Plasma Urate and Risk of a Hospital Stay with AKI: The Atherosclerosis Risk in Communities Study

Background and objectives

Higher urate levels are associated with higher risk of CKD, but the association between urate and AKI is less established. This study evaluated the risk of hospitalized AKI associated with urate concentrations in a large population-based cohort. To explore whether urate itself causes kidney injury, the study also evaluated the relationship between a genetic urate score and AKI.

Design, setting, participants, & measurements

A total of 11,011 participants from the Atherosclerosis Risk in Communities study were followed from 1996–1998 (baseline) to 2010. The association between baseline plasma urate and risk of hospitalized AKI, adjusted for known AKI risk factors, was determined using Cox regression. Interactions of urate with gout and CKD were tested. Mendelian randomization was performed using a published genetic urate score among the participants with genetic data (n=7553).

Results

During 12 years of follow-up, 823 participants were hospitalized with AKI. Overall, mean participant age was 63.3 years, mean eGFR was 86.3 ml/min per 1.73 m², and mean plasma urate was 5.6 mg/dl. In patients with plasma urate >5.0 mg/dl, there was a 16% higher risk of hospitalized AKI for each 1-mg/dl higher urate (adjusted hazard ratio, 1.16; 95% confidence interval, 1.10 to 1.23; P<0.001). When stratified by history of gout, the association between higher urate and AKI was significant only in participants without a history of gout (P for interaction=0.02). There was no interaction of CKD and urate with AKI, nor was there an association between genetic urate score and AKI.

Conclusions

Plasma urate >5.0 mg/dl was independently associated with risk of hospitalized AKI; however, Mendelian randomization did not provide evidence for a causal role of urate in AKI. Further research is needed to determine whether lowering plasma urate might reduce AKI risk.     

Low dose amiodarone and sotalol in the treatment of recurrent, symptomatic atrial fibrillation: a comparative, placebo controlled study

OBJECTIVE—To assess and compare the safety and efficacy of amiodarone and sotalol in the treatment of patients with recurrent symptomatic atrial fibrillation.
DESIGN—Prospective, randomised, single blind, placebo controlled study.
SETTING—Tertiary cardiac referral centre.
PATIENTS—186 consecutive patients (97 men, 89 women; mean (SD) age, 63 (10) years) with recurrent, symptomatic atrial fibrillation.
INTERVENTIONS—65 patients were randomised to amiodarone, 61 to sotalol, and 60 to placebo. Patients receiving amiodarone were maintained at a dose of 200 mg/day after a 30 day loading phase. The sotalol dose was 160-480 mg daily, as tolerated.
MAIN OUTCOME MEASURES—Recurrence of atrial fibrillation or side effects.
RESULTS—In the amiodarone group, 31 of the 65 patients developed atrial fibrillation after an average of six months, while 15 (11 in sinus rhythm and four in atrial fibrillation) experienced significant side effects after an average of 16 months. In the sotalol group, relapse to atrial fibrillation occurred in 47 of the 61 patients after an average of eight months; three experienced side effects during the titration phase. In the placebo group, 53 of the 60 patients developed atrial fibrillation after an average of four months (p < 0.001 for amiodarone and sotalol v placebo; p < 0.001 for amiodarone v sotalol).
CONCLUSIONS—Both amiodarone and sotalol can be used for the maintenance of normal sinus rhythm in patients with symptomatic atrial fibrillation. Amiodarone is more effective but causes more side effects.


Keywords: amiodarone; sotalol; atrial fibrillation     

Restenosis after elective coronary balloon angioplasty in patients with end stage renal disease: a case-control study using quantitative coronary angiography

