Cerebrotendinous xanthomatosis is a rare genetic disorder characterized by a decrease in activity of the hepatic sterol 27-hydroxylase involved in the cholesterol metabolism and excretion. Consequently, lipid (cholesterol/cholestanol) deposition is observed in different regions of the body, especially tendons, central nervous system and eye lens. The present report describes the cases of two sisters affected by this disease, highlighting the main imaging findings.

Keywords: Cerebrotendinous xanthomatosis, Xanthomatosis, Hypercholesterolemia, Magnetic resonance imaging, Computed tomography

Hypersensitivity pneumonitis is a diffuse interstitial and granulomatous lung disease caused by the inhalation of any one of a number of antigens. The objective of this study was to illustrate the spectrum of abnormalities in high-resolution computed tomography and histopathological findings related to hypersensitivity pneumonitis. We retrospectively evaluated patients who had been diagnosed with hypersensitivity pneumonitis (on the basis of clinical-radiological or clinical-radiological-pathological correlations) and had undergone lung biopsy. Hypersensitivity pneumonitis is clinically divided into acute, subacute, and chronic forms; high-resolution computed tomography findings correlate with the time of exposure; and the two occasionally overlap. In the subacute form, centrilobular micronodules, ground-glass opacities, and air trapping are characteristic high-resolution computed tomography findings, whereas histopathology shows lymphocytic inflammatory infiltrates, bronchiolitis, variable degrees of organizing pneumonia, and giant cells. In the chronic form, high-resolution computed tomography shows traction bronchiectasis, honeycombing, and lung fibrosis, the last also being seen in the biopsy sample. A definitive diagnosis of hypersensitivity pneumonitis can be made only through a multidisciplinary approach, by correlating clinical findings, exposure history, high-resolution computed tomography findings, and lung biopsy findings.

Keywords: Alveolitis, extrinsic allergic/pathology; Tomography, X-ray computed; Lung diseases, interstitial.