[Impact of left ventricular patterns and diastolic dysfunction on hemodialysis patients]. / Pattern cardiaci geometrici e disfunzione diastolica nel paziente uremico: quale l'impatto sul trattamento dialitico?

BACKGROUND: Left ventricular hypertrophy is the main manifestation of uraemic cardiomyopathy and predicts both cardiovascular events and death independently of conventional risk factors. Diastolic dysfunction is often associated with left ventricular hypertrophy, and accounts for up to 30% of heart failure. The aim of this study was to estimate the impact and the prevalence of left ventricular hypertrophy, its geometric models and diastolic dysfunction on haemodialysis patients, as well as the relationship with cardiac troponin, a specific marker for myocardial damage. METHODS: We enrolled in the study 31 patients (26 on haemodialysis, 5 on peritoneal dialysis) and 31 normal healthy subjects as the control group. Echocardiographic measurements were carried out according to the recommendations of the American Society of Echocardiography. Left ventricular mass was calculated according to the Devereux formula and indexed to height 2.7 We carried out Doppler echocardiography to study the diastolic function by measurements of isovolumic relaxation period (IVRT), E-wave deceleration time (DTE) and E/A ratio. We measured cardiac troponin using a third generation electrochemiluminescence immunoassay. We did the statistical analysis with the t test for comparison among groups, and we established correlations using the Pearson and Spearman correlation test. We considered values of p<0.05 to be statistically significant. RESULTS: Eccentric hypertrophy was the most frequent pattern (n=17; 55%), followed by normal cardiac geometry (n=7; 23%) and concentric hypertrophy (n=5; 16%). Only a minority of patients (n=2; 6%) showed concentric remodelling. Systolic dysfunction was present in 3 patients (EF<50%). Diastolic dysfunction was present in 24 out of 31 HD patients, that had abnormal relaxation pattern, characterised by prolonged IVRT, prolonged DTE and E/A ratio <1. Only one patient had restrictive filling pattern with reduced DTE and E/A ratio >2. Fourteen patients (45%) had E/A ratio < or =0.5, 10 patients (32%) had E/A ratio >0.5<1 and 7 patients (13%) had E/A ratio > or =1. DTE was prolonged in 14 patients (45%) and IVRT was prolonged in 6 patients (19%). The patients with E/A ratio < or =0.5 (n=14; 45%) suffered major hypotensive episodes during dialytic sessions compared to patients with E/A ratio >0.5, we found this difference to be statistically significant (p < 0.01). We observed the E/A ratio to be negatively correlated with age (r = -0.41; p=0.02) whereas DTE was positively correlated with posterior wall thickness (r =0.36; p= 0.05) and interventricular septum thickness (r =0.45; p=0.01). Cardiac troponin was positively correlated with age (r =0.50; p=0.00), left ventricular mass (r =0.41; p=0.02), posterior wall thickness (r =0.41; p=0.02) and interventricular septum thickness (r =0.39; p=0.03) but not with diastolic dysfunction parameters. Serum cardiac troponin was elevated (> or =0.10 micro g/L) in 12 patients (38.7%) and was associated with eccentric hypertrophy in all the cases. We detected no significant differences among groups with normal left ventricular geometry and left ventricular hypertrophy in the duration of the dialytic treatment, but we noted a statistically significant difference in relationship to age (p=0.03). CONCLUSIONS: Left ventricular hypertrophy is associated with diastolic dysfunction, both cause of hypotensive episodes during dialytic treatments and heart failure in patients with normal systolic function. The non invasive assessment of left ventricular diastolic function would represent an important advancement in the diagnosis and prevention of heart failure in haemodialysis patients.

[Myoglobinuric acute renal failure secondary to convulsion]. / Insufficienza renale acuta mioglobinurica secondaria a convulsioni.

Myoglobinuric acute renal failure secondary to convulsion.

[Polyomavirus BK nephropathy in renal transplant: 2 cases with different clinical expressions and review of the literature]. / Nefropatia da Poliomavirus BK nel trapianto renale: 2 casi con espressione clinica diversa e revisione della letteratura.

