Plasma and urinary adrenomedullin levels in children with renal parenchymal scar and vesicoureteral reflux

A Review of Adrenomedullin in Pediatric Patients: A Useful Biomarker

Adrenomedullin has several properties. It acts as a potent vasodilator, has natriuretic effects, and reduces endothelial permeability. It also plays a role in initiating the early hyperdynamic phase of sepsis. Since its discovery, many articles have been published studying the uses and benefits of this biomarker. The aim of this review is to determine the usefulness of adrenomedullin in pediatric patients. Relevant studies covering adrenomedullin in pediatrics (<18 years) and published up until August 2021 were identified through a search of MEDLINE, PubMed, Embase, Web of Science, Scopus, and Cochrane. Seventy studies were included in the present review, most of them with a low level of evidence (IV to VI). Research on adrenomedullin has primarily been related to infection and the cardiovascular field. The performance of adrenomedullin to quantify infection in children seems satisfactory, especially in sepsis. In congenital heart disease, this biomarker seems to be a useful indicator before, during, and after cardiopulmonary bypass. Adrenomedullin seems to be useful in the pediatric population for a large variety of pathologies, especially regarding infection and cardiovascular conditions. However, it should be used in combination with other biomarkers and clinical or analytical variables, rather than as a single tool.

Evaluation of renal function and scars in children with primary vesicoureteral reflux

OBJECTIVE

To evaluate growth, glomerular and tubular function, renal damage, scars in children affected by primary VUR.

METHOD

We retrospectively evaluated the clinical records of our Unit from January 2006 to September 2020. For each patient we evaluated growth, laboratoristic and scintigraphic glomerular and tubular function, renal damage and collective system urodynamics at baseline and at the last visit.

RESULT

We enrolled 41 patients affected by primary VUR and treated with continuous antibiotic prophylaxis. Glomerular function and urodynamics did not change over time. EFNa directly correlated with weight (r 0.44 p 0.004) and TRP inversely correlated with severity of reflux (r -0.32, p 0.04). Female sex was associated to nephrolithiasis (OR 17.0, p 0.02) and proteinuria (at T0 OR 5.8 p 0.03 at T1 OR 5.8, p 0.03). Daily proteinuria increased with age (r 0.66, p <0.0001 at T0 and r 0.44 p 0.004 at T1) while protein-to-creatinine ratio decreased. Renal scars at T0 inversely correlated with glomerular and tubular function at T1 but they did not correlate with severity or laterality of reflux.

CONCLUSION

Even if renal function remains stable through years, it is critical to identify the subjects with significant congenital renal damage.

MR-Proadrenomedullin as biomarker of renal damage in urinary tract infection in children

Background

Midregional-proadrenomedullin (MR-proADM) is a useful prognostic peptide in severe infectious pathologies in the adult population. However, there are no studies that analyze its utility in febrile urinary tract infection (fUTI) in children. An accurate biomarker would provide an early detection of patients with kidney damage, avoiding other invasive tests like renal scintigraphy scans. Our objective is to study the usefulness of MR-proADM as a biomarker of acute and chronic renal parenchymal damage in fUTI within the pediatric population.

Methods

A prospective cohort study was conducted in pediatric patients with fUTI between January 2015 and December 2018. Plasma and urine MR-proADM levels were measured at admission in addition to other laboratory parameters. After confirmation of fUTI, renal scintigraphy scans were performed during the acute and follow-up stages. A descriptive study has been carried out and sensitivity, specificity and ROC curves for MR-proADM, C-reactive protein, and procalcitonin were calculated.

Results

62 pediatric patients (34 female) were enrolled. Scintigraphy showed acute pyelonephritis in 35 patients (56.5%). Of those patients, the median of plasmatic MR-proADM (P-MR-proADM) showed no differences compared to patients without pyelonephritis. 7 patients (11.3%) developed renal scars (RS). Their median P-MR-proADM levels were 1.07 nmol/L (IQR 0.66–1.59), while in patients without RS were 0.48 nmol/L (0.43–0.63) (p < 0.01). The AUC in this case was 0.92 (95% CI 0.77–0.99). We established an optimal cut-off point at 0.66 nmol/L with sensitivity 83.3% and specificity 81.8%.

Conclusion

MR-ProADM has demonstrated a poor ability to diagnose pyelonephritis in pediatric patients with fUTI. However, P-MR-proADM proved to be a very reliable biomarker for RS prediction.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-02765-2.

Plasma and urinary adrenomedullin levels in children with acute pyelonephritis

AIM

Adrenomedullin (AM), a novel peptide recently isolated from pheochromocytoma, eliciting vasorelaxing activity, is the strongest among all known peptides. AM has been detected in the adrenal medulla, cardiac tissue, lung and kidney. Immunohistochemical studies have demonstrated the localization of AM in glomeruli, tubules and collecting cells of the kidney. Clinically, plasma and urinary AM levels are altered in patients with different renal disease. The present study aims to determine plasma and urinary AM levels in children with acute pyelonephritis (APN) and compare the results with a control group.

MATERIALS AND METHODS

The study group was comprised of 19 patients with APN aged 11.6 +/- 3.7 months (range, 6-18 months) and the control group consisted of 16 cases aged 11.5 +/- 3.2 months (range, 7-16 months). Acute pyelonephritis was diagnosed by clinical, laboratory and imaging methods. Plasma and urinary AM levels were measured by high performance liquid chromotography (HPLC).

RESULTS

The plasma AM levels were lower in APN patients (33.40 +/- 2.27 pmol/mL) than in the control group (43.76 +/- 4.27 pmol/mL) (P < 0.001), whereas the urinary AM levels were higher in APN patients (248.58 +/- 140.63 pmol/mg urinary creatinine) than in the control group (49.42 +/- 45.23 pmol/mg) (P < 0.001). Coefficients of correlation between urinary AM levels and C-reactive protein and white blood cells were statistically significant (r = 0.472, P = 0.041; r = 0.555, P = 0.014, respectively).

CONCLUSION

Adrenomedullin, a smooth muscle relaxant peptide that is synthesized in urinary tract tissue might have a role in acute pyelonephritis. However, the importance of AM in the pathogenesis of acute pyelonephritis remains to be determined by further detailed studies.