Possible Toxicity of Tuberculostatic Agents in a Patient With a Novel TYMP Mutation Leading to Mitochondrial Neurogastrointestinal Encephalomyopathy

Abstract

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive multisystemic disorder caused by TYMP gene mutations. Here, we report on the first MNGIE patient diagnosed in Bulgaria who carries a novel homozygous TYMP mutation (p.Leu347Pro). The patient presented with gastrointestinal complaints, cachexia, hearing loss, ptosis, ophthalmoparesis, polyneuropathy, cognitive impairment, and leukoencephalopathy on magnetic resonance imaging (MRI) examination of the brain. The patient's motor capacity declined significantly, leading to wheelchair dependence several months following administration of tuberculostatic treatment, suggesting mitochondrial toxicity of these agents. The advanced stage of the disease and the poor medical condition prevented us from performing allogenic hematopoietic stem cell transplantation (HSCT). Early diagnosis is important not only for genetic counseling but also in view of the timely treatment with allogenic HSCT.

Keywords::

• mitochondria
• MNGIE
• tuberculostatic agents
• TYMP

ACKNOWLEDGEMENT

We are grateful to Dr. J. Finsterer for his valuable comments.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.