Objective—To assess the rate of angiographic restenosis in patients with end stage renal disease after elective coronary angioplasty.
Design—A retrospective case-control study of 20 patients with end stage renal disease and 20 sex and age matched controls without renal disease, who had undergone primarily successful coronary angioplasty. Control coronary angiography was performed regardless of worsening or renewed incidence of anginal symptoms.
Main outcome measures—Group comparison of coronary morphology, as evaluated by quantitative coronary angiography, and of cardiovascular risk factors.
Results—The rate of angiographic restenosis was 60% in patients with renal disease and 35% in controls. In patients with end stage renal disease the following differences (mean (SD) were found versus controls: raised plasma fibrinogen (483 (101) v 326 (62) mg/dl, p < 0.001); raised plasma triglyceride (269 (163) v 207 (176) mg/dl, p < 0.01); smaller diameter of the coronary reference segment (2.59 (0.87) v 2.90 (0.55) mm, p < 0.10); smaller minimum luminal diameter of the dilated stenosis (0.77 (0.46) v 0.97 (0.27) mm, p < 0.05). Discriminant analysis showed that minimum luminal diameter before angioplasty (r = −0.79) and fibrinogen (r = +0.34) had the highest statistical association with restenosis.
Conclusions—The high rate of angiographic restenosis in patients with end stage renal disease seems to be related to the size of the vessel dilated and to an increased prothrombotic risk, as indicated by higher fibrinogen concentrations.

Keywords: renal disease;  coronary artery disease;  coronary angioplasty;  restenosis     

Gout is on the increase in New Zealand

OBJECTIVE—To determine the current prevalence of hyperuricaemia and gout in New Zealand Maori and Europeans for comparison with previous studies.
METHODS—342 Maori and 315 European men and women aged 15 years and older were studied by personal interview and a musculoskeletal system examination. The 1977 ARA criteria for gout in a survey setting were used and serum uric acid was determined by a uricase method. The data were compared with those of previous New Zealand studies.
RESULTS—Gout was significantly more common in Maori (6.4%) than Europeans (2.9%) (Δ = 3.6%, 95% confidence interval 0.4 to 6.8) and in Maori men (13.9%) than in European men (5.8%) (Δ = 8.1%, 95% CI 1.0 to 15.2). Hyperuricaemia was significantly more common in Maori men (27.1%) than in European men (9.4%) (Δ = 17.7%, 95% CI 8.3 to 27.1) and in Maori women (26.6%) than in European women (10.5%) (Δ = 16.1%, 95% CI 8.5 to 23.7). At least 14% of hyperuricaemic individuals were receiving diuretics, of whom 78% were women. Comparison with previous studies shows that the prevalence of gout has increased in both Maori and Europeans, particularly in men. In Maori men the prevalence of gout has risen from 4.5-10.4% previously to 13.9%, and in European men from 0.7%-2.0% previously to 5.8%. Clinical differences included a stronger family history, earlier age at onset, and a higher frequency of tophi and polyarticular gout in Maori than Europeans. Of those with gout, 62% of Maori and 63% of Europeans were hyperuricaemic on the day surveyed and six (19.4%) were on diuretics. Treatment of gout was inadequate in most cases.
CONCLUSIONS—Hyperuricaemia and gout remain common among Maori. Of concern is that the prevalence of gout appears to be on the increase, not only in Maori but also in Europeans in New Zealand.

     

Effects of febuxostat versus allopurinol and placebo in reducing serum urate in subjects with hyperuricemia and gout: A 28‐week,phase III,randomized, double‐blind,parallel‐group trial

Objective

To compare the urate‐lowering efficacy and safety of febuxostat, allopurinol, and placebo in a large group of subjects with hyperuricemia and gout, including persons with impaired renal function.

Methods

Subjects (n = 1,072) with hyperuricemia (serum urate level ≥8.0 mg/dl) and gout with normal or impaired (serum creatinine level >1.5 to ≤2.0 mg/dl) renal function were randomized to receive once‐daily febuxostat (80 mg, 120 mg, or 240 mg), allopurinol (300 or 100 mg, based on renal function), or placebo for 28 weeks.

Results

Significantly (P ≤ 0.05) higher percentages of subjects treated with febuxostat 80 mg (48%), 120 mg (65%), and 240 mg (69%) attained the primary end point of last 3 monthly serum urate levels <6.0 mg/dl compared with allopurinol (22%) and placebo (0%). A significantly (P < 0.05) higher percentage of subjects with impaired renal function treated with febuxostat 80 mg (4 [44%] of 9), 120 mg (5 [45%] of 11), and 240 mg (3 [60%] of 5) achieved the primary end point compared with those treated with 100 mg of allopurinol (0 [0%] of 10). Proportions of subjects experiencing any adverse event or serious adverse event were similar across groups, although diarrhea and dizziness were more frequent in the febuxostat 240 mg group. The primary reasons for withdrawal were similar across groups except for gout flares, which were more frequent with febuxostat than with allopurinol.

