The sirolimus-eluting stent has shown promise in the prevention of restenosis after balloon dilation of simple coronary lesions. This clinical trial compared the sirolimus-eluting stent with a standard stent in patients with complex coronary lesions. The sirolimus-eluting stent proved to be superior in the prevention of restenosis and neointimal hyperplasia.

Coronary stents coated with sirolimus have considerable promise in the treatment of simple and complex coronary stenoses.

In a study of more than 60,000 young adults, a history of infectious mononucleosis significantly increased the risk of Hodgkin's disease, but only disease in which the tumor tissue contained evidence of the Epstein–Barr virus (EBV).

This study makes a convincing connection among infectious mononucleosis, EBV, and the development of Hodgkin's disease. In absolute terms, the risk of Hodgkin's disease after infectious mononucleosis is low — about 1 case per 1000 persons.

Preexisting renal failure confers a risk of radiocontrast-agent–induced nephropathy after percutaneous coronary interventions. This study compared preemptive hemofiltration administered in an intensive care unit (ICU) with isotonic intravenous hydration given in a step-down unit for the prevention of contrast-agent–induced nephropathy in high-risk patients. A decrease in renal function occurred less frequently with hemofiltration (in 5 percent vs. 50 percent of patients; P<0.001). In-hospital and cumulative one-year mortality was lower in the hemofiltration group.

Periprocedural hemofiltration in an ICU appears to be effective in preventing the deterioration of renal function caused by the nephrotoxicity of contrast agents.

This controlled trial involving 39,836 children evaluated the efficacy of a 9-valent pneumococcal conjugate vaccine in South Africa. Vaccination decreased the frequency of invasive pneumococcal disease among both HIV-negative and HIV-positive children and reduced the number of first episodes of radiologically confirmed pneumonia.

This conjugate vaccine may be useful in countries where HIV infection is a major risk factor for pneumococcal disease. An additional benefit may be a reduction in the frequency of disease due to penicillin-resistant strains.

This study of the entire Medicare fee-for-service population documented substantial racial and geographic variation in the use of knee arthroplasty in the United States. Geographic variation explained part of the racial variation in national arthroplasty rates. However, geographic variation did not explain the significantly lower arthroplasty rates among black men than among non-Hispanic white men in nearly all geographic regions.

This study highlights the potential importance of examining geographic variation in efforts to understand and address racial disparities in the use of medical procedures.

Chronic constipation is a common condition that can be debilitating and difficult to treat. This review explains the physiologic processes involved in colonic transit and defecation. The evaluation of patients is summarized along with current strategies for clinical management.