Items in AFP with MESH term: Staphylococcal Infections
ABSTRACT: Because of high incidence, morbidity, and antimicrobial resistance, Staphylococcus aureus infections are a growing concern for family physicians. Strains of S. aureus that are resistant to vancomycin are now recognized. Increasing incidence of unrecognized community-acquired methicillin-resistant S. aureus infections pose a high risk for morbidity and mortality. Although the incidence of complex S. aureus infections is rising, new antimicrobial agents, including daptomycin and linezolid, are available as treatment. S. aureus is a common pathogen in skin, soft-tissue, catheter-related, bone, joint, pulmonary, and central nervous system infections. S. aureus bacteremias are particularly problematic because of the high incidence of associated complicated infections, including infective endocarditis. Adherence to precautions recommended by the Centers for Disease Control and Prevention, especially handwashing, is suboptimal.
Management of Bacterial Endocarditis - Article
ABSTRACT: Most cases of bacterial endocarditis involve infection with viridans streptococci, enterococci, coagulase-positive staphylococci or coagulase-negative staphylococci. The choice of antibiotic therapy for bacterial endocarditis is determined by the identity and antibiotic susceptibility of the infecting organism, the type of cardiac valve involved (native or prosthetic) and characteristics of the patient, such as drug allergies. Antibiotic therapies discussed in this report are based on recommendations of the American Heart Association. Treatment with aqueous penicillin or ceftriaxone is effective for most infections caused by streptococci. A combination of penicillin or ampicillin with gentamicin is appropriate for endocarditis caused by enterococci that are not highly resistant to penicillin. Vancomycin should be substituted for penicillin when high-level resistance is present. Resistance of enterococci to multiple antibiotics including vancomycin is becoming an increasing problem. Native valve infection by methicillin-susceptible staphylococci is treated with nafcillin, oxacillin or cefazolin. The addition of gentamicin for the first three to five days may accelerate clearing of bacteremia. Infection of a prosthetic valve by a staphylococcal organism should be treated with three antibiotics: oral rifampin and gentamicin and either nafcillin, oxacillin, cefazolin or vancomycin, depending on susceptibility to methicillin. Vancomycin is substituted for penicillin in patients with a history of immediate-type hypersensitivity to penicillin.
Common Infections in Older Adults - Article
ABSTRACT: Infectious diseases account for one third of all deaths in people 65 years and older. Early detection is more difficult in the elderly because the typical signs and symptoms, such as fever and leukocytosis, are frequently absent. A change in mental status or decline in function may be the only presenting problem in an older patient with an infection. An estimated 90 percent of deaths resulting from pneumonia occur in people 65 years and older. Mortality resulting from influenza also occurs primarily in the elderly. Urinary tract infections are the most common cause of bacteremia in older adults. Asymptomatic bacteriuria occurs frequently in the elderly; however, antibiotic treatment does not appear to be efficacious. The recent rise of antibiotic-resistant bacteria (e.g., methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococcus) is a particular problem in the elderly because they are exposed to infections at higher rates in hospital and institutional settings. Treatment of colonization and active infection is problematic; strict adherence to hygiene practices is necessary to prevent the spread of resistant organisms.
Scalp Rash in a Newborn - Photo Quiz
ABSTRACT: The incidence of chronic osteomyelitis is increasing because of the prevalence of predisposing conditions such as diabetes mellitus and peripheral vascular disease. The increased availability of sensitive imaging tests, such as magnetic resonance imaging and bone scintigraphy, has improved diagnostic accuracy and the ability to characterize the infection. Plain radiography is a useful initial investigation to identify alternative diagnoses and potential complications. Direct sampling of the wound for culture and antimicrobial sensitivity is essential to target treatment. The increased incidence of methicillin-resistant Staphylococcus aureus osteomyelitis complicates antibiotic selection. Surgical debridement is usually necessary in chronic cases. The recurrence rate remains high despite surgical intervention and long-term antibiotic therapy. Acute hematogenous osteomyelitis in children typically can be treated with a four-week course of antibiotics. In adults, the duration of antibiotic treatment for chronic osteomyelitis is typically several weeks longer. In both situations, however, empiric antibiotic coverage for S. aureus is indicated.
ABSTRACT: Infectious endocarditis results from bacterial or fungal infection of the endocardial surface of the heart and is associated with significant morbidity and mortality. Risk factors include the presence of a prosthetic heart valve, structural or congenital heart disease, intravenous drug use, and a recent history of invasive procedures. Endocarditis should be suspected in patients with unexplained fevers, night sweats, or signs of systemic illness. Diagnosis is made using the Duke criteria, which include clinical, laboratory, and echocardiographic findings. Antibiotic treatment of infectious endocarditis depends on whether the involved valve is native or prosthetic, as well as the causative microorganism and its antibiotic susceptibilities. Common blood culture isolates include Staphylococcus aureus, viridans Streptococcus, enterococci, and coagulase-negative staphylococci. Valvular structural and functional integrity may be adversely affected in infectious endocarditis, and surgical consultation is warranted in patients with aggressive or persistent infections, emboli, and valvular compromise or rupture. After completion of antibiotic therapy, patients should be educated about the importance of daily dental hygiene, regular visits to the dentist, and the need for antibiotic prophylaxis before certain procedures.