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This Week in JAMA
JAMA. 2005;293:1949.
Genetics of Colorectal Cancer
Identification and follow-up of patients at risk of familial colorectal cancer (CRC) are the subject of 2 articles in this issue of JAMA. First, Lindor and colleagues (SEE ARTICLE) examined cancer incidence in persons with a family pedigree that suggests hereditary nonpolyposis colorectal cancer (HNPCC) but who lacked the characteristic DNA mismatch repair gene defect. They found that families without the DNA defect had a lower CRC risk, were diagnosed at a later age, and had a lower incidence of other malignancies associated with HNPCC than did families with the defect. In the second article, Piñol and colleagues (SEE ARTICLE) assessed the accuracy of the revised Bethesda guidelines for identifying individuals at risk of HNPCC. They found that microsatellite instability testing and immunostaining are equivalent and effective in selecting patients for further genetic testing. In an editorial, Vasen and Boland (SEE ARTICLE) discuss the utility and application of molecular diagnostic tools for patients with CRC and their families.
Patient Requests for Advertised Antidepressants
Direct-to-consumer advertising (DTCA) of prescription medications is controversial, with claims that it may cause overuse of unnecessary medication or prevent underuse of effective medication. In a randomized trial using standardized patients exhibiting symptoms of major depression or adjustment disorder, Kravitz and colleagues (SEE ARTICLE) assessed the effects of patients’ DTCA-related requests on primary care physicians’ initial treatment decisions. For patients exhibiting signs of major depression, antidepressant prescribing rates were 76% for patients who made a general request for treatment, 53% for those who had asked for a specific brand, and 31% for patients who made no request. For patients exhibiting signs of adjustment disorder, antidepressant prescribing rates were 39% for those making a general request, 55% for those asking for a specific brand, and 10% for those who made no request. In an editorial, Hollon (SEE ARTICLE) describes the relationship of DTCA to prescribing decisions and the need for evidence-based and regulated advertisements.
Neuroprotective and Antiviral Effects of Minocycline
Current antiretroviral drugs suppress human immunodeficiency virus (HIV) replication in peripheral blood, but effects on HIV sequestered in the central nervous system (CNS) are significantly less. With evidence that minocycline has anti-inflammatory and neuroprotective effects in animal models of disease, Zink and colleagues investigated whether it could prevent encephalitis and neurodegeneration in pigtailed macaques infected with simian immunodeficiency virus (SIV). In addition, they assessed the effect of minocycline on HIV and SIV replication in cultured lymphocytes and macrophages. They found that SIV-infected macaques treated with minocycline had less severe encephalitis and less virus replication in the CNS than did those not treated with minocycline and that minocycline suppressed HIV and SIV replication in cell cultures.
(SEE ARTICLE)
Validity of CT to Detect Pulmonary Embolism
Computed tomography (CT) is increasingly used to assess patients with suspected pulmonary embolism, but the validity of a negative CT and the safety of withholding anticoagulant therapy are uncertain. Quiroz and colleagues analyzed pooled data from 3500 patients in studies that used CT to rule out the diagnosis of acute pulmonary embolism to calculate a negative likelihood ratio of venous thromboembolism after a negative chest CT. They found the negative predictive value for CT was comparable with pulmonary angiography and found no evidence of adverse clinical outcomes when anticoagulant therapy was withheld.
(SEE ARTICLE)
Medical News & Perspectives
Studies of the X chromosome reveal an unsuspected degree of genetic variation between the sexes and among women that may help explain some medically important differences between men and women.
(SEE ARTICLE)
CLINICIAN’S CORNER
Vaginal Prolapse
Clinical Crossroads
Mrs H is a married and sexually active 80-year-old woman who reported recent symptoms of tissue coming out of her vagina. Cundiff discusses the pathophysiology, epidemiology, and assessment of vaginal prolapse and provides options for treatment.
(SEE ARTICLE)
JAMA Patient Page
For your patients: Information about uterine prolapse.
(SEE ARTICLE)
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