Clinical cone beam computed tomography compared to high-resolution peripheral computed tomography in the assessment of distal radius bone.

UNLABELLED: Clinical cone beam computed tomography (CBCT) was compared to high-resolution peripheral quantitative computed tomography (HR-pQCT) for the assessment of ex vivo radii. Strong correlations were found for geometry, volumetric density, and trabecular structure. Using CBCT, bone architecture assessment was feasible but compared to HR-pQCT, trabecular parameters were overestimated whereas cortical ones were underestimated. INTRODUCTION: HR-pQCT is the most widely used technique to assess bone microarchitecture in vivo. Yet, this technology has been only applicable at peripheral sites, in only few research centers. Clinical CBCT is more widely available but quantitative assessment of the bone structure is usually not performed. We aimed to compare the assessment of bone structure with CBCT (NewTom 5G, QR, Verona, Italy) and HR-pQCT (XtremeCT, Scanco Medical AG, Brüttisellen, Switzerland). METHODS: Twenty-four distal radius specimens were scanned with these two devices with a reconstructed voxel size of 75 µm for Newtom 5G and 82 µm for XtremeCT, respectively. A rescaling-registration scheme was used to define the common volume of interest. Cortical and trabecular compartments were separated using a semiautomated double contouring method. Density and microstructure were assessed with the HR-pQCT software on both modality images. RESULTS: Strong correlations were found for geometry parameters (r = 0.98-0.99), volumetric density (r = 0.91-0.99), and trabecular structure (r = 0.94-0.99), all p < 0.001. Correlations were lower for cortical microstructure (r = 0.80-0.89), p < 0.001. However, absolute differences were observed between modalities for all parameters, with an overestimation of the trabecular structure (trabecular number, 1.62 ± 0.37 vs. 1.47 ± 0.36 mm(-1)) and an underestimation of the cortical microstructure (cortical porosity, 3.3 ± 1.3 vs. 4.4 ± 1.4 %) assessed on CBCT images compared to HR-pQCT images. CONCLUSIONS: Clinical CBCT devices are able to analyze large portions of distal bones with good spatial resolution and limited irradiation. However, compared to dedicated HR-pQCT, the assessment of microarchitecture by NewTom 5G dental CBCT showed some discrepancies, for density measurements mainly. Further technical developments are required to reach optimal assessment of bone characteristics.

[Septic shock with multiple organ failure after returning from Southeast Asia]. / Choc septique avec défaillance multiviscérale au retour d'Asie du Sud-Est.

For a patient recently returned from a tropical country in intensive care, the leading hypothesis for a fever leading to multiple organ failure is evidently malaria. Nonetheless, many other causes are possible and should be considered: parasites, viruses, and bacteria. A multidisciplinary discussion between specialists in emergency medicine, radiology, pathology, and infectious diseases is essential to start appropriate treatment as quickly as possible without impairing the patient's prognosis.

[Combined variable immunodeficiency with unusal features. A case report]. / Présentation atypique d'un déficit immun commun variable. À propos d'un cas.

INTRODUCTION: The association granulomatosis - combined variable immunodeficiency (CVID) - is well known from the clinicians. However, the association with a large granular lymphocyte (LGL) leukemia has not been yet reported. CASE REPORT: We report a 50-year-old woman, followed for CVID associated with a granulomatous disease. During the follow-up, the patient developed a granulomatous lymphocytic interstitiel lung disease (GLILD). Secondarily, she presented a LGL leukemia. CONCLUSION: To our knowledge, this is the first reported case of an association between CVID and LGL leukemia.

[Delayed haemolytic transfusion reaction due to anti-JK1 antibody]. / Accident hémolytique retardé post-transfusionnel par allo-immunisation anti-JK1.

INTRODUCTION: The sensitivity of the detection of irregular antibodies (DIA) is one of the fundamental basis of transfusion safety. The production of alloantibodies is the first cause of adverse events following transfusion. CASE REPORT: We report a 77-year-old woman who was transfused and presented with a delayed haemolytic anemia due to anti-JK1 alloimmunization. This event highlights the limits of DIA performed before a transfusion, the hazard of this specific type of antibody and the difficulties of the diagnosis of haemolytic anaemia. The preventive measures necessary to avoid this undesirable effect are reminded. CONCLUSION: Despite the sensitive routine test method, the anti-JK1 antibodies could be missed. We should keep in mind the possibility of an anaemia due to alloantibodies we confronted to an unexplained haemolytic episode.