Conclusion

At all doses studied, febuxostat more effectively lowered and maintained serum urate levels <6.0 mg/dl than did allopurinol (300 or 100 mg) or placebo in subjects with hyperuricemia and gout, including those with mild to moderately impaired renal function.     

Biochemical effectiveness of allopurinol and allopurinol-probenecid in previously benzbromarone-treated gout patients

In 2003, the uricosuric drug benzbromarone was withdrawn from the market. The first alternative drug of choice was the xanthine oxidase inhibitor allopurinol. The purpose was to (1) investigate the efficacy of allopurinol (standard dosage) compared with previous treatment with benzbromarone; and (2) investigate the combination therapy allopurinol–probenecid as an effective alternative treatment compared with previous benzbromarone treatment. A prospective, open study was carried out in a cohort of 51 gout patients who discontinued benzbromarone therapy because of market withdrawal. Patients were given 200–300 mg allopurinol (stage 1). When allopurinol failed to attain the target serum urate (sUr) levels ≤0.30 mmol/l, probenecid 1,000 mg/day was added (stage 2). Treatment with benzbromarone monotherapy (range: 100–200 mg/day; mean 138 mg/day) resulted in 92% of patients reaching target levels sUr ≤ 0.30 mmol/l with a decrease of 61[11]% compared to baseline. In stage 1, 32 patients completed treatment with allopurinol monotherapy (range 200–300 mg/day; mean 256 mg/day), which resulted in 25% of patients attaining sUr target levels. Decrease in sUr levels was 36[11]%, which was significantly less compared to treatment with benzbromarone (p < 0.001). In stage 2, 14 patients received allopurinol–probenecid combination therapy, which resulted in 86% of patients attaining target sUr levels (after failure on allopurinol monotherapy), which was comparable to previous treatment with benzbromarone (p = 0.81). Decrease in sUr levels was 53[9]% (CI 95%: 48–58%), which was a non-significant difference compared to previous treatment with benzbromarone (p = 0.23). Benzbromarone is a very effective antihyperuricemic drug with 91% success in attainment of target sUr levels ≤0.30 mmol/l. Allopurinol 200–300 mg/day was shown to be a less potent alternative for most selected patients to attain target sUr levels (13% success). In patients failing on allopurinol monotherapy, the addition of probenecid proves to be an effective treatment strategy for attaining sUr target levels (86% success).     

Treatment of severe and difficult cases of systemic lupus erythematosus with tacrolimus. A report of three cases

OBJECTIVES—An analysis of the efficacy of tacrolimus treatment in three patients with difficult and severe systemic lupus erythematosus (SLE) whose active disease had been previously poorly controlled by cyclosporine and cyclophosphamide.
METHODS—A review of patient notes.
RESULTS—Two patients are well controlled after six and nine months of treatment with tacrolimus 0.06 mg/kg/day and 0.18 mg/kg/day. Previous persistent vasculitis had resolved and other features of active disease were controlled. The third patient's vasculitis had not improved significantly after two months of treatment and tacrolimus 0.17 mg/kg/day was discontinued because of nephrotoxicity.
CONCLUSION—Tacrolimus may be a useful additional immunosuppressive agent in some patients whose SLE is not well controlled by conventional treatments.

     

Effect of urate‐lowering therapy on the velocity of size reduction of tophi in chronic gout

Objective

The optimal serum urate levels necessary for elimination of tissue deposits of monosodium urate in patients with chronic gout is controversial. This observational, prospective study evaluates the relationship between serum urate levels during therapy and the velocity of reduction of tophi in patients with chronic tophaceous gout.

Method

Sixty‐three patients with crystal‐confirmed tophaceous gout were treated with allopurinol, benzbromarone, or combined therapy to achieve serum uric acid levels less than the threshold for saturation of urate in tissues. The tophi targeted for evaluation during followup were the largest in diameter found during physical examination.

Results

Patients taking benzbromarone alone or combined allopurinol and benzbromarone therapy achieved faster velocity of reduction of tophi than patients taking allopurinol alone. The velocity of tophi reduction was linearly related to the mean serum urate level during therapy. The lower the serum urate levels, the faster the velocity of tophi reduction.

