[Retroperitoneal fibrosis in adults: Main characteristics and relevance of the diagnostic procedures based on a retrospective multicenter study on 77 cases]. / Fibrose rétropéritonéale de l'adulte : analyse descriptive et évaluation de la pertinence des examens complémentaires réalisés à visée diagnostique à partir d'une série rétrospective multicentrique de 77 cas.

INTRODUCTION: Retroperitoneal fibrosis (RPF) is a rare disorder characterized by the sheathing of retroperitoneal structures by fibro-inflammatory process. It can be either isolated or associated with an underlying disease or condition. In the absence of consistent and consensual approach, the objective of this study was to assess the relevance of diagnostic tests performed during the diagnostic work-up of RPF. METHODS: Seventy-seven patients were included in this retrospective multicenter study. The diagnosis of RPF was defined by the presence of a thickened circumferential homogeneous tissue unsheathing the infrarenal aorta, excluding peri-aneurysmal fibrosis and a clear evidence of a cancer. RESULTS: In 62 cases (80.5%), the RPF was considered as being primary or "idiopathic". Surgical (n=31) or CT-guided (n=9) biopsies of the RPF were performed in half of the patients showing some fibrotic or non-specific inflammatory lesions in 98% of cases. A bone marrow biopsy was performed in 23 patients leading to diagnosis of low grade B cell non-Hodgkin lymphoma in a single patient who also had a monoclonal gammopathy IgM. The systematic search for autoantibodies or serum tumor markers was of no diagnostic value. CONCLUSIONS: Although the diagnostic procedure was heterogeneous, no cause or associated disease was found in the majority of cases of FRP in this series. In the absence of any clinical or paraclinical evidence suggesting an underlying disease or any atypical features at presentation, a number of non-invasive tests (autoantibodies, tumor markers, bone scintigraphy) and also more invasive diagnostic tests (bone marrow and RPF biopsies) seem of little relevance.

[Idiopathic retroperitoneal fibrosis: a multicentric retrospective study of 30 French cases and follow-up of the renal function]. / Fibrose rétropéritonéale idiopathique : évolution à long terme du pronostic rénal dans une série rétrospective multicentrique de 30 cas.

PURPOSE: Idiopathic retroperitoneal fibrosis (IRF) is an inflammatory disorder, affecting the aorta and the surrounding vessels and tissues. The prognosis is mainly driven by the risks of chronic kidney disease and relapse. Our aim was to assess the prevalence of chronic kidney disease at follow-up. METHODS: We retrospectively reviewed the medical records of patients diagnosed for IRF in Seine-Saint-Denis (France) between 1987 and 2011. We collected informations about presentation, radiologic findings and follow-up. Diagnosis of IRF was confirmed when all the following criteria were met: infiltration of the infrarenal aorta or iliac vessels, absence of aneurysmal dilation, lack of clinical suspicion of malignancy. RESULTS: Thirty patients were identified, with a male/female ratio of 4.9. Mean age was 55±13 years old. The mean creatinine clearance was 66 mL/min/1.73 m(2) and the mean CRP was 45±36 mg/L. In 24 (80%) patients, the location of IRF was periaortic and periiliac. Eleven patients (37%) underwent a diagnostic biopsy, and 14 (47%) required an ureteral procedure. A mean follow-up of 63 months was available for 29 patients: 69% relapsed, 7 developed chronic renal disease (24%), and one died of urinary sepsis. Older age (P=0.023), diabetes (P=0.007), and initial renal insufficiency (P=0.05) were associated with a risk of chronic renal insufficiency. CONCLUSION: The high frequency of relapses and chronic renal disease emphasizes the need of close follow-up in patients diagnosed with IRF.

[Pregnancy in a patient with Gitelman syndrome: a case report and review of literature]. / Syndrome de Gitelman et grossesse: à propos d'un cas et revue de la littérature.

Gitelman syndrome (GS) is a tubulopathy characterized by hypokaliemia, hypomagnesiemia, metabolic alkalosis and hypocalciuria. We report a case of a 33-year-old pregnant woman with Gitelman Syndrome. Oral potassium chloride and magnesium citrate were prescribed and the course of the pregnancy was uneventful with vaginal delivery at term. The impact of GS on the physiologic adaptations to pregnancy is not well-known, with few reports to date. Monitoring of serum potassium and magnesium levels with supplementation, amniotic fluid and fetal growth is required to prevent obstetrical and fetal complications in a patient with GS.

Regulation by glucocorticoids of expression and activity of rBSC1, the Na+-K+(NH4+)-2Cl- cotransporter of medullary thick ascending limb.

