Issues Affecting the Blood / Bone Marrow
Hematological issues are described in mitochondrial disease and include issues with bruising and bleeding, thrombotic stroke, anemia, and pancytopenia. The actual mechanisms are not well understood.
Bruising
A significant amount of ATP is required for each phase of platelet function, including shape change, aggregation and release reaction. Impairment of ATP production can impact platelet function (Kotzailias, 2004). A decrease in platelet function was noted during and following exercise but was not thought to be a primary factor in the etiology of stroke (Kotzailias, 2004).
For patients with easy bruising, vitamin E supplementation may exacerbate the symptom.
Stroke
In MELAS syndrome there may be a significant load of abnormal mitochondria in the endothelial cells and smooth muscles cells of pial arterioles and small intracerebral arteries (Sakuta, 1989; Koga, 2006), impacting blood vessel contraction and dilatation and impairing the microcirculation of the brain leading to ischemia and stroke (Koga, 2006).
Stroke-like episodes manifest the same symptoms as traditional stroke but are not due to problems in the distribution of major cerebral blood vessels (see ACUTE NEUROLOGICAL DETERIORATION).
Anemia/Pancytopenia
Mitochondria are integral for the production of heme (Lane, 2006). Macrocytic and sideroblastic anemia are described (Bader-Meunier, 1999), the latter described in Pearson syndrome in which mitochondrial DNA rearrangements impact bone marrow cell proliferation, leading to pancytopenia (Wallace, 2005).
Recommendations
- If bruising is noted without an associated bleeding problem, consider discontinuation of any vitamin E supplementation.
- If persistent bruising is noted and/or an associated bleeding diathesis, consider referral to a hematologist.
References
Bader-Meunier B, Mielot F, Breton-Gorius J, et al. Hematologic involvement in mitochondrial cytopathies in childhood: A retrospective study of bone marrow smears. Pediatr Res 46(2):158-62.
Koga Y, Akita Y, Junko N, et al. Endothelial dysfunction in MELAS improved by L-arginine supplementation. Neurology 2006;66:1766-9.
Kotzailias N, Finsterer J, Zellner M, et al. Platelet function in mitochondriopathy with stroke and stroke-like episodes. Thromb Haemost 2004;91:544-52.
Lane N. Powerhouse of disease. Nature 2006;440:600-2.
Sakuta R, Nonaka I. Vascular involvement in mitochondrial myopathy. Ann Neurol 1989;25(6):594-601.
Wallace DC. A mitochondrial paradigm of metabolic and degenerative diseases, aging, and cancer: A dawn of evolutionary medicine. Annual Rev Genet 2005;39:359-407.