Conclusion

Serum urate levels should be lowered enough to promote dissolution of urate deposits in patients with tophaceous gout. Allopurinol and benzbromarone are equally effective when optimal serum urate levels are achieved during therapy. Combined therapy may be useful in patients who do not show enough reduction in serum urate levels with single‐drug therapy.

     

An omega-3 polyunsaturated fatty acid concentrate administered for one year decreased triglycerides in simvastatin treated patients with coronary heart disease and persisting hypertriglyceridaemia

BACKGROUND—Omega-3 fatty acids, such as those present in fish oil, have been reported to prolong life in myocardial infarction survivors. These fatty acids can decrease serum triglyceride concentrations, but so far the doses used in trials examining their effects on coronary end points have had only minimal triglyceride lowering effects.
OBJECTIVE—To examine the triglyceride lowering effectiveness, safety, and tolerability of Omacor, a concentrate of omega-3, long chain, polyunsaturated fatty acids from fish oil (84% of the total as opposed to an average of 35% in fish oil) over one year in patients with established coronary heart disease (CHD) and persisting hypertriglyceridaemia, despite receiving simvastatin in doses similar to those employed in the Scandinavian simvastatin survival study.
SUBJECTS AND METHODS—59 patients with CHD, receiving simvastatin 10-40 mg daily with serum triglycerides > 2.3 mmol/l, were randomised to receive Omacor 2 g twice a day or placebo for 24 weeks in a double blind trial. Forty six patients accepted the offer of active treatment for a further 24 weeks in an open phase of the trial.
RESULTS—There was a sustained significant decrease in serum triglycerides by 20-30% (p < 0.005) and in very low density lipoprotein (VLDL) cholesterol by 30-40% (p < 0.005) in patients receiving active Omacor at three, six, and 12 months compared either to baseline or placebo. Omacor did not have any deleterious effect on low density or high density lipoprotein cholesterol or on biochemical and haematological safety tests. There was no adverse effect on glycaemic control in patients with diabetes, who showed a decrease in serum triglyceride, which was at least as great as in non-diabetic patients. One patient receiving placebo died of acute myocardial infarction. Three patients withdrew from the trial (two on placebo and one on active treatment). Omacor was generally well tolerated.
CONCLUSION—Omacor was found to be a safe and effective means of lowering serum triglycerides over one year in patients with CHD and combined hyperlipidaemia, whose triglycerides remained elevated despite simvastatin treatment.


Keywords: coronary heart disease; hypertriglyceridaemia; polyunsaturated fat; statin treatment     

A case-control investigation of the relation between hyperlipidaemia and calcific aortic valve stenosis

Objective—To investigate the relation of hyperlipidaemia to calcific aortic valve stenosis.
Design—A case-control study designed to detect a clinically relevant difference in the fasting plasma concentrations of total cholesterol between the groups at the 5% level with a power of 90%. Predefined subgroup analyses were based on presence of significant coronary disease and valve morphology (that is, bicuspid or tricuspid).
Setting—A district general hospital.
Subjects—20 patients with severe calcific aortic stenosis and 20 controls.
Results—Mean (SD) fasting plasma total cholesterol in patients with aortic stenosis was 0.79 (1.50) mmol/l greater than in the controls (p = 0.029). The magnitude of differences between patients with aortic stenosis and controls was similar whether the patients had coronary artery disease (0.78 (1.73) mmol/l) or not (0.80 (1.37) mmol/l). The presence of a stenosed tricuspid aortic valve was associated with a significant increase in plasma cholesterol (1.70 (0.87) mmol/l, p = 0.012). For bicuspid valves the degree of elevation of plasma cholesterol was less and not statistically significant.
Conclusions—Calcific aortic stenosis is associated with hypercholesterolaemia, especially when the valve is tricuspid. Further studies are necessary to confirm that the relation is causal. This finding may have implications for measures to prevent the most common cause of cardiac valve replacement in the developed world.

