Search PubMed⌕ Search

Biomedical subjects

A Pruna

Publications and source records attributed to A Pruna.

At least 19 recordsLinked to original sources

[Association of Wolff-Parkinson-White syndrome with isolated non-compaction of the left ventricle: a case report].

The Wolff-Parkinson-White syndrome (WPW) may be associated with a number of cardiac pathologies, especially congenital disease, in 7.5 to 17% of cases. The authors report a rare association of the WPW syndrome with two Kent bundles, right and left septal, with non-compaction of the left ventricle in a 52 year old man. This was a chance finding during systematic echocardiography after ablation, and confirmed by cardiac MRI. The patient was asymptomatic.

Catheter Ablation↗

[Collapsing glomerulopathy and cytomegalovirus, what are the links?].

BACKGROUND: Collapsing glomerulopathy is a form of focal and segmental glomerulosclerosis which occurs preferentially in black people. It causes severe nephrotic syndrome and quickly progresses towards end-stage renal failure. CASE REPORT: We report the case of a 16-year-old black girl from Guadeloupe who was admitted for tetanus and edema in 1996. She had hypoparathyroidism, renal failure and a nephrotic syndrome as well as cytomegalovirus infection. Renal biopsy showed collapsing glomerulopathy. The renal function improved on glucocorticoid and ganciclovir therapy and her serum creatinine stabilized around 250 mumol/l for two years. DISCUSSION: Collapsing nephropathy is the cellular type of focal and segmental glomerulosclerosis. The main etiology is the human immunodeficiency virus. A viral infection may be involved in its pathogenesis. Other viruses could be linked with this nephropathy. This case report relates a case associated with a cytomegalovirus viruria. The clinical course might be related with the antiviral treatment.

AIDS-Associated Nephropathy↗

[Renal and hypertensive complications of extracorporeal lithotripsy].

HISTOLOGICAL AND FUNCTIONAL CONSEQUENCES OF ESWL: Extracorporeal shock wave litotripsy is now used for the treatment of about 90% of stones. Because of the nonpunctual delivery of energy into the stone, a small volume of renal parenchyma is injured, giving rise to a fibrous scar which can be visualized by morphological techniques such as magnetic nuclear resonance. Isotopic techniques point out a 15% reduction of renal plasma flow on the side of the litotripsy. For a majority of patients, this alteration is transient. HYPERTENSION: In a few cases, abrupt onset of transient hypertension has been reported in clear relation with a compressive perirenal hematoma. The causal effect of ESWL on late occurrence of permanent hypertension is however still uncertain, probably because of the difficulty to show that this occurrence is not related to the older age of the patient alone. The FDA sponsored multicentric study begun in 1993 should solve this issue in the future. PATIENTS AT RISK: Recent articles suggest that altered renal function prior to ESWL would predict late occurrence of hypertension and worsening of renal failure. Furthermore, age and the resistance index of arcuate or interlobular renal arteries (measured by Doppler) could help to screen the patients at risk of developing hypertension. Practical attitude: In practice, renal function and blood pressure should be carefully monitored in patients aged over 60 and/or who have a serum creatinine > 300 mumol/l.

Acute Kidney Injury↗

Cyclosporine bone remodeling effect prevents steroid osteopenia after kidney transplantation.

