Hyperuricemia, gout, and autosomal dominant polycystic kidney disease

The relationship between hyperuricemia, gout, and autosomal dominant polycystic kidney disease (ADPKD) is not widely recognized. In an attempt to further clarify this relationship, the authors have studied 17 patients with ADPKD, 9 controls, 9 patients with proven gout and chronic renal failure, 11 patients with gout and normal renal function, and 11 patients with chronic renal failure. The mean serum uric acid concentration was higher in patients with ADPKD as a group than in controls (8.0 +/- 1.7 mg/dl vs. 6.4 +/- 1.6 mg/dl, p less than .02). Clinical gout was identified in 24% of patients with ADPKD; none of the patients with chronic renal failure of other etiologies had gout. Fractional excretion of uric acid and the activity of the enzyme hypoxanthine guanine phosphoribosyl transferase (HGPRT) were not different among the groups studied. From this study the authors conclude that ADPKD should be included among those diseases associated with hyperuricemia and gout. A partial deficiency in HGPRT or abnormal renal handling of uric acid do not appear to be responsible for the increased incidence of gout in patients with ADPKD.     

Acute intermittent porphyria and chronic transaminase elevation

Acute intermittent porphyria is an autosomal dominant inherited disorder resulting from a deficiency of porphobilinogen deaminase activity, the third enzyme in the heme biosynthesis pathway. This disease is uncommon, although the prevalence is higher in asymptomatic heterozygotic carriers; however, this prevalence is difficult to establish because of the absence of symptoms. Although acute intermittent porphyria is a multisystemic disease, its most common form of presentation is abdominal pain and neurological or mental symptoms, which can sometimes be due to precipitating factors such as reduced energy intake, smoking, alcohol, some drugs, and stress. Diagnosis can be made by testing urinary porphobilinogen levels, with subsequent measurement of enzyme activity and DNA testing. Treatment is based on prevention of porphyria attacks by avoiding precipitating factors and early administration of intravenous glucose or hemin therapy. We present the case of a patient diagnosed with acute intermittent porphyria based on study of chronic mild alanine aminotransferase (ALT) elevation.     

Percutaneous coronary intervention versus coronary bypass graft surgery for patients with medically refractory myocardial ischemia and risk factors for adverse outcomes with bypass: The VA AWESOME multicenter registry: comparison with the randomized clinical trial.

OBJECTIVES: This study was designed to compare the three-year survival after percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery (CABG) in physician-directed and patient-choice registries with the Angina With Extremely Serious Operative Mortality Evaluation (AWESOME) randomized trial results. BACKGROUND: The AWESOME multicenter randomized trial and registry compared the long-term survival after PCI and CABG for the treatment of patients with medically refractory myocardial ischemia and at least one additional risk factor for adverse outcome with CABG. The randomized trial demonstrated comparable three-year survival. METHODS: Over a five-year period (1995 to 2000), 2,431 patients with medically refractory myocardial ischemia and at least one of five risk factors (prior heart surgery, myocardial infarction within seven days, left ventricular ejection fraction <0.35, age >70 years, intra-aortic balloon required to stabilize) were identified. By physician consensus, 1,650 patients formed a physician-directed registry assigned to CABG (692), PCI (651) or further medical therapy (307), and 781 were angiographically eligible for random allocation; 454 of these patients constitute the randomized trial, and the remaining 327 constitute a patient choice registry. Survival for CABG and PCI was compared using Kaplan-Meier curves and log-rank tests. RESULTS: The CABG and PCI 36-month survival rates for randomized patients were 79% and 80%, respectively. The CABG and PCI 36-month survival rates were both 76% for the physician-directed subgroup; comparable survival rates for the patient-choice subgroup were 80% and 89%, respectively. None of the global log-rank tests for survival demonstrated significant differences. CONCLUSIONS: Both registries support the randomized trial conclusion: PCI is an alternative to CABG for some medically refractory high-risk patients.     

