Long-term use of low-molecular-weight heparin in hemodialysis patients: a 7-year experience.

BACKGROUND: Low-molecular-weight-heparin (LMWH) is not routinely used as anticoagulant in hemodialysis (HD). The ideal dose and the safety of long-term use are not known. METHODS: A prospective three-phase interventional study. Phase 1 involved dose titration, phase 2 safety and efficacy and phase 3 routine practice. RESULTS: During 7 years of the use of the LMWH enoxaparin (EN), 236 patients were treated with a total number of 60,987 HD sessions. The mean dose used during the titration phase was 0.43 +/- 0.16 mg/kg/session, which was subsequently reduced in phase 3 to 0.36 +/- 0.14 mg/kg/session. The long-term effects of EN on the platelet count and lipid profile were comparable to unfractionated heparin. CONCLUSION: The long-term use of LMWH (EN) with a reduced dose in HD is practical and safe.

Plasma N terminal pro-brain natriuretic peptide levels and its determinants in a multi-ethnic population.

This study documents the determinants and plasma levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) among hypertensive and normotensive subjects in a multi-ethnic population in the United Arab Emirates (UAE). We obtained demographic, anthropometric and clinical data, together with fasting NT-proBNP and biochemical indices from 128 hypertensive patients and 138 normotensive subjects matched for age, gender and ethnicity. Plasma NT-proBNP levels were significantly (P<0.001), and several-fold higher among hypertensives (median 5.92, inter quartile range (IQR): 1.79-18.48 pmol/l) than normotensives (median 1.78, IQR: 0.59-4.32 pmol/l) in the total study population, and the same was true for the ethnic groups separately. Similarly, plasma levels of glucose, blood urea nitrogen (BUN) and creatinine, but not insulin, were significantly (P<0.05) higher among hypertensives than normotensives. For all subjects combined, log NT-proBNP correlated positively and significantly with age (P<0.01), log glucose (P<0.05), systolic blood pressure (SBP, P<0.001), log BUN (P<0.001) and log creatinine (P<0.001). Multivariate regression analysis showed that NT-proBNP levels were independently and positively correlated with SBP, age, gender, log BUN, Emirati and South East Asian ethnic groups and inversely associated with current exercise. In conclusion, we found circulating levels of NT-proBNP to be significantly increased in hypertensive versus normotensive subjects in the UAE and independently related to SBP, age, gender, indices of renal function and possibly exercise. Our results further suggest a possible modulating effect of ethnicity on NT-proBNP levels.

An atypical course of Caroli's disease in a renal transplant patient--case report and review of the literature.

This is a rare case of Caroli's disease, diagnosed following renal transplantation in a patient with autosomal recessive polycystic kidneys. Despite advanced cystic transformation of the biliary tree with striking architectural changes, there was no evidence of portal hypertension or hepatic fibrosis. Moreover, the patient did not suffer a single episode of cholangitis, a most interesting feature of this case. Her clinical course was punctuated by repeated episodes of gastrointestinal and urinary tract infections with resistant organisms; but fortunately, she had no evidence of septicemia. Recurrent Salmonella gastroenteritis indicated a chronic carrier state with the dilated bile ducts possibly acting as a potential reservoir. This has significant implications considering the immune suppression associated with renal transplantation. In general, Caroli's disease is rare. Therefore, a high index of suspicion for the diagnosis of Caroli's disease is warranted especially in patients with ARPKD or ADPKD. Once confirmed, affected patients with end-stage renal disease such as our patient, should ideally undergo combined liver-kidney transplantation.

A case of primary diffuse tracheobronchial amyloidosis.

Tracheobronchial amyloidosis (TBA) is an uncommon localized form of amyloidosis with fewer than 150 reported cases in the literature. We report a case of primary diffuse tracheobronchial amyloidosis who presented with cough, wheezing, recurrent and progressive dyspnea as well as hemoptysis. Though there is no universally accepted treatment for the localized form, this patient was successfully treated with three sessions of bronchoscopic resection and adjuvant steroids. This report will review the various types of amyloidosis of the respiratory tract and their clinical features, in addition to discussing the different available treatment modalities for TBA.

