title: Role of glycated hemoglobin in the screening and diagnosis of posttransplantation diabetes mellitus after renal transplantation: A diagnostic accuracy study.
abstract: BACKGROUND
  The role of glycated hemoglobin (A1C) in the screening and diagnosis of posttransplantation diabetes mellitus (PTDM) is still not entirely understood. We evaluated the use of A1C test in renal transplant recipients at four months after transplantation.
  
  
  METHODS
  A total of 122 out of 274 patients without previous diabetes that underwent kidney transplantation were enrolled. ROC curve was used to analyze the performance of A1C to diagnose PTDM considering OGTT as the reference standard.
  
  
  RESULTS
  OGTT identified 32 (26.2%) patients with PTDM, whereas A1C≥6.5% (48 mmol/mol) identified only 16 patients. A1C showed moderate accuracy to detect PTDM in the ROC curve [AUC 0.832 (95% CI 0.740-0.924, p<0.001)]. A1C of 5.8% (40 mmol/mol) was the equilibrium point (sensitivity 75% and specificity 72.2%) and A1C≥6.2% (44 mmol/mol) showed high specificity of 93.3%.
  
  
  CONCLUSIONS
  A1C≥6.5% (48 mmol/mol) is not enough to be used alone in the diagnosis of PTDM. The combined use of A1C cut-off points of ≤5.8% (40 mmol/mol) and ≥6.2% (44 mmol/mol) would reduce the number of OGTT by 85%. The use of an algorithm with A1C test in combination with FPG and/or 2h-PG proved to be the most efficient strategy to diagnose or rule out PTDM.
authors: Graduate Program in Endocrinology, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
authors: Ana Laura
authors: AL
authors: Pimentel
authors: Nursing School, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
authors: Larissa Sant Anna Kellermann
authors: LS
authors: Carvalho
authors: Nursing School, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
authors: Samara Silva
authors: SS
authors: Marques
authors: Division of Nephrology, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.
authors: Rodrigo Fontanive
authors: RF
authors: Franco
authors: Graduate Program in Endocrinology, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil; Division of Endocrinology, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.
authors: Sandra Pinho
authors: SP
authors: Silveiro
authors: Division of Nephrology, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.
authors: Roberto Ceratti
authors: RC
authors: Manfro
authors: Graduate Program in Endocrinology, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil; Division of Endocrinology, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil. Electronic address: jcamargo@hcpa.ufrgs.br.
authors: Joíza Lins
authors: JL
authors: Camargo
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism*; D003430:Cross-Sectional Studies; D003920:Diabetes Mellitus / Q000097:blood* / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology; D005260:Female; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D007668:Kidney / Q000378:metabolism / Q000473:pathology; D016030:Kidney Transplantation / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D012372:ROC Curve
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human
keywords: A1C; Diagnostic accuracy; Glycated hemoglobin; PTDM; Posttransplantation diabetes mellitus; Renal transplantation