Cephalosporins

Cephalosporins are bactericidal ?-lactam antibiotics. They inhibit the enzymes in the cell wall of bacteria susceptible to disrupt cell synthesis. There are 5 different generations of cephalosporins (see table: Cephalosporins *). Cephalosporins * drug administration route 1st generation Cefadroxil Oral cefazolin Parenteral administration Cephalexin Oral cephradine oral 2nd generation Cefaclor Oral cefotetan Parenteral administration Parenteral administration cefoxitin cefprozil oral cefuroxime parenteral or oral third generation Cefdinir Oral Cefditoren oral cefixime cefotaxime Oral Parenteral administration cefpodoxime ceftazidime Oral Parenteral administration ceftibuten Oral ceftriaxone Parenteral administration 4th Generation Cefepime parenteral administration 5th generation Ceftarolin parenteral administration Pharmacology cephalosporins penetrate well into most body fluids and the extracellular fluid of most tissues, especially in inflammatory processes (promote the diffusion). However, the only cephalosporins, which reach a CSF levels, which is high enough to have meningitis behandlen following: ceftriaxone cefotaxime ceftazidime Cefepime All cephalosporins penetrate poorly into the intracellular fluid and the vitreous humor. Most cephalosporins are excreted primarily in the urine, so that their dose should be adjusted in patients with renal insufficiency. Cefperazon and ceftriaxone do not require such dose adjustment, since these are biliary excretion also in a significant amount. Indications cephalosporins are bactericidal for most of the following pathogens: Gram-positive bacteria Gram-negative bacteria cephalosporins are divided into different generations (see Table: Some clinical applications of the 3rd and 4th generations of cephalosporins). The drugs of the first generation are mainly active against gram-positive organisms. Higher generations have a broader spectrum of activity against aerobic gram-negative rods. The 5th generation cephalosporin Ceftarolin is effective against methicillin-resistant Staphylococcus aureus. Cephalosporins have the following limitations: a lack of activity against enterococci (except for Ceftarolin, which is active against Enterococcus faecalis, not E. faecium) Lack of activity against methicillin-resistant staphylococci (except for Ceftarolin) lack of activity against gram-negative anaerobic bacilli (except cefotetan and cefoxitin) first-generation cephalosporins, these drugs have excellent activity against Gram-positive cocci, the first generation of orally active cephalosporins is often used for uncomplicated skin and soft tissue infections that are usually caused by staphylococcus and streptococcus. Parenteral cefazolin is widely used in endocarditis due to methicillin-sensitive S. aureus and for prophylaxis before cardiothoracic, orthopedic, abdominal and pelvic surgical Eingriffen.Zweite generation cephalosporins and cephamycins second-generation cephalosporins are effective against certain Gram-positive cocci Gram-negative rods cephamycins are effective against Bacteroides sp, including B. fragilis These medicines may be somewhat less effective against gram-positive cocci than cephalosporins of the first generation. 2nd generation cephalosporins and cephamycins are often used in polymicrobial infections with gram-negative bacilli and gram-positive cocci. Since cephamycins are effective against Bacteroides sp, they can in infections with V. a. be used anaerobes (z. B. intra-abdominal sepsis, decubitus ulcers, infected diabetic feet). In some hospitals, however, these bacteria are no longer against cephamycins empfindlich.Cephalosporine third generation These drugs are effective against Haemophilus influenzae and some Enterobacteriaceae (eg., Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis) that do not express ?-lactamase or ampC produce extended spectrum ?-lactamase (ESBL). Ceftazidime is also effective against P. aeruginosa. Pseudomonas aeruginosa Some cephalosporins third generation have a relatively weak activity against Gram-positive cocci. Oral cefixime and ceftibuten have only a low activity against S. aureus and when they are used in skin and soft tissue infections, should be limited to simple infections caused by streptococcus. These cephalosporins, as well as the fourth-generation cephalosporin, many clinical applications (see table: Some clinical applications of the 3rd and 4th generations of cephalosporins) .Vierte generation cephalosporin Cephalosporin The 4th generation cefepime is effective (against Gram-positive cocci similar to cefotaxime ) Gram-negative bacteria (increased activity), including P. aeruginosa (similar ceftazidime) ESBL-producing K. pneumoniae and E. coli and ampC ?