The macrolides

Abstract

Erythromycin, which was introduced over 50 years ago, was the first macrolide to be used clinically. "New" macrolides, for the treatment of patients with various infectious diseases, were not clinically introduced until 40 years later. The pharmacokinetic and adverse events profile of erythromycin initially limited its use to an alternative agent for patients with allergy to beta-lactam agents. However, the emergence of atypical and/or new pathogens and the ongoing escalation of acquired antimicrobial resistance has impacted on the empirical and organism directed therapy of infectious diseases. Azithromycin and clarithromycin were developed by enhancing the basic macrolide structure. Some of the basic features associated with these new agents include a pharmacokinetic profiles that allow once or twice daily dosing with a much lower incidence of side effects and a substantially broader spectrum of activity which includes some Gram-negative bacilli, atypical pathogens and new, unconventional or uncommon pathogens. Clinical trial data has supported the use of "new" macrolides in a wide range of clinical indications, however, some specific indications are currently restricted to treatment with either azithromycin or clarithromycin. Macrolide resistance is a class effect and depending on the mechanism will confer either low or high level resistance. While resistance is problematic, it does not always result in clinical failure. The macrolides are a valuable class of antimicrobial agent and play an important role in the management of infectious diseases.

Suscetibilidade à azitromicina de isolados bacterianos de processos infecciosos em cães e gatos

“…veterinária (Hansen et al 2002). A azitromicina possui um amplo espectro de ação apresentando atividade contra bactérias gram-positivas e uma gama de bactérias gramnegativas (Maskell et al 1990, Neu 1991, Edelstein & Edelstein 1999.…”

Azithromycin for Indigenous children with bronchiectasis: study protocol for a multi-centre randomized controlled trial

“…Azithromycin is also associated with increased risk of resistance to other antibiotic classes, especially the beta-lactams, in respiratory bacterial flora [40]. While resistance is problematic and treatment failure has been reported, [41-43] macrolides still play an important role in managing many infectious diseases, including other respiratory infections, trachoma and sexually transmitted infections [44,45]. The current study is carefully monitoring antibiotic resistance in potential respiratory bacterial pathogens colonising the nasopharynx.…”

Chalcomycins from Marine-Derived Streptomyces sp. and Their Antimicrobial Activities

“…The global epidemic of continually rising resistance has become a critical threat to human health and therefore the discovery of new antibiotics is urgently needed [2]. Macrolide antibiotics such as erythromycins, tylosins, avermectins, and milbemycins have significant activity against a broad spectrum of Gram-positive bacteria [3,4,5], playing an important role in the chemotherapy of infectious diseases [6,7]. Macrolides are usually characterized by a 12-, 14-, 16-, 18-, 20-, 22-, or 24-membered lactone ring with one or more sugar moieties [3,8].…”