Case Of Human Pulmonary Dirofilariasis Research Articles

A rare case of human pulmonary dirofilariasis with nodules mimicking malignancy: approach to diagnosis and treatment

BackgroundHuman pulmonary dirofilariasis is a rare zoonosis caused by the dog worm Dirofilaria spp., a parasite transmitted by mosquitos and resulting in peripheral lung nodules. The filarial nematode enters the subcutaneous tissue, travels to the right ventricle and dies causing a small pulmonary infarction that may embolize through the pulmonary vessels and may appear as a solitary nodule. These nodules are usually incidentally identified in asymptomatic patients undergoing chest imaging studies, and are generally interpreted to be malignant.Case presentationWe present the case report of a human dirofilariasis in a patient with multiple pulmonary nodules resected using video-assisted thoracic surgery (VATS). According to our literature review, this is the first case with double synchronous lung nodules reported in Italy.ConclusionsMinimally invasive resection with histologic examination may be the best approach for the diagnosis and treatment of pulmonary dirofilariasis. Polymerase Chain Reaction testing may provide a more accurate etiological diagnosis in case of an inconclusive pathology result.

A Case of Human Pulmonary Dirofilariasis in a 48-Year-Old Korean Man

Dirofilariasis is a rare disease in humans. We report here a case of a 48-year-old male who was diagnosed with pulmonary dirofilariasis in Korea. On chest radiographs, a coin lesion of 1 cm in diameter was shown. Although it looked like a benign inflammatory nodule, malignancy could not be excluded. So, the nodule was resected by video-assisted thoracic surgery. Pathologically, chronic granulomatous inflammation composed of coagulation necrosis with rim of fibrous tissues and granulations was seen. In the center of the necrotic nodules, a degenerating parasitic organism was found. The parasite had prominent internal cuticular ridges and thick cuticle, a well-developed muscle layer, an intestinal tube, and uterine tubules. The parasite was diagnosed as an immature female worm of Dirofilaria immitis. This is the second reported case of human pulmonary dirofilariasis in Korea.

Dirofilariose humana em Joinville-SC: avaliação clinicopatológica dos primeiros casos relatados na região Sul

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 Sao 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.

Detection of Dirofilaria (Nochtiella) repens DNA by polymerase chain reaction in embedded paraffin tissues from two human pulmonary locations

We here report two new cases of human pulmonary dirofilariasis in men aged 62 and 64 from Northern and Central Italy, respectively. Both were asymptomatic and the infections were discovered incidentally when chest radiographs taken for another reason revealed the presence of a coin lesion. The initial clinical diagnosis was oriented towards a lung tumour, and an excisional lung biopsy after thoracotomy was necessary for the final diagnosis. Pathologically, the lesion consisted of a roundish subpleural infarct with a central thrombotic artery containing sections of an immature nematode: Dirofilaria repens was diagnosed histologically in one case, the necrotic condition of the worm allowing only genus identification, Dirofilaria, in the other case. In both samples, PCR analysis amplified a 246 bp product, specific for the IpS insert 11 of D. repens. The authors stress the role of PCR in the diagnosis of this parasite from paraffin samples, also in cases in which identification of the species was not possible by conventional morphology due to poor conservation of the worm. These cases represent the first PCR-based diagnosis of D. repens in a human pulmonary dirofilariasis on samples embedded in paraffin.

Pulmonary Dirofilariasis Mimicking Lung Tumor with Chest Wall and Mediastinal Invasion

We present a case of human pulmonary dirofilariasis, diagnosed in a 55-year-old heavy smoker (male) by wedge resection of the pulmonary lesion and histologic examination. The dirofilaria lesion had the clinical and radiographic appearance of a peripheral pulmonary lesion invading the anterior chest wall and mediastinum. The reported radiographic image of the disease is different from the usually described picture of a pulmonary coin lesion.

Human Pulmonary Dirofilariasis: Analysis of 24 Cases From Sao Paulo, Brazil

To present the clinical, radiologic, and pathologic aspects of 24 cases of human pulmonary dirofilariasis (HPD) from São Paulo, Brazil. Retrospective study of 24 patients with a confirmed diagnosis of HPD over a 14-year period (from February 1982 to June 1996). Thoracic Surgery and Pulmonary Division, University of São Paulo and Hospital Albert Einstein, São Paulo, Brazil. Seventeen patients were male (70.1%) and seven were female (29.9%). Their mean age was 51.4 years. Fifty-four percent of the patients were asymptomatic and 75% had a well-circumscribed noncalcified peripheral subpleural pulmonary nodule on the chest radiograph and thoracic CT scan, located preferentially in the lower lobes. The diagnosis was made after thoracotomy and wedge resections in 16 patients, by videothoracoscopy in six, after a pleural biopsy in one, and after necropsy in one. The pathologic examination of all the nodules revealed a central zone of necrosis, surrounded by a narrow granulomatous zone and peripherally by fibrous tissue. Pulmonary vessels exhibit varying degrees of endarteritis. In all cases, a dead worm, usually necrotic and fragmented, was found. A subpleural, noncalcified pulmonary nodule in the appropriate clinical and epidemiologic setting should alert the clinician, radiologist, or pathologist to the possibility of Dirofilaria. HPD should be considered in the differential diagnosis of pulmonary nodules.

