Inflammation appears to have a key role in acute coronary syndromes. Myeloperoxidase, an enzyme that generates reactive oxygen species, is released from leukocytes on activation, and plasma levels of myeloperoxidase may serve as a marker of inflammation. In this study, plasma myeloperoxidase levels were found to be predictive of subsequent coronary events in patients with chest pain, even when patients were initially negative for troponin T.

Plasma myeloperoxidase levels may be of use in risk stratification among patients with suspected acute coronary syndromes.

Reactive oxygen species may have a role in the pathogenesis of atherosclerosis, and antioxidant enzymes that degrade these species may protect against atherosclerosis. In this study, the activity of one such enzyme, glutathione peroxidase 1, as measured in red cells, was found to be inversely correlated with the risk of subsequent coronary events.

The findings add evidence that reactive oxygen species may be involved in atherosclerosis and suggest the possibility that reducing reactive oxygen species may have therapeutic value.

Puberty does not occur in patients with idiopathic hypogonadotropic hypogonadism. This study investigated mutations in a candidate gene encoding a G protein–coupled receptor (GPR54). Affected members of an index pedigree were homozygous for an L148S mutation; an unrelated proband had two separate mutations, R331X and X399R. Isolated hypogonadotropic hypogonadism was also present in a knockout mouse that was engineered to lack this gene.

Mutations in the gene encoding GPR54 cause autosomal recessive idiopathic hypogonadotropic hypogonadism, suggesting that this receptor is essential for normal gonadotropin-releasing hormone–related physiology and for puberty.

In a large cohort study, 969 patients had an allergic reaction to a sulfonamide antibiotic, 96 (9.9 percent) of whom subsequently had a reaction after receiving a sulfonamide nonantibiotic. However, this rate was lower than that for reactions after receiving a penicillin.

These data suggest that there is no specific cross-reactivity to sulfonamide nonantibiotics in patients who have had an allergic reaction to a sulfonamide antibiotic. Instead, some patients may have a nonspecific predisposition to allergic reactions.

A reduction in historically high rates of hospital use was one goal of the Veterans Affairs (VA) system's 1995 introduction of primary care and capitated payment. This study of veterans with chronic disease showed that from 1994 through 1998, hospital use declined by 50 percent and urgent care visits fell by 35 percent. Mortality rates did not increase.

Major changes in the VA system in 1995 resulted in a marked decrease in hospital use without an increase in mortality among chronically ill veterans.

A 59-year-old man with bilateral olecranon-bursa tophi has frequent bouts of acute gouty arthritis, including three in the past year. Serum uric acid levels are consistently above 9 mg per deciliter. He is moderately obese and has mild, untreated hypertension. Allopurinol was discontinued after a maculopapular rash developed. How should this patient be treated?