title: Cystatin C: A Marker for Inflammation and Renal Function Among HIV-infected Children and Adolescents.
abstract: BACKGROUND
  Renal disease is a leading cause of morbidity in HIV-infected adults in the highly active antiretroviral therapy (HAART) era. Cystatin C has been proposed as a more sensitive marker of renal function, but it may be affected by ongoing inflammation. We aimed to study the cystatin C levels in a cohort of HIV-infected pediatric patients at 3 Spanish centers.
  
  
  METHODS
  This is a multicenter cross-sectional observational study. Renal function was assessed by means of first morning urine protein/creatinine and albumin/creatinine ratios and creatinine-estimated glomerular filtration rates (GFRs), together with the following inflammation markers: cystatin C, reactive C protein, β-2-microglobulin and 25(OH)-vitamin D levels. A control group of healthy children and adolescents was used.
  
  
  RESULTS
  Eighty-three patients (51 females, median age: 13.3 years; 32 males, median age: 13.6 years) and 44 controls (24 females, median age: 12.2 years; 20 males, median age: 10.9 years) were included. Among the former, mean CD4 cell count was 860/mm, 29(35%) patients had a previous AIDS diagnosis, 73(88%) were on HAART and HIV viremia was undetectable in 61(73%). No differences in cystatin C levels were observed between the 2 groups. In HIV-infected patients, cystatin C levels correlated with GFR (r = -0.27; P = 0.01), age at first HAART (r = -0.21; P = 0.05), and β-2-microglobulin (r = 0.569; P < 0.01). In multivariate analysis, lower GFR (P = 0.014) and higher β-2-microglobulin levels (P = 0.001) remained as independent risk factors for higher cystatin C values.
  
  
  CONCLUSIONS
  Cystatin C values were associated with GFR and β-2-microglobulin. Cystatin C may be useful as a marker of renal function in HIV-infected pediatric patients, independently of ongoing inflammation or viremia.
authors.affiliation: From the *Infectious Diseases Unit, Pediatrics Department, Hospital Sant Joan de Déu, Universitat de Barcelona, Barcelona, Spain; †Pediatric Infectious Diseases and Immunodeficiencies Unit, Hospital Universitari Vall d'Hebron, Institut de Recerca Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain; ‡Unidad de Enfermedades Infecciosas e Inmunopatologias, Hospital Infantil Virgen del Rocio, Instituto de Biomedicina de Sevilla, Sevilla, Spain; §Blanquerna School of Health Science, Universitat Ramon Llull, Barcelona, Spain; and ¶Nephrology Department and ‖Laboratory Department, Hospital Sant Joan de Déu, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Àngela
authors.initials: À
authors.lastname: Deyà-Martínez
authors.forename: Clàudia
authors.initials: C
authors.lastname: Fortuny
authors.forename: Pere
authors.initials: P
authors.lastname: Soler-Palacín
authors.forename: Olaf
authors.initials: O
authors.lastname: Neth
authors.forename: Emília
authors.initials: E
authors.lastname: Sánchez
authors.forename: Andrea
authors.initials: A
authors.lastname: Martín-Nalda
authors.forename: Lola
authors.initials: L
authors.lastname: Falcón-Neyra
authors.forename: Anna
authors.initials: A
authors.lastname: Vila
authors.forename: Anna
authors.initials: A
authors.lastname: Valls
authors.forename: Antoni
authors.initials: A
authors.lastname: Noguera-Julian
mesh_terms: D000293:Adolescent; D015415:Biomarkers / Q000097:blood*; D002648:Child; D003430:Cross-Sectional Studies; D055316:Cystatin C / Q000097:blood*; D005260:Female; D015658:HIV Infections / Q000150:complications* / Q000473:pathology*; D006801:Humans; D007249:Inflammation / Q000473:pathology*; D007674:Kidney Diseases / Q000175:diagnosis*; D007677:Kidney Function Tests; D008297:Male; D013030:Spain; D001613:beta 2-Microglobulin / Q000097:blood
chemical_list: D015415:Biomarkers; D055316:Cystatin C; D001613:beta 2-Microglobulin