Table 3.

MELAS: Initial Clinical Manifestation

Initial Symptom(s) or Sign(s) in 60 Individuals 1Number of IndividualsPercent (%)
Recurrent headaches1728
Gastrointestinal symptoms (recurrent vomiting, anorexia)1525
Limb weakness1118
Short stature/stopped growth1118
Altered consciousness712
Impaired mentation712
Hearing loss610
Exercise intolerance610
Visual symptom58
Developmental delay35
Drop attacks11
Impaired gait11

Affected individuals frequently presented with more than one manifestation.


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Adam MP, Ardinger HH, Pagon RA, et al., editors.
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