Dialysis-associated pseudoporphyria successfully treated with vitamin D. Report of two cases.

Pseudoporphyria refers to a rare bullous dermatosis characterized by the clinical and histological features of porfiria cutanea tarda without abnormalities in porphyrin metabolism. The pathogenesis is heterogeneous and several exogenous factors may promote the bullous lesion formation, including medications, end stage renal disease, dialysis and tanning beds. Regarding treatment of this condition, in literature different therapy have been reported, such as glutathione and his precursor N-acetylcysteine, which presents anti-oxidant properties; however even more toxic drugs, such as chloroquine, are used. Moreover, in patients with drug-induced PP discontinuation of the offending agent, if possible, is a crucial aspect of the clinical management. We report two cases of dialysis patients presenting blisters on extremities, which healed with the avoidance of UV exposure and oral Vitamin D supplementation. Interestingly Vitamin D despite the lack of antioxidant properties led to a completely resolution of PP in both our patients within 30 days. A possible explanation of this finding is that Vitamin D, playing a key role in the regulation of serum Ca2+, can modulated cadherin-cadherin interactions and led to healing of pseudoporphyria bullous lesions. Finally we highlight the prominent role of UV-exposure in PP elicitation thus a good photoprotection is essential for all patients with pseudoporphyria.

Renoprotective effect of vasopressin v2 receptor antagonist tolvaptan in Dahl rats with end-stage heart failure.

Tolvaptan is a highly selective and orally effective arginine vasopressin V2 receptor antagonist, and is potentially useful for the treatment of heart failure (HF) patients. However, the renoprotective effect of long-term tolvaptan therapy and its underlying mechanisms remain unknown. We evaluated the effects of chronic treatment with tolvaptan on renal dysfunction, podocyte injury, inflammation, oxidative stress, Rho-kinase, epithelial-mesenchymal transition (EMT), and the extracellular signal-regulated protein kinase (ERK1/2) pathway in the renal cortex of Dahl salt-sensitive hypertensive (DS) rats with end-stage severe HF. DS and Dahl salt-resistant rats were fed a high-salt diet at 6 weeks of age. DS rats were treated with vehicle and tolvaptan (0.05% concentration in diet) from the age of 11 to 18 weeks. Vehicle-treated DS rats developed proteinuria, renal dysfunction, glomerulosclerosis, and interstitial fibrosis, which were ameliorated by tolvaptan without changing blood pressure. Decreased expression of nephrin and podocin and increased desmin-positive area in failing rats were restored by tolvaptan. Upregulation of NAD(P)H oxidase p22(phox), p47(phox), and gp91(phox), EMT markers such as transforming growth factor-ß1, vimentin, and fibronectin expression, and Rho-kinase and ERK1/2 phosphorylation in DS rats were significantly suppressed by tolvaptan. Tolvaptan administration resulted in significant inhibition of tumor necrosis factor-α and monocyte chemoattractant protein-1 expression, and nuclear factor-κB phosphorylation. We concluded that long-term tolvaptan therapy may improve renal dysfunction, glomerulosclerosis, podocyte injury, and inflammation associated with oxidative stress, as well as EMT, ERK, and the Rho-kinase pathway in the failing heart of DS rats. Thus, tolvaptan may be a therapeutic strategy for end-stage severe HF.

Arterial stiffness in patients with non-diabetic chronic kidney disease (CKD).

BACKGROUND: Patients with chronic kidney disease (CKD) have a high prevalence of cardiovascular disease (CVD). Arterial stiffness plays an important role in the pathogenesis of CVD; however, to date, there have been no reports of the assessment of arterial stiffness in patients at different stages of non-diabetic CKD. METHODS: We studied 50 patients with non-diabetic CKD (stages 1-5, 5D) receiving medical treatment at Tokyo Women's Medical University. Pulse wave velocity (PWV) was assessed using an applanation tonometer to determine arterial compliance. All current medications were recorded and biochemical parameters were analyzed. RESULTS: Non-diabetic CKD stage 5D patients had a higher PWV, and higher serum levels of C-reactive protein (CRP), Ca, P and intact parathyroid hormone (iPTH) than non-diabetic CKD stage 1-5 patients (p=0.03, p=0.009, p=0.006, p=0.00005, and p=0.002, respectably). As compared to non-diabetic CKD stage 1-2 patients, patients with non-diabetic CKD stage 3-5 were older, and had higher serum levels of P and iPTH and a higher PWV (p=0.0002, p=0.009, p=0.03, and p=0.004). Nephrosclerosis was associated with a higher PWV, higher serum levels of CRP, and a higher prevalence of CVD than patients with CKD of other origins. CONCLUSION: We showed a stepwise increase of arterial stiffness with increasing disease severity stage in patients with CKD not associated with diabetes mellitus. CKD caused by nephrosclerosis was found to be associated with increased arterial stiffness and to be a risk factor for CVD.

[The character and structure of infectious complications in patients with chronic renal failure, who received or did not receive replacement therapy (hemodialysis)].

