Recurrence of aplastic anemia following cyclophosphamide and syngeneic bone marrow transplantation: evidence for two mechanisms of graft failure

Two patients with aplastic anemia were treated with high-dose cyclophosphamide and marrow transplantation from their normal, genetically identical twin. Both patients rapidly recovered normal marrow function, but marrow failure recurred 13 and 18 months later. Because donor and host pairs were identical twins, these cases of graft failure could not have resulted from the usual cause of graft failure, ie, immunological reactivity of host cells against unshared minor histocompatibility antigens of the donor. These results imply that there are at least two mechanisms responsible for graft failure after marrow transplantation for severe aplastic anemia.     

Tetralogy of Fallot: MR findings

Surgical treatment of patients with tetralogy of Fallot requires accurate definition of all anatomic structures, particularly the central pulmonary arteries. Magnetic resonance (MR) images of 22 patients with tetralogy of Fallot were studied to assess their usefulness in providing information regarding the spectrum of anatomic abnormalities in this condition. MR findings were compared with information obtained at catheterization (in 16 patients) and at surgery (in nine patients), both of which were performed within 3 months of MR imaging. Ventricular chamber enlargement and wall hypertrophy were clearly delineated in most of the 17 patients who were examined before definitive surgical repair, and ventricular septal defects were visualized in all 17. Palliative systemic-to-pulmonary shunts were visualized in 11 patients and could be evaluated for patency. Most important, the morphology and size of the right ventricular outflow tract and central pulmonary arteries could be accurately assessed. Pulmonary artery measurements obtained from MR images demonstrated excellent correlation with angiographic measurements. In six patients examined after complete surgical repair, MR images accurately reflected changes in pulmonary artery outflow tract morphology and complications, such as residual pulmonary artery stenosis and thrombosis. The findings suggest that MR imaging can complement or obviate catheterization in the evaluation of tetralogy of Fallot with regard to suitability for definitive surgical repair.     

Craniosynostosis in X-linked hypophosphataemic rickets

A report of three cases of craniosynostosis in X-linked hypophosphataemic rickets (XLH) is presented. The literature is reviewed, suggesting that craniosynostosis is relatively common in XLH and that boys may be more at risk than girls. It is recommended that radiological screening be offered to all patients with XLH.     

The thoracic aorta studied by MR imaging

Thirty-three patients with a variety of disorders of the thoracic aorta (aneurysm, dissection, Marfan syndrome, coarctation/pseudocoarctation, L-transposition, and Takayasu disease) were evaluated with magnetic resonance (MR) imaging. MR imaging delineated the presence and extent of thoracic aortic aneurysms and showed the relationship of the aneurysm to arch vessels; it also demonstrated intimal flaps and individual lumina in types A and B aortic dissection. Dilation of the ascending aorta in Marfan syndrome and focal narrowing of the aorta in coarctation were well visualized. The anteroposterior and side-to-side relationships of the aorta and pulmonary artery in L-transposition were demonstrated, as were aortic wall thickening and branch vessel narrowing in Takayasu arteritis. Initial experience suggests that MR imaging may provide a noninvasive method for evaluating thoracic aortic disease. Limitations include inferior spatial resolution, occasional difficulty in imaging the entire region of interest in one section, lack of signal from calcifications, and inability to monitor critically ill patients.     

Usefulness of DNA ploidy measurement on liquid-based smears showing conflicting results between cytology and high-risk human papillomavirus typing

To improve the positive predictive value (PPV) for high-risk human papillomavirus (HR-HPV) in primary screening, DNA ploidy was measured on the same liquid-based sample by image cytometry in 984 cases showing discrepancies between cytology and HR-HPV testing. Of the conflicting results, 14.5% corresponded to a cytologic lesion (from atypical squamous cells of undetermined significance to high-grade squamous intraepithelial lesion [HSIL]) without HPV detected, and 85.5% of smears were within normal limits but revealed an HR-HPV infection. A suspect DNA profile was associated significantly with a lesion. In 497 patients who underwent repeated HPV testing, a normal DNA profile at the first smear predicted the clearance of HPV infection (sensitivity, 81.5%; specificity, 45.4%; PPV, 69%; negative predictive value, 62.4%). In persistent HR-HPV infection, a suspect DNA profile at the first smear increased the PPVfrom 10.8% to 22.7% for the detection of a histologically proven HSIL with a sensitivity of 95.2%. DNA ploidy can be used to select smears with high risk of HSIL, especially in cases of persistent HR-HPV infection.     

Cell cycle and/or proliferation markers: what is the best method to discriminate cervical high-grade lesions?

The aim of this study on a series of biopsies diagnosed as normal, metaplastic, low-grade squamous intraepithelial lesions (LSILs), and high-grade squamous intraepithelial lesions (HSILs) was dual: to determine the chronology of cell cycle and proliferation abnormalities after human papillomavirus infection during the development of squamous intraepithelial lesions and to determine the best diagnostic indicator(s) linked to the appearance of an HSIL. Ninety-nine cervical biopsies, 18 normal, 9 with metaplastic changes, 29 LSIL, and 43 HSIL (23 cervical intraepithelial neoplasia 2 and 20 cervical intraepithelial neoplasia 3), were analyzed by image cytometry for DNA ploidy and p16INK4A determination, AgNOR counting, MIB-1, and ICBP90 immunostaining quantification. The human papillomavirus status had been previously determined on corresponding cytological smears with the Hybrid Capture II test. Suspect DNA profile and p16INK4A staining were the first significant events that preceded the increase of cell proliferation. Indeed, these markers were the best tests for the detection of a lesion, whatever its grade (positive predictive values of 90% and 100%, respectively). The presence of MIB-1- or ICBP90-positive cells in the upper two thirds of the epithelium was a very accurate feature to select HSIL (sensitivity, 100% for MIB-1) but with a low specificity. The sensitivity of a suspect DNA profile associated with a positive MIB-1 or ICPB90 immunostaining for the detection of an HSIL was, respectively, 92.8% and 92.7%; their specificities were 54.2% and 44%; their positive predictive values were 78% and 73%; their negative predictive values were 81.2% and 78.6%; and the global values were 78.8% and 74.3%. Thus, the most accurate test to distinguish an LSIL from an HSIL was the association of a suspect DNA profile and the presence of MIB-1- or ICBP90-positive cells in the upper two thirds of the epithelium.     

Transverse cerebellar diameter on cranial ultrasound scan in preterm neonates in an Australian population

OBJECTIVE: Fetal measurement of transverse cerebellar diameter (TCD) has been shown to correlate well with gestational age (GA), even in the presence of growth retardation. The aim of this study was to define the normal range of TCD in preterm neonates in an Australian population between 23 and 32 weeks GA. METHODOLOGY: Infants admitted to the Royal Women's Hospital, Melbourne, having routine cranial ultrasound scans (< 1500 g and/or of gestational age 相似文献