A five-year-old boy, said to be South Africa’s only patient suffering from the rare neurodevelopment disorder, Alternating Hemiplegia of Childhood (AHC), is responding well to treatment.

That is according to an article in the SA Medical Journal, penned by paediatric experts, LS van Hilegondsberg, and IA Michaelis.

The estimated incidence of AHC is one in one million people. “In recent years, it has become apparent that the clinical entities associated with AHC, is probably part of a wider spectrum of disorders seen with the mutations. The conditions are sometimes collectively referred to as ATP1A3-related disorders.

“Management of AHC is challenging and no specific treatment exists. The aim of the treatment is to reduce the frequency and severity of the episodes, and to manage them when they occur. Avoiding triggers can be helpful if any have been identified, but generally patients need long-term drug therapy,” said Hilegondsberg.

Hilegondsberg added that a range of therapies have shown some promise, but the currently accepted first-line therapy is flunarizine, a calcium-channel blocker. “Treatment with flunarizine resulted in a 78 percent reduction in duration, severity and frequency of hemiplegic episodes. Subsequent studies have shown similarly positive results.

Unfortunately flunarizine is not readily available in South Africa. An alternative that has shown some promise is topiramate, especially in the setting of concomitant epilepsy or migraine. In SA, topiramate is only available as a patient-motivated drug in the public healthcare sector,” said Hilegondsberg.

It was stated in the article that the boy’s mother, had reported that the child experienced unprovoked, sudden-onset paralysis of one side of his body. “At times, this started by affecting one arm, but as the episode continued, the paralysis spread to the leg. The frequency of the episodes was unpredictable, ranging from several times a week to only once a month. Occasionally both sides of the body would be involved (quadriplegia) and dystonic hand movements were reported,”.

The experts said the boy had attended pre-school but was removed because he could not cope. “He spoke in short sentences and was able to perform simple tasks. We used the drug, verapamil, to treat him. The boy has responded well to treatment. He tolerated the treatment with no adverse effects. During six months of treatment, there was a marked reduction in the frequency, severity and duration of the hemiplegic episodes. Episodes only occurred about once a month.

“The extent of the paralysis with each episode was less severe, and symptoms would always resolve in less than 24 hours. Owing to the improved control of his episodes, he was able to enrol successfully in a special-needs school. His progress is being monitored closely ,” said Hillegondsberg.