Test Background Reticulocytes are young red cells newly released from the bone marrow. The reticulocyte count gives an indication of bone marrow activity, and is often integral in the classification and assessment of anaemias.
In reticulocytes, the nucleus has been extruded but ribosomal RNA is still present for the first 1 to 2 days in the peripheral circulation. Supravital staining is used to identify reticulocytes, which can then be enumerated.
Clinical Indications An increased reticulocyte count may be seen in chronic anaemia states, haemolytic anaemias and bleeding. A decreased reticulocyte number is observed in iron deficiency anaemia, pernicious anaemia or folate deficiency, aplastic anaemia, radiation therapy and other causes of bone marrow failure, eg. secondary to infection or cancer.
Reference Range 20-92 x 109/L
Sample Required 4 mL EDTA (lavender top) adults
0.5 mL EDTA (lavender top) paediatrics
Sample Volume 0.5 mL adult tube
0.2 mL paediatric tube