Etiología y resistencia a antimicrobianos de la infección no complicada del tracto urinario / Etiology and antimicrobial resistance of uncomplicated urinary tract infections

La infección urinaria no complicada en mujeres es un motivo frecuente de consulta e indicación de antimicrobianos. El objetivo de este estudio fue definir etiología y resistencia a antimicrobianos en episodios de infección urinaria no complicada. Este estudio prospectivo incluyó mujeres premenopáusicas no embarazadas, con infección urinaria no complicada, que consultaron en un hospital público y tres centros privados de las ciudades de Buenos Aires y La Plata (2011-2013). La edad media de 138 pacientes con infección confirmada por urocultivo fue 28 años. El diagnóstico fue cistitis en 97 (70%) y pielonefritis en 41 (30%). Las frecuencias de los microorganismos aislados fueron: Escherichia coli 97 (70%), Staphylococcus saprophyticus 24 (17%), Proteus spp. 10 (7%), Klebsiella spp. 5 (4%), Enterococcus spp. 1 (0.7%) y Pseudomonas aeruginosa 1 (0.7%). Las frecuencias de resistencia a antimicrobianos fueron: ampicilina-sulbactam 51 (37%), cefalexina 39 (28%), trimetoprima/sulfametoxazol 31 (22%), nitrofurantoína 17 (12%), gentamicina 10 (7%) y ciprofloxacina 7 (5%). La frecuencia de resistencia a ampicilina-sulbactam, trimetoprima/sulfametoxazol y cefalexina es mayor que las previamente publicadas en Argentina, lo que limita su recomendación para el tratamiento empírico. Una mejor comprensión de la etiología y la susceptibilidad antimicrobiana local permite el diseño de pautas más adecuadas para el tratamiento empírico.

Uncomplicated urinary tract infections rank among the most frequent bacterial infections in women in the outpatient setting and represent a major cause of antimicrobial prescription. The aims of this study were to assess frequencies and antimicrobial resistance of current uropathogens causing uncomplicated urinary tract infection. In a prospective multicenter study, patients were recruited in ambulatory settings of four participating hospitals between June 2011 and December 2013. We analyzed 138 patients that met clinical and bacteriological diagnostic criteria. The mean age was 28 years. Cystitis was defined in 70% (n: 97) and pyelonephritis in 30% (n: 41). Frequencies of isolated microorganisms were: Escherichia coli 70% (n: 97), Staphylococcus saprophyticus 17% (n: 24), Proteus spp. 7% (n: 10), Klebsiella spp. 4% (n: 5), Enterococcus spp. and Pseudomonas aeruginosa 1 (0.7%) each. The antimicrobial resistance was: ampicillin-sulbactam 37% (n: 51) cephalexin 28% (n: 39), trimethoprim/sulfamethoxazole 22% (n: 31), nitrofurantoin 12% (n: 17), gentamicin 7% (n: 10) and ciprofloxacin 5% (n: 7). The levels of resistance found for ampicillin-sulbactam, trimethoprim/sulfamethoxazole and cephalexin were higher than those previously reported in Argentina. A better knowledge of the etiology and local antimicrobial susceptibility allows the design of more adequate guidelines for empirical treatment.

Etiología aerobia de apendicitis aguda en adultos: Estudio multicéntrico de la sepsis abdominal en Argentina / Aerobic etiology of acute appendicitis in adults. Multicenter study of abdominal sepsis in Argentina

El tratamiento antibiótico de las apendicitis agudas se decide empíricamente basándose en la información epidemiológica. Las resistencias son variables entre regiones y los datos de Argentina son escasos. En el contexto de un estudio multicéntrico, observacional, de infecciones abdominales, se efectuó el análisis de los pacientes adultos con diagnóstico de apendicitis, incorporados al estudio entre enero 2014 y junio 2015, en 16 centros de 5 provincias argentinas. El objetivo fue analizar los gérmenes aeróbicos prevalentes, su resistencia a antibióticos y el patrón de prescripción antimicrobiana. Se estudiaron 131 apendicitis. Se aislaron 184 bacterias aerobias (1.4 bacterias/episodio): Escherichia coli 106 (57.6%), Klebsiella spp 16 (8.7%), Pseudomonas aeruginosa 19 (10.3%), Enterobacter spp. 2 (1%), otros bacilos Gram negativos 5 (2.7%). Enterococcus spp. 16 (8.7%) y otros cocos Gram positivos 20 (10.9%). La resistencia de E. coli y enterobacterias a ampicilina/sulbactam fue mayor a 34% y a ciprofloxacina mayor a 31%. En cambio, la resistencia de enterobacterias a piperacilina/tazobactam fue 4.8%, a ceftriaxona 9.5% y no se halló resistencia a carbapenemes. Respecto a amikacina fue 3.6% y a gentamicina 8.2%. En función de los resultados, el uso de quinolonas o de ampicilina/sulbactam para el tratamiento de las apendicitis debiera ser desaconsejado. Los esquemas basados en aminoglucósidos debieran ser jerarquizados en función de la sensibilidad hallada y su bajo impacto en la inducción de resistencias.