BACKGROUND: It is well established that prednisone above 7.5 mg/day may induce osteopenia in association with decreased bone formation. In contrast, the effect of cyclosporine on bone remodeling and bone mineral density (BMD) is controversial. Multiple confounding factors explain this controversy, especially after renal transplantation. METHODS: Fifty-two renal transplanted patients never exposed to aluminum while on dialysis were selected because they had no rejection and no hypercalcemia for 24 months while being treated with low dose prednisone/cyclosporine A (daily dose at 10 mg and 4.8 mg/kg, respectively, beyond 3 months). Bone remodeling markers (BRMs; plasma osteocalcin, bone and total alkaline phosphatases for formation, and urinary pyridinolines for resorption) were sequentially measured together with plasma creatinine, intact parathyroid hormone (PTH) and 25 OH vitamin D and cyclosporine from day 0 to 24 months. BMD was measured at 3, 6, 12, and 24 months by quantitative computerized tomography (QCT) at the lumbar spine and by double-energy x-ray absorptiometry (DEXA) at this site, as well as at the femoral neck, radius shaft, and ultradistal (UD) radius. RESULTS: Plasma concentrations of creatinine, PTH, and 25 OH vitamin D initially decreased and stabilized beyond three months at 137 micromol/L, 1.5 the upper limit of normal (ULN) and 11 ng/mL, respectively. All BRM increased significantly above the ULN at six months and then decreased. The BMD Z score at three months was low at all sites measured by DEXA and QCT. Follow-up measurements showed stability of absolute value and of Z score at all sites measured by DEXA. A comparison of the lumbar QCT Z score, which was available in 42 patients at 3 and 24 months, showed an increase in 28 and a decrease in 14, so that the increase for the whole group was significant (P < 0.04). Compared with patients with a decreased Z score, those with an increased Z score had significantly higher cyclosporine and lower prednisone dosages and a greater BRM increase at six months, whereas age, sex ratio, and plasma creatinine, PTH and 25 OH vitamin D were comparable and stable from months 3 through 24. The mean trough level of cyclosporine for the first six months was positively correlated to osteocalcin and total alkaline phosphatase increase at six months, and both bone formation and resorption marker increases were significantly correlated to the lumbar QCT Z score increase at 24 months. CONCLUSIONS: Combined low-dose prednisone and cyclosporine immunosuppression are associated with a stabilization of BMD measured at all sites with DEXA 3 to 24 months after renal transplantation and with a prevention of age-related loss of vertebral trabecular bone, as shown by the significant increase in lumbar spine QCT Z score. It is suggested that cyclosporine, together with the decrease of prednisone dosage but independent of renal function, PTH, and vitamin D status, contributes to a transient stimulation of bone remodeling at six months, which counterbalances the deleterious effect of prednisone on bone formation and BMD.

Absorptiometry, Photon↗

[Renal osteodystrophy (1): invasive and non-invasive diagnosis of its pathologic varieties].

1. Renal osteodystrophy is a general term encompassing all the disturbances of the phosphocalcic metabolism and their associated bone and soft tissue abnormalities, which progressively occur in chronic renal failure. In this article we detail their main histopathological and etiopathogenic aspects as well as their invasive and non invasive diagnostic approach. 2. Osteitis fibrosa is characterized by extensive medullary fibrosis and osteoclastic hyperresorption linked to PTH hypersecretion. 3. Adynamic bone disease is mainly related to iatrogenic oversuppression of PTH secretion. It is favored by aluminum overload which directly inhibits the osteoblasts. It is characterized by a low bone formation rate without primary mineralization defect so that the osteoid seam thickness is normal or low, in contrast to osteomalacia in which by definition osteoid thickness is increased. 4. Osteomalacia is mainly due to aluminum intoxication, vitamin D insufficiency, hypocalcemia, acidosis and exceptionally to hypophosphatemia. 5. The differential diagnosis between the histopathological entities may be oriented on clinical, radiological and biochemical means. Only the bone biopsy can make the diagnosis with certainty. This latter is however necessary for appropriate treatment only in the patients who have been exposed to aluminum and who are symptomatic or hypercalcemic in order to distinguish severe osteitis fibrosa from aluminic bone disease, and more particularly from mixed osteopathy. Indeed surgical parathyroidectomy in patients with mixed osteopathy associating bone hyperremodeling and mineralization defect with inappropriately thick osteoid seam may induce fracturing low turn over aluminic bone disease.

Bone and Bones↗

Is low plasma 25-(OH)vitamin D a major risk factor for hyperparathyroidism and Looser's zones independent of calcitriol?

