Adding the measurement of cystatin C to that of serum creatinine to determine the estimated glomerular filtration rate (eGFR) improves accuracy, but the effect on detection, staging, and risk classification of chronic kidney disease across diverse populations has not been determined.

A 65-year-old man presents with a rash of 2 days duration over the right forehead with vesicles and pustules, a few lesions on the right side and tip of the nose, and slight blurring in the right eye. The rash was preceded by tingling in the area and is now associated with aching pain. How should this patient be evaluated and treated?

A 45-year-old healthy man wishes to climb Mount Kilimanjaro (5895 m) in a 5-day period, starting at 1800 m. The results of a recent exercise stress test were normal; he runs 10 km 4 or 5 times per week and finished a marathon in less than 4 hours last year. He wants to know how he can prevent becoming ill at high altitude and whether training or sleeping under normobaric hypoxic conditions in the weeks before the ascent would be helpful. What would you advise?

Only 20 years after the discovery of the Hepatitis C Virus (HCV), a cure is now likely for most people affected by this chronic infection, which carries a substantial disease burden, not only in the United States but also worldwide. The recent approval of two direct-acting antiviral agents that specifically inhibit viral replication has dramatically increased the viral clearance rate, from less than 10% with the initial regimen of interferon monotherapy to more than 70% with current therapy. Moreover, many other drugs targeting viral or host factors are in development, and some will almost certainly be approved in the coming years. The questions of who should be treated and with what regimen will be increasingly complex to address and will require careful consideration. As therapy improves, systemwide identification and care of patients who need treatment will be the next challenge. Because most infected persons are unaware of their diagnosis, the Centers for Disease Control and Prevention recently recommended screening for HCV all persons born between 1945 and 1965., It is anticipated that in the course of such a screening process, a large number of persons will be found to be infected with the virus; whether it will be possible to treat all these people is unclear. This article reviews the current therapy for HCV infection and the landscape of drug development.