Dirofilariasis involving the oral cavity: report of the first case from South America

Oral dirofilariasis is very rare with non-specific clinical manifestations. Here, we report the case of a 65-year-old South American woman with a submucosal nodule on her right buccal mucosa. The nodule was slightly tender and painful. Differential diagnoses included mesenchymal (lipoma or fibrolipoma, solitary fibrous tumor, and neurofibroma) or glandular benign tumors (pleomorphic adenoma) with secondary infections. We performed excisional biopsy. A histopathological examination revealed a dense fibrous capsule and a single female filarial worm showing double uterus appearance, neural plaque, well-developed musculature and intestinal apparatus. Dirofilariasis was diagnosed, and the patient was followed-up for 12 months without recurrence.

Dirofilariose humana em Joinville-SC: avaliação clinicopatológica dos primeiros casos relatados na região Sul / Human dirofilariasis in Joinville-SC: clinical-pathological assessment of the first cases reported in the Southern region

INTRODUÇÃO: Dirofilariose é uma zoonose rara causada pelo gênero Dirofilaria e acomete principalmente os pulmões, sendo capaz de simular neoplasia pulmonar. Pouca informação está disponível na literatura sobre a ocorrência e a distribuição de dirofilariose humana na América do Sul. Até 2004, haviam sido descritos apenas 50 casos de dirofilariose humana pulmonar no Brasil, sendo 37 apenas em São Paulo. OBJETIVO: Comprovar a existência de dirofilariose na região de Joinville-SC. MATERIAIS E MÉTODOS: Revisão de arquivos de laboratórios de anatomia patológica da cidade à procura de casos com os termos granuloma parasitário, helminto, helmintíase, verme, Dirofilaria e dirofilariose. Foram incluídos na pesquisa casos que satisfizeram os critérios para dirofilariose, segundo literatura específica. Os prontuários foram revisados e as amostras reprocessadas e analisadas histologicamente por seis colorações diferentes. RESULTADOS: Encontrou-se um caso em globo ocular e sete casos pulmonares, sendo o lobo inferior a localização preferencial (cinco casos). A análise microscópica revelou, nos casos pulmonares, nódulo bem delimitado, frequentemente centrado em uma artéria, com reação granulomatosa e necrose associada à fibrose e infiltrado inflamatório mono e polimorfonuclear, sendo possível identificar segmentos do parasita degenerado, compatível com Dirofilaria immitis. DISCUSSÃO: Todos os parasitas encontrados apresentam características morfológicas idênticas às relatadas na literatura para Dirofilaria immitis. A presença de D. immitis no globo ocular, como observada em um dos pacientes na presente revisão, é rara. CONCLUSÃO: A ocorrência de dirofilariose humana foi confirmada em Joinville e região, sendo causada pela Dirofilaria immitis.

INTRODUCTION: Dirofilariasis is a rare zoonosis caused by Dirofilaria genus, which affects mainly the lungs and may be misdiagnosed as lung cancer. Little information is available regarding the occurrence and distribution of human dirofilariasis in South America. Only 50 cases of human pulmonary dirofilariasis were described in Brazil until 2004, of which 37 were located in São Paulo. OBJECTIVE: To prove the existence of dirofilariasis in Joinville, SC. MATERIAL AND METHODS: The records of anatomic pathology laboratories of the city were reviewed in search for cases with the terms parasitic granuloma, helminth, helminthiasis, worm, Dirofilaria and dirofilariasis. According to specific literature, the cases that met the criteria for dirofilariasis were included in the study. The medical records were reviewed and the samples reprocessed and histologically analyzed by six different stains. RESULTS: We found one ocular case and seven pulmonary cases. The lower lobe was the main location (five cases). In all pulmonary cases, microscopic analysis revealed well defined nodules, frequently centered in a pulmonary artery, with granulomatous reaction and necrosis associated with fibrosis and mono and polymorphonuclear inflammatory infiltrate. It was also possible to identify segments of the deteriorated worm consistent with Dirofilaria immitis. DISCUSSION: All parasites found in this study show morphological characteristics similar to those reported in the literature on Dirofilaria immitis. The presence of D. immitis in the eye, as reported in one of the patients from this review, is rare. CONCLUSION: The occurrence of human dirofilariasis was confirmed in Joinville and region and it was caused by Dirofilaria immitis.

