Antimicrobials broad-spectrum

Tetracyclines are produced by various Streptomyces strains and are extensively applied in human and veterinary medicine. They display a broad spectrum of antimicrobial activity in combination with low toxicity and can be applied orally. The most commonly prescribed tetracycline drugs are tetracycline itself and oxytetracycline, an oxygenated derivative, which are directly isolated from fermentation liquors, and doxycycline whose partial synthesis from oxy-... 

Widespread clinical acceptance continues to be accorded to the cephalosporins, and the field is extremely active as firms search for the ultimate contender. Among the characteristics desired is retention of the useful features of the older members (relatively broad spectrum, less antigenicity than the penicillins, relative insensitivity toward 3-lactamases, and convenience of administration) while adding better oral activity and broader antimicrobial activity (particularly potency against Pseudomonas, anaerobes, meningococci, cephalosporinase-carrying organisms, and the like). To a considerable extent these objectives have been met, but the price to the patient has been dramatically increased. 

Parabens kill molds and fungi. They are used synergistically with bactericides to make broad-spectrum antimicrobials. 

Sodium benzoate is used as a broad-spectrum antimicrobial, inhibiting bacteria, molds, and yeasts. The high acid content of the soft drink is necessary for the preservative action. Sodium citrate buffers the acids, so the pH stays low (acidic). It also emulsifies any fats or fat-soluble compounds in the flavorings, keeping them in solution. 

The magaiitins are a class of hnear, cationic, faciaUy amphipathic and hehcal antibacterial peptides derived from frog skin [51]. The magaiitins exhibit highly selective and potent antimicrobial activity against a broad spectrum of organisms [52, 53]. As these peptides are faciaUy amphipathic, the magainins have a cationic heli-... 

A broad-spectrum antimicrobial target must be conserved across all pathogens of interest within a therapeutic product profile, essential for bacterial growth, and either absent, substantially different or non-essential in humans. PDF meets all of these criteria and is one of the most promising unexploited bacterial targets in the search for new antibiotics with a novel mode of action. 

Culture if keratitis is severe or sight-threatening. Otherwise, cultures or smears are used only if the corneal infiltrate is chronic or unresponsive to broad-spectrum antimicrobial therapy.19... 

Empirical selection of antimicrobial therapy for ventilator-associated, health care-associated, and hospital-associated pneumonia is broad spectrum however, once culture and susceptibility information are available, the therapy should be narrowed (deescalation) to cover the identified pathogen(s). 

The severity of a patient s infection, based on the PEDIS scale, guides the selection of empirical antimicrobial therapy. While most patients with grade 2 diabetic foot infections can be treated as outpatients with oral antimicrobial agents, all grade 4 and many grade 3 infections require hospitalization, stabilization of the patient, and broad-spectrum IV antibiotic therapy.31... 

Antimicrobial regimens for secondary intraabdominal infections should cover a broad spectrum of aerobic and anaerobic bacteria from the GI tract. 

Candida species are the most common opportunistic fungal pathogens encountered in hospitals, ranking as the third to fourth most common cause of nosocomial bloodstream infections in United States Hospitals.18 The incidence of nosocomial candidiasis has increased steadily since the early 1980s, with the widespread use of central venous catheters, broad-spectrum antimicrobials, and other advancements in the supportive care... 

O A risk assessment should be performed at presentation of febrile neutropenia to identify low-risk patients for potential outpatient treatment (see Table 96-3). Patients who do not meet low-risk criteria should be hospitalized for parenteral administration of broad-spectrum antibacterials. The IDSA has published evidence-based guidelines for the management of febrile neutropenia5,12 (Fig. 96-1). The choice of initial antimicrobial agent(s) depends on the following factors ... 

Spectrum of activity A qualitative term that describes the number of different bacterial species that are susceptible to an antimicrobial regimen. Generally, broad-spectrum activity refers to regimens that possess activity against many bacterial species, whereas narrow-spectrum therapy refers to activity against a few bacterial species. 

A number of substances may interfere with stool examination. Particulate materials such as barium, antacids, kaolin, and bismuth compounds interfere with morphologic examination, and oily materials such as mineral oil create small, refractile droplets that make examination difficult. Antimicrobial agents, particularly broad-spectrum antimicrobial agents, may suppress amebae. If any of these substances have been used, specimens should not be submitted until the substances have been cleared (generally 5 to 10 days). A fecal specimen may appear satisfactory by gross examination when there is still barium, etc., which can interfere with microscopic examination. 