-lactamase-producing Enterobacteriaceae, such as Enterobacter sp Some clinical applications of the 3rd and 4th generations of cephalosporins drug indications Remarks 3rd and 4th generation cephalosporins polymicrobial infections with gram-negative bacteria and gram-positive cocci (eg. As intra-abdominal sepsis, Dekubitusulzera, diabetic foot infections) necessary to use when other medicines to cover anaerobes or enterococci ceftriaxone and some other medicines 3rd Generation Community-acquired pneumonia is used together with a macrolide to atypical pathogens (mycoplasma , Chlamydophila sp, Legionella sp) cover cefotaxime ceftriaxone acute meningitis, presumably by Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitides or caused used together with ampicillin to Listeria monocytogenes, and together with vancomycin to S. pneumoniae Penicillin with reduced sensitivity (up to MIC results *) cover cefpodoxime (oral) uncomplicated skin and soft tissue infections caused not be used when a is methicillin-resistant Staphylococcus aureus suspected of staphylococcal or streptococcal target. Ceftazidime Empirical therapy for post-surgical euro meningitis to cover Pseudomonas aeruginosa. Used in conjunction with vancomycin to cover methicillin-resistant S. aureus endocarditis caused by ceftriaxone HACEK organisms – endocarditis by penicillin-sensitive Streptococcus causes – Lyme disease with neurological complications (except for isolated Bell’scher’s palsy), carditis or arthritis – uncomplicated gonococcal infections, chancroid or both individuals in * Dose were reported pneumococcal strains that are resistant to ceftriaxone and cefotaxime were reported, and guidelines recommend that CSF tribes who micrograms have an MIC ? 1.0 / ml, are classified as non-sensitive to 3rd generation cephalosporins , HACEK = Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, and Kingella spp; MIC = minimum inhibitory concentration. Fifth-generation cephalosporin Cephalosporin The 5th generation Ceftaroline is effective against methicillin-resistant S. aureus (MRSA) and E. faecalis Its activity against other gram-positive cocci and Gram-negative Bacili similar to that of the cephalosporin of the third generation. It is not effective against active Pseudomonas sp. Contraindications cephalosporins are contraindicated in patients who are allergic to them or who had an anaphylactic reaction to penicillin. Ceftriaxone has the following contraindications: ceftriaxone IV does not involve Ca-containing infusion solutions to be administered (including continuous Ca-containing infusions such as parenteral nutrition) in neonates ? 28 days because the precipitation of ceftriaxone-calcium salt is a risk. Fatal reactions with ceftriaxone-calcium precipitates in the lungs and kidneys of newborns have been described. In some cases, different infusion lines were used and, ceftriaxone and calcium-containing solutions at different times. So far, intravascular or pulmonary precipitates were described only in newborns, but not in other patients, treated with ceftriaxone and calcium-containing infusion solutions. However, since an interaction between ceftriaxone and i.v. Ca-containing solutions in other patients as possible in newborns, should theoretically they are not mixed within 48 h or patients – regardless of age – are given (at 5 half-lives of ceftriaxone), not even via different infusion lines at different sites. There are no data on possible interactions between ceftriaxone and oral calcium-containing products or interaction between i.m. Ceftriaxone and calcium-containing products (iv or taken orally). Ceftriaxone should not babies suffering from hyperbilirubinemia or be given to premature babies, as in vitro, displace bilirubin from serum albumin ceftriaxone and potentially can cause kernicterus. Use during pregnancy and lactation Cephalosporins are in pregnancy category B (animal studies show no risk, human experience is incomplete or animal studies show risk, but human studies do not). Cephalosporins are excreted into breast milk and may alter the intestinal flora of the child. For this reason, is often discouraged by the application during lactation. Side effects The most significant side effects included hypersensitivity reactions (most common) Clostridium difficile-indexed diarrhea (pseudomembranous Kolitis- Clostridium difficile-induced diarrhea) leukopenia thrombocytopenia Positive Coombs test (although haemolytic anemia is extremely rare) The most common systemic adverse reactions are hypersensitivity reactions; Rash is common, but IgE-mediated immediate reactions such as urticaria and anaphylaxis are rare. A cross allergy between cephalosporins and penicillins is rare. Cephalosporins may be given cautiously to patients in which anamnestic evidence of delayed hypersensitivity to penicillins exist. However, in patients who have responded anaphylactic to penicillin, cephalosporins should not be mixed. In i.m. Application can cause pain at the injection site, as well, a thrombophlebitis after i.v. Application occur. Cefotetan can have a disulfiram-like effect and cause nausea and vomiting, when ethanol is added. If giving up cefotetan prothrombin time / INR and PTT can also increase, this effect is reversible with vitamin K administration.

Health Life Media Team

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