Antibiotic treatment for acute appendicitis is empirically chosen, based on epidemiological information. Resistance rates are different between regions and there are limited data on the situation in Argentina. As a part of a multicenter, observational study of abdominal infections, we performed the analysis of adult patients diagnosed with appendicitis, enrolled in 16 centers of 5 provinces, between Jan/01/2014 and Jun/30/2015. The aim was to analyze the prevalent aerobic pathogens, their resistance rates and the antimicrobial prescription pattern. On a total of 131 appendicitis cases analyzed, we found 184 aerobic pathogens (1.4 bacteria/episode): Escherichia coli 106 (57.6%), Klebsiella spp 16 (8.7%), Pseudomonas aeruginosa 19 (10.3%), Enterobacter spp. 2 (1%), other Gram negative bacilli 5 (2.7%); Enterococcus spp. 16 (8.7%) and other Gram positive cocci 20 (10.9%). The resistance rate of E. coli and enterobacteria to ampicillin/sulbactam was greater than 34% and greater than 31% to ciprofloxacin. However, the resistance of enterobacteria to piperacillin/tazobactam was 4.8%, to ceftriaxone 9.5%, to amikacin 3.6% and 8.2% to gentamicin. No resistance to carbapenems was found. The choice of quinolones or ampicillin/sulbactam for the treatment of appendicitis should be discouraged in our context, due to the high rates of resistance found in this prevalent etiology. Aminoglycoside-based treatments should be considered, given the findings of high antibiotic susceptibility and their low impact on the induction of resistance.

Consenso Intersociedades para el manejo de infecciones respiratorias: bronquitis aguda y enfermedad pulmonar obstructiva crónica / [Inter-society consensus for the management of respiratory infections: acute bronchitis and chronic obstructive pulmonary disease].

The Argentine Society for Infectious Diseases and other national societies issued updated practical guidelines for the management of acute bronchitis (AB) and reactivations of chronic obstructive pulmonary disease (COPD) with the aim of promoting rational use of diagnostic and therapeutic resources. AB is a condition characterized by inflammation of the bronchial airways which affects adults and children without underlying pulmonary disease. It is usually caused by a virus. The diagnosis is based on clinical findings after community acquired pneumonia has been ruled out. Treatment of AB is mainly symptomatic. Antibiotics should be used in immune-compromised hosts, patients with chronic respiratory or cardiac diseases and in the elderly with co-morbidities. Reactivation of COPD is defined as an acute change in the patient’s baseline clinical situation beyond normal day to day variations, with an increase in dyspnea, sputum production and/or sputum purulence, warranting a change in medication. An increase in one symptom is considered a mild exacerbation, two as moderate, and the presence of three symptoms is considered a severe exacerbation. An infectious agent can be isolated in sputum in 50 to 75

of COPD reactivations. Moderate and severe episodes must be treated with antibiotics, amoxicillin/ beta-lactamase inhibitor, macrolides and fluoroquinolones are first choice drugs.

