[Hereditary stomatocytoses--diagnostic problems and their molecular basis].

Hereditary stomatocytosis (HSt) is a group of haemolytic anaemias in which the common symptom is an increased permeability of the red cell membrane for monovalent cations. HSt is diagnosed really seldom and the difficulties in diagnosing are connected to the fact that the clinical presentation of individual subtypes of HSt is very diverse. Many cases are characterised by unique phenotypes. Nevertheless, the number of diagnosed HSt cases is increasing each year. The aim of this review was the presentation of current information and an attempt to systematize it, what might be helpful in clinical diagnostic of the new cases of this anaemia. The most frequent mistake is to classify a case of HSt as the most common haemolytic anaemia--hereditary spherocytosis (HS), in which to improve patient condition a splenectomy is often recommended. Most cases of HSt no positive response to splenectomy and often thromboembolic complications are observed. It is interesting that commonly present in blood film stomatocytes and in many cases absent or severely reduced stomatin in HSt red cell membrane are not correlated with nucleotide sequence changes of the gene encoding stomatin. Many diagnosed cases are related to mutations in SLC4A1 and RHAG genes. Extensive research carried out on HSt in the entire world will certainly permit to know the molecular basis of the disease, the diversify of its subtypes and to estimate the real incidence of HSt.