Resumen

MORIYON, Juan Carlos et al. Urinary tract infection: General aspects, pathogenesis and diagnosis. Arch Venez Puer Ped [online]. 2011, vol.74, n.1, pp.23-28. ISSN 0004-0649.

Urinary tract infection (UTI) is a clinical entity induced by invasion, colonization and multiplication of bacteria in the urinary tract which overpass de host defensive mechanisms, and could be the expression of functional or morphological disorders. UTI is a frequent cause of morbidity and affects 5 - 11% of pediatric patients and it is the first documented cause of pediatric nephrological consultation in Venezuela. The frequency of recurrence is 15-20% in children under 1 year of age after the first episode of UTI, and the risk is higher with previous episodes. Pathogenesis of UTI includes 3 related factors: the pathogenic germ, host and environment factors. Early detection of UTI and adequate study of the patient are important clues for the prevention of renal damage and prevention of progression to chronic renal disease. Important factors for the development of renal damage are: febrile UTI, anatomical or functional obstructive uropathy, vesicoureteral reflux with dilatation of the urinary tract, delay in the initiation of antibiotic treatment and presence of E. Coli. The diagnosis of UTI is based on clinical manifestations which vary with age and gender, and the presence or not of urological and/or neurological disorders. Alterations in the urine analysis could suggest UTI, but the definitive test for the diagnosis is de urine culture, which should be performed previously to antibiotic therapy; etiological diagnosis is made by the presence of significative growth of bacteria in the urine. The less invasive method to collect the urine sample is the clean catch with previous perineal asepsis. The number of colonies/ml required to consider a urine culture as positive vary according with the sample collection method.

Palabras clave : Urinary tract infection; uropathies; vesico ureteral reflux; urine test; urine culture.