Bita Poorshiri, Mohammad Barzegar, Sina Raeisi, Mohammadreza Afghan

Background The co-existence of two distinct disorders, Phenylketonuria (PKU) and Myasthenia Gravis (MG)in the same patient has rarely been reported. PKU is an inborn error of the metabolism resultingfrom a phenylalanine hydroxylase deficiency. MG is a chronic autoimmune disorder in whichantibodies destroy the communication between nerves and muscle, resulting in weakness of theskeletal muscles. Case presentation We report a case of a 16-year-old girl affected by classic PKU and MG. She had growth failure,poor skin pigmentation, microcephaly, seizures, and global developmental delay. The PKU wasdetected by elevated levels of phenylalanine, and confirmed by the molecular data at the age of1.5 years. The MG was suspected at the age of 14 years on the presence of gait problems, easyfatigability, ptosis, waddling gait, and difficulty in swallowing and climbing the stairs whichwere apparently not related to PKU. The MG was confirmed by the positive anti-acetylcholinereceptor (AChR) antibody test and compatible electrodiagnosis findings. The MG symptoms waswell controlled by Mestinon (pyridostigmine). Conclusion The co-existence of PKU and MG, due to the prevalence of each disease, could be a rare event.Since some symptoms of PKU and MG overlap, it is very important that the possibility of theircoexistence be kept in mind for the proper management of both diseases

Keywords: PKU,Myasthenia Gravis,mestinon,AchR-Ab

Bita Poorshiri
Tabriz University of Medical Sciences
Iran

Mohammad Barzegar
Tabriz University of Medical Sciences
Iran

Sina Raeisi
Tabriz University of Medical Sciences
Iran

Mohammadreza Afghan
Tabriz University of Medical Sciences
Iran