Keywords: calcific aortic stenosis;  hypercholesterolaemia;  hyperlipidaemia     

Response of the QT interval to mental and physical stress in types LQT1 and LQT2 of the long QT syndrome

OBJECTIVE—To study and compare the effects of mental and physical stress on long QT syndrome (LQTS) patients.
DESIGN—Case-control study.
MAIN OUTCOME MEASURES—QT intervals were measured from lead V3. Serum potassium and plasma catecholamine concentrations were also monitored.
PATIENTS—16 patients with type 1 LQTS (LQT1), 14 with type 2 LQTS (LQT2), both groups asymptomatic, and 14 healthy control subjects.
INTERVENTIONS—Three types of mental stress tests and a submaximal exercise stress test.
RESULTS—Heart rate responses to mental stress and exercise were similar in all groups. During mental stress, the mean QT interval shortened to a similar extent in controls (-29 ms), LQT1 patients (-34 ms), and LQT2 patients (-30 ms). During exercise, the corresponding QT adaptation to exercise stress was more pronounced (p < 0.01) in healthy controls (-47 ms) than in LQT1 (-38 ms) or LQT2 patients (-38 ms). During exercise changes in serum potassium concentrations were correlated to changes in QT intervals in controls, but not in LQTS patients. LQT1 and LQT2 patients did not differ in serum potassium, catecholamine or heart rate responses to mental or physical stress.
CONCLUSIONS—QT adaptation to mental and exercise stress in healthy people and in patients with LQTS is different. In healthy people QT adaptation is more sensitive to physical than to mental stress while no such diverging pattern was seen in asymptomatic LQTS patients.


Keywords: exercise; long QT syndrome; mental stress; potassium channel     

Women with gout: efficacy and safety of urate-lowering with febuxostat and allopurinol

Objective

To compare the characteristics of female versus male gout patients and assess urate‐lowering efficacy and safety of febuxostat or allopurinol treatment in women with gout.

Methods

This was a retrospective analysis of 4,101 hyperuricemic (serum urate [sUA] level ≥8.0 mg/dl) gout subjects enrolled in 3 phase III comparative trials and randomized to receive placebo, febuxostat (40 mg, 80 mg, 120 mg, or 240 mg daily), or allopurinol (100 mg, 200 mg, or 300 mg daily, based on renal function). Baseline demographics and characteristics were summarized and compared between female and male subjects. Urate‐lowering efficacy, which was defined as the proportion of subjects with sUA levels <6.0 mg/dl at final visit, was assessed for all subjects and, among women, according to baseline renal function.

Results

Female gout subjects (n = 226) were older with significantly higher rates of obesity and metabolic and cardiovascular comorbidities than their male counterparts. The percentage of female subjects with sUA levels <6.0 mg/dl at final visit was 0% in the placebo group, 54.3%, 85.1%, 81.0%, and 100.0% in the febuxostat 40 mg, 80 mg, 120 mg, and 240 mg groups, respectively, and 45.9% in the allopurinol group. Similar patterns of urate‐lowering efficacy rates were observed when stratified by renal function. Among all the female subjects, febuxostat 80 mg was significantly more efficacious than allopurinol (P < 0.001). Rates of adverse events (AEs) were low. The most frequently reported AEs were upper respiratory tract infections, musculoskeletal/connective tissue disorders, and diarrhea.

Conclusion

These data suggest that febuxostat 80 mg may be more efficacious than commonly prescribed doses of allopurinol in female gout subjects with high rates of comorbidities.     

Regulation of peripheral vascular tone in patients with heart failure: contribution of angiotensin II