Consenso sobre diagnóstico y tratamiento de infecciones de vías respiratorias altas / Consensus guidelines for the management of upper respiratory tract infections

Las infecciones respiratorias altas son la primera causa de prescripción de antibióticos. La faringitis aguda es de origen viral en la mayoría de los casos; los episodios virales pueden diferenciarse de los de origen bacteriano producidos por Streptococcus pyogenes por criterios clínico-epidemiológicos (criterios de Centor), por pruebas diagnósticas rápidas o por el cultivo de fauces. Cuando la etiología es estreptocócica, la droga de elección es penicilina V (cada 12 horas). La otitis media aguda (OMA) es una de las causas más frecuentes de prescripción de antibióticos en niños. Los patógenos principales son Streptococcus pneumoniae, Haemophilus influenzae no tipable y Moraxella catarrhalis. Los antecedentes, la evaluación clínica junto con la otoscopía permiten establecer el diagnóstico. En niños menores de 2 años se recomienda tratamiento antibiótico precoz al igual que en niños mayores de 2 años con otitis bilateral, otorrea, presencia de comorbilidad o cuadro clínico grave. En la Argentina, debido a los bajos niveles de resistencia de S. pneumoniae a penicilina la droga de elección es amoxicilina; ante falta de respuesta al tratamiento puede utilizarse amoxicilina/clavulánico para cubrir cepas de H. influenzae y de M. catarrhalis productoras de betalactamasas. Las rinosinusitis son virales en la mayoría de los casos y menos del 5% se complican con sinusitis bacteriana. El diagnóstico es clínico y en general no se requieren estudios complementarios. Los patógenos bacterianos implicados son los mismos que causan OMA, por esta razón también se recomienda la amoxicilina como droga de elección.

Upper respiratory tract infections are the most common source of antibiotic prescriptions. Acute pharyngitis is caused mainly by viruses, viral cases can be distinguished from acute streptococcal pharyngitis using Centor clinical epidemiological criteria, by rapid antigen tests or throat culture. Treatment of choice for streptococcal infection is penicillin V given in two daily doses. In children, acute otitis media (AOM) is the infection for which antibiotics are most often prescribed. Predominant causative pathogens include Streptococcus pneumoniae, Haemophilus influenzae non-type b and Moraxella catarrhalis. Diagnosis is based on history, physical examination and otoscopic exam. Antibiotic treatment should be initiated promptly in all children < 2 years of age, and in older children presenting bilateral AOM, otorrhoea, co-morbidities or severe illness. In Argentina, amoxicillin is the drug of choice given the low penicillin resistance rates for S. pneumoniae. In children who fail amoxicillin therapy, amoxicillin/clavulanate provides better coverage against beta-lactamase producing H. influenzae and M. catarrhalis. Rhinosinusitis is caused mainly by viruses, secondary bacterial complication occurs in less than 5% of cases. Diagnosis is based on physical examination and additional studies are not usually required. Acute bacterial sinusitis is caused by the same pathogens that cause AOM and amoxicillin is the drug of choice.

Neumonia adquirida en la comunidad. Guia practica elaborada por un comite intersociedades / Neumonía acquired in the community. Practical guide elaborated by a committee intersocieties

Clinical practice guidelines for community-acquired pneumonia (CAP) contribute to improve patient's management. CAP undergoes continuous changes in etiology, epidemiology and antimicrobial sensitivity, requiring periodic guidelines revisions. An inter-society committee designed this guidelines dividing it into several topics based on prior guidelines and recent clinical studies. CAP compromises annually more than 1 of the population; most of the cases only require outpatient care but others are severe cases, reaching the 6th cause of death in Argentina. The cases are distributed unevenly into ambulatory, admitted in the general ward or in the intensive care unit. There is no way to predict the etiology. Unfavorable outcome predictors include age, antecedents and physical, laboratory and radiography findings. Ten to 25 of inpatients need to be admitted to the intensive care unit at the onset or during the follow-up, for mechanical ventilation or hemodynamic support (severe CAP). Severe CAP is associated with high mortality and requires adequate and urgent therapy. Pregnant, COPD and nursing home patients require special recommendations. Diagnosis is clinical, while complementary methods are useful to define etiology and severity; chest X-ray is the only one universally recommended. Other studies, including microbiologic evaluation are particularly appropriate in the hospitalized patients. The initial therapy is empiric, it must begin early, using antimicrobials active against the target microorganisms, avoiding their inappropriate use which can lead to the development of resistance. Length of therapy must not be unnecessarily prolonged. Hydratation, nutrition, oxygen and therapy of complications must complement antibiotic treatment. Prevention is based on influenza prophylaxis, anti-pneumococcal vaccine, aspiration prevention and other general measures