Prolonged afebrile nonproductive cough illnesses in American soldiers in Korea: a serological search for causation.

A serological study was undertaken to investigate infections in active-duty United States soldiers with illnesses characterized by prolonged, afebrile, nonproductive coughs. Fifty-four soldiers were enrolled with such illness of >/=2 weeks' duration (case patients) along with 55 well soldiers (control subjects). Serum samples were tested for IgG and IgA antibody to 3 Bordetella pertussis antigens, pertussis agglutinins, IgM antibodies to Mycoplasma pneumoniae, IgM and IgG antibodies to Chlamydia pneumoniae, and IgM antibody to adenoviruses. Forty-six case patients (85%) had evidence of recent infection with Bordetella species, M. pneumoniae, or C. pneumoniae, and many had evidence of mixed infections; there were 27 Bordetella species, 20 C. pneumoniae, and 33 M. pneumoniae recent infections. Fifteen case patients had high titers of IgG or IgA to B. pertussis filamentous hemagglutinin without high titers of antibodies to other B. pertussis antigens, which suggested the presence of cross-reacting antibodies to M. pneumoniae and perhaps C. pneumoniae or unidentified infectious agent or agents. Since illnesses due to Bordetella species, M. pneumoniae, and C. pneumoniae can all be treated with macrolide antibiotics and B. pertussis illness can be prevented by immunization, and since military readiness was affected in 63% of the cases, it seems important to conduct further studies in military populations.     

Role of thrombotic and fibrinolytic factors in acute coronary syndromes

There is a growing body of literature concerning the contribution of hemostatic factors to the development of cardiovascular disease. The mechanisms of the coagulation/fibrinolytic system are complicated and one factor is intimately interrelated with another; thus the contribution of each factor cannot be clearly understood, unless hemostatic factors are considered in accordance with endothelial function and vessel morphology. Although there are many clinical studies about the correlation between hemostatic factors and cardiovascular risk, the results are inconsistent and conflicting at times. Fibrinogen and D-dimer are associated with atherosclerosis or coronary events across multiple studies, even after multivariate adjustment. But the hemostatic factors are intimately correlated, so it can be said that focusing on one to the exclusion of others is inappropriate. The clinical trials with statins or angiotensin converting enzyme inhibitors have shown favorable effects on the prognosis of cardiovascular disease. The study of hemostatic factors in relation to these drugs has provided insights into understanding how these drugs produce beneficial effects.     

Mechanisms of Cardiovascular Disease in the Setting of HIV Infection

Although the initial reports of increased cardiovascular (CV) disease in the setting of advanced AIDS were reported approximately 30 years ago, advances in antiretroviral therapy and immediate initiation of therapy on diagnosis have transformed what was once a deadly infectious disease into a chronic health condition. Accordingly, the types of CV diseases occurring in HIV have shifted from pericardial effusions and dilated cardiomyopathy to atherosclerosis and heart failure. The underlying pathophysiology of HIV-associated CV disease remains poorly understood, partly because of the rapidly evolving nature of HIV treatment and because clinical endpoints take many years to develop. The gut plays an important role in the early pathogenesis of HIV infection as HIV preferentially infects CD4+ T cells, 80% of which are located in gut mucosa. The loss of these T cells damages gut mucosa resulting in increased gut permeability and microbial translocation, which incites chronic inflammation and immune activation. Antiretroviral therapy does not cure HIV infection and immune abnormalities persist. These abnormalities correlate with mortality and CV events. The effects of antiretroviral therapy on CV risk are complex; treatment reduces inflammation and other markers of CV risk but induces lipid abnormalities, most commonly hypertriglyceridemia. On a molecular level, monocytes/macrophages, platelet reactivity, and immune cell activation, which play a role in the general population, may be heightened in the setting of HIV and contribute to HIV-associated atherosclerosis. Chronic inflammation represents an inviting therapeutic target in HIV, as it does in uninfected persons with atherosclerosis.     

Cardiac arrest in patients who smoke crack cocaine

The aim of the study is to determine the clinical features and outcomes of cocaine users admitted to the hospital after cardiac arrest and compare them with nonusers. Cocaine is associated with cardiovascular complications, including ventricular arrhythmias; however, resuscitated cardiac arrest in relation to cocaine use is not a well-defined clinical entity. We reviewed available hospital charts at San Francisco General Hospital with the International Classification of Diseases, Ninth Revision diagnosis of cardiac arrest and cocaine use from 1994 to 2006. Clinical features and outcomes of cocaine users were compared with those of randomly selected control patients and age-matched controls with resuscitated cardiac arrest without cocaine use. We identified 22 patients with resuscitated cardiac arrest in the setting of cocaine use. Their average age was 42 +/- 10 years, >20 years younger than nonusers (68 +/- 16 years, p <0.01). After cardiac arrest, 12 of 22 patients (55%) who used cocaine had complete neurologic recovery in contrast to only 3 of 20 unmatched controls (15%, p <0.01) and 7 of 41 age-matched controls (17%, p <0.01). Only 10 of 22 cocaine users (46%) died compared with 15 of 20 unmatched controls (75%, p = 0.05) and 32 of 41 age-matched controls (78%, p <0.01). In a combined analysis of all patients, cocaine use was the only significant predictor of neurologic recovery (p <0.01) and survival (p <0.01). In conclusion, cocaine use is associated with cardiac arrest. In patients with cardiac arrest, cocaine users are younger than nonusers and more likely to survive with neurologic recovery, even compared with age-matched controls with cardiac arrest.