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J Rossert

Publications and source records attributed to J Rossert.

60 records · Page 4Linked to original sources
PubMedDate not supplied

MR-Guided PTA in experimental bilateral rabbit renal artery stenosis and MR angiography follow-up versus histomorphometry.

PURPOSE: To assess in vivo 1) MR-guided percutaneous transluminal renal angioplasty (PTRA) in experimental bilateral rabbit renal artery stenosis (RAS); 2) postprocedural follow-up by gadolinium-enhanced MR angiography versus histomorphometry. METHODS: Fifteen male NZW rabbits of mean weight 4.0 kg (range 3.5-4.2 kg) underwent bilateral RAS induction by combined overdilation-deendothelialization with a gadolinium-filled balloon, passively MR-guided by the artifact of a 0.014-inch guidewire. After 4 weeks the rabbits were randomized into two groups: group A (n = 8) underwent right-sided PTRA for treatment of RAS, group B (n = 7) underwent left-sided PTRA. After another 4 weeks the rabbits were killed to assess by histomorphometry recurrent stenosis and contralateral induction injury stenosis lesions. Each step was preceded by gadolinium-enhanced three-dimensional MR angiography, and the cortex-to-aorta (C/A) signal intensity ratio was calculated. RESULTS: RAS induction was successful in all cases. Fourteen arteries developed restenosis and 13 only initial stenosis. MR-guided PTRAs were feasible in 22 arteries (73%). For a successful catheterization of the ostium (20 arteries, 66% success rate), 10-25 steps were required. Five to eight steps were required for balloon localization and inflation for each PTRA. The restenosis effect was reflected by a 16% (12%-27%) decrease in C/A values on MR angiograms (p < 0.05). CONCLUSION: MR guidance and MR angiography represent a feasible, less invasive alternative for performing and assessing experimental PTRA in RAS.

Angioplasty, Balloon↗
PubMedDate not supplied

Increased risk of Pneumocystis carinii pneumonia in patients with Wegener's granulomatosis.

Combining cyclophosphamide (Cy) and corticosteroids has dramatically improved the prognosis of Wegener's granulomatosis (WG). But this treatment carries the risks of severe infectious complications and drug toxicity. During a 10-month period, we observed 6 cases of Pneumocystis carinii pneumonia (PCP) in 23 patients with biopsy-proven WG and renal involvement. These 23 patients were enrolled in a multicenter controlled clinical trial designed to evaluate the efficacy and safety of either intermittent high-dose pulse Cy or daily oral low-dose Cy in combination with oral prednisone. Mean delay of onset of PCP was 2.5 months after the beginning of the immunosuppressive therapy. In all cases, the diagnosis of PCP was established by cytological examination of bronchoalveolar lavage fluid. None of the patients experienced severe leukopenia at the time of diagnosis, but the mean lymphocyte count decreased to 495/mm3 (range 100 to 830/mm3) and 2 patients had inverted CD4/CD8 T-cell ratios. Renal function was significantly impaired (creatininemia = 493.5 vs 195.4 micromol/l; p = 0.03) in the 6 patients presenting PCP vs those without. High-dose co-trimoxazole therapy was successful in 3 patients, but 3 others who required mechanical ventilation died. Treatment of WG with daily prednisone and either pulse or oral Cy may have contributed to higher rates of PCP in the past than previously thought and, therefore, patients currently receiving such a regimen may be at greater risk for PCP. For these patients, this opportunistic infection must remain highly suspect in order to reach a diagnosis earlier and rapidly initiate treatment. In addition, recommendations for prophylactic therapy are needed.

Adrenal Cortex Hormones↗