Corrected Reticulocyte Count / Reticulocyte Production Index
Corrects the reticulocyte percentage for the degree of anaemia. The Reticulocyte Production Index (RPI) determines if the bone marrow response is adequate, distinguishing hypoproliferative from haemolytic anaemia.
Score interpretation
Reticulocyte Production Index < 2: Bone marrow response inadequate for degree of anaemia.
→ Investigate for: iron deficiency, B12/folate deficiency, anaemia of chronic disease, aplastic anaemia, bone marrow failure, renal anaemia (erythropoietin deficiency). Haematology review if unexplained.
Borderline marrow response.
→ Monitor. Reticulocyte response may be building. Recheck FBC in 1–2 weeks. Treat deficiencies if identified.
RPI ≥ 3: Adequate bone marrow response. Suggests peripheral destruction or loss.
→ Consider: haemolytic anaemia (check LDH, bilirubin, haptoglobin, blood film), acute blood loss. Investigate haemolysis cause (direct Coombs, ADAMTS13, peripheral smear for schistocytes).
Interpretation bands for the Reticulocyte Index. Apply clinical judgement and local guidance.
References
- Hillman RS, Finch CA. Red Cell Manual. 7th ed. FA Davis, 1996.
Related
Curated clinical cross-links plus same-class fallbacks.
- Ferric Carboxymaltose (IV Iron — Pregnancy) · IV Iron Preparation — Iron Deficiency Anaemia in Pregnancy
- Iron Supplementation (Paediatric) · Iron Supplement — Iron Deficiency Anaemia in Children
- Ferric Carboxymaltose · IV Iron — Anaemia
- Iron Sucrose · IV Iron — Anaemia
- Thiamine (IV/IM — Pabrinex) · Vitamin B1 (Thiamine) — deficiency treatment / Wernicke's encephalopathy prevention
- Ferrous Sulphate · Iron Supplement (Oral)
- Major Haemorrhage / Massive Transfusion · BCSH; RCOA; RCEM; RCS — BCSH Guidelines
- Anaemia Investigation · BSH / NICE
- Splenomegaly Workup · BSH; BMJ Best Practice
- Deep Vein Thrombosis Diagnosis and Treatment · NICE CG144 / NICE NG158
- Sickle Cell Crisis · BSH 2021 / BCSH
- Neutropenic Sepsis · NICE CG151 2012 / ESMO
Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.