BACKGROUND: Recent reports suggest that calcitriol might not be the sole active metabolite of vitamin D and that plasma concentrations of 25-(OH)vitamin D (25OHD) are often abnormally low in hemodialysis patients. We have therefore evaluated plasma 25OHD as a risk factor for parathyroid hormone (PTH) hypersecretion and radiological bone disease. We carried out a cross-sectional study during the month of September in an Algerian dialysis center of 113 patients who were not taking supplements of alphacalcidol or calcitriol. METHODS: Plasma 25OHD, calcitriol, PTH, calcium, phosphate, bicarbonate, and aluminum were measured, and x-rays of the hands and pelvis were obtained for evaluation of subperiosteal resorption and Looser's zones. RESULTS: The median plasma 25OHD was 47.5 nmol/liter (range 2.5 to 170.0). Univariate analysis showed that plasma PTH was correlated positively with months on maintenance dialysis and negatively with plasma 25OHD, calcitriol, calcium, bicarbonate and aluminum, but not with that of phosphate. plasma 25OHD was positively correlated with calcium and calcitriol. Using multiple regression analysis, only plasma 25OHD (negative) and the duration on maintenance dialysis (positive) were independently linked to plasma PTH. The prevalence of isolated subperiosteal resorption (ISR) was 34%, and that of the combination of resorption with Looser's zones (CRLZ) was 9%; thus, only 57% of the patients had a normal x-ray appearance. These groups were comparable with regards to age, gender, and duration on dialysis. When the biochemical measurements of the patients with CRLZ were compared with those from patients without radiological lesions, plasma 25OHD was the only parameter to show a statistically significant difference, being significantly lower in the CRLZ group (26 +/- 18 vs. 57 nmol/liter, ANOVA, P < 0.004). Plasma 25OHD was also significantly lower in the ISR group (44, P < 0.05) than in the normal x-ray group, and plasma Ca (P < 0.003) and bicarbonate (P < 0.02) were lower. Logistical analysis showed that the presence of resorption was independently linked only with plasma PTH. Looser's zones and subperiosteal resorption were not seen in patients with plasma 25OHD of more than 40 (Looser's zones) and more than 100 nmol/liter (subperiosteal resorption). The optimal range for intact PTH in hemodialysis patients with mild aluminum overload is 10 to 25 pmol/liter. We found that plasma PTH was inappropriately high only when plasma 25OHD was less than 100 nmol/liter. With a plasma 25OHD of between 100 and 170 nmol/liter, hypercalcemia was present with a plasma PTH of less than 10 pmol/liter in only one case. CONCLUSIONS: This cross sectional study shows that low plasma 25OHD is a major risk factor for hyperparathyroidism and Looser's zones. In dialysis patients, we suggest that the plasma levels of 25OHD are maintained around the upper limit of the reference range of sunny countries.

Adult↗

Renal and hypertensive complications of extracorporeal shock wave lithotripsy: who is at risk?

Extracorporeal shock wave lithotripsy (ESWL) is now used in the treatment of about 90% of renal and ureteral stones. Because of the non-punctual delivery of energy to the stone, a small volume of renal parenchyma is injured giving place to a fibrous scar which can be shown by highly resolutive imaging techniques like magnetic nuclear resonance. Isotopic clearances point to a reduction of 15% in the renal plasma flow on the side of the lithotripsy, but this alteration appears to be transient in nature. In a few cases an abrupt onset of transient hypertension has been reported in clear relation to a compressive perirenal hematoma. The responsibility of ESWL in the late occurrence of permanent hypertension is, however, still uncertain, probably because of the difficulty in showing that this occurrence is not only related to the older age of the patient. The American Food and Drug Administration-sponsored multicentric study begun in 1992 should solve this issue in the future. Recent articles suggest that altered renal function prior to ESWL would predict the late occurrence of hypertension and worsening of renal failure. Furthermore, age and the resistance index of arcuate or interlobar renal arteries (measured by Doppler) could help to screen patients at risk of developing hypertension. In practice in patients over 60 years of age and/or with a plasma creatinine of >to 300 micromol/l, ESWL should be performed with caution, and renal function and blood pressure should be carefully monitored.

Animals↗

[Factors in the progression of renal insufficiency during the 2 years preceding the use of dialysis].

