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Biomedical subjects

J Pourrat

Publications and source records attributed to J Pourrat.

At least 19 recordsLinked to original sources
PubMed1994

Treatment of polyarteritis nodosa related to hepatitis B virus with interferon-alpha and plasma exchanges.

OBJECTIVES: To test the effectiveness of and tolerance to interferon-alpha 2b (INFa2b) in association with plasma exchanges for the treatment of polyarteritis nodosa (PAN) related to hepatitis B virus (HBV). METHODS: A prospective, non blinded, multicentre trial was carried out in which patients with multisystemic HBV-related PAN were included. Each patient received the association of INFa2b and plasma exchanges. The end point of the study was control of the disease (recovery or remission) or death. RESULTS: Six patients were included in the study. Each patient had histopathological or arteriographic evidence of vasculitis and was infected with actively replicating HBV. All patients were alive at the end of the study and no longer presented clinical or laboratory evidence of systemic vasculitis. HBeAg/anti-HBeAb seroconversion was observed in four patients (66.6%) and HBsAg/anti-HBsAb in 3/6 (50%). Two patients are still being treated with INFa2b because of chronic active hepatitis. CONCLUSIONS: It is considered that this new therapeutic approach to HBV-related PAN effectively cured systemic vasculitis and was associated with control of HBV infections. Antiviral therapy may have a role to play as the first line treatment regime of virus-induced vasculitis.

Adult↗
PubMed1994

[Nodular and granulomatous form of periarteritis nodosa caused by the hepatitis B virus].

Polyarteritis nodosa (PAN) is, in rare cases, associated with subcutaneous nodules and pathology does not usually show the presence of peri and extravascular granulomas. When present in patients with hepatitis B virus (HBV) related PAN these facts demonstrate that classification of PAN is not homogeneous. CASE REPORT. A patient infected by HBV developed a PAN demonstrated by clinical symptoms and pathology. The disease was characterized by the presence of subcutaneous nodules and histologically by peri- and extra-vascular granuloma which surrounded necrosis of medium-sized vessels. Outcome was also unusual in the patient who did not respond to the association of plasma exchanges and antiviral agents and was only slightly improved by steroids and cyclophosphamide. COMMENTS. HBV-related PAN is considered to be an immune complex disorder. In the present case report granuloma were present as observed in Churg Strauss syndrome or Wegener's granulomatosis which are the consequence of other pathogenetic mechanisms as anticytoplasmic neutrophil antibodies (ANCA). This case reports underlines the heterogeneity of the PAN group of vasculitis and the probable role for various pathogenetic mechanisms.

Antiviral Agents↗
PubMed1993

Antineutrophil cytoplasm antibodies in systemic polyarteritis nodosa with and without hepatitis B virus infection and Churg-Strauss syndrome--62 patients.

OBJECTIVE: Antibodies directed against components of neutrophil cytoplasm have been detected in various systemic vasculitides and especially in Wegener's granulomatosis. In polyarteritis nodosa (PAN) and Churg-Strauss syndrome, few data are available and correlation between clinical manifestations and antineutrophil cytoplasm antibodies (ANCA) has not been established. Therefore, we tested, before treatment of vasculitis, 62 consecutive patients suffering from PAN with hepatitis B virus (HBV) markers, PAN of unknown etiology or Churg-Strauss syndrome. METHODS: Only patients with PAN and Churg-Strauss syndrome were included in the study. The diseases were histologically and/or angiographically proven. Every patient's serum was tested by an indirect immunofluorescence assay (IFA) and, in 37 cases, by an enzyme linked immunosorbent assay (ELISA). RESULTS: ANCA detected by IFA were observed in 10.7% of the patients with PAN with HBV markers, in 27.3% of the patients with PAN without HBV markers and in 66.7% of the patients with Churg-Strauss syndrome. When ELISA was performed, 11.1% of the patients with PAN associated with HBV infection, 20% of the patients with PAN without HBV markers and 55.6% of the patients with Churg-Strauss syndrome were positive. ANCA were positively correlated with asthma and purpura and negatively correlated with HBV markers. CONCLUSION: Regardless of the technique used, Churg-Strauss syndrome was associated with ANCA in about 60% of the cases while, in PAN of unknown etiology, ANCA were found in about 25% of cases. In contrast, IFA and ELISA only detected ANCA in a limited number of cases of PAN related to HBV infection. ELISA positivity in patients with PAN and Churg-Strauss syndrome was usually associated with antimyeloperoxidase antibodies. In our cases of PAN, ANCA and purpura were significantly correlated, suggesting that, in these cases, small vessels are involved and therefore macroscopic and microscopic PAN coexist. Thus it seems that ANCA are essentially present in the cases of small vessel vasculitis, as has been described, and are not a marker of pure macroscopic PAN, at least at our present level of understanding of these antibodies.

Adult↗
PubMed1993

[Microscopic polyarteritis].

Microscopic polyarteritis is an idiopathic necrotising vascularitis of the small vessels. Manifestations include diffuse alveolar haemorrhage, segmentary necrotising glomerulonephritis, and a cutaneous, articular, neurological or digestive vascularitis. The absence of a histological granulomas and medium calibre vessel involvement distinguishes Wegener's syndrome from polyarteritis nodulosa. The diagnosis is facilitated when anti-neutrophil cytoplasm antibodies are found in the serum. These auto-antibodies are suspected to be the cause based on clinical and experimental data, although this aetiology has not been confirmed. Corticosteroids, immunosuppressors and plasmapheresis can improve the prognosis of this severe and evolving affection which may be fatal.

