Cystatin C, but not urinary or serum NGAL, may be associated with contrast induced nephropathy after percutaneous coronary invasive procedures: A single center experience on a limited number of patients.

OBJECTIVE: This study aimed to test the association of both the baseline values and post-procedural variations of urinary and serum Neutrophil Gelatinase-Associated Lipocalin (NGAL) and Cystatin C (CysC) with contrast induced nephropathy (CIN) occurrence in patients undergoing percutaneous coronary invasive procedures (PCIP), and compare them to serum creatinine and the estimated glomerular filtration rate (eGFR). METHODS: In 43 patients admitted to our Cardiac Step-Down Unit and submitted to PCIP, we measured serum creatinine and eGFR as the standard markers for CIN diagnosis, and compared them to both serum and urinary NGAL as well as serum CysC, assessed before and 4 hours after PCIP. RESULTS: Patients who developed CIN (16%) were older, with significantly higher discharge creatinine values, lower eGFR values at creatinine peak, and higher baseline and post-PCIP CysC values. We did not detect any significant association between baseline serum and urinary NGAL values and their 4 hour variations after contrast medium administration and CIN occurrence. Furthermore, we observed that the baseline values of both serum and urinary NGAL were significantly higher in patients with greater neutrophil count. CONCLUSION: In our population submitted to PCIP, neither baseline serum and urinary NGAL nor their variations after PCIP were related to CIN occurrence, while CysC results were associated with CIN development, earlier than creatinine and eGFR variations.

Expression and characterization of anionic components in the tubulointerstitial compartment of rat kidney during polymicrobial sepsis.

The aim of the study was to evaluate sialic acids and hyaluronan expression, anionic components important for the structure and function of the renal tubulointerstitial compartment, in the early stages of sepsis. Two groups of rats were used: (1) sham-operated controls; (2) cecal ligation and puncture (CLP) (polymicrobial sepsis model). A search for microbial growth was made in the peritoneal fluid to document infection. Tubular function was evaluated by means of urinary protein loss, urinary Na(+) and urea excretion. Kidney samples were processed to analyze histology, sialic acids (lectin histochemistry) and hyaluronan (immunohistochemistry) expression. Results showed increased urinary protein loss and fractional excretion of Na(+) and urea reduction in the CLP group. Histological changes, particularly in the cortex and in proximal tubules of the CLP group, were observed. In septic rats, compared to controls, sialic acids decreased in amount and their acetylation increased in the tubules, although to a lesser extent in the proximal portion. Hyaluronan was expressed in the medullary interstitium and in a few areas of cortex in controls. In septic rats it increased in the cortical interstitium and appeared in proximal tubules. These results suggest correlation between expression changes of anionic components and tubulointerstitium morphofunctional alterations during sepsis. A role of these molecules in protection/defense and repair processes may be suggested.