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991.
Hematopoietic Stem Cell Transplant (HSCT) causes immunosuppression and predisposition to sinusitis. CT scans are complementary exams used in the diagnosis of sinusitis; however, its use in every patient is questionable.Aimto check the usefulness of ordering a CT scan prior to HSCT and to study the relationship between anatomical variations and sinusitis.Methodprospective study in which we performed paranasal CT scans before and after HSCT, using the Lund and Mackay score.Results77.5% and 61% of CT scans showed no evidence of sinus disease before and after HSCT. CT staging was not associated with sinusitis after HSCT. Anatomical variations were related to radiographic disease severity, but not to development of sinusitis after HSCT. There was no relation between pre-CT staging and sinusitis after BMT.ConclusionCT scans are not useful for all patients before HSCT. Anatomical variation is not a predictive feature to sinusitis but it can determine its severity.  相似文献   
992.
The sacrum is a structure that is imaged by both general and subspecialty radiologists. A wide variety of disease processes can involve the sacrum either focally or as part of a systemic process. Plain radiographs, although limited in evaluation of the sacrum, should be carefully examined when abnormalities of the sacrum are suspected. Cross-sectional imaging, particularly computed tomography and magnetic resonance (MR) imaging, plays a crucial role in identification, localization, and characterization of sacral lesions. Congenital lesions of the sacrum, including sacral agenesis and meningocele, are optimally imaged with MR. The most common sacral neoplasm is metastatic disease. Primary neoplasms of the sacrum, which include giant cell tumor, chordoma, and teratoma, are infrequent. Infection of the sacrum or sacroiliac joint is most often due to contiguous spread from a suppurative focus. A wide variety of arthritic disorders such as ankylosing spondylitis and osteoarthritis can involve the sacroiliac joints as part of a localized or systemic process. Sacral fractures related to acute trauma or repetitive stress are difficult to diagnose and treat. Knowledge of these abnormalities and familiarity with the imaging of these processes will allow radiologists of all subspecialties to contribute to the diagnosis and management of sacral disorders.  相似文献   
993.
The risks and benefits of structured treatment interruption (STI) in HIV-1-infected subjects are not fully understood. A pilot study was performed to compare STI with continuous highly active antiretroviral therapy (HAART) in chronic HIV-1-infected subjects with HIV-1 plasma RNA levels (VL) <400 copies per ml and CD4(+) T cells >400 per microl. CD4(+) T cells, VL, HIV-1-specific neutralizing antibodies, and IFN-gamma-producing HIV-1-specific CD8(+) and CD4(+) T cells were measured in all subjects. STIs of 1-month duration separated by 1 month of HAART, before a final 3-month STI, resulted in augmented CD8(+) T cell responses in all eight STI subjects (P = 0.003), maintained while on HAART up to 22 weeks after STI, and augmented neutralization titers to autologous HIV-1 isolate in one of eight subjects. However, significant decline of CD4(+) T cell count from pre-STI level, and VL rebound to pre-HAART baseline, occurred during STI (P = 0.001 and 0.34, respectively). CD4(+) T cell counts were regained on return to HAART. Control subjects (n = 4) maintained VL <400 copies per ml and stable CD4(+) T cell counts, and showed no enhancement of antiviral CD8(+) T cell responses. Despite increases in antiviral immunity, no control of VL was observed. Future studies of STI should proceed with caution.  相似文献   
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CT-guided percutaneous radiofrequency ablation and laser photocoagulation have become the methods of choice for the treatment of all osteoid osteomas except those in contact with neural structures.We report 10 patients with spinal osteoid osteoma adjacent to the neural elements treated with 12 sessions of CT-guided monopolar radiofrequency ablation. The size range of the lesion was 3-14 mm (mean, 7.5 mm) and the distance between the nidus and the adjacent spinal cord or nerve root was 2-12 mm (mean, 5 mm). No intact cortex between the tumor and the spinal cord or nerve roots constituted an exclusion criterion because of a higher risk of undesirable neurotoxic effects.Patients were under general anesthesia. After location of the lesion, a 11G-bone biopsy was introduced into the nidus. The radiofrequency electrode was inserted through the biopsy needle and heated at 90 °C for 4 min.Primary success was obtained in eight patients.At follow-up (mean, 19.5 months; range, 6-24 months), pain persisted in two patients after 2 months. Both of them were re-treated. All patients are currently pain-free and complications were not detected.In our opinion, radiofrequency ablation can also be considered the treatment of choice for spinal osteoid osteoma.  相似文献   
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Atypical mycobacterial infections are increasingly important in immunosuppressed patients as well as in healthy hosts. The atypical mycobacterium that most commonly affects the skin is Mycobacterium marinum. The infection should be suspected upon the presence of ulcers, nodules or chronic plaques and a history of contact with fresh or salt water. Optimal therapy is yet to be established. We report a case of Mycobacterium marinum infection in a patient receiving immunosuppressive therapy that responded favourably to treatment with doxicycline. We review the different antibiotic regimens prescribed in the past years for the treatment of Mycobacterium marinum infection.  相似文献   
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