Iranian Registry of Infective Endocarditis (IRIE): Time to relook at the guideline, regarding to regional differences

Infective endocarditis (IE) is a relatively rare and potentially fatal disease despite notable advances in medical and surgical treatment. The patterns of the disease in terms of its epidemiology, pathological basis, and antibiotic era vary considerably. The annual global incidence of IE has been estimated to be 3 to 10 per 100,000 people [1], [2], [3], similar in low-income and industrialized countries [4]. However, whereas rheumatic heart diseases (RHDs) have been suggested as the main key risk factor for IE in developing countries [5], [6], [7], degenerative valve diseases, prosthetic valves, intracardiac devices, and malignancies are increasingly associated with IE in developed countries [8]. Moreover, recent decades have witnessed a shift in the incidence of IE, from young adults to the elderly, reflecting medical and care advances in the control and prevention of IE [9]. The results of epidemiological studies vary with respect to the microbial pathogenicity of IE. Although the type of pathogen has not substantially changed over time—with Streptococcus, Staphylococcus and Enterococcus still accounting for more than 80% of all cases—the specific subtypes of microorganisms require a repartition of groups most at risk [10], [11]. In conjunction with these issues, even with notable advances in diagnostic technology, improvements in antimicrobial selection, and formulation of new guidelines for the proper management of IE, the morbidity and mortality of the disease remain high inasmuch as 1 in 5 patients die during the initial hospital admission, which can be due to changes in the type and virulence of the infecting organisms and the changes in the population at risk of developing IE [12], [13], [14]. The considerable variations in the epidemiology, underlying heart diseases, pathogenic sources, and risk and prognostic factors of IE render the prompt identification of the clinical and epidemiological aspects of the disease with a view to devising the optimal management strategy and preventing the adverse consequences in any given society essential. Such assessment assumes even more significance in the context of countries like Iran, where there is a dearth of up-to-the-minute data in the face of evidence for significant changing patterns of IE [15], [16]. Indeed, our exhaustive literature search of credible sources by employing main keywords yielded very little information on the epidemiological aspects of IE in our population. Hence, in the present study, conducted in a tertiary referral center, we sought to address the epidemiological aspects of IE vis-a-vis its etiology, underlying heart diseases, principal microbial pathogens, and prognosis.