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David Saadoun

Publications and source records attributed to David Saadoun.

22 records · Page 2Linked to original sources
PubMed2003

CD4+CD25+ regulatory T-cell deficiency in patients with hepatitis C-mixed cryoglobulinemia vasculitis.

Patients who are chronically infected with hepatitis C virus (HCV) often develop mixed cryoglobulinemia (MC), a B-cell proliferative disorder with polyclonal activation and autoantibody production. We investigated if MC is associated with a deficit of CD4(+)CD25(+) immunoregulatory T (Treg) cells, which have been shown to control autoimmunity. Because Treg cells express higher amounts of CD25 than activated CD4(+) T cells, we analyzed blood CD4(+)CD25(high) Treg cells in 69 untreated patients chronically infected with HCV. Treg cell frequency in patients without MC (8.8% +/- 2.3%) or with asymptomatic MC (7.4% +/- 2.1%) was comparable to that of healthy controls (7.9% +/- 1.3%). In contrast, it was significantly reduced in symptomatic MC patients (2.6% +/- 1.2%, P <.001) even when compared to a panel of untreated HCV(-) patients with different inflammatory disorders (6.2% +/- 0.8%, P <.0001). In symptomatic MC patients, the purified remaining CD4(+)CD25(+) T cells retained suppressive activity in vitro. These results, together with experimental data showing that depletion of Treg cells induces autoimmunity, suggest a major role of Treg cell deficiency in HCV-MC vasculitis and this is the first report of a quantitative Treg cell deficiency in virus-associated autoimmunity.

Adult↗
PubMed2003

Chronic lithium nephropathy: MR imaging for diagnosis.

PURPOSE: To evaluate the appearance of lithium nephropathy at magnetic resonance (MR) imaging. MATERIALS AND METHODS: Sixteen patients with renal insufficiency and clinical and laboratory evidence of nephropathy secondary to therapy with lithium salts were examined with a 1.5-T MR imaging unit with T1-weighted, T2-weighted fast imaging with steady-state precession (true FISP), rapid acquisition with relaxation enhancement, half-Fourier turbo spin-echo, and gadolinium-enhanced (FISP three-dimensional MR angiographic) sequences. Renal size and the presence, number, location and size of parenchymal cysts were analyzed. The cysts in each kidney were defined as rare (fewer than 10 cysts), sparse (between 10 and 30 cysts), abundant (30-60 cysts), or very abundant (more than 60 cysts). RESULTS: The mean length of both kidneys was 104 mm +/- 9 in seven cases, and one or both kidneys were less than 90 mm in length in nine cases. Renal microcysts measuring from 1 to 2 mm were detected in all patients. They were either very abundant (n = 12), abundant (n = 2), or sparse (n = 2). The cysts were located with equal abundance in both the cortex and the medulla in 11 cases and were predominantly located in the renal cortex in five cases. No renal artery stenosis was present. CONCLUSION: Microcysts secondary to long-term lithium therapy can be detected with MR imaging.

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