Objective—To determine directly the contribution of angiotensin II to basal and sympathetically stimulated peripheral arteriolar tone in patients with heart failure.
Design—Parallel group comparison.
Subjects—Nine patients with New York Heart Association grade II-IV chronic heart failure, and age and sex matched controls.
Interventions—Forearm plethysmography, lower body negative pressure, local intra-arterial administration of losartan, angiotensin II, and noradrenaline, and estimation of plasma hormone concentrations.
Main outcome measures—Forearm blood flow responses, plasma hormone concentrations.
Results—Baseline blood pressure, heart rate, and forearm blood flow did not differ between patients and controls. In comparison with the non-infused forearm, losartan did not affect basal forearm blood flow (95% confidence interval −5.5% to +7.3%) or sympathetically stimulated vasoconstriction in controls. However, the mean (SEM) blood flow in patients increased by 13(5)% and 26(7)% in response to 30 and 90 µg/min of losartan respectively (p < 0.001). Lower body negative pressure caused a reduction in forearm blood flow of 20(5)% in controls (p = 0.008) and 13(5)% (p = 0.08) in patients (p = 0.007, controls v patients). Blood flow at 90 µg/min of losartan correlated with plasma angiotensin II concentration (r = 0.77; p = 0.03). Responses to angiotensin II and noradrenaline did not differ between patients and controls.
Conclusions—Losartan causes acute local peripheral arteriolar vasodilatation in patients with heart failure but not in healthy control subjects. Endogenous angiotensin II directly contributes to basal peripheral arteriolar tone in patients with heart failure but does not augment sympathetically stimulated peripheral vascular tone.

Keywords: angiotensin II;  heart failure;  peripheral vascular tone;  sympathetic nervous system     

Predicting Response or Non-response to Urate-Lowering Therapy in Patients with Gout

Purpose of Review

To review the extent of treatment success or failure with the xanthine oxidoreductase inhibitors allopurinol and febuxostat and indicate how the dosage of urate-lowering therapy (ULT) may be modified to increase the response in the majority of patients with gout.

Recent Findings

Gout flares are associated with serum concentrations of urate above 0.42 mmol/L (7 mg/dL). Achieving and maintaining serum urate below 0.36 mmol/L is considered an effective response to ULT. On an intention to treat basis, clinical trials indicate that allopurinol at daily doses of 100 to 300 mg decreases serum urate adequately in only about 40% of gout patients while febuxostat 80 mg daily reduces serum urate adequately in approximately 70% of gout patients. Higher doses of ULT may be required in patients receiving concomitant diuretics. The addition of a uricosuric agent to allopurinol and febuxostat therapy significantly increases the proportion of patients achieving adequate lowering of serum urate. Finally, carriers of a genetic variant of the transporter, ABCG2 (BCRP), have a decreased response to allopurinol.

Summary

Careful examination of medication adherence, titration of doses, and the addition of uricosuric agents increase the percentage of patients responding to allopurinol and febuxostat.

     

Lipophilic versus hydrophilic β1 blockers and the cardiac sympatho-vagal balance during stress and daily activity in patients after acute myocardial infarction

Objective—To compare the effects of a lipophilic and a hydrophilic β₁ blocker on cardiac sympatho-vagal balance during daytime activity and stress in patients four to six weeks after myocardial infarction.
Design—Randomised, double blind, crossover study comparing the effect of atenolol (50 mg once daily) with metoprolol CR (100 mg once daily) with treatment periods of four weeks.
Setting—Large teaching hospital.
Patients—50 patients (45 male, 5 female, age range 40 to 75 years), four to six weeks after an acute myocardial infarction.
Methods—At the end of each treatment period the 24 hour heart rate variability, heart rate variability power spectra during head up tilt and mental stress, baroreflex sensitivity, and exercise performance were evaluated.
Results—During daytime activity and during orthostatic and mental stress, both heart rate and the ratio between the low and high frequency spectral components of the heart rate variability were significantly lower with atenolol. Conversely, there was no difference between treatments in baroreflex sensitivity and resting plasma catecholamines. Exercise duration and peak oxygen consumption did not differ between treatments, but the heart rate during submaximal and peak exercise was significantly lower with atenolol.
Conclusions—At the doses used in this study, atenolol achieved greater β₁ adrenergic blockade than metoprolol CR and this was associated with significant inhibition of vagal withdrawal during stress. This suggests that peripheral blockade of β₁ adrenergic receptors may be more important than central blockade in preventing stress induced vagal withdrawal in patients after myocardial infarction.

