A case of hypersensitivity pneumonitis with giant cells in a female dental technician.

OBJECTIVES: Dental technicians are exposed to methyl methacrylate(MMA) and hard metal dusts while working, and several cases of hypersensitivity pneumonitis caused by the exposure have been reported. The authors experienced a case of hypersensitivity pneumonitis in a female dental technician who had 10 years' work experience and report the case with clinical evidence. METHOD: The patient's work, personal, social, and past and present medical histories were investigated based on patient questioning and medical records. Furthermore, the workplace conditions and tools and materials the patient worked with were also evaluated. Next, the pathophysiology and risk factors of pneumonitis were studied, and studies on the relationship between hypersensitivity pneumonitis and a dental technician's exposure to dust were reviewed. Any changes in the clinical course of her disease were noted for evaluation of the work-relatedness of the disease. RESULTS: The patient complained of cough and sputum for 1 year. In addition, while walking up the stairs, the patient was not able to ascend without resting due to dyspnea. She visited our emergency department due to epistaxis, and secondary hypertension was incidentally suspected. Laboratory tests including serologic, electrolyte, and endocrinologic tests and a simple chest radiograph showed no specific findings, but chest computed tomography revealed a centrilobular ground-glass pattern in both lung fields. A transbronchial biopsy was performed, and bronchoalveolar washing fluid was obtained. Among the findings of the laboratory tests, microcalcification, noncaseating granuloma containing foreign body-type giant cells, and metal particles within macrophages were identified histologically. Based on these results, hypersensitivity pneumonitis was diagnosed. The patient stopped working due to admission, and she completely quit her job within 2 months of restarting work due to reappearance of the symptoms. CONCLUSION: In this study, the patient did not have typical radiologic findings, but pathological evaluation of the lung biopsy from the bronchoscope led to the suspicion of pneumonitis. Under the microscope, the sample contained fibrotic changes in the lung, multinucleated giant cells, and particles in macrophages and was diagnosed as dental technician pneumoconiosis by the pathology. Working as a dental technician had directly exposed her to light metal dust and MMA, and her clinical symptoms and radiologic findings subsided after withdrawal from exposure to the workplace. These outcomes led to the diagnosis of hypersensitity pneumonitis due to MMA exposure and strong work-relatedness.

CT, MR, and angiography findings of a solitary fibrous tumor of the larynx: a case report.

This report details the CT, MR, and angiography findings of a solitary fibrous tumor involving the larynx of a 34-year-old man. A precontrast CT scan revealed a well-defined isodense mass in the submucosal region of the supraglottic larynx. The tumor appeared as a mixed intensity lesion on the T1- and T2-weighted MR images. A T2-weighted MR image showed a central, round, and low signal intensity area within the mass. For both the CT and MR images, the mass demonstrated heterogeneous enhancement following the administration of contrast material. The angiography showed a hypervascular tumor with heterogeneous persistent staining.

The prevalence and significance of incidental thyroid nodules identified on computed tomography.

PURPOSE: The purpose of this study was to assess the prevalence of incidental thyroid nodules (ITN) found on computed tomography (CT) of the neck and to determine whether CT characteristics could distinguish malignant from benign thyroid lesions. MATERIALS AND METHODS: We retrospectively reviewed CT scans in 734 patients without known thyroid disease (384 men and 350 women; mean age, 49.8 +/- 13.7 years). The CT findings of ITN such as size, shape (anteroposterior-transverse diameter ratio [AP/T ratio]), margin, peripheral enhancing rim, intralesional calcification, and attenuation characteristics were analyzed and correlated with ultrasonographic (US) findings. RESULTS: One hundred sixty ITNs were noted in 123 (16.8%) patients. Of 120 ITNs whose histological diagnoses were available, 15 (12.5%) were malignant. Malignant nodules more frequently showed nodular or rim calcifications (46.7% vs 13.3%; P < 0.0005), AP/T ratio of greater than 1.0 (33.3% vs 9.5%; P < 0.05), and mean attenuation value on contrast-enhanced scan of greater than 130 Hounsfield units (86.7% vs 49.5%; P < 0.05) than benign nodules. CONCLUSIONS: We found at least a 9.4% (15/160) prevalence of malignancy among ITN detected on CT. The further evaluation with US or biopsy should be performed, if an ITN shows CT features suggesting malignancy (calcification; AP/T ratio, >1.0; or mean attenuation value, >130 HU).