Adrenal Cortex Hormones↗
PubMed1992

[Anti-polynuclear neutrophil cytoplasmic antibodies of the perinuclear type or p-ANCA].

Some neutrophil cytoplasmic auto-antibodies produce perinuclear immuno staining of alcohol-fixed neutrophils called P-Anca pattern. These autoantibodies show chiefly reactivity with myeloperoxidase in Elisa but other specificities have been detected (elastase, cathepsin, lactoferrin). These P-Anca anti-MPO are more frequent with renal angiitis but P-Anca (anti-MPO negative) are associated with other diseases without renal failure (rheumatoid arthritis, Gougerot-Sjogren and ulceritis colitis).

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1990

[Renal involvement in rheumatoid polyarthritis].

Urinary disorders were investigated in 162 patients with specific or standard rheumatoid disease, over a period of 5 years. 43 patients presented disturbances of the urinary laboratory tests, or 26.5 p. cent and 17 of them underwent a renal needle-biopsy. The findings were as follows: 11 isolated proteinurias, iatrogenic and reversible when the treatment in question was discontinued (gold salts, D-penicillamine), 13 microscopic hematurias, 3 isolated leucocyturias, 3 combinations hematuria-leucocyturia, 3 combinations hematuria-leucocyturia-proteinuria, 6 nephrotic syndromes including 5 of iatrogenic origin, 4 isolated renal failures. The most interesting discussion concerns microscopic hematurias. Besides the standard lesions of extra-membranous glomerulonephritis, amyloidosis and interstitial nephritis, 50 p. cent of the renal histologic examinations corresponded to lesions of mesangial glomerulonephritis. This lesion seems unrelated to long-term treatments and could be encouraged by the chronic inflammatory condition of the rheumatoid disease.

Adolescent↗
PubMed1990

Treatment of progressive systemic sclerosis by plasma exchange: long-term results in 40 patients.

The efficacy of plasma exchanges (PE) during the course of scleroderma has only been investigated for short periods. The aim of this study was to follow patients over a long enough period to observe the course of the clinical and paraclinical symptoms in the short, medium, and long term. Forty patients, 24 women and 16 men, were treated by PE and observed for 1-3, 3-12 and over 12 months. Immunological, biological and clinical course and any undesirable side effects were evaluated using a detailed questionnaire. Concomitant therapies were reported and most frequently consisted of corticosteroids, colchicine, factor XIII or vasodilators (nifedipine, captopril). The therapeutic effectiveness of PE was assessed on the basis of improvements in cutaneous, digestive, joint, muscular, lung, cardiovascular and renal lesions. Our findings confirmed the effectiveness of short-term PE on scleroderma (52% of the patients improved during the first 3 months). However, this improvement was transient (5% improvement between 3 and 12 months and only 2.5% over 12 months) and limited to the cutaneous and muscular lesions. Thus, PE cannot be recommended for the treatment of progressive systemic sclerosis.

Adolescent↗
PubMed1984

[Gynecomastia and chronic renal insufficiency in periodic hemodialysis. Demonstration of a decrease in the free fraction of testosterone].

Gynecomastia is frequently observed in male patients undergoing hemodialysis; however, its mechanism is still unclear. Hormonal studies were performed in a group of 39 men, aged 50 +/- 14 years, dialysed for 2.8 +/- 2 years. 23 (59 p. 100) of them had gynecomastia. Peripheral hypogonadism and hyperprolactinemia were found in all the hemodialysed patients. Whether gynecomastia was present or not, no significant difference was observed for gonadotropins, prolactin, testosterone, estradiol 17 beta and testosterone-estradiol binding globulin levels. In contrast, the urinary output (p less than 0,05) and free testosterone (p less than 0,05) were significantly lower in the group with gynecomastia. Gynecomastia occurring in hemodialysed patients is probably due to a decrease of the testosterone/estrogen ratio. If so, percutaneous treatment with 5 alpha dihydrotestosterone might improve this type of gynecomastia.

Adult↗
PubMed1984

Metastases of human tumor xenografts in nude mice.

In the present study, using systematic microscopic examination, we tried to determine the true incidence of metastases in nude mice bearing a wide variety of human tumors. A total of 63 malignant tumors were successfully transplanted subcutaneously and 831 nude mice bearing tumors were examined. It appeared that 17 of the 63 tumors (26.9%) retained their metastatic ability in nude mice. Most of these tumors were adenocarcinomas (11/17 cases). Generally the metastatic deposits in the lungs and, to a lesser extent, in the lymph nodes were small and thus only detectable on microscopic examination. We also found a positive correlation between the presence of metastases and neoplastic infiltration of the lymphatic and/or blood vessels around the subcutaneous tumors. Metastatic human tumors, including neoplastic cells from effusion, exhibited higher metastatic ability than primary tumors (p less than 0.005). However, the expression of this metastatic potential depends on several factors including tumor volume, survival time after inoculation and murine hepatitis infection. Thus, animals with metastases bore larger tumors (9.56 cm3) than those without metastasis (6.35 cm3; p less than 0.0001). Moreover, survival time after inoculation was longer in mice with metastases (104 days) than in mice without metastases (81 days; p less than 0.0001). A negative influence of viral hepatitis on the incidence of metastases was observed. This may simply be related to the shortened life span of the animals. Death due to this infection may precede the expression of the metastatic potential.

Animals↗