Unenhanced renal magnetic resonance angiography in patients with chronic kidney disease & suspected renovascular hypertension: Can it affect patient management?

BACKGROUND & OBJECTIVES: Renal artery stenosis (RAS) is an important cause of severe hypertension in patients with chronic kidney disease (CKD). It is important to detect RAS early as it can reverse hypertension and stop rapid deterioration of renal function. The potential drawbacks of various imaging modalities used to detect RAS including contrast-related adverse effects associated with diagnostic angiography have led to increasing interest in unenhanced magnetic resonance (MR) renal angiography. The aim of this study was to detect and grade RAS in patients with CKD and suspected renovascular hypertension using unenhanced MR angiography (UMRA) and to identify patients with significant RAS (>70%) who would subsequently require further investigation and revascularization. METHODS: Thirty five CKD patients with suspected RAS were subjected to UMRA using non-contrast MR angiography of ArTery and VEins 3D True fast imaging with steady state precession technique over a three year period. Patients with RAS >70 per cent on UMRA were subjected to digital subtraction angiography (DSA) with intervention if indicated. RESULTS: In all, 76 renal arteries were evaluated using UMRA in 35 patients, of which 18 arteries showed stenosis and 11 were haemodynamically significant (eight patients). Seven patients (10 renal arteries) underwent DSA. INTERPRETATION & CONCLUSIONS: An association between UMRA and DSA findings was obtained in six patients (nine renal arteries), and these patients were stented. Post-procedure follow up showed good improvement in blood pressure and renal function. UMRA was found to be a useful non-invasive imaging modality to detect RAS in CKD patients. It can identify patients who require further invasive angiography and revascularization.

A fatal case of prostatic abscess in a post-renal transplant recipient caused by Cladophialophora carrionii.

Fungal infection secondary to renal transplantation poses a significant threat to the life of the recipient with a high rate of morbidity and mortality. A high index of suspicion is necessary for early diagnosis of fungal infections in such patients. We herein report a fatal case of prostatic abscess in a post-renal transplant recipient.

Evaluation of a protocol for hypertonic saline administration in acute euvolemic symptomatic hyponatremia: A prospective observational trial.

CONTEXT: Acute symptomatic hyponatremia is a frequent yet poorly studied clinical problem. AIMS: To develop a non-weight based protocol for the treatment of acute symptomatic hyponatremia. SETTINGS AND DESIGN: Observational study in a Multi-disciplinary Intensive Care Unit of an urban tertiary care hospital. MATERIALS AND METHODS: Patients aged >18 years, admitted with euvolemic acute symptomatic severe hyponatremia (defined as serum sodium <120 meq/l with symptoms <24 hours), formed the study population. On confirmation of euvolemic status clinically and by laboratory investigations, patients were administered 100 ml of 3% NaCl over a period of 4 hours irrespective of the weight of the patient, followed by reassessment of serum Na at the end of 4 hours. The volume of hypertonic saline (in ml) required to increase serum Na by 8 meq/l was calculated using the formula: 100 × 8/increment in serum Na observed with 100 ml hypertonic saline. This volume was infused over the next 20 hours. To monitor renal water diuresis which may contribute to overcorrection, the urine specific gravity was monitored every 4 hours for sudden decrease of ≥ 0.010 from the baseline value. Measurement of serum Na was repeated if a fall in the urine specific gravity was observed and subsequently repeated every 4 hours. If no fall occurs in urine specific gravity, serum Na measurement was repeated at 12, 20 and at 24 hours (0 hour being the initiation of 100 ml hypertonic saline). The volume of infusate was adjusted if an excessive increment of serum Na (greater than 3 meq at 8 hours, 4 meq at 12 hours, 5 meq at 16 hours and 6 meq at 20 hours) was observed. Baseline characteristics were compared using chi-square test and Mann-Whitney U test. RESULTS: 58 patients formed the study cohort. The mean age was 58 years. The mean serum Na on admission was 114 meq/l. Administration of 100 ml hypertonic saline resulted in a mean increase in serum Na of 2 meq/l. The mean increase in serum Na over 24 hours was 9 meq/l and mean volume of hypertonic saline required for a serum Na increment of 8 meq/l was 600 ml. CONCLUSIONS: The non-weight based protocol with monitoring for water diuresis is reasonably an effective strategy in the treatment of acute euvolemic symptomatic hyponatremia.

Association of carnitine deficiency in Indian continuous ambulatory peritoneal dialysis patients with anemia, erythropoietin use, residual renal function, and diabetes mellitus.

OBJECTIVE: In the present study, we aimed to determine levels of free carnitine in hemodialysis (HD) and peritoneal dialysis (PD) patients in India and to correlate carnitine deficiency with various clinical parameters. METHODS: Patients on HD and PD at two tertiary care centers were selected for the study. Baseline data were obtained, and a free carnitine analysis was performed. Carnitine deficiency was defined as a free carnitine level of less than 40 micromol/L. RESULTS: The total number of study patients was 96 (77 on HD, 19 on PD). In the PD group, the mean age was 56 years, with 26.3% of the patients being vegan, 47.4% having diabetes, and 57.9% having a daily urine output of <500 mL. The mean carnitine level in that group was 38.9 micromol/L, and 68.4% of the patients had a carnitine deficiency. A Pearson correlation test failed to show any association of carnitine level with parameters such as anemia, use of erythropoietin, non-vegetarian diet, diabetes, and hypertension. In the HD group, the mean age was 45 years, with 22% of the patients being vegan, 23% having diabetes, and 45.5% having a daily urine output of <500 mL. The mean carnitine level in the group was 38.2 micromol/L, and 64.3% of the patients had a carnitine deficiency. Residual renal function and duration of dialysis were different in HD patients with and without carnitine deficiency. Carnitine levels in the HD group correlated positively and statistically significantly with the presence of diabetes and hypertension. CONCLUSION: This study is the first demonstration that Indian dialysis patients have carnitine deficiency.

cAMP inhibits inducible nitric oxide synthase expression and NF-kappaB-binding activity in cultured rat hepatocytes.

BACKGROUND: The inducible nitric oxide synthase (iNOS) is strongly expressed following inflammatory stimuli. Adenosine 3',5'-cyclic monophosphate (cAMP) increases iNOS expression and activity in a number of cell types but decreases cytokine-stimulated iNOS expression in hepatocytes. The mechanisms for this effect are unknown. METHODS: Rat hepatocytes were stimulated with cytokines to induce iNOS and cultured with cAMP agonists dibutyryl-cAMP (dbcAMP), 8-bromo-cAMP, and forskolin (FSK). Nitric oxide synthesis was assessed by supernatant nitrite levels and iNOS expression was measured by Northern and Western blot analyses. Nuclear factor kappaB binding was assessed by electromobility shift assay. RESULTS: Cyclic AMP dose dependently decreased NO synthesis in response to a combination of proinflammatory cytokines or interleukin-1beta (IL-1beta) alone. The adenylate cyclase inhibitor SQ 22,536 increased cytokine- or IL-1beta-stimulated NO synthesis. dbcAMP decreased iNOS mRNA expression and iNOS protein expression. Both dbcAMP and glucagon decreased iNOS promoter activity in rat hepatocytes transfected with the murine iNOS promoter and decreased DNA binding of the transcription factor NF-kappaB. CONCLUSION: These data suggest that cAMP is important in hepatocyte iNOS expression and agents that alter cAMP levels may profoundly alter the response of hepatocytes to inflammatory stimuli through effects onthe iNOS promoter region and NF-kappaB.