Viridans streptococci

Oropharynx Streptococci—viridans group Micrococcus Corynebacterium spp. Neisseria Hemophilus spp. Spirochetes... 

Acute pancreatitis can progress to several distinct consequences. Pancreatic fluid collections and pancreatic abscesses can form during the course of acute pancreatitis. Pancreatic necrosis can occur when pancreatic enzymes damage the pancreatic tissue or when pancreatic abscesses become secondarily infected. This infection is usually due to bacteria that are normally found in the gastrointestinal tract, including Escherichia coli, Enterobacteriaceae, Staphylococcus aureus, viridans group streptococci, and anaerobes. 

Aspiration Oral contents Anaerobes, viridans streptococci Gastrointestinal contents with pH increase Enteric gram-negative bacilli... 

Human Viridans streptococci, Staphylococcus aureus, Eikenella corrodens, Elemophilus influenzae, and P-lactamase-producing anaerobic bacteria. 

Infective endocarditis caused by these streptococci typically has a subacute clinical course. The current cure rate is often over 90% unless complications occur, which is the case in more than 30% of patients.17 The majority of viridans streptococci remain very susceptible to penicillin, with most strains having a minimum inhibitory concentration (MIC) of less than 0.125 mcg/mL.15,18 Organisms with decreased susceptibilities are increasing. Therefore, antibiotic susceptibilities need to be assessed in order to determine the most appropriate treatment regimen. 

Viridans streptococci, Streptococcus bovis, HACEK group, Staphylococcus aureus, or community-acquired enterococci in the absence of a primary focus, or... 

As penicillin MICs increase (greater than 0.12 mcg/mL but less than or equal to 0.5 mcg/mL) for viridans group streptococci,... 

TABLE 71-3. Therapy of Native-Valve Endocarditis Caused by Highly Penicillin-Susceptible Viridans Group Streptococci and... 

Patients with PVE caused by penicillin-susceptible strains of viridans streptococci require treatment for 6 weeks with penicillin G or ceftriaxone with or without gentamicin during the initial 2 weeks of therapy. However, if the organism demonstrates less susceptibility to penicillin (MIC greater than 0.12 mcg/mL), a combination therapy with penicillin G or ceftriaxone plus gentamicin should be given for the entire 6 weeks. Vancomycin remains the primary alternative if the patient is allergic to (l-lactams (e.g., penicillins, cephalosporins, etc.). 

Because the progression of infection in neutropenic patients can be rapid, empirical antibiotic therapy should be administered quickly to such patients once fever is documented. Currently, the most commonly used initial antibiotic agent is cefipime, a fourth-generation cephalosporin that has good antipseudomonal coverage as well as adequate coverage against viridans streptococci and pneumococci.23... 

Viridans streptococci than or equal to 30% Increasing resistance to penicillin ... 

In healthy individuals URT flora multiplies in gastric aspirate during treatment with antisecretory compounds and in particular proton pump inhibitors [34, 40, 44], This concerns viridans streptococci, coagulase-negative staphylococci, Haemophilus sp., diphtheroids, Moraxella sp., lactobacilli, and other streptococci, most of which are Gram-positive bacteria. With dedicated measures anaerobic species of oral origin are also recovered [66]. 

Streptococci are a common cause of IE, with most isolates being viridans streptococci. 

Most viridans streptococci are exquisitely sensitive to penicillin G with minimal inhibitory concentrations (MICs) less than or equal to 0.12 meg/ mL. The MIC should be determined for all viridans streptococci and the results used to guide therapy. Approximately 10% to 20% are moderately susceptible (MIC 0.12 to 0.5 mcg/mL). 

In patients with endocarditis of prosthetic valves or other prosthetic material caused by viridans streptococci and Streptococcus bovis, treatment courses are extended to 6 weeks (Table 37-5). 

Therapy for Endocarditis of Prosthetic Valves or Other Prosthetic Material Caused by Viridans Group Streptococci and Streptococcus bovis... 

Complicated intra-abdominal infections (used in combination with metronidazole) caused by E. coli, viridans group streptococci, P. aeruginosa, K. pneumoniae, Enterobacter spec es, or Bacteroides fragilis. 

Intra-abdominal infections Complicated appendicitis and peritonitis caused by viridans group streptococci, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Bacterioides fragilis, Bacterioides thetaiotaomicron, and Peptostreptococcus sp. 

Gram-positive cocci, especially viridans streptococci and Staphylococcus aureus, cause the vast majority of episodes of endocarditis in individuals without a prosthetic heart device. In prosthetic device endocarditis coagulase-negative staphylococci and S. aureus are major pathogens early after the implantation of the device later episodes of prosthetic device associated endocarditis are more likely due to viridans streptococci. Enterococci-bacteremia is associated with lesions in the digestive tract and frequently causes endocarditis. Gram-negative bacilli cause <5% of episodes of bacterial endocarditis. 

The clinical uses of penicillin G include endocarditis caused by S. viridans (or Streptococcus hovix), pharyngitis (group A (3-hemolytic streptococci), cat bite cellulitis Pasteurella multocida), and syphilis (Treponema pallidum). 

Viridans streptococci Neisseria meningitidis Neisseria gonorrhoeae Haemophilus influenzae Escherichia coli Klebsiella Proteus mirabilis Pseudomonas ... 

Viridans streptococci Penicillin Cephalosporin (first- or third-generation),2 vancomycin... 

Subacute Viridans streptococci, enterococci Penicillin + gentamicin Vancomycin + gentamicin... 

Staphylococcus epidermidis. Streptococcus (Group C/F), Streptococcus (Group G), Staphylococcus saprophyticus, Streptococcus agalactiae, Viridans group streptococci... 

CG Dowson, A Hutchison, N Woodford, AP Johnson, RC George, BG Spratt. Penicillin-resistant viridans streptococci have obtained altered penicillin-binding protein... 

Answer B (Amoxicillin). The multiple extractions can lead to bacteremia while the mitral valve stenosis and cardiac insufficiency place him at risk for developing endocarditis. The present American Heart Association guidelines indicate amoxicillin (3 gm 1 hour prior to procedure and 1.5 gm 6 hours after original dose.) Vancomycin would only be appropriate if the patient was allergic to penicillins. Tetracycline and cotrimoxazole are bacteriostatic and not effective against the viridans group of Streptococci, the usual causative organism. Imipenem is also inappropriate since its spectrum is too broad. 

Viridans streptococci Other streptococci Staphylococci Coagulase positive Coagulase negative Enterococci... 

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