Faculty Bibliography

Extracorporeal removal of drugs and other poisons is occasionally indicated in the management of intoxications. The available modalities include hemodialysis and several methods of continuous renal replacement therapy (CRRT), including continuous venovenous hemofiltration with or without dialysis augmenting drug removal. A growing literature promoting CRRT for extracorporeal removal has been published and is reviewed here. Estimates of clearance achieved by these techniques uniformly demonstrate that hemodialysis achieves higher clearances. CRRT may be appropriate for more hypotensive and unstable patients, though these might be the patients most in need of a more rapidly effective technique. For the most part, these case reports have not demonstrated that CRRT was necessary because of hemodynamic instability. Hemodialysis remains the first choice among modalities of extracorporeal removal with CRRT reserved for patients who truly cannot tolerate hemodialysis

Gout is a chronic disease in which excessively high levels of serum urate (hyperuricemia) result in tissue depositions of sodium urate crystals and intermittent inflammatory attacks. Patients who have gout frequently experience a range of comorbidities, which complicates management and affects long-term prognosis. We review some of the more important of these comorbidities and consider the extent to which gout or hyperuricemia may be either a consequence or a cause of these related conditions. In addition, we briefly consider several neurological conditions in which the presence of gout or a high serum urate level may be associated with less disease, rather than more

Chronic kidney disease (CKD) is a risk factor for poor outcomes in patients with coronary artery disease (CAD), but it is unknown whether CKD influences the efficacy of alternative CAD treatment strategies. Thus, we compared outcomes in stable CAD patients with and without CKD randomized to percutaneous coronary intervention (PCI) and optimal medical therapy (OMT) or OMT alone in a post hoc analysis of the 2,287 patient COURAGE study. At baseline, 320 patients (14%) had CKD defined as a glomerular filtration rate of <60 mL/min/1.73 m(2), as estimated by the abbreviated 4-variable Modification of Diet in Renal Disease equation. The patients with CKD were older (68 +/- 9 vs 61 +/- 10 years; p <0.001) and more often had diabetes mellitus (42% vs 33%; p = 0.002), hypertension (81% vs 65%; p <0.03), heart failure (13% vs 3.4%; p <001), and three-vessel CAD (37% vs 29%, p = 0.01). After adjustment for these differences, CKD remained an independent predictor of death or nonfatal myocardial infarction (hazard ratio 1.48, 95% confidence interval 1.15 to 1.90). PCI had no effect on these outcomes. Furthermore, at 36 months, a similar percentage of patients with CKD treated with OMT (70%) and PCI plus OMT (76%) were angina free compared to patients without CKD. In conclusion, CKD is an important determinant of clinical outcomes in patients with stable CAD, regardless of the treatment strategy. Although PCI did not reduce the risk of death or myocardial infarction when added to OMT for patients with CKD, it also was not associated with worse outcomes in this high-risk group

Pregabalin is prescribed for neuropathic pain. We report the first case of pregabalin toxicity in a hemodialysis patient and her successful treatment with hemodialysis. The patient was a 30-year-old woman on long-term hemodialysis therapy who experienced significant myoclonus of the arms and legs when her dose of pregabalin was mistakenly increased. The drug has 3 properties that contribute to making it amenable to removal by hemodialysis: relatively low molecular weight (159.23 Da), relatively low volume of distribution (0.5 L/kg), and not bound to plasma proteins. We achieved hemodialysis clearance of 88.8 mL/min, which was associated with resolution of symptoms immediately after hemodialysis

BACKGROUND: Individuals with advanced chronic kidney disease (CKD) and end-stage renal disease (ESRD) have high plasma total homocysteine (tHcy) levels, which may be a risk factor for cognitive impairment. Whether treatment with high-dose B vitamins to decrease high tHcy levels improves cognition in persons with kidney disease is unknown. STUDY DESIGN: Randomized controlled trial. SETTING & PARTICIPANTS: A substudy of 659 patients (mean age, 67.3 +/- 11.7 years) who participated in a randomized double-blind clinical trial 5 years in duration conducted in 36 US Department of Veterans Affairs medical centers of the effect on all-cause mortality of vitamin-induced lowering of plasma tHcy level. 236 (35.8%) were treated by using dialysis (ESRD) and 423 (64.2%) had a Cockcroft-Gault estimated creatinine clearance of 30 mL/min or less (advanced CKD). All had high tHcy levels (>/=15 mumol/L) at baseline. Cognitive assessments began during the follow-up period of the main trial 3 years after treatment began; participants subsequently were retested 1 year later to assess cognitive change. INTERVENTION: Daily high-dose B vitamin capsule (40 mg of folic acid, 100 mg of vitamin B(6), and 2 mg of vitamin B(12)) or placebo. OUTCOMES: Cognitive function at initial assessment and 1 year later. MEASUREMENTS: Telephone Interview of Cognitive Status-modified, supplemented with attention, working memory, and executive function tests. RESULTS: Initial cognitive function was impaired in approximately 19% of patients regardless of treatment assignment (vitamin or placebo) or kidney disease status (advanced CKD or ESRD). Treatment decreased tHcy levels by 26.7%. Unadjusted and adjusted analyses showed that treatment did not improve initial cognitive outcomes or affect subsequent cognitive status 1 year later. LIMITATIONS: Cognitive assessments began after treatment was initiated; cognitive assessment was limited. CONCLUSION: Treatment with high daily doses of B vitamins, which decreased tHcy levels, did not affect cognitive outcomes in patients with advanced CKD and ESRD

This issue provides a clinical overview of nephrolithiasis focusing on prevention, diagnosis, treatment, practice improvement, and patient information. Readers can complete the accompanying CME quiz for 1.5 credits. Only ACP members and individual subscribers can access the electronic features of In the Clinic. Non-subscribers who wish to access this issue of In the Clinic can elect 'Pay for View.' Subscribers can receive 1.5 category 1 CME credits by completing the CME quiz that accompanies this issue of In the Clinic. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including PIER (Physicians' Information and Education Resource) and MKSAP (Medical Knowledge and Self Assessment Program). Annals of Internal Medicine editors develop In the Clinic from these primary sources in collaboration with the ACP's Medical Education and Publishing division and with assistance of science writers and physician writers. Editorial consultants from PIER and MKSAP provide expert review of the content. Readers who are interested in these primary resources for more detail can consult www.acponline.org, http://pier.acponline.org, and other resources referenced within each issue of In the Clinic