Mitochondrial complex V deficiency


Mitochondrial complex V deficiency is a shortage of a protein complex called “complex V” or a loss of its function. Its symptoms can affect a wide range of organs and systems of the body; in particular the nervous system and the heart. Furthermore, it can cause feeding problems, slow growth, hypotonia, lethargy, and developmental delays. Due to the high level of lactic acid it triggers, it can cause nausea and vomiting. In some cases, high level of ammonia can cause abnormal brain function and can damage other organs.

First-Step team of experts treated children with Mithochondrial complex V deficiency. Read below Loane’s experience with the therapeutic process.


Loane was born with a rare genetic syndrome – Complex V deficiency Mitochondrial disease. At the age of 5 and a half, she couldn’t walk and didn’t talk, except the word “no”.

She sat in the W-position, crawled using six-points, or propelled herself on her bottom. Today, after a number of developmental processes, Loane is walking almost freely. Even when she falls down she knows how to get up on her own, she plays with other children, understands everything, is able to explain herself – and her progress surprises the doctors and teachers at school.

“Before this therapy, Loane was as if in a shell. In Tel Aviv the shell was broken and Loane became open to the world around her – she is cheerful and happy with life. That was not the case during her first years of life”.– Sandra and Christophe Corpataux, Loane’s parents.

Loane and First-Step article featured on AEMO’s (Association for Childhood & Rare Diseases) page