Histopathologic effects of dirofilaria immitis microfilaria on internal organs of dog confirming by PCR technique

The heartworm disease is an infectious disease of dogs with Dirofilaria immitis combined with cardiovascular and circulatory abnormalities. The heartworm disease can become a serious health risk when associated with a severe infection. In this study, a male, 8 year-old dog that died suddenly was necropsied and all tissues were examined grossly.Major organs including heart, lungs, liver, spleen, kidneys, brain, eyes, and testis were fixed in 10% neutral formalin, embedded in paraffin, sectioned at 5-micro m thickness, stained with hematoxylin and eosin, and examined with a light microscope. For each examined organ, paraffin-embedded tissues were cut and placed in eppendorf tubes for genomic DNA extraction. PCR was performed using two sets of primers for amplification of a 302 bp ITS-2 gene fragment and a 203 bp cytochrome oxidase subunit 1 [CO1] gene fragment of D. immitis. During the necropsy examination, 46 adult D. immitis were found in the portal vein, right ventricle, and atrium of the heart and pulmonary trunk. Microscopically, microfilarias were found throughout the vessels of different organs including lungs, kidneys, liver, heart, brain, and spleen. All tissues examined by PCR were positive for D. immitis ITS-2 and CO1. PCR technique now represents an effective method for identification of D. immitis from formalin-fixed samples

Periorbital mass with cellulitis caused by dirofilaria.

Dirofilariasis is a zoonotic disease caused by Dirofilaria, a parasite of domestic and wild animals. The disease is transmitted by inoculation of mosquitoes infected with the microfilariae during their blood meal. Accidental infection of man results in lung nodule, subcutaneous mass anywhere in the body or ocular lesion that may be subconjunctival or periorbital. The incidence of ocular dirofilariasis is on the rise in several parts of India particularly in Kerala. Here we report a case of ocular dirofilariasis with cellulitis presenting as a periorbital mass.

Ocular dirofilariasis, a case report

Accidental infection with animal filarial worms in humans is a dilemma for clinicians and parasitologists throughout the world. To date a variety of such rare parasitoses have been reported mostly in tropics and subtropics. Human dirofilariasis is among those unusual zoonotic infections that occasionally have been observed in the eye and in subcutaneous areas exhibiting with nodule for mation. Filarial worms are transmitted to humans through invertebrate biological vectors such as certain species of mosquitoes. The present report describes a peculiar case of ocular dirofilariasis in a 49-year-old man resident in Iran

Dirofilariosis en caninos: estudio anatomopatológico de 15 casos / Canine dirofilariosis: a pathologic anatomy study of 15 cases

El objetivo del presente estudio es reportar los cambios anatomopatológicos que ocurren en la dirofilariosis canina en su forma cardiopulmonar así como los daños relevantes que se producen en órganos vitales en la forma sistémica en caninos. La dirofilariosis canina también llamada enfermedad del gusano del corazón, es una enfermedad parasitaria producida por el nemátodo Dirofilaria inmitis que ocurre con una alta prevalencia a nivel mundial y constituye uno de los problemas patológicos más relevantes en el ámbito de la cría de caninos. La patogénesis de la enfermedad es bien conocida y sus cambios anatomopatológicos han sido bien documentados en otros países. En Venezuela se ha reportado la enfermedad con sus aspectos clínicos pero los cambios relevantes, tanto macroscópicos como la histopatología, no han recibido la atención que merecen. Quince caninos, 8 machos y 7 hembras de diferentes razas y entre 5 y 14 años de edad fueron necropsiados. Los cambios macro y microscópicos en órganos y tejidos de corazón, pulmón, bazo, hígado y riñon más relevantes son reportados. Se realizaron frotis sanguíneos detectándose la presencia de microfilarias con sus características típicas y se realizó la evaluación morfológica de parásitos adultos.

