Spectrum of Epstein-Barr virus infection in Japanese children: a pictorial essay

Shedding light on inflammatory pseudotumor in children: spotlight on inflammatory myofibroblastic tumor

Inflammatory pseudotumor is a generic term used to designate a heterogeneous group of inflammatory mass-forming lesions histologically characterized by myofibroblastic proliferation with chronic inflammatory infiltrate. Inflammatory pseudotumor is multifactorial in etiology and generally benign, but it is often mistaken for malignancy given its aggressive appearance. It can occur throughout the body and is seen in all age groups. Inflammatory pseudotumor has been described in the literature by many organ-specific names, resulting in confusion. Recently within this generic category of inflammatory pseudotumor, inflammatory myofibroblastic tumor has emerged as a distinct entity and is now recognized as a fibroblastic/myofibroblastic neoplasm with intermediate biological potential and occurring mostly in children. We present interesting pediatric cases of inflammatory myofibroblastic tumors given this entity's tendency to occur in children. Familiarity and knowledge of the imaging features of inflammatory pseudotumor can help in making an accurate diagnosis, thereby avoiding unnecessary radical surgery.

Hemophagocytic lymphohistiocytosis in children: abdominal US findings within 1 week of presentation

PURPOSE

To evaluate the ultrasonographic (US) findings at presentation in a series of children who received a diagnosis of hemophagocytic lymphohistiocytosis (HLH) at a single institution.

MATERIALS AND METHODS

All available results of imaging studies of children who received a diagnosis of HLH between January 1985 and June 2000 were retrieved. For nine patients, abdominal US images obtained within 1 week of presentation to the hospital were reviewed retrospectively by two radiologists who were aware of the diagnosis and of the original interpretation of each study. US images were examined for evidence of splenomegaly, hepatomegaly, ascites, gallbladder wall thickening, increased periportal echogenicity, lymphadenopathy, pleural effusion, and nephromegaly. Any other abnormalities were also recorded. Differences in interpretation were resolved by consensus. The patients ranged in age from 2 months to 4(1/2) years. The male-to-female ratio was 5:4.

RESULTS

Findings at presentation included splenomegaly (in eight of the nine children), hepatomegaly (in seven children), ascites (in six children), gallbladder wall thickening (in six children), increased periportal echogenicity (in three children), lymphadenopathy (in three children), and pleural effusion (in two children). Miscellaneous findings in individual patients included coarse hepatic echotexture with a single 9-mm hypoechoic focus in the liver, multiple hypoechoic foci in the spleen, nephromegaly, gallstone, increased renal cortical echogenicity, and mural thickening of the duodenum.

CONCLUSION

In the appropriate clinical setting, the differential diagnosis of a combination of hepatosplenomegaly, ascites, gallbladder wall thickening, increased periportal echogenicity, lymphadenopathy, and/or pleural effusion should include HLH.