Pulmonary coin lesions caused by Dirofilaria immitis

The dog heartworm Dirofilaria immitis has been diagnosed by thoracotomy as the etiology of neoplastic-appearing nodules in two patients in the Peoria, Illinois area. This brings the total number of reported cases of human pulmonary dirofilariasis to approximately 81 in the United States. The major concern of this benign disease is that in making the diagnosis the patients undergo the risk of surgery because of the presumed preoperative diagnosis of cancer. Greater awareness of this disease is needed as the geographic distribution of human pulmonary dirofilariasis expands in this country.

A SURGICAL CASE OF PULMONARY DIROFILARIASIS

We experienced one case of human pulmonary dirofilariasis, which had been characterized recently as one of Zoonoses. A 70-year-old female, who had been suffering from hypertension for a long time, had a coin lesion in the periphery of the left upper lung field on the chest roentgenogram. Partial resection of the lung was, therefore, performed under the tentative diagnosis of lung cancer. Diagnosis of this disease was established by histopathological findings and serological examinations (Agar-gel diffusional absorptional assay, enzyme-linked immunosorbent assay and mixed passive hemagglutination assay). This disease is extremely rare. But it is clinically important, because of difficulties to differentiate from lung cancer and other respiratory diseases, and to diagnose preoperatively. We discussed the literatures of this disease in Japan, especially about clinical features.

Human pulmonary dirofilariasis: Does diagnosis require thoracotomy?

The incidence of pulmonary coin lesions as a result of Dirofilaria immitis (dog heartworm) seems to be increasing. A case of human pulmonary dirofilariasis is described, and its pathogenesis and the limitations of preoperative diagnostic tests in this condition are discussed.

Human Pulmonary Dirofilariasis Presenting as a Solitary Pulmonary Nodule

A case of human pulmonary dirofilariasis had positive serologic testing postoperatively. Increased awareness of this entity as a cause of solitary pulmonary nodules may lead to preoperative serologic and intradermal testing, and to the possibility of arriving at a preoperative diagnosis.

Pulmonary Dirofilariasis

The two cases of human pulmonary dirofilariasis reported bring the number of cases published in the English literature to 21. As in most cases of pulmonary dirofilariasis, these two patients presented roentgenologically single noncalcified coin lesions and required thoracotomy for diagnosis. Pathologically, the lesions were rounded ischemic infarcts associated with pulmonary arterial thrombosis due to a nematode identified as Dirofilaria. The worm is morphologically indistinguishable from D immitis, the common canine heartworm. The life cycle of the parasite and the two clinical forms of human dirofilariasis are briefly discussed. The two cases of human pulmonary dirofilariasis reported bring the number of cases published in the English literature to 21. As in most cases of pulmonary dirofilariasis, these two patients presented roentgenologically single noncalcified coin lesions and required thoracotomy for diagnosis. Pathologically, the lesions were rounded ischemic infarcts associated with pulmonary arterial thrombosis due to a nematode identified as Dirofilaria. The worm is morphologically indistinguishable from D immitis, the common canine heartworm. The life cycle of the parasite and the two clinical forms of human dirofilariasis are briefly discussed.

Human Pulmonary Dirofilariasis Manifesting as a "Coin" Lesion

DIROFILARIA or heartworm is a common parasite of dogs, cats, and other mammals. It is rarely encountered in human beings. Recently, two cases of human pulmonary dirofilariasis were reported by Harrison and Thompson.1In their review of the literature they found only three cases up to 1965. Extrapulmonary human dirofilariasis is the more common form of human infestation by this parasite. Faust2in 1957 reviewed the literature and collected 37 cases, most of them were found in southern Europe. Four of the cases of human pulmonary dirofilariasis mentioned above presented as a coin lesion in a roentgenogram of the chest. The fifth case presented as a pulmonary infarct with pneumonitis. Because of this clinical pattern, human pulmonary dirofilariasis should be considered in the differential diagnosis of coin lesion of the lung. The following case is being reported to add to the small list of cases of human pulmonary