Insulin blunts the natriuretic action of atrial natriuretic peptide in hypertension.

Hyperinsulinemia and insulin resistance are implicated in the etiology of hypertension, but the mechanisms involved have not been established. The objectives of this study were to determine whether untreated essential hypertensive patients are more sensitive to the antinatriuretic action of insulin and more resistant to the counteracting natriuretic effect of atrial natriuretic peptide in contrast to age- and sex-matched normotensive control subjects. Urinary sodium excretion was measured at baseline, during hyperinsulinemic euglycemic clamp, and during coadministration of insulin and atrial natriuretic peptide. Baseline urinary sodium excretion was not significantly different in the normotensive subjects (415 +/- 47 mumol/min, n = 12) and hypertensive patients (381 +/- 18 mumol/min, n = 10); with the institution of insulin infusion, there was a similar and significant decline from baseline (P < .001) to 289 +/- 35 mumol/min in normotensive subjects and 235 +/- 17 mumol/min in hypertensive patients. Atrial natriuretic peptide was able to oppose the antinatriuretic action of insulin in normotensive subjects, increasing urinary sodium excretion significantly to a mean level of 352 +/- 31 mumol/min (P < .05), which did not differ significantly from baseline. In the hypertensive group, atrial natriuretic peptide infusion had no effect on urinary sodium excretion (238 +/- 18 mumol/min), and the difference from baseline remained highly significant (P < .001). The hypertensive patients were significantly less insulin sensitive than their normotensive counterparts, as reflected by a lower glucose utilization rate and higher mean baseline plasma insulin level (P < .05 for each).(ABSTRACT TRUNCATED AT 250 WORDS)

Atrial natriuretic factor counteracts sodium-retaining actions of insulin in normal men.

It has been hypothesized that hyperinsulinemia is causally related to hypertension by its effect on renal sodium transport. To examine the relationship between the sodium-retaining actions of insulin and atrial natriuretic factor (ANF), 16 healthy subjects were studied on three occasions, approximately 1 wk apart, using standard clearance techniques to evaluate responses during the acute administration of insulin, low-dose ANF, or both. In study 1, the euglycemic clamp was used to increase plasma insulin 10-fold to an average of 320 +/- 14 (SE) pM. This maneuver produced an immediate and persistent fall in sodium excretion from 0.315 +/- 0.02 to 0.207 +/- 0.02 mmol/min (P < 0.001) independent of change in renal hemodynamics, lithium clearance, and catecholamines. The decline in sodium excretion was associated with a marked increase in fractional distal sodium reabsorption. Systolic and diastolic pressure did not change significantly. In study 2, low-dose ANF (0.3 pmol.kg-1.min-1) designed to raise plasma levels to twice baseline was administered simultaneously in a repeat of study 1. This maneuver abolished insulin-mediated sodium reabsorption. In study 3, low-dose ANF infusion alone produced no changes in tubular handling of sodium. Our findings indicate that insulin at levels found in hyperinsulinemic states caused sodium retention and that physiological increases in plasma ANF concentration abolished the sodium-retaining action of insulin. Our findings suggest that if hypertension is causally related to hyperinsulinemia, mechanisms besides renal sodium retention are responsible for the hypertensive properties of insulin.

Renal cell carcinoma presenting as nephrotic syndrome complicated by acute renal failure.

A case of minimal change nephropathy occurring in association with a renal cell carcinoma is presented and discussed. The case was unusual in that it was associated with acute renal failure necessitating hemodialysis for five weeks. The renal failure resolved but the nephrotic state persisted in spite of therapy with prednisone then cyclophosphamide. The literature on nephrotic syndrome causing acute renal failure and its association with solid tumors is briefly reviewed.