Renal Anemia: Test and Diagnosis

1st order laboratory parameters – obligatory laboratory tests.

• Small blood count [normocytic normochromic anemia:
  • MCV normal → normocytic
  • MCH normal → normochromic]

  Hb progression controls are useful no earlier than 2 weeks after changing an ESA(“erythropoiesis-stimulating agents”) dose.

• Differential blood count
• Inflammatory parameters – CRP (C-reactive protein) or ESR (erythrocyte sedimentation rate).
• Micronutrients:
  • Iron
  • Ferritin (iron storage protein)
    • Iron deficiency depending on renal function: normal renal function: ferritin < 30 ng/ml; predialysis: ferritin < 100 ng/ml; CKD (“chronic kidney disease”) 5D: < 200 ng/ml.
    • If serum ferritin level > 500 ng/ml, further iron administration must be carefully considered.
    • Normal or elevated ferritin levels + decreased TSAT (transferrin saturation; < 20%) = functional Fe deficiency (iron deficiency).
  • Folic acid
  • Vitamin B12
• Reticulocytes (“young erythrocytes”) [reticulocyte count normal to ↓]
• Urine status (rapid test for: nitrite, protein, hemoglobin, erythrocytes, leukocytes) incl. sediment, if necessary urine culture (pathogen detection and resistogram, that is, testing of suitable antibiotics for sensitivity / resistance).
• Renal parameters – urea, creatinine, if necessary cystatin C or creatinine clearance.
• Erythropoietin (synonyms: erythropoietin, EPO) – ↓ in renal anemia (because of diurnal fluctuations blood collection in the morning: 08.00 clock – 10.00 clock).
  • EPO is further decreased in:
    • AIDS
    • Tumor anemia
    • Polycythaemia vera

Laboratory parameters 2nd order – depending on the results of the history, physical examination, etc. – for differential diagnostic clarification.

• Transferrin (iron transport protein)/transferrin saturation (TSAT).
• Soluble transferrin receptor
• Haptoglobin – due todiagnosis and progression of hemolytic diseases.
• Test for occult (not visible) blood in the stool.
• Zinc protoporphyrin – is present in excessive levels in iron deficiency.
• Liver parameters – alanine aminotransferase (ALT, GPT), aspartate aminotransferase (AST, GOT), glutamate dehydrogenase (GLDH), gamma-glutamyl transferase (γ-GT, gamma-GT; GGT), alkaline phosphatase, bilirubin.
• Thyroid parameters – TSH (thyroid-stimulating hormone).
• Bone marrow biopsy