Keywords: adrenergic receptors;  myocardial infarction;  stress;  baroreceptors     

A quantitative method for detecting deposits of amyloid A protein in aspirated fat tissue of patients with arthritis

OBJECTIVE—To describe a new, quantitative, and reproducible method for detecting deposits of amyloid A protein in aspirated fat tissue and to compare it with smears stained with Congo red.
METHODS—After extraction of at least 30 mg of abdominal fat tissue in guanidine, the amyloid A protein concentration was measured by a monoclonal antibody-based sandwich ELISA.
RESULTS—The concentrations in 24 patients with arthritis and AA amyloidosis (median 236, range 1.1-8530 ng/mg tissue) were higher (p<0.001) than in non-arthritic controls, uncomplicated rheumatoid arthritis, and other types of systemic amyloidosis (median 1.1, range 1.1-11.6 ng/mg tissue). Patients with extensive deposits, according to Congo red staining, had higher concentrations than patients with minute deposits.
CONCLUSION—This is a new, quantitative, and reproducible method for detecting deposits of amyloid A protein in aspirated fat tissue of patients with arthritis, even when minute deposits are present as detected in smears stained with Congo red.

Keywords: amyloid A protein; fat tissue; arthritis     

Can C reactive protein or troponins T and I predict outcome in patients with intractable unstable angina?

Objective—To determine whether a single blood test for the measurement of C reactive protein, or troponin I or T concentrations could be used to stratify patients with intractable unstable angina awaiting transfer for coronary angiography by correlating these values with coronary anatomy and transient myocardial ischaemia.
Design—Prospective study.
Setting—Tertiary cardiac unit.
Patients—All patients admitted to their local hospital with ischaemic chest pain, uncontrolled by medical treatment, in whom acute myocardial infarction had been excluded by serial measurement of creatine kinase and lack of Q waves on ECG.
Intervention—Coronary angiography and ST segment monitoring for 24 hours.
Main outcome measures—Concentrations of C reactive protein, troponins T and I, coronary anatomy, presence of transient myocardial ischaemia.
Results—Median C reactive protein, troponin I, and troponin T concentrations were 17.1 mg/dl (4.8 to 203.9), 0.05 µg/l (0 to 7.8), and 0.0 µg/l (0 to 2.51), respectively. Seven patients (10%) had normal coronaries and 14, 20, and 31 had one, two, or three vessel coronary disease, respectively. Nineteen (26%) had transient myocardial ischaemia, 33 (46%) had complex lesion morphology, and six (8%) had intracoronary thrombus. Of the three markers, troponin T alone was higher in patients with multivessel disease (p < 0.05) and in those with transient myocardial ischaemia (p < 0.05), but there was no significant relation between C reactive protein, troponin T or I and lesion morphology or thrombus.
Conclusions—In patients transferred to a tertiary centre with intractable chest pain, C reactive protein and troponin I are not predictive of transient myocardial ischaemia or lesion morphology, both of which are surrogate markers of outcome. Troponin T is, however, raised in patients with multivessel disease or transient myocardial ischaemia. These serum protein assays cannot be used to stratify the risk of patients with unstable angina who are awaiting transfer to the tertiary centre.

Keywords: C reactive protein;  troponin T;  troponin I;  unstable angina     

Ultrasonography shows disappearance of monosodium urate crystal deposition on hyaline cartilage after sustained normouricemia is achieved

This study aimed at determining whether lowering serum urate (SU) to less than 6 mg/dl in patients with gout affects ultrasonographic findings. Seven joints in five patients with monosodium urate (MSU) crystal proven gout and hyperuricemia were examined over time with serial ultrasonography. Four of the five patients were treated with urate lowering drugs (ULDs) (allopurinol, n = 3; probenecid, n = 1). One patient was treated with colchicine alone. Attention was given to changes in a hyperechoic, irregular coating of the hyaline cartilage in the examined joints (double contour sign or “urate icing”). This coating was considered to represent precipitate of MSU crystals. Index joints included metacarpophalangeal (MCP) joints (n = 2), knee joints (n = 3), and first metatarsophalangeal (MTP) joints (n = 2). The interval between baseline and follow-up images ranged from 7 to 18 months. Serial SU levels were obtained during the follow-up period. During the follow-up period, three patients treated with ULD (allopurinol, n = 2; probenecid, n = 1) achieved a SU level of <6 mg/dl. In two patients, SU levels remained above 6 mg/dl (treated with allopurinol, n = 1; treated with colchicine, n = 1). At baseline, the double contour sign was seen in all patients. In those patients who achieved SU levels of <6 ml/dl, this sign had disappeared at follow-up. Disappearance of the double contour sign was seen in two knee joints, two first MTP joints, and one MCP joint. In contrast, disappearance of the double contour sign was not seen in patients who maintained a SU level ≥7 mg/dl. In one patient treated with allopurinol, SU levels improved from 13 to 7 mg/dl during the follow-up period. Decrease, but not resolution of the hyperechoic coating was seen in this patient. In the patient treated with colchicine alone, SU levels remained >8 mg/dl, and no sonographic change was observed. In our patients, sonographic signs of deposition of MSU crystals on the surface of hyaline cartilage disappeared completely if sustained normouricemia was achieved. This is the first report showing that characteristic sonographic changes are influenced by ULDs once SU levels remain ≤6 mg/dl for 7 months or more. Sonographic changes of gout correlate with SU levels and may be a non-invasive means to track changes in the uric acid pool. Larger prospective studies are needed to further assess these potentially important findings.     