Increased dopamine receptor binding in duodenal mucosa of duodenal ulcer patients

High-affinity and saturable membrane-bound dopamine binding sites have been characterized in rat and human gastrointestinal tissues. Although their role in experimental ulcerogenesis has been suggested, dopamine receptor activity in peptic ulcer disease has not been investigated. Radioligand binding studies were performed with mucosal tissue homogenates obtained from the antrum and duodenum of six male healthy volunteers and six male duodenal ulcer patients. The binding assay was performed in triplicate with a crude membrane fraction using [³H] dopamine as a ligand at a final concentration of 1 nM at 22 °C in the dark. Nonspecific binding (which usually comprised about 30% of total binding) was determined in the presence of a 100-fold excess of unlabeled dopamine. A significant (P<0.05) increase of [³H]dopamine binding was found in duodenal mucosa of duodenal ulcer patients. [³H]Dopamine binding in stomach (antrum) of normal and duodenal ulcer patients did not differ significantly. These findings provide preliminary evidence for a role of dopamine receptors in duodenal ulcer and suggest that biochemical abnormalities of gut dopamine function may be operative in the pathogenesis of peptic ulcer disease.     

Effect of antihypertensive combinations on arterial pressure,albuminuria, and glycemic control in patients with type II diabetic nephropathy: a randomized study

Type II diabetic patients with albuminuria are at high risk for cardiovascular complications; the intense antihypertensive treatment required often involves using drug combinations. The aim of the present study was to compare the effect of two different, renin-angiotensin blocking combinations, on blood pressure (BP), albuminuria and glycemic control. Its design was prospective, randomised, controlled, of parallel branches, and performed in one Endocrinology Department, in Spain. 77 type-II diabetic patients, with stable albuminuria (30-1,000 mg/day) were included. After a pre-inclusion time of 2 weeks, patients were randomised to verapamil SR/trandolapril 180/2 (VT) or losartan/hydrochlorothiazide (LH) 20/12.5 mg/day. Duration of treatment was 1 year. The evaluated parameters were changes in blood pressure, urinary albumin excretion for 24 hours, glycated hemoglobin and plasmatic urea. Overall BP significantly decreased from 161.6 +/- 18.7/83.6 +/- 10.2 mmHg to 137.2 +/- 15.7/70.9 +/- 8.3 mmHg (p < 0.0005). Values, by treatment, were: For VT, 164.3 +/- 18.5/87.2 +/- 10.7 mmHg at baseline and 135.0 +/- 15.1/71.3 +/- 8.4 mmHg at conclusion. For LH, 158.8 +/- 17.4/80.1 +/- 8.4 mmHg at baseline and 139.3 +/- 16.1/70.5 +/- 8.2 mmHg at conclusion. Albuminuria significantly decreased from 308.2 +/- 544.7 mg/day to 198.0 +/- 285.3 mg/day. Both parameters showed no significant difference between treatments. Glycated hemoglobin decreased from 7.59 +/- 1.3% to 7.14 +/- 1.2% in the VT group, and from 7.96 +/- 1.29% to 7.84 +/- 1.62% in the LH group (ANOVA, p = 0.022). Changes adjusted from baseline values showed a trend to the difference between both treatments (p = 0.092). Plasmatic urea increased from 39.8 +/- 12.7 to 40.5 +/- 11.1 mg/dL in the TV group and from 43.4 +/- 12.0 mg/dL to 52.4 +/- 19.4 mg/dL in the LH group (ANOVA, p = 0.028). In conclusion, both treatments reduce blood pressure and albuminuria in a similar way in type II diabetic patients. The verapamil/trandolapril combination contributes to a better carbohydrate metabolism than losartan/hydroclorothiazide.     

Thrombotic microangiopathy as a cause of dilated cardiomyopathy in HIV-infected patients

Thrombotic microangiopathy is a rare cause of dilated cardiomyopathy. Both entities have been described separately in the setting of HIV infection. However, no patient with these 2 conditions has been reported to date. We report here 2 HIV-infected patients with dilated cardiomyopathy seemingly caused by thrombotic microangiopathy.