title: Serum cystatin C levels in preterm newborns in our setting: Correlation with serum creatinine and preterm pathologies.
abstract: BACKGROUND
  Cystatin C (CysC) is a renal function marker that is not as influenced as creatinine (Cr) by endogenous or exogenous agents, so it is therefore proposed as a marker in preterm infants.
  
  
  OBJECTIVE
  To determine serum CysC values in preterm infants during the first week of life, compared to Cr. To analyze alterations caused by prematurity diseases.
  
  
  METHODS
  The design involved a longitudinal, observational study of prospective cohorts. Groups were based on gestational age (GA): Group A (24-27 weeks), Group B (28-33 weeks), Group C (34-36 weeks). Blood samples were collected at birth, within 48-72hours and after 7 days of life.
  
  
  METHODS
  SPSS v.20 software was used. The statistical methods applied included chi-squared test and ANOVA.
  
  
  RESULTS
  A total of 109 preterm infants were included in the study. CysC levels were: 1.54mg/L (±0.28) at birth; 1.38mg/L (±0.36) within 48-72hours of life; 1.50mg/L (±0.31) after 7 days (p<0.05). Cr levels were: 0.64mg/dL (±0.17) at birth; 0.64mg/dL (±0.28) within 48-72hours; 0.56mg/dL (±0.19) after 7 days (P<.05). CysC values were lower in hypotensive patients and those with a respiratory disease (P<.05), and no alterations associated with other diseases were observed. There were no differences in Cr levels associated with any disease. Creatinine levels were higher in patients ≤1.500g (P<.05).
  
  
  CONCLUSIONS
  Serum CysC decreased within 48-72hours of life, and this decline showed significance (P<.05). The levels increased after 7 days in all 3 GA groups, and there was no difference in CysC levels among the groups. More studies in preterm infants with hypotension and respiratory disease are required. CysC is a better glomerular filtration (GF) marker in ≤1.500g preterm infants.
authors: UGC Neonatología, Hospital Universitario Virgen Macarena, Sevilla, España.
authors: Leonor
authors: L
authors: Bardallo Cruzado
authors: Unidad de Nefrología Pediátrica, UGC de Pediatría, Hospital Universitario Virgen Macarena, Sevilla, España. Electronic address: pg.elena@gmail.com.
authors: Elena
authors: E
authors: Pérez González
authors: UGC de Pediatría, Hospital Universitario Virgen Macarena, Sevilla, España.
authors: Zoraima
authors: Z
authors: Martínez Martos
authors: UGC Bioquímica Clínica, Hospital Universitario Virgen Macarena, Sevilla, España.
authors: Carmen
authors: C
authors: Bermudo Guitarte
authors: UGC Neonatología, Hospital Universitario Virgen Macarena, Sevilla, España.
authors: Mercedes
authors: M
authors: Granero Asencio
authors: UGC Neonatología, Hospital Universitario Virgen Macarena, Sevilla, España.
authors: Salud
authors: S
authors: Luna Lagares
authors: Unidad de Nefrología Pediátrica, UGC de Pediatría, Hospital Universitario Virgen Macarena, Sevilla, España.
authors: Mariano
authors: M
authors: Marín Patón
authors: Departamento de Bioestadística, Universidad de Sevilla, Sevilla, España.
authors: Juan
authors: J
authors: Polo Padilla
mesh_terms: D015415:Biomarkers / Q000097:blood; D001835:Body Weight; D003404:Creatinine / Q000097:blood*; D055316:Cystatin C / Q000097:blood*; D005260:Female; D005865:Gestational Age; D005919:Glomerular Filtration Rate; D006801:Humans; D007022:Hypotension / Q000097:blood; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000097:blood*; D007674:Kidney Diseases / Q000097:blood* / Q000151:congenital; D008297:Male; D011446:Prospective Studies; D012120:Respiration Disorders / Q000097:blood; D013997:Time Factors
chemical_list: D015415:Biomarkers; C525030:CST3 protein, human; D055316:Cystatin C; D003404:Creatinine
keywords: Cistatina C; Creatinina; Creatinine; Cystatin C; Premature infant; Pretérmino