UNLABELLED: The respective contribution of sex, type of nephropathy, degree of proteinuria, blood pressure, protein and sodium daily intake, lipid profile, protidemia, hemoglobinemia, acidosis and CaPO4 product on the rate of renal failure progression is debated. The link between these parameters and the decrease of creatinine clearance, delta Ccr (according to Cockroft) was assessed in uni and multivariate analysis in a population of 49 patients (26 men, 23 women; age 60 +/- 15 years, weight 73 +/- 15 kg) selected out of 173 presently treated hemodialysis patients on the basis of availability of a quarterly follow-up for two years before starting dialysis. The patients were advised a moderate protein and salt restriction which could be retrospectively assessed (on urinary excretion of urea and sodium) at respectively 0.82 g/kg/day and 6.5 g/day. The two years delta Ccr was 14 +/- 14 ml/min. It was not different in men and women (specially when expressed in % of initial value). This decrease in Ccr was neither significantly different in glomerular disease (17 +/- 8, n = 14), diabetic nephropathy (12 +/- 6, n = 7), nephroangiosclerosis (15 +/- 8, n = 5), interstitial nephritis (12 +/- 10, n = 14), and PKD (11 +/- 12, n = 9). Patients with antihypertensive drugs (n = 42) had a faster progression than those without drugs (n = 7): delta Ccr = 15 +/- 14 vs 7 +/- 7 ml/min (p < 0.05) in spite of comparable blood pressure but with higher proteinuria. Linear regression of delta Ccr with the initial and two year averaged values of the quantitative parameters showed a significant positive link for both values with cholesterol, hemoglobin and proteinuria and a negative one with protidemia. A positive link was observed with the initial value of bicarbonate and the two year mean of diastolic and mean blood pressures. No link at all was observed with urea and Na excretion, CaPO4 product and triglycerides. Multiple regression disclosed a significant link only for protidemia (negative with both initial and two years averaged value), diastolic BP (only for the two year averaged value and hemoglobinemia (for the initial value). When the patients were classified according to a threshold value of their protidemia, DBP, hemoglobinemia, and cholesterolemia those with the combination of two risk factors of progression (pro-tidemia < 66 g/l, DBP > or = 90 mmHg, hemoglobinemia > 11 g/dl, proteinuria > 3g/d, CT > 5 mmol/l) had a significantly greater decrease of Ccr than those with the three other combinations at the exception of the association of low protidemia with DBP. CONCLUSION: 1. diastolic hypertension and low protidemia are the two most important factors predicting progression of renal failure; 2. a predictive synergy was furthermore pointed out between on one hand low protidemia and diastolic hypertension and on the other hand proteinuria and cholesterol; 3. on the contrary, anemia attenuates progression linked to low protidemia, diastolic hypertension, proteinuria and high cholesterol.

Acidosis↗

[Fenofibrate increases blood creatinine, but does not change the glomerular filtration rate in patients with mild renal insufficiency].

Fenofibrate is a potent hypolipemic agent, widely used in patients with mild to severe renal failure in whom hyperlipoproteinemia is frequent. A moderate reversible increase in creatinine plasma levels has been reported with fenofibrate therapy; however, it is not known whether this increased creatininemia reflects a fenofibrate induced alteration of renal function or if fenofibrate interferes with creatinine tubular handling. We prospectively examined the effect of 2 weeks fenofibrate treatment (200 mg daily) on renal function in thirteen hyperlipidemic patients with normal renal function or mild to moderate renal failure (Creat Cl: 110 to 30 ml/min). This study confirms that fenofibrate therapy significantly increases creatininemia in patients with mild to moderate renal failure (147 +/- 12 versus 170 +/- 15 mmol/l; p = 0.014), but does not alter renal hemodynamic nor glomerular filtration rate as assessed by the stability of PAH (304 +/- 56 versus 311 +/- 49 ml/min; p = NS) and inulin clearances (51.7 +/- 6 versus 52.3 +/- 7 ml/min; p = NS). The increase in creatininemia is neither due to an inhibition of creatinine tubular excretion, since no change in creatinine clearance was observed (69 +/- 8 versus 68 +/- 8 ml/min; p = NS), but appears to be associated to a parallel increase in creatinine daily urinary excretion (13.7 +/- 5 versus 15.4 +/- 4 mmol; p = 0.03). In conclusion, fenofibrate therapy in renal patients does not worsen renal function, nor diminish the reliability of creatinine clearance for its follow-up in spite of a significant rise in creatininemia. The mechanism of the fenofibrate-induced increase in urinary creatinine excretion remains to be determined.

Aged↗