Changing the site of delivery of thrombolytic treatment for acute myocardial infarction from the coronary care unit to the emergency department greatly reduces door to needle time

OBJECTIVE—To quantify the change in door to needle time when delivery of thrombolytic treatment of acute myocardial infarction was changed from the coronary care unit to the emergency department.
DESIGN—A comparative observational study using prospectively collected data.
SETTING—Coronary care unit and emergency department of an Australian teaching hospital.
PARTICIPANTS—89 patients receiving thrombolysis in coronary care unit between June 1994 and January 1996, and 100 patients treated in the emergency department between April 1997 and May 1998.
INTERVENTIONS—From April 1997, by agreement between cardiology and emergency medicine, all patients with acute myocardial infarction receiving thrombolysis were treated by emergency physicians in the emergency department.
MAIN OUTCOME MEASURE—Door to needle time measured from time of arrival at the hospital to start of thrombolysis. Other outcomes included pain to needle time and mortality.
RESULTS—Median door to needle times were less for patients treated in the emergency department than in the coronary care unit (37 minutes, 95% confidence interval (CI) 33 to 44 v 80 minutes, 95% CI 70 to 89, respectively; p < 0.0001). Door to needle time was under 60 minutes in 83% of emergency department patients and 26% of coronary care unit patients (57% difference, 95% CI 45% to 69%; p < 0.0001). Median pain to needle time was less for emergency department patients than for coronary care unit patients (161 minutes, 95% CI 142 to 177 v 195 minutes, 95% CI 180 to 209; p = 0.004); times of less than 90 minutes occurred in 18% of emergency department patients v 1% of coronary care unit patients (17% difference, 95% CI 9% to 25%; p < 0.05). Overall mortality was similar in patients treated in the emergency department and the coronary care unit.
CONCLUSIONS—With a collaborative interdepartmental approach, thrombolytic treatment of acute myocardial infarction was more rapid in the emergency department, without compromising patient safety. This should improve the outcome in patients with infarcts treated with thrombolytic agents.


Keywords: thrombolysis; door to needle time; treatment delay; acute myocardial infarction     

Effect of urate-lowering therapy on the velocity of size reduction of tophi in chronic gout

OBJECTIVE: The optimal serum urate levels necessary for elimination of tissue deposits of monosodium urate in patients with chronic gout is controversial. This observational, prospective study evaluates the relationship between serum urate levels during therapy and the velocity of reduction of tophi in patients with chronic tophaceous gout. METHOD: Sixty-three patients with crystal-confirmed tophaceous gout were treated with allopurinol, benzbromarone, or combined therapy to achieve serum uric acid levels less than the threshold for saturation of urate in tissues. The tophi targeted for evaluation during followup were the largest in diameter found during physical examination. RESULTS: Patients taking benzbromarone alone or combined allopurinol and benzbromarone therapy achieved faster velocity of reduction of tophi than patients taking allopurinol alone. The velocity of tophi reduction was linearly related to the mean serum urate level during therapy. The lower the serum urate levels, the faster the velocity of tophi reduction. CONCLUSION: Serum urate levels should be lowered enough to promote dissolution of urate deposits in patients with tophaceous gout. Allopurinol and benzbromarone are equally effective when optimal serum urate levels are achieved during therapy. Combined therapy may be useful in patients who do not show enough reduction in serum urate levels with single-drug therapy.