Hereditary stomatocytosis

Infobox_Disease
Name = Hereditary stomatocytosis


Caption =
DiseasesDB = 29710
ICD10 = ICD10|D|58|8|d|55
ICD9 = ICD9|282.8
ICDO =
OMIM = 185000
OMIM_mult = OMIM2|185010
MedlinePlus =
eMedicineSubj =
eMedicineTopic =

Hereditary stomatocytosis describes a number of inherited autosomal dominant human conditions which affect the red blood cell, in which the membrane or outer coating of the cell 'leaks' sodium and potassium ions.

Pathophysiology

Osmosis leads to the red blood cell having a constant tendency to swell and burst. This tendency is countered by manipulating the flow of sodium and potassium ions. A 'pump' forces sodium out of the cell and potassium in, and this action is balanced by a process called 'the passive leak'. In the hereditary stomatocytoses, the passive leak is increased and the cell becomes swamped with salt and water. The cell lyses and a haemolytic anaemia results. For as yet unknown reasons, the cells take on an abnormal shape, resembling a mouth or 'stoma'.

Variants

Haematologists have identified a number of variants. These can be classified as below.

*Overhydrated hereditary stomatocytosis
*Dehydrated HSt (hereditary xerocytosis; hereditary hyperphosphatidylcholine haemolytic anaemia)
*Dehydrated with perinatal ascites
*Cryohydrocytosis
*'Blackburn' variant.
*Familial pseudohyperkalaemia

There are other families that do not fall neatly into any of these classifications. [cite journal |author=Oski FA, Naiman JL, Blum SF, "et al" |title=Congenital hemolytic anemia with high-sodium, low-potassium red cells. Studies of three generations of a family with a new variant |journal=N. Engl. J. Med. |volume=280 |issue=17 |pages=909–16 |year=1969 |pmid=4237839 |doi= |url=]

Treatment

At present there is no specific treatment. Many patients with haemolytic anaemia take folic acid (vitamin B9) since the greater turnover of cells consumes this vitamin. During crises transfusion may be required. Clotting problems can occur for which anticoagulation may needed.

Causes

The cause for these hereditary conditions is now understood to be various mutations in the erythrocyte membrane protein, band 3. It is this protein which mediates the cation leaks which are characteristic of this disease.cite journal |author=Bruce LJ, Robinson HC, Guizouarn H, "et al" |title=Monovalent cation leaks in human red cells caused by single amino-acid substitutions in the transport domain of the band 3 chloride-bicarbonate exchanger, AE1 |journal=Nat. Genet. |volume=37 |issue=11 |pages=1258–63 |year=2005 |pmid=16227998 |doi=10.1038/ng1656]

References

*cite journal |author=Eber SW, Lande WM, Iarocci TA, "et al" |title=Hereditary stomatocytosis: consistent association with an integral membrane protein deficiency |journal=Br. J. Haematol. |volume=72 |issue=3 |pages=452–5 |year=1989 |pmid=2765409 |doi= |url=

*cite journal |author=Hiebl-Dirschmied CM, Adolf GR, Prohaska R |title=Isolation and partial characterization of the human erythrocyte band 7 integral membrane protein |journal=Biochim. Biophys. Acta |volume=1065 |issue=2 |pages=195–202 |year=1991 |pmid=1711899 |doi= |url=http://linkinghub.elsevier.com/retrieve/pii/0005-2736(91)90230-6

*cite journal |author=Hiebl-Dirschmied CM, Entler B, Glotzmann C, Maurer-Fogy I, Stratowa C, Prohaska R |title=Cloning and nucleotide sequence of cDNA encoding human erythrocyte band 7 integral membrane protein |journal=Biochim. Biophys. Acta |volume=1090 |issue=1 |pages=123–4 |year=1991 |pmid=1883838 |doi= |url=http://linkinghub.elsevier.com/retrieve/pii/0167-4781(91)90047-P

*cite journal |author=Stewart GW, Hepworth-Jones BE, Keen JN, Dash BC, Argent AC, Casimir CM |title=Isolation of cDNA coding for an ubiquitous membrane protein deficient in high Na+, low K+ stomatocytic erythrocytes |journal=Blood |volume=79 |issue=6 |pages=1593–601 |year=1992 |pmid=1547348 |doi= |url=http://www.bloodjournal.org/cgi/pmidlookup?view=long&pmid=1547348