Diferential diagnosis between esophageal granuloma and pulmonary metastasis

ABSTRACT

Background: Spirocercosis is a parasitic infection caused by Spirocerca lupi. This pathology affects canid carnivores, especially domestic dogs. Early diagnosis has been proven challenging and most infected animals are diagnosed when disease is in advanced stage. Exams such as computed tomography scans or radiographs can aid in disease confirmation. Radiographic exam frequently reveals the presence of a mass located in mediastinal region, which can be erroneously diagnosed as pulmonary mass. The aim of this study was to report the differential diagnosis between paraesophageal granuloma, possibly due to spirocercosis, and pulmonary metastasis in a dog with a history of neurofibrosarcoma.Case A 8 year-old male Cocker Spaniel dog, weighing 17.4 kg, was presented with anterior limb suspension and a recurrent nodule of 2.0 cm diameter, located on the main pad, with previous diagnosis of neurofibrosarcoma (malignant Schwannoma). Routine evaluation work-up included thoracic radiographs and abdominal ultrasound for clinical staging, electrocardiogram, complete blood count (CBC), coagulogram, renal and hepatic function tests, with results within the normal range for the species. The dog submitted to left anterior limb amputation due to recurrent neurofibrosarcoma in the carpal region. Histopathological exam confirmed recurrent neurofibrosarcoma without vascular invasion. Considering neoplasm biological behavior and clean surgical margins, only routine follow-up was established, with clinical exams. The dogwas presented to the Veterinary Hospital five months after surgical treatment and it was presented with fever, prostration, and history of vomiting. Radiographic exam showed a circumscribed mass in caudal mediastinal area. Computed tomography scan was performed to best evaluate the mass and the result was compatible with paraesophageal abscess.[...]