To assess whether glucocorticoids regulate rBSC1, the apical Na(+)-K(+)(NH(4)(+))-2Cl(-) cotransporter of kidney medullary thick ascending limb (MTAL), studies were performed in normal rats, adrenalectomized (ADX) rats, and ADX rats infused with dexamethasone for 6 days. The effects of dexamethasone on rBSC1 were also studied in vitro using isolated rat MTAL segments. Cotransport activity was estimated by intracellular pH measurements; rBSC1 protein was quantified in MTAL crude membranes by immunoblotting analysis, and mRNA was quantified by quantitative reverse transcription-polymerase chain reaction. The abundance of rBSC1 protein and mRNA increased in ADX rats infused with dexamethasone compared with ADX rats (p < 0. 04). In addition, application of dexamethasone for 1-3 h to MTALs caused rBSC1 protein and mRNA abundance and cotransport activity to significantly increase in a hyperosmotic medium (450 mosmol/kg of H(2)O) containing 0.7 nm arginine vasopressin, which is an in vitro experimental condition that resembles the in vivo MTAL environment. Results obtained in various media and with 8-bromo-cAMP indicated that stimulation of rBSC1 expression by glucocorticoids required interactions between glucocorticoid receptor- and cAMP-dependent factors. Up to 100 nm d-aldosterone had no effect on cotransport activity in vitro. Thus glucocorticoids directly stimulate MTAL rBSC1 expression and activity, which contributes to glucocorticoid-dependent effects on the renal regulation of acid-base balance and urinary concentrating ability.

Supportive treatment improves survival in multivisceral cholesterol crystal embolism.

Disseminated cholesterol crystal embolism (CCE) is a devastating complication of atherosclerosis that is often considered beyond therapeutic resources. We designed and implemented a treatment protocol based on an analysis of the main causes of death in disseminated CCE with renal involvement. From 1985 to 1996, we applied this protocol in 67 consecutive atherosclerotic patients admitted to our renal intensive care unit for acute renal failure (serum creatinine level, 6 +/- 2.5 mg/dL) accompanied by signs and symptoms of CCE. The other principal clinical features in these patients were cardiac failure with pulmonary edema (61%), gastrointestinal ischemia (33%), cutaneous ischemia (90%), and retinal cholesterol embolism (22%). Disseminated CCE followed one or several precipitating factors, including angiographic procedure(s) (85%), anticoagulant treatment (76%), and cardiovascular surgery (33%). Our treatment schedule systematically addressed the identified causes of death in these patients. (1) To avoid CCE recurrence, any form of anticoagulant treatment was withdrawn, and aortic catheterization and surgery were proscribed. (2) To treat or prevent cardiac failure, a high-dose vasodilator regimen was instituted, including angiotensin-converting enzyme (ACE) inhibitors. In case of cardiac failure refractory to vasodilators, loop diuretics were added and, if necessary, overhydration was corrected by ultrafiltration/hemodialysis (11 patients). (3) To avoid cachexia, severe metabolic disorders were treated by hemodialysis (41 patients), and special attention was given to providing enteral or parenteral nutritional support. Patients with declining general status and laboratory evidence of inflammation, as well as those with new episodes of CCE, were treated with corticosteroids. Statistical analysis found a significant correlation between the requirement for hemodialysis and previous anticoagulation, degree of renal insufficiency, and severity of cardiac failure. Conversely, there was no correlation between requirement for hemodialysis and ACE inhibitor treatment or presence of atherosclerotic renal artery stenosis/thrombosis. The inhospital mortality rate was 16%. There were no clinical or laboratory elements found on admission that were predictive of inhospital mortality. Among survivors, 32% had to remain on maintenance hemodialysis therapy for irreversible chronic renal failure. Including initial hospitalization, the 1-year survival rate was 87%, which compares favorably with reports in the literature indicating a first-year mortality rate of 64% to 81%. Overall follow-up was 19 +/- 20 months, ranging from 1 to 74 months. The 4-year survival rate was 52%. We conclude that an intensive-care, specific-treatment schedule reduces mortality in multivisceral cholesterol embolism.

[Cholesterol crystal embolism during treatment with low-molecular-weight heparin]. / Embolies de cristaux de cholestérol au cours de traitements par héparine de bas poids moléculaire.

BACKGROUND: Cholesterol crystal embolism is often an iatrogenic complication in ulcerated atherosclerosis of the aorta. CASE REPORTS: Two cases of multi-organ embolism of cholesterol crystals were histologically proven in patients treated with low-molecular-weight heparin. Both patients had acute renal failure, hypertension with acute pulmonary edema, skin necrosis and ischemia of the digestive tract. Outcome was favorable after discontinuing anticoagulants, symptomatic treatment, definitive hemodialysis and low-dose corticosteroids. DISCUSSION: These two cases are the first reported in the literature of cholesterol crystal embolism occurring during prophylactic treatment with low-molecular-weight heparin. They demonstrate that there is a risk of severe cholesterol embolism in high-risk patients after administration of low-molecular-weight heparin as for non-fractionated heparin, fibrinolytics, arteriography and cardiovascular surgery. Low-molecular-weight heparin thus should not be used in patients with a diagnosis of cholesterol crystal embolism.

Sulfadiazine-induced crystalluria in AIDS patients with toxoplasma encephalitis.

Toxoplasma encephalitis is the most common opportunistic infection of the central nervous system in patients with AIDS. The treatment of choice is a combination of sulfadiazine and pyrimethamine. We present here four patients with AIDS treated for toxoplasmic encephalitis who developed sulfadiazine-induced crystalluria. This complication was rapidly reversible with rehydration and urine alkalinization. Patients with AIDS treated with high doses of sulfadiazine should be adequately hydrated, and their urinary pH maintained above 7.5 to prevent sulfadiazine-induced crystalluria.