Dirofilariose pulmonar humana: relato de sete casos / Human pulmonary dirofilariasis: a report of seven cases

Dirofilariose pulmonar humana é uma doença rara causada pelo parasita Dirofilaria immitis. Apresenta-se usualmente como um nódulo pulmonar solitário que mimetiza câncer de pulmão. Embora considerada uma doença clinicamente benigna, uma biópsia pulmonar excisional é quase sempre necessária para o diagnóstico. Relatam-se as características epidemiológicas, clínicas e radiológicas de sete casos de dirofilariose pulmonar humana em Florianópolis. De sete pacientes relatados, seis tiveram como achado radiológico um nódulo pulmonar e foram submetidos à biópsia pulmonar excisional para o diagnóstico. Em um paciente, a imagem radiológica não estava disponível para revisão e, portanto, não foi descrita no trabalho; o diagnóstico foi estabelecido pela biópsia transbrônquica

The first Korean case of human pulmonary dirofilariasis

Human pulmonary dirofilariasis has been documented from many parts of the world, but not in Korea so far. We experienced a patient of pulmonary dirofilariasis who had visited a local clinic because of chest pain for 1 month. On chest radiograph, a coin lesion of 2 cm diameter and enlargement of the mediastinal lymph node were shown. An exploratory lung resection was done. Pathologically the lesion was a pulmonary dirofilariasis complicated with necrotic pneumonia, fibrosis, and infarction. At the center of the lesion, degenerated nematode sections with multilayered cuticle, thick musculature, and bilateral internal ridges on each side were found, which was identified to be Dirofilaria immitis. This is the first report of human pulmonary dirofilariasis in Korea.

Histopathological diagnosis of subcutaneous Dirofilaria repens infection in humans.

The host tissue response in humans, based on a study of biopsies of 14 subcutaneous nodules caused by Dirofilaria repens is described. The response was characterized by accumulation of eosinophilic material or eosinophilic pus adjacent to the parasite with surrounding granulomatous inflammation associated with extensive eosinophil infiltration of the surrounding tissue. Unlike with fungal lesions, fat necrosis was conspicuously absent. Nodules were all less than 3 cm in size. Fifteen percent of the smaller nodules (less than 1 cm) and 30% of the larger nodules required extensive examination of tissue to visualize the parasite. It is concluded that when typical tissue reactions are seen, extended histological processing is indicated for accurate diagnosis of dirofilariasis, by demonstrating the parasite.

Human pulmonary dirofilariasis: a review

Os autores realizaram minuciosa revisao sobre a distribuicao geografica, a clinica, a patologia e o diagnostico da dirofilariase pulmonar humana. Esta zoonose, que tem como principal agente etiologico a Dirofilaria immitis, e um problema medico porque produz um quadro clinico, embora benigno, que se confunde com neoplasia e, assim interpretado, pode conduzir o paciente a cirurgia do torax. Dos 229 casos citados na literatura, apenas 17 foram descritos no Brasil, apesar da existencia de condicoes muito favoraveis a transmissao da infeccao para o homem, admitindo-se portanto, que e uma parasitose subdiagnosticada. Finalmente, a importancia do diagnostico diferencial entre dirofilariase e neoplasias pulmonares nos casos de presenca de nodulo solitario subpleural ("coin lesion") e destacada, alem do que o desenvolvimento e aprimoramento de tecnicas modernas de diagnostico imunologico sao essenciais para distinguir esta doenca benigna de outras patologias mais serias e evitar cirurgias desnecessarias. Essas tecnicas poderao fornecer a prevalencia real da parasitose em nosso meio.

Pulmonary dirofilariasis: first reported case in Puerto Rico

The first case of human pulmonary dirofilariasis in our country is reported. The etiopathogenesis and pathological findings of the zoonosis are discussed