Materia Medica

METFORMIN: OPTIMAL DOSING AND MYTHS SURROUNDING LACTIC ACIDOSIS ccording to the CDC, acute upper respiratory infections are the 3rd leading primary diagnosis at ambulatory care office visits in the U.S.1 One of the more common upper respiratory infections is rhinosinusitis which describes an inflammation of one or more of the paranasal sinuses.2 Symptoms, which last 4 weeks or fewer in acute cases, include nasal congestion, facial pain, rhinorrhea, hyposmia, and sneezing, with fever and malaise possible. Rhinosinusitis affects ~16% of the population annually, but most acute sinus infections are caused by viruses.2 Moreover, most of these infections improve within 2 weeks without antibiotic treatment for the majority of patients.1,2,3 Acute bacterial rhinosinusitis (ABRS) develops only in about 0.5-2% of patients with acute rhinosinusitis.4 Several predisposing host factors and environmental factors are associated with ABRS (Table 1). The diagnosis of ARBS is based on major and minor symptoms (Table 2). The predominant pathogens thought to cause ABRS are Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus and Streptococcus pyogenes in descending order of prevalence in adults (Table 3).2,3 Routine childhood vaccinations have reduced the incidence of vaccine-covered serotypes of S. pneumoniae, as well as the incidence of H. influenzae type b in adults and children.3,4 Importantly, the true incidence of ABRS caused by these pathogens is relatively poorly understood since these bacteria are frequent respiratory tract colonizers and microbiological studies are not always able to differentiate pathogenic bacteria from colonizing bacteria. Antibiotic treatment is commonly overprescribed for acute rhinosinusitis due to the difficulty differentiating between viral and bacterial etiology.5 Given the high prevalence of sinusitis infections, appropriate use of antibiotics and avoiding unnecessary antibiotic use is crucial in the treatment of rhinosinusitis to prevent unnecessary exposure to potential adverse effects and to prevent the development of antibiotic-resistant bacteria. Acute rhinosinusitis impacts the lives of those affected by impairing daily functioning, negatively affects quality of life and causes significant physical symptoms.6 Therefore, it is important to understand treatment options, including indications for antibiotics, the appropriate selection of antibiotics, as well as adjunct therapy to treat symptoms. The purpose of this article is to briefly review the diagnosis of ABRS and differentiation from viral rhinosinusitis, discuss appropriate versus inappropriate antibiotic use to improve treatment and prevent development of antibiotic resistance, and to review the appropriate treatment for ABRS, including antibiotic and adjunct therapy options.