description: 'Glomerular filtration rate (GFR) is considered the best overall index of kidney function;\nhowever measured GFR is not practical in the routine clinical setting. Estimated glomerular filtration rate\n(eGFR) is a suitable alternative and can be calculated for adults >= 18 years using an equation\nincorporating the patient''s age, gender, and measured serum/plasma/blood creatinine only (eGFRcr)\n(this term) or both serum/plasma/blood creatinine and serum/plasma cystatin C (eGFRcr-cys) [LOINC: 98980-6].\nThe serum/plasma/blood creatinine value is based on a measurement procedure that is traceable to the isotope\ndilution mass spectrometry (IDMS) reference measurement procedure for creatinine. The 2021 CKD-EPI equations\nused for eGFRcr and eGFRcr-cys do not have a race term as does the older estimating equations that they replace.\n[https://www.nejm.org/doi/pdf/10.1056/NEJMoa2102953]'
package_name: ch.fhir.ig.ch-lab-report
derivation: constraint
name: ChLabObservation_eGFRcr_cys_CKD_EPI_2021
type: Observation
elements:
  code:
    short: eGFRcr-cys SerPlBld CKD-EPI 2021
    mustSupport: true
    pattern:
      type: CodeableConcept
      value:
        coding:
        - {code: 98980-6, system: 'http://loinc.org', display: 'Glomerular filtration rate/1.73 sq M.predicted [Volume Rate/Area] in Serum, Plasma or Blood by Creatinine and Cystatin C-based formula (CKD-EPI 2021)'}
    index: 0
  referenceRange:
    array: true
    min: 1
    max: 3
    index: 1
    slicing:
      rules: open
      ordered: false
      description: Reference range by age
      discriminator:
      - {path: age.low.value, type: value}
      min: 1
      max: 3
      slices:
        child:
          match:
            age:
              low: {value: 0}
          schema:
            mustSupport: true
            index: 2
            elements:
              low:
                elements:
                  value:
                    pattern: {type: Decimal, value: 90}
                    index: 3
                  unit:
                    pattern: {type: String, value: mL/min}
                    index: 4
              age:
                elements:
                  low:
                    elements:
                      value:
                        pattern: {type: Decimal, value: 0}
                        index: 5
                      unit:
                        pattern: {type: String, value: a}
                        index: 6
                    required: [value]
                  high:
                    elements:
                      value:
                        pattern: {type: Decimal, value: 30}
                        index: 7
                      unit:
                        pattern: {type: String, value: a}
                        index: 8
              text:
                pattern: {type: String, value: Die Formel ist nur ab 18 Jahre validiert.}
                index: 9
        youth:
          match:
            age:
              low: {value: 18}
          schema:
            mustSupport: true
            index: 10
            elements:
              low:
                elements:
                  value:
                    pattern: {type: Decimal, value: 90}
                    index: 11
                  unit:
                    pattern: {type: String, value: mL/min}
                    index: 12
              age:
                elements:
                  low:
                    elements:
                      value:
                        pattern: {type: Decimal, value: 18}
                        index: 13
                      unit:
                        pattern: {type: String, value: a}
                        index: 14
                    required: [value]
                  high:
                    elements:
                      value:
                        pattern: {type: Decimal, value: 30}
                        index: 15
                      unit:
                        pattern: {type: String, value: a}
                        index: 16
              text:
                pattern: {type: String, value: Die Formel ist ab 18 bis 93 Jahre validiert.}
                index: 17
        adult:
          match:
            age:
              low: {value: 31}
          schema:
            mustSupport: true
            index: 18
            elements:
              low:
                elements:
                  value:
                    pattern: {type: Decimal, value: 60}
                    index: 19
                  unit:
                    pattern: {type: String, value: mL/min}
                    index: 20
              age:
                elements:
                  low:
                    elements:
                      value:
                        pattern: {type: Decimal, value: 31}
                        index: 21
                      unit:
                        pattern: {type: String, value: a}
                        index: 22
                    required: [value]
                  high:
                    elements:
                      value:
                        pattern: {type: Decimal, value: 100}
                        index: 23
                      unit:
                        pattern: {type: String, value: a}
                        index: 24
              text:
                pattern: {type: String, value: Die Formel ist nur bis 93 Jahre validiert.}
                index: 25
package_version: 1.0.0-ballot
class: profile
kind: resource
url: http://fhir.ch/ig/ch-lab-report/StructureDefinition/ch-lab-observation-egfr-cr-cys-ckd-epi-2021
base: http://fhir.ch/ig/ch-lab-report/StructureDefinition/ch-lab-observation-egfr
version: 1.0.0-ballot
required: [referenceRange]