The subjects of the study were 176 patients with chronic renal failure (CRF) (101 men; 75 women) aged 17 to 81. Stage I CRF was found in 46 patients, stage II CRF--in 69 patients, and stage III CRF--in 61 patients. Thirty-one patients with stage III CRF received program hemodialysis. Chronic glomerulonephritis was the main cause of CRF. With the progress of CRF, the frequency of infectious complications grew up to 2.2% in stage I, 7.2% in stage II, and 36.1% in stage III. The rate of infectious complications was higher in patients on program dialysis vs. patients without it: 51.6 and 20%, respectively. Pneumonia was the most frequent complication regardless CRF stage.

Risk factors of renal failure progression two years prior to dialysis.

AIM: The respective contribution of sex, type of nephropathy, degree of proteinuria, blood pressure, protein and sodium daily intakes, blood lipid profile, protidemia, hemoglobinemia, acidosis and CaPO4 product on the rate of renal failure progression is debated. PATIENTS AND METHODS: The link between these parameters and the decrease of creatinine clearance, deltaCcr (according to Cockroft) was assessed in uni- and multivariate analysis in a population of 49 patients (26 women; age 60+/-15 years, weight 79+/-15 kg) selected out of 173 presently treated hemodialysis patients on the basis of availability of a quarterly follow-up for 2 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. RESULTS: The 2-year deltaCcr was 14+/-14 ml/min. It was not different in men and women. This decrease in Ccr was neither significantly different in gomerular 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): deltaCcr = 15+/-14 vs 7+/-7 ml/min (p < 0.05) in spite of comparable blood pressure but with higher proteinuria. Linear regression of deltaCcr with the initial and 2-year averaged values of the quantitative parameters showed a significant positive link for both values with cholesterol, hemoglobine and proteinuria and a negative one with protidemia. A positive link was observed with the initial value of bicarbonate and the 2-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 2-year averaged value), diastolic BP (only for the 2-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 2 risk factors of progression (protidemia > or = 66 g/l, DBP > or = 90 mmHg, hemoglobinemia > 11 g/dl, proteinuria > or = 3 g/d, CT > 5 mmol/l) had a significantly greater decrease of Ccr than those with the 3 other combinations at the exception of the association of low protidemia with DBP. CONCLUSION: Diastolic hypertension and low protidemia are the 2 most important factors predicting progression of renal failure. A predictive synergy was furthermore pointed out between low protidemia or diastolic hypertension with proteinuria and cholesterol. On the contrary anemia attenuates progression linked to low protidemia, diastolic hypertension, proteinuria and high cholesterol.

How should we treat hypertensive women with cardiac and renal impairment?

Arterial hypertension is the most common chronic medical condition requiring office visits to physicians and is a major contributing factor to the development of myocardial infarction and stroke. Its importance as a cardiovascular risk factor is at least as significant in women as in men; however, the ever-growing literature on hypertension shows surprisingly little data concerning sex differences. Large clinical trials of antihypertensive treatment have not clearly demonstrated gender differences in blood pressure response and outcome, but the majority of patients in these trials were men. Even so, some evidence indicates that white women treated for hypertension obtain less benefit than men. The pathophysiology of hypertension in men and women is similar in many aspects, but important gender differences are now emerging. Studies designed to clarify these differences are required, as a better knowledge of the underlying mechanisms will allow for a more precise stratification of risk and a more accurate approach to both nonpharmacologic and pharmacologic treatment.

Hemosiderosis in a dialysis patient: treatment with hemofiltration and deferoxamine chelation therapy.

Although the highly permeable membranes utilized in hemofiltration are theoretically more permeable to deferoxamine-chelated iron than the standard cuprophan membranes used in conventional hemodialysis, no clinical data support this contention. Ours are the first published results of a preliminary short-term trial of combined therapy with deferoxamine and hemofiltration in a dialysis patient with hemosiderosis. An average of 15.3 mg of iron was mobilized with a 19.5-liter exchange over only 4 1/2 hours of postdilution hemofiltration. This compares favorable with previous reports in which 8 to 12 hours of dialysis were performed with Kiil dialyzers, and also with the 24-hour urinary excretion of chelated iron in iron-overloaded patients with normal renal function. We conclude that combined therapy with deferoxamine and hemofiltration offers promises as an effective means of iron mobilization in dialysis patients with hemosiderosis.

An accelerated hypertension with neither malignant nephrosclerosis nor elevation of plasma renin activity.

A case of accelerated hypertension, which was unique in a resistance to an angiotensin antagonist, and a lack of the elevation of plasma renin activity (PRA) is reported. Non-elevated PRA was coincided with non-malignant nephrosclerosis in renal histology. The acceleration was attributed to the neurological cause i.e., cerebral hemorrhage in the right hypothalamus which extended to the ventricle and subarachnoid space. The case therefore clinically seemed malignant-like, but it was not malignant hypertension in the sense of Volhard's classical definition. This does not conflict with the usefulness of the determination of PRA in the diagnosis of malignant hypertension with nephrosclerosis.