In a large, prospective study of children with lower respiratory tract illness, human metapneumovirus was identified in 49 of 248 specimens (20 percent) that were negative for other pathogenic viruses. The mean age of the infected children was 11.6 months, and 59 percent had symptoms of bronchiolitis. This virus was isolated only rarely from asymptomatic children.

Human metapneumovirus infection is a leading cause of respiratory tract infection in young children. Most of these illnesses occur from December through April.

The triggering receptor expressed on myeloid cells (TREM-1) is up-regulated in the presence of bacteria. The presence of soluble TREM-1 in bronchoalveolar-lavage fluid was the strongest independent predictor of pneumonia in 148 patients receiving mechanical ventilation who had possible bacterial or fungal pneumonia.

Further prospective evaluation will be required, but this rapid diagnostic test appears to have a high sensitivity and specificity for the diagnosis of pneumonia in patients receiving ventilation.

Strontium ranelate, an orally active drug, dissociates bone resorption (which is increased in osteoporosis) from bone formation (which is reduced but continues in osteoporosis). In this randomized, placebo-controlled study of 1649 postmenopausal women with osteoporosis and at least one previous vertebral fracture, fewer subjects receiving strontium ranelate had new vertebral fractures — a 41 percent risk reduction over a three-year period (relative risk, 0.59; 95 percent confidence interval, 0.48 to 0.73).

Strontium ranelate therapy seems to be safe and efficacious and results in an early and sustained reduction in the risk of vertebral fractures among postmenopausal women with osteoporosis.

Effusive–constrictive pericarditis is characterized by tense pericardial effusion in combination with a diseased visceral pericardium, causing cardiac constriction. Removal of pericardial fluid lowers intrapericardial pressure but not right atrial or left ventricular end-diastolic pressure.

Some cases may resolve spontaneously, but others require extensive pericardiectomy to treat cardiac constriction.

A 34-year-old man presented to the emergency department two weeks after returning from a trip to India, reporting a six-day history of anorexia, vomiting, malaise, fatigue, and dark urine. His alanine aminotransferase level was 7330 U per liter, the bilirubin level was 8 mg per deciliter, and a test of the serum for hepatitis A IgM antibodies was positive. He was admitted for observation and hydration. Should he have been vaccinated against hepatitis A before his departure, and should his household contacts receive vaccine?

Although some reports suggest that testosterone-replacement therapy may provide benefits for aging men, considerable controversy remains regarding indications for its use. Neither large-scale nor long-term studies have been initiated, in part because of theoretical concern regarding the risks associated with testosterone therapy, especially the possible stimulation of prostate cancer. This article discusses what is known (and not known) about the risks of testosterone-replacement therapy and provides recommendations for monitoring men who are receiving testosterone.