KUALA LUMPUR • A 12-year-old Malaysian boy has developed myokymia, an ailment that causes parts of the body to tremble, after being exposed to pollution in Sungai Kim Kim in Pasir Gudang.

Irfan Wafiy Idham Wazir - a pupil at Sekolah Kebangsaan Taman Bukit Dahlia - developed the Parkinson's-like condition after experiencing breathing difficulties in March.

It is believed that he had sniffed poisonous gases at the school in Johor, following which he was admitted to Sultan Ismail Hospital, Bernama reported. Irfan, the fourth of five siblings, was in hospital for 10 days, during which his health progressively deteriorated.

His mother, Ms Norlela Abu Hashim, 45, said specialists had carried out tests, including magnetic resonance imaging, to determine why Irfan's leg shook.

"His leg started to shake the second night he was in the hospital. When he was asleep, his heart was beating fast. The doctor slapped his face several times but he did not wake up, as if he was in a very deep sleep. The medical team then decided to summon the neurologist," recalled Ms Norlela.

"The neurologist told him to walk but he could not do so. I had to hold him. One time, I took him to the toilet and he fell because I forgot that he could not walk normally," Ms Norlela told Bernama.

Irfan's case was subsequently referred to Kuala Lumpur Hospital, where investigations found that he had myokymia after the poisonous gases caused his lungs to fail.

His father, Mr Idham Wazir, 49, has quit his job to focus his energies on his son, who was set to sit the Primary School Evaluation Test in September, Ms Norlela said.

On March 7, 105 students and residents near Sungai Kim Kim experienced symptoms including nausea, headaches, unconsciousness and breathing difficulties after chemicals were dumped in the river.

Then, on March 11, a second wave of people fell sick, with as many as 1,000 hospitalised within the course of several days, including eight in the intensive care unit.