INTRODUCTION: Polyomavirus BK nephropathy is emerging as a significant cause of interstitial nephritis and allograft dysfunction (1-2). CASE REPORT: Two patients with renal transplants from cadaveric kidneys were treated with Tacrolimus plus Mycophenolate Mofetil (MMF) and Cyclosporine plus MMF, respectively. Their renal function gradually deteriorated eight to twelve months after the transplant. The renal biopsy of the first patient showed signs of significant interstitial tubulite, which necessitated the anti-rejection therapy with intravenous steroid pulses. After the pulses there was an additional dramatic increase in plasmatic creatinine, which suggested a revaluation of the kidney biopsy because of suspected Polyomavirus BK (BKV) nephropathy. In fact, after a more careful review, the suspicion of BKV infection was confirmed by the presence of intranuclear inclusions of tubular epithelium cells and marked denudation of the tubular basal membrane. The subsequent screening in both cases confirmed the presence of decoy cells in the urine, while the immunohistochemical analysis of the renal biopsy was strongly positive for the SV40 antigen. Our diagnosis was that of interstitial nephritis due to Polyomavirus BK that, in the first patient, was expressed by more aggressive clinical progress, probably due to enhanced immunosuppression from incorrect diagnosis of the interstitial rejection. The pre-transplant clinical outcome of the first patient was characterised by proteinuric nephropathy without any histological confirmation. Furthermore, we observed abundant pre-transplant residual diuresis and glucose intolerance. All these elements led us to hypothesise that native kidneys could have a fundamental role as viral reservoirs. CONCLUSION: Even though we reconfirm the decisive role of the immunosuppressive therapy and of the donor s kidney as the fundamental causes of Polyomavirus reactivation, we believe that it cannot be the result of a possible active role by the native kidney. In fact, as already noted, the SV40 genome is important in the pathogenesis of focal gomerulosclerosis. Furthermore, reports of polyoma nephropathy in not-yet-transplanted patients could accredit the role of the native kidneys as important viral reservoirs capable of inducing nephropathy in renal transplant patients.

[The measurement of vascular access recirculation and intra-access pressure in arteriovenous fistula monitoring in hemodialysis]. / La misura del ricircolo e delle pressioni statiche dell'accesso vascolare nel monitoraggio delle fistole artero-venose in emodialisi.

BACKGROUND: The main objective of monitoring vascular access flow in haemodialysis is maintenance of adequate access blood flow (Qac ) to prevent underdialysis and detection of haemodynamically significant stenosis prior to thrombosis. METHODS: Recirculation and intra-access pressure were measured to monitor arteriovenous fistulae in a group of haemodialysed patients, for a period of six months. Vascular access blood flow measurements were taken at the first (t0), second (t1) and sixth month (t2) by recirculation measurements using the thermodilution technique (BTM) consistent with Krivitsky's theory. Intra-access pressure measurements were made using the simplified Besarab's method. RESULTS: No statistically significant differences were noted in recirculation, vascular access blood flow, cardiac output and intra-access measurements during the three periods of the study. Vascular access blood flow was significantly and positively correlated with the arterial blood pressure measured at the same time, but not with the intra-access and venous pressures. Data indicate that mean Qac values = 300 mL/m. and induced recirculation values (Rp) = 45 and = 50 are correlated with angiographic findings of vascular access dysfunction. We observed that patients with mean Qac values between 300 and 650 mL/m had negative angiograms. CONCLUSIONS: We conclude that calculation of access flow by the double recirculation technique is a better and earlier predictor of access dysfunction whereas intra-access pressure measurements are not as useful for this purpose.

Renal tubular function by lithium clearance in liver cirrhosis.

Increased tubule sodium reabsorption has been largely suspected in liver cirrhosis (LC), however studies in humans have produced contrasting results. Therefore to ascertain the entity of renal sodium handling in LC this study was devised. A total of 13 patients with child A LC were studied along with 26 age-sex matched healthy controls (HC). Patients and controls were kept on daily Na-intake of 100 mmol for at last 1 week, by measuring glomerular filtration rate (GFR; inulin) and lithium clearance. We have calculated (1) C(Li); (2) the absolute reabsorption of isotonic fluid in the proximal tubule (APR) as GFR - C(LI); (3) the fractional proximal sodium reabsorption (FPRNa) as 1 - (C(Li)/GFR); (4) the absolute distal reabsorption of sodium (ADRNa) as (C(LI) - C(Na)) x P(Na;) and (5) the fractional distal sodium reabsorption (FDRNa) as (C(LI) - C(Na))/C(Li). GFR was significantly lower in LC (P<.001), C(Li) was significantly higher in LC than in HC (P<.001). APRNa and FPRNa were reduced in LC (P<.0001). ADRNa was higher in LC than in HC (P<.001). No difference was found for FDRNa. In conclusion, lithium clearance discloses an increase sodium reabsorption in distal tubule in humans with LC.

A contribution to the history of common salt.

Salt has influenced human nutrition, health, politics, taxation, economy, freight, transport, and commerce throughout the ages. All human activities have been influenced by salt including economy, religious beliefs and practices, art, literature, psychoanalysis, superstitions, and exorcism. Salt is recognized as a symbol for friendship, hospitality, chastity, alliance, table fellowship, fidelity, fertility, blessing, curse and endurance, etc. The Bible is the first book of salt and contains no fewer than 24 references to this substance. In the Gospels the parable of salt is a central one. Many many church fathers have written on salt a substance, which up to 1969 was a relevant element in the rite of Baptism. This paper reviews the importance of common salt for human life, and by drawing from various scientific and literary sources makes a special discussion of its various symbolisms.