Penicillin endocarditis

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. 

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

Therapy for Native-Valve or Prosthetic-Valve Enterococcal Endocarditis Caused by Strains Susceptible to Penicillin, Gentamicin, and Vancomycin... 

Aqueous crystalline penicillin G sodium or 24 million units/24 hours IV either continuously or in four to six equally divided doses 4 IB Patients with endocarditis caused by penicillin-resistant (MIC greater than 0.5 mcg/mL) strains should be Seated with regimen recommended for enterococ-... 

Enterococcal endocarditis ordinarily requires 4 to 6 weeks of high-dose penicillin G or ampicillin, plus gentamicin for cure (Table 37-8). A 6-week course is recommended for patients with symptoms lasting longer than 3 months and those with PVE. 

Severe staphylococcal Infections - Severe staphylococcal infections (including methicillin-resistant staphylococci) in patients who cannot receive or who have failed to respond to penicillins and cephalosporins, or who have infections with resistant staphylococci. Infections may include endocarditis, bone infections, lower respiratory tract infections, septicemia, and skin and skin structure infections. 

Prop/ y/acf/c-Although no controlled clinical efficacy studies have been conducted, IV vancomycin has been suggested for prophylaxis against bacterial endocarditis in penicillin-allergic patients who have congenital... 

Empiric treatment for subacute endocarditis likely to be caused by penicillin-sensitive streptococci consists of high dose penicillin G (6 x 3 million units i.v. daily) plus gentamicin (1x3 mg/kg). In acute endocarditis a staphylococcal etiology is more likely and, therefore, gentamicin is combined with (flu)cloxacillin (6 x 2 g i.v. daily). 

Streptococci are generally highly sensitive to penicillin G (MIC <0.1 mg/1), albeit that some strains are more resistant (MIC O.I-I.O mg/1). Thus, streptococcal endocarditis can be treated with a... 

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). 

Streptococcal infections Pharyngitis, rheumatic fever, otitis media and even for subacute bacterial endocarditis. Staphylococcal infections Penicillinase resistant penicillin can be used. Meningococcal infections Meningitis other infections caused by meningococci. 

Penicillins are also used in the prophylaxis of rheumatic fever, sexually transmitted diseases e.g. gonorrhoea and syphilis and bacterial endocarditis. 

It is used in all forms of tuberculosis along with other antitubercular drugs. Other indications are tularemia, plague, brucellosis, bacterial endocarditis, entero-coccal endocarditis. Used concomitantly with penicillin G for synergistic effect in the treatment of enterococcal endocarditis when other antibiotics are ineffective or contraindicated. 

The aminoglycosides include streptomycin, neomycin, kanamycin, amikacin, gentamicin, tobramycin, sisomicin, netilmicin, and others. They are used most widely against gram-negative enteric bacteria, especially in bacteremia and sepsis, in combination with vancomycin or a penicillin for endocarditis, and for treatment of tuberculosis. 

Penicillin plus streptomycin is effective for enterococcal endocarditis and 2-week therapy of viridans streptococcal endocarditis. Gentamicin has largely replaced streptomycin for these indications. Streptomycin remains a useful agent for treating enterococcal infections, however, because approximately 15% of enterococcal isolates that are resistant to gentamicin (and therefore to netilmicin, tobramycin, and amikacin) will be susceptible to streptomycin. 

Gram-positive cocci Enterococcus faecalis Endocarditis or other serious infection (bacteremia] Ampicillin or penicillin G + gentamicin or streptomycin Vancomycin + gentamicin or streptomycin... 

Staphylococcus aureus Abscesses bacteremia cellulitis endocarditis osteomyelitis pneumonia others If methicillin-sensitive nafcillin or oxacillin If methicillin-resistant vancomycin gentamicin or rifampin 1 st-generation cephalosporin clindamycin erythromycin trimethoprim-sulfamethoxazole a penicillin + a penicillinase inhibitor... 

Streptococcus (viridians group) Bacteremia endocarditis Penicillin G gentamicin Ist-generation cephalosporin erythromycin azithromycin clarithromycin vancomycin gentamicin... 

Rifampin is used in a variety of other clinical situations. An oral dosage of 600 mg twice daily for 2 days can eliminate meningococcal carriage. Rifampin, 20 mg/kg/d for 4 days, is used as prophylaxis in contacts of children with Haemophilus influenzae type b disease. Rifampin combined with a second agent is used to eradicate staphylococcal carriage. Rifampin combination therapy is also indicated for treatment of serious staphylococcal infections such as osteomyelitis and prosthetic valve endocarditis. Rifampin has been recommended also for use in combination with ceftriaxone or vancomycin in treatment of meningitis caused by highly penicillin-resistant strains of pneumococci. 

In the treatment of entero-coccal endocarditis with penicillin and streptomycin or cryptococcal meningitis infections with amphotericin B in combination with flucytosine. 

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