Among pharmaceuticals, antibiotics have become of special concern in recent years. The reason is that these substances are continuously being introduced into the environment and may spread and maintain bacterial resistance in the different compartments. Sulfonamides are very commonly used antimicrobials in humans but mainly in veterinary medicine, due to their broad spectrum of activity and low cost, being the second most widely used veterinary antibiotic in the EU. Their occurrence has been reported in all kinds of water matrices their high excretion rates (after their intake by humans of livestock) and high water solubility make them very ubiquitous and persistent pollutants in the environment. 

Diarrhea is a well-known complication of antibiotic therapy. Rates of antibiotic-associated diarrhea (AAD) vary from 5 to 25%. Some antibiotics are more likely to cause diarrhea than others, specifically, those that are broad spectrum and those that target anaerobic flora. This paper reviews the effects of antibiotics on the fecal flora as well as host factors which contribute to AAD. Clinical features and treatment of AAD are also described. Prevention of AAD rests on wise antibiotic policies, the use of probiotics and prevention of acquisition in the hospital setting. Data from clinical trials suggest that poorly absorbed antimicrobials might have a decreased risk of causing AAD and Clostridium difficile-associated disease, as concluded from studies of antibiotics used for preoperative bowel decontamination and poorly absorbed antibiotics used for traveler s diarrhea. Controlled trials would prove this but are not yet available. Probiotics may be a good adjunct to poorly absorbed antibiotics to minimize the risk of diarrhea associated with antibiotics. 

Rifaximin is a synthetic rifamycin derivative, which acts by inhibiting bacterial ribonucleic acid (RNA) synthesis [48]. It is virtually unabsorbed after oral administration and is, therefore, used primarily to treat gastrointestinal infections. Rifaximin possesses a broad spectrum of antimicrobial activity, covering Gram-positive and Gram-negative bacteria, both arerobic and anaerobic [49], Several studies [44, 49-62] have shown that in patients with HE rifaximin displays an efficacy similar to that of lactulose and neomycin (table 1). A recently published study [62] compared the efficacy and safety of... 

Due to the frequent difficulty of doing cultures before giving an antibacterial drug, topical treatment often requires the use of broad-spectrum antibiotics. However, the selection of resistant strains, especially via the use of broad-spectrum antimicrobials with marked systemic dif-... 

PMC has been associated most often with broad-spectrum antimicrobials, including clindamycin, ampicillin, or third-generation cephalosporins. 

Broad-spectrum antimicrobial therapy is not generally required, except for some severe cases. 

Monotherapy with broad-spectrum parenteral antimicrobials, along with appropriate medical and/or surgical management, is often effective in treating moderate to severe infections (including those in which osteomyelitis is present). 

Broadband, 74 658 Broadband analysis, 75 469 Broad band gap semiconductors, 25 17 Broad spectrum antimicrobial agents, 24 604... 

Potential therapeutic applications of host defense peptides also include the lantibiotic nisin. Indeed, nisin has had an impressive history as a food preservative with FDA approval in 1988 for use in pasteurized, processed cheese spreads. The attractiveness of nisin as a potential therapeutic is also enhanced due to its relative resistance to proteases and broad spectrum Gram-positive antimicrobial activity including multidrug-resistant strains. Biosynexus Inc. has licensed the use of nisin for human clinical applications and Immucell Corp. has licensed the use of Mast Out, an antimastitic nisin-containing product, to Pfizer Animal Health." Indeed, nisin formulations have been used as an active agent in the topical therapies Mast Out and Wipe-Out for bovine mastitis, an inflammatory disorder of the udder that is the most persistent disease in dairy cows." ... 

Slover CM, Rodvold KA, Danziger EH. (2007) Tigecycline A novel broad-spectrum antimicrobial. Ann Pharmacother 41 965-972. 

Uses. As broad-spectrum antimicrobial cold sterilant/disinfectant for hospital equipment as tanning agent for leather as tissue fixative as cross-linking agent for proteins as preservative in cosmetics as therapeutic agent for warts, hyperhidrosis, and dermal mycotic infections in X ray processing solutions and film emulsion as a disinfectant in the beauty industry... 

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