Twin cases of hereditary spherocytosis: A tale of missed diagnoses

Abstract

Hereditary spherocytosis (HS) is one of the most common hereditary haemolytic anaemia (HA) with variable clinical expression of anaemia, splenomegaly and presence of spherical cells called spherocytes due to the presence of mutations in rbcs membrane protein genes e.g. ANK1 (ankyrin), EPB42 (protein 4.2), SPTA1(α-spectrin), SPTB (β-spectrin) and SLC4A1 (Band 3). There is autosomal dominant inheritance in 75% cases and autosomal recessive in 25% cases. We report a pair of case of mother and male child; their samples for hemogram were simultaneously received in haematology laboratory. .Both the blood samples showed features of HA with the presence of spherocytes which was confirmed by bed side smear preparation. The value of mean corpuscular haemoglobin concentration (MCHC) was non-contributory to the diagnosis of HS. The bed side smear preparation from finger prick is advantageous as it circumvents the changes due to EDTA excess especially in severely anaemic patients; also the blood cell morphology is better preserved. The advantage of this technique is that there is no time lag between the draw of sample and transit to laboratory, hence no degeneration of blood sample. The study includes review of literature for Red cell indices and Peripheral Blood film (PBF) examination for usage in diagnosis of HS and the current diagnostic protocol for HS.