Hiponatremia e hipofosforemia en las neumonías: ¿qué papel desempeña el riñón? / Hyponatremia and hypophosphatemia in pneumonia: what role does the kidney?

Antecedentes: La hiponatremia es una alteración electrolítica relativamente frecuente en pacientes con neumonía, cuya patogenia se relaciona con el síndrome de secreción inapropiada de hormona antidiurética. El objetivo de este estudio era describir las alteraciones hidroelectrolíticas y hormonales en niños, previamente sanos, diagnosticados de neumonía adquirida en la comunidad (NAC), y compararlas con las de los niños sanos. Material y métodos: Se llevó a cabo un estudio de casos y controles. El grupo de casos (n= 25) estuvo formado por pacientes diagnosticados de NAC según criterios de la Organización Mundial de la Salud, con una media de edad de 4,2 ± 2,4 años; ninguno había recibido fluidoterapia intravenosa. En el grupo control (n= 27) se incluyeron niños sanos, con una media de edad de 5 ± 2,6 años, autorizados a participar en el estudio. Se realizó un análisis bioquímico en sangre y en orina (en micción aislada). En el grupo de NAC se determinaron las cifras de proteína C reactiva (PCR), procalcitonina (PCT) y vasopresina (ADH). Resultados: Los valores medios séricos del sodio, aunque en rango normal, fueron significativamente menores en el grupo de casos que en el grupo control, al igual que la excreción fraccional de sodio (EFNa), cuyo valor medio fue significativamente menor que el del grupo control. No hubo relación entre la natremia, la EFNa y los niveles de ADH. Se encontró una relación significativamente negativa entre los valores de sodio y la temperatura axilar (r= -0,64; p <0,001), la PCR (r= -0,41; p <0,04) y el recuento de leucocitos (r= -0,43; p <0,01) en sangre periférica. El valor medio del fósforo sérico era significativamente inferior al del grupo control. Se encontró una relación significativa entre la fosforemia y la reabsorción tubular de fosfato, expresada mediante TP/GFR (r= 0,97; p <0,001), y la PCR (r= -0,4; p <0,04). Conclusiones: En esta serie, los pacientes con NAC muestran una clara tendencia a presentar un descenso de la natremia. Esta tendencia es de causa extrarrenal y se relaciona significativamente con el proceso inflamatorio secundario a la infección. El descenso del fósforo sanguíneo también se relaciona con la infección, y es secundaria a una pérdida excesiva de fósforo por el riñón (AU)

Introduction: Hyponatremia is a relatively common electrolyte disturbance in patients with pneumonia and its pathogenesis has been related with the syndrome of inappropriate secretion of antidiuretic hormone. The aim of this study was to describe the electrolyte and hormonal abnormalities in children diagnosed with community-acquired pneumonia (CAP) and compare them with those obtained in healthy children. Material and methods: This is a case-control study. In the case group we included patients with CAP (n= 25), according to WHO criteria. None of the patients has received intravenous fluids. The control group (n= 27) included healthy children without disease. Biochemical blood and urine (isolated urination) were determined as analytical tests. In the CAP group C-reactive protein (CRP), procalcitonin (PCT) and levels of vasopressin (ADH) were determined. Results: The serum sodium mean values and the fractional excretion of sodium (FENa) were significantly lower in the case group than in the control group, although they were both in the normal range. There was no relationship between serum sodium, FENa and ADH levels. A significantly negative relationship was found between sodium and axillary temperature (r= -0.64; p <0.001), CRP (r= -0.41; p <0.04) and the leukocyte count in peripheral blood (r= -0.43; p <0.01). The mean serum phosphorus level was significantly lower in the case group. A remarkable relationship between phosphoremia and tubular phosphate reabsorption, expressed by TP/GFR (r= 0.97; p <0.001), and CRP (r= -0.4; p <0.04) was found. Conclusions: In this series, cases with CAP show a clear tendency of decreased serum sodium. This trend has an extrarenal cause and it is significantly related to the inflammatory process secondary to the infection. Hypophosphoremia also relates to infection and is secondary to excessive loss of phosphorus by the kidney (AU)

Human parechoviruses in infants with systemic infection.

Human parechoviruses (HPeVs) are RNA viruses related to neonatal sepsis, meningoencephalitis and other infections in young children. Little clinical and epidemiological information is available on these viruses. HPeVs were sought in cerebrospinal fluid from 397 infants aged less than 12 months from whom a sample was obtained to exclude meningitis or encephalitis from 2006 to 2009. HPeV infections were also tested in stool samples from 271 children aged less than 3 years old with gastroenteritis from November 2008 to March 2009. HPeV detection was by real-time polymerase chain reaction assay (region 5'UTR), followed by genotyping (region VP3/VP1). HPeVs were detected in the cerebrospinal fluid of nine infants (2.3%), one aged 6 months and eight aged 14-55 days old. All were admitted to hospital for febrile syndrome with abrupt clinical deterioration and suspected systemic infection without clear laboratory signs of meningeal inflammation. The same virus was detected in all the available nasopharyngeal aspirates, stool, and/or serum samples from each patient. At least eight of the nine cases were caused by HPeV3. HPeVs were detected in stool samples from 17 children (6.3%), the most prevalent types being types 1 and 3. In conclusion, HPeV infection is common in the Basque Country (Spain) and HPeV3 is a significant cause of hospital admission due to systemic infection in the first few months of life. In these patients, HPeVs should be investigated as part of routine tests for enterovirus.