Most persons harbor staphylococci on the skin and in the nose or throat. Even if the skin can be cleared of staphylococci (eg, in eczema), reinfection by droplets will occur almost immediately. Because pathogenic organisms are commonly spread from one lesion (eg, a furuncle) to other areas of the skin by fingers and clothing, scrupulous local antisepsis is important to control recurrent furunculosis.

Serious multiple skin infections (acne, furunculosis) occur most often in adolescents. Similar skin infections occur in patients receiving prolonged courses of corticosteroids. In acne, lipases of staphylococci and corynebacteria liberate fatty acids from lipids and thus cause tissue irritation. Tetracyclines are used for long-term treatment.

Abscesses and other closed suppurating lesions are treated by drainage, which is essential, and antimicrobial therapy. Many antimicrobial drugs have some effect against staphylococci in vitro. However, it is difficult to eradicate pathogenic staphylococci from infected persons because the organisms rapidly develop resistance to many antimicrobial drugs, and the drugs cannot act in the central necrotic part of a suppurative lesion.

It may also be difficult to eradicate the S. aureus nasal carrier state. Some success has been reported with treatment of colonized individuals with intranasal mupirocin. Literature demonstrates success in reducing postsurgical wounds infections and prevention of bacteremia when treating identified hospitalized patients with 5 days of mupirocin with or without bathing using chlorhexidine, a topical antiseptic.

Acute hematogenous osteomyelitis responds well to antimicrobial drugs. In chronic and recurrent osteomyelitis, surgical drainage and removal of dead bone are accompanied by long-term administration of appropriate drugs, but eradication of the infecting staphylococci is difficult. Hyperbaric oxygen and the application of vascularized myocutaneous flaps have aided healing in chronic osteomyelitis.

Bacteremia, endocarditis, pneumonia, and other severe infections caused by S. aureus require prolonged intravenous therapy with a β-lactamase–resistant penicillin. Vancomycin is often reserved for use with nafcillin-resistant staphylococci. In recent years, an increase in MICs to vancomycin among many MRSA strains recovered from hospitalized patients has led physicians to seek alternative therapies. Alternative agents for the treatment of MRSA bacteremia and endocarditis include newer antimicrobials such as daptomycin, linezolid, and quinupristin–dalfopristin. Also, these agents may be bactericidal and offer alternatives when allergies preclude the use of other compounds or the patient’s infection appears to be failing clinically. However, the use of these agents should be discussed with infectious diseases physicians or pharmacists because the side effect profiles and pharmacokinetics are quite unique to each agent. A novel cephalosporin called ceftaroline, which has activity against MRSA and other Gram-positive and some Gram-negative bacteria, has been approved for the treatment of skin and soft tissue infections and community-acquired pneumonia. When combined with daptomycin, this drug can serve as a salvage therapy for bacteremia. If the infection is found to be caused by non–β lactamase-producing S. aureus, penicillin G is the drug of choice, but these S. aureus strains are rarely encountered.

S. epidermidis infections are difficult to cure because they occur in prosthetic devices where the bacteria can sequester themselves in a biofilm. S. epidermidis is more often resistant to antimicrobial drugs than is S. aureus; approximately 75% of S. epidermidis strains are nafcillin resistant. Several newer agents that have activity against CoNS and MSSA and MRSA have recently been FDA-cleared for treatment of skin and skin structure infections. These include dalbavancin, a long acting intravenous lipoglycopeptide; tedizolid phosphate, an intravenous and oral oxazolidinone, similar to linezolid; and oritavancin, a semisynthetic glycopeptide.

Because of the frequency of drug-resistant strains, mean ingful staphylococcal isolates should be tested for antimicrobial susceptibility to help in the choice of systemic drugs. Resistance to drugs of the erythromycin group tends to emerge so rapidly that these drugs should not be used singly for treatment of chronic infection. Drug resistance (to penicillins, tetracyclines, aminoglycosides, erythromycins, and so on) determined by plasmids can be transmitted among staphylococci by transduction and perhaps by conjugation.

Penicillin G–resistant S. aureus strains from clinical infections always produce penicillinase. They constitute more than 95% of S. aureus isolates in communities in the United States. They are often susceptible to β-lactamase resistant penicillins, cephalosporins, or vancomycin. Nafcillin resistance is independent of β-lactamase production, and its clinical incidence varies greatly in different countries and at different times. The selection pressure of β-lactamase resistant antimicrobial drugs may not be the sole determinant for resistance to these drugs: For example, in Denmark, nafcillin-resistant S. aureus comprised 40% of isolates in 1970 and only 10% in 1980 without notable changes in the use of nafcillin or similar drugs. In the United States, nafcillin resistant S. aureus accounted for only 0.1% of isolates in 1970 but in the 1990s constituted 20–30% of isolates from infections in some hospitals. Currently, about 60% of nosocomial S. aureus among intensive care patients in the United States are resistant to nafcillin. Fortunately, S. aureus strains of intermediate susceptibility to vancomycin have been relatively uncommon, and the isolation of vancomycin-resistant strains has been rare.

اخر الاخبار

اخبار العتبة العباسية المقدسة

فرقة العباس تنظم مجلس عزائها السنوي بذكرى شهادة النبي (صلى الله عليه وآله) في النجف

قسم الشؤون الفكرية وجامعة الكوفة يعقدان شراكة علمية لتدريب الطلبة على صيانة المخطوطات وحفظها

بالتزامن مع ذكرى شهادته.. قسم الشؤون الفكرية يصدر كتابًا عن النبي الأعظم (صلى الله عليه وآله)

بالصور.. جموع المؤمنين تحيي ذكرى شهادة الرسول الأكرم عند مرقد الإمام علي (صلوات الله عليهما)

المزيد

الآخبار الصحية

لون أسنانك يتحدث عن صحتك.. إليك ما يقول

عادة يومية بسيطة تخفض الكوليسترول وتحمي القلب

الزنجبيل.. دواء سحري لحماية القلب

المشروبات شديدة السخونة.. "خطر خفي" يهدد صحتك

المزيد

الآخبار التكنلوجية

كيف يمكن لعادات القيادة السيئة أن تؤثر على قيمة سيارتك

في طوفان الذكاء الاصطناعي.. نصائح لحجز "تذكرة النجاة"

هكذا يسرق "قراصنة الذكاء الاصطناعي" المليارات بطرق بسيطة

فيديو لانفجار كرة نارية في سماء اليابان.. ما تفسير ذلك؟

المزيد

مواضيع ذات صلة

Streptococcus pyogenes

Enzymes and Toxins of Staphylococci

Rocky Mountain Spotted Fever

Human Ehrlichiosis

Antimicrobial Susceptibility Testing and Therapy of Neisseria and Moraxella catarrhalis

Laboratory Diagnosis of Neisseria and Moraxella catarrhalis

Spirillum Minus

Streptobacillus moniliformis

Myositis and Myonecrosis

Necrotizing Fasciitis

Cellulitis

Laboratory Diagnosis of Francisella