in chronic Chagas' disease may be determined by its greater corticosteroid concentration, which can reduce the anti-trypanosomal defenses.
Asunto(s)
Glándulas Suprarrenales/irrigación sanguínea , Cardiomiopatía Chagásica/patología , Trypanosoma cruzi/aislamiento & purificación , Vena Cava Inferior/parasitología , Glándulas Suprarrenales/patología , Animales , Humanos , Venas/parasitología , Vena Cava Inferior/patologíaRESUMEN
Estudou-se comparativamente a ocorrência de ninhos do Tripanosoma cruzi na musculatura lisa de veia central das suprarenais e da cava inferior em 21 chagásicos crônicos, através do exame de cortes seriados, nos quais foram tomadas as medidas da área de tecido muscular examinada. Dos 21 chagásicos crônicos estudados, 9 (42,8%) apresentavam fleboparasitismo supra-renálico com um total de 24 ninhos e em apenas um deles (4,8%) foi encontrado um ninho de T. cruzi na cava inferior. A área de tecido muscular examinada foi de 2.944,3 mm**2 para a veia cava, o que nos fornece uma densidade de parasitismo de 0,815 ninhos por 100 mm[[2 na veia supra-renálica foi 407 vezes mais parasitada que a musculatura da cava. Esta predileçäo do T. cruzi para a veia central da supra-renal parece relacionada à sua riqueza em hormônios corticóides que podem determinar inibiçäo das defesas anti-tripanosoma