Tags: Nafcillin

Streptococcal Toxic Shock Syndrome

In the late 1980s, invasive GAS infections occurred in North America and Europe in previously healthy individuals of all ages. This illness is associated with bacteremia, deep soft-tissue infection, shock, multi-organ failure, and death in 30% of cases. StrepTSS occurs sporadically, although minor epidemics have been reported. Most patients present with a viral-like prodrome, history of minor trauma, recent surgery, or varicella infection. The prodrome may be caused by a viral illness that predisposed to strepTSS, or these vague early symptoms may be related to the evolving infection. In cases associated with necrotizing fasciitis, the infection may begin deep in the soft tissue at a site of minor trauma that frequently …

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Staphylococci

STAPHYLOCOCCUS AUREUS Essentials of Diagnosis • Large gram-positive cocci (0.7-1.5 um in size). • Colonies surrounded by zone of hemolysis on blood agar. • Colonies pigmented pale yellow to deep orange macroscopically. • Cluster in grapelike bunches microscopically. • Biochemically differentiated from streptococci by presence of the enzyme catalase. • Biochemically differentiated from other staphylococci by presence of the enzyme coagulase. • Analysis of chromosomal DNA can identify clonal isolates (useful in epidemiologic studies). General Considerations A. Epidemiology. Staphylococcus aureus colonizes the human skin, vagina, nasopharynx, and gastrointestinal tract. Colonization occurs shortly after birth and may be either transient or persistent. Published studies differ widely in estimates of the prevalence of …

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Primary Bacteremia & Endocarditis

Staphylococci (both S aureus and CoNS) have emerged as the two most common organisms cultured from patients with primary bloodstream infections. The term “primary bacteremia” refers to positive blood cultures without an identifiable anatomic focus of infection. Differentiation of primary bacteremia from infective endocarditis (IE), in which infection of the cardiac valves leads to continuous bacterial seeding of the bloodstream, may challenge even the most experienced clinician. Primary S aureus bacteremia is associated with insulin-dependent diabetes, the presence of a vascular graft, and, most significantly, the presence of an indwelling intravascular catheter. Risk factors for IE include structurally abnormal valves, recent injection drug use, and the presence of a prosthetic cardiac …

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Penicillins: Drug-Drug Interactions

Allopurinol The risk of rashes caused by aminopenicillins does not seem to be increased by parallel treatment with allopurinol, as had been suggested before. Aminoglycosides High doses of parenteral penicillin can inactivate aminoglycosides. In patients receiving low doses of aminoglycosides because of reduced renal function this can be clinically important. Parenteral administration of these drugs in neonatal dosages does not seem to produce relevant inactivation, and so temporal separation of the infusions is not required. Piperacillin protected against aminoglycoside nephrotoxicity without reducing its blood concentration; this was possibly a protective effect of co-administered mineral salts. Ciclosporin In a study in lung transplant recipients, ciclosporin nephrotoxicity was potentiated by nafcillin. Methotrexate Beta-lactams …

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Penicillins: Organs and Systems

Respiratory Bronchospasm may be a consequence of penicillin allergy. Acute severe dyspnea with cyanosis has also been observed without symptoms of bronchial obstruction or pulmonary edema. Specific mechanisms for such cases have yet to be identified. Allergic pneumonitis and transient eosinophilic pulmonary infiltrate (Loeffler’s syndrome) are rare. These syndromes have also been observed with penicillin hypersensitivity. In one case, an alveolar allergic reaction, probably due to ampicillin, showed features of an adult respiratory distress syndrome. Nervous system High doses of penicillins, in the order of several million units/day of penicillin G, can produce myoclonic jerks, hyper-reflexia, seizures, or coma. Drowsiness and hallucinations can occur occasionally. Such reactions are due to a …

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Penicillins: Organs and Systems: Liver

Penicillin-induced hepatotoxicity may not be as uncommon as has been thought. There have been three reviews. The first was a comparison of the assessment of drug-induced liver injury obtained by two different methods, the Council for International Organizations of Medical Sciences (CIOMS) scale and the Maria & Victorino (M&V) clinical scale. Three independent experts evaluated 215 cases of hepatotoxicity reported using a structured reporting form. There was absolute agreement between the two scales in 18% of cases, but there was no agreement in cases of fulminant hepatitis or death. The authors concluded that the CIOMS instrument is more likely to lead to a conclusion compatible with the specialist’s empirical approach. In …

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Cellulitis Periorbital & Orbital

Description of Medical Condition An acute, spreading infection of the dermis and subcutaneous tissue. Several entities are recognized. Cellulitis around the eyes is a potentially dangerous periorbital and orbital infection. System(s) affected: Skin/Exocrine, Nervous Genetics: No known genetic pattern Incidence/Prevalence in USA: Unknown Predominant age: N/A Predominant sex: Male = Female Medical Symptoms and Signs of Disease • Lid edema • Rhinorrhea • Orbital pain, tenderness • Headache • Conjunctival hyperemia • Chemosis • Ptosis • Limitation to ocular motion • Increase intraocular pressure • Disease in corneal sensation • Congestion of retinal veins • Chorioretinal stria • Gangrene and sloughing of lids What Causes Disease? • Cellulitis around the eye …

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Cellulitis

Description of Medical Condition An acute, spreading infection of the dermis and subcutaneous tissue. Several entities are recognized: • Cellulitis of the extremities — characterized by an expanding, red, swollen, tender or painful plaque with an indefinite border that may cover a wide area • Recurrent cellulitis of the leg after saphenous venectomy — patients have an acute onset of swelling, erythema of the legs arising months to years after coronary artery bypass. (Surgery using lower extremity veins for bypass grafts.) • Dissecting cellulitis of the scalp — recurrent painful, fluctuant dermal and subcutaneous nodules • Facial cellulitis in adults — a rare event. Patients usually develop pharyngitis, followed by high …

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Brain Abscess

Description of Medical Condition Single or multiple abscesses within the brain, usually occurring secondary to a focus of infection outside the central nervous system. May mimic brain tumor but evolves more rapidly (days to a few weeks). It starts as a cerebritis, becomes necrotic, and subsequently becomes encapsulated. System(s) affected: Nervous Genetics: No known genetic pattern Incidence/Prevalence in USA: Infrequent Predominant age: Median age 30-40 Predominant sex: Male > Female (2:1) Medical Symptoms and Signs of Disease • Recent onset of headache becoming severe • Nausea and vomiting • Mental changes progressing to stupor and coma • Afebrile or low-grade fever • Neck stiffness • Seizures • Papilledema • Focal neurological …

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Anaerobic & Necrotizing Infections

Description of Medical Condition Gangrene is local death of soft tissues due to disease or injury and is associated with loss of blood supply. Anaerobic and necrotizing infections may be associated with gas. System(s) affected: Skin/Exocrine, Cardiovascular Genetics: N/A Incidence/Prevalence in USA: Rare Predominant age: Any Predominant sex: Male = Female Medical Symptoms and Signs of Disease • Local pain • Foul odor • Abnormally dark skin and tissues under skin (dark green to black) • Crepitation (gas) • Fever • Rapid pulse • Fulminant course leading to death without treatment What Causes Disease? • Local injury • Superimposed infection (surface or deep; local or distant) • Carcinoma of large intestine …

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