[Predictive markers of acute focal bacterial nephritis. A multicentre case-control study]. / Marcadores predictivos de nefritis focal bacteriana aguda. Estudio multicéntrico casos-control.

INTRODUCTION: Acute focal bacterial nephritis is an interstitial bacterial infection, localised in the renal parenchyma, which can be more serious than acute pyelonephritis. The aim of this study is the analysis of predictive factors that may lead to its early diagnosis, which is essential for an adequate therapeutic approach. PATIENTS AND METHODS: A retrospective, multicentre case and control study. The participant centres were hospitals in Castellon and Valencia. The study period was 2010-2018, with the cases being patients with focal bacterial nephritis and the patients with pyelonephritis as controls. RESULTS: A total of 158 (1:1) patients were included. The median age of the cases was 2 years and there were 75% females. There were no differences in the clinical presentation. In the univariate analysis, focal nephritis was associated with malformations of the urinary tract, bacteraemia, the neutrophil count, and procalcitonin, as well as febrile convulsions of borderline significance. Procalcitonin values ≥2 ng/ml had an OR of 4.9 (95%CI; 1.77-13.85) of presenting with focal nephritis. In the multivariate analysis, the urological malformations still maintained statistical significance and borderline significance for procalcitonin. CONCLUSIONS: The urinary tract malformations predispose the development of focal bacterial nephritis. In patients with a urinary tract infection and predictive factors of acute focal bacterial nephritis it would be worthwhile performing a renal Doppler ultrasound in the acute phase for its appropriate diagnosis and treatment.

Nefronia en pediatría: dentro del espectro de las infecciones urinarias. Serie clínica y revisión de la literatura / Nephronia in pediatrics: part of the spectrum of upper urinary tract infections. Clinical cases and review of the literature

Nephronia or focal acute nephritis corresponds to a localized inflammatory non-liquefactive kidney infection which may involve parenchyma of one or more renal lobes. It has been suggested that nephronia is part of the spectrum of upper urinary tract infections between acute pyelonephritis and renal abscess. It is associated with a prolonged clinical course, higher levels of inflammatory markers and an increased risk of renal scarring, compared to pyelonephritis. Ultrasound plays a useful role. Nephronia is an under-diagnosed condition, thus, clinical suspicion is important for early diagnosis and appropriate treatment. We present three paediatric cases, and a review of the literature.

La nefronia o nefritis focal aguda es una inflamación renal de etiología bacteriana sin licuefacción que típicamente involucra el parénquima de uno o más lóbulos renales. Dentro del espectro de las infecciones del tracto urinario, se ha planteado que podría ser una entidad intermedia entre la pielonefritis aguda y el absceso renal. Se asocia a un curso clínico más prolongado, mayores marcadores inflamatorios y mayor riesgo de cicatrices renales, al compararla con la pielonefritis. La ecografía renal juega un rol útil en el diagnóstico. Es una entidad subdiagnosticada; por lo que su sospecha es relevante para un diagnóstico oportuno y un tratamiento adecuado. Se presentan tres casos clínicos pediátricos y una revisión del tema.