Is there any association between contrast-induced nephropathy and serum uric acid levels?

Introduction: During the recent years, several studies have investigated that hyperuricemia is associated with greater incidence of contrast induced nephropathy (CIN). Most of them are in acute conditions like primary percutaneous coronary interventions. This study aimed to assess the relationship between high serum uric acid and incidence of acute kidney injury in patients undergoing elective angiography and angioplasty. Methods: This prospective study was conducted on 211 patients who were admitted to hospital for elective coronary angiography or angioplasty. The researchers measured serum creatinine and uric acid on admission and repeated creatinine measurement in 48 hours and seven days after the procedure. According to serum uric acid, the patients were divided into two groups; group 1 with normal uric acid and group 2 with hyperuricemia which was defined as uric acid more than 6 mg/dL in women and 7 mg/dL in men. CIN is defined as an increased creatinine level of more than 0.5 mg/dL or 25% from the baseline in 48 hours after the intervention. Results: In total, 211 patients with mean age of 60.58 years were enrolled in the study. Of these, 87 (41.2%) patients were in the high uric acid group and 124 (58.8%) were in the normal uric acid group. CIN was occurred in 16 patients (7.5%). Seven out of 16 (8.04%) were in the high uric acid and nine (7.2%) were in the normal uric acid group. There were no significant differences between the two groups (P =0.831). Conclusion: The frequency of CIN development was not different in the patients with hyperuricemia

Frequency of renal artery stenosis and associated factors in patients undergoing coronary angiography

Background: Coronary artery disease (CAD) is the first cause of mortality in developed and developing countries, including Iran. Identifying high-risk patients can save many from morbidity and mortality. Renal artery stenosis (RAS) seems to be equivalent to CAD in patients with cardiovascular risk. Objectives: The present study aimed to determine the prevalence, severity, and extent of RAS and its predictors in patients with confirmed CAD on coronary angiography. Patients and Methods: All patients suspected of ischemic heart disease (IHD), who underwent diagnostic coronary angiography at Heshmat heart hospital, Iran were recruited (May 2015 to June 2016). Patients with confirmed CAD underwent non-selective renal angiography, which was categorized as mild, moderate or severe based on luminal diameter narrowing more than normal >0% to 50%, between 50%-70% and more than 70%, respectively. Results: Of 233 patients, RAS was observed in 123 (53%). Around 20% were mild, 10% were moderate and 23% were severe. Additionally, RAS in 37% was unilateral and in 16% were bilateral. Besides,19%, 25% and 56% of patients had atherosclerosis in one, two and three vessels, respectively. There was no correlation between the CAD severity and severity of RAS (P=0.807). Conclusions: Higher prevalence of RAS in patients with hyperlipidemia (60% vs. 40%) was detected. Its association with variables affecting CAD indicates that RAS can be a predictor of CAD. Therefore, simultaneous assessment of RAS in coronary angiography can be a good screening method for CAD beside earlier diagnosis of kidney disease