Symptoms improvement in children with autism spectrum disorder following Bumetanide administration

Introduction

In the past years, the prevalence of autism has risen, up to 1 out of every 58 children in the USA. Apart from behavioral therapy whose efficacy is limited, there is no pharmacological treatment proven to help the core symptoms of this condition.

Some mechanisms were offered in the past, as contributosr to symptoms of autism. Amongst them is imbalance in the stimulating versus the inhibiting action of γ-aminobutyric acid (GABA). GABA is a neurotransmitter in the brain and the nervous system.

A drug called Bumetanide is usually used for treating hypertension or heart failure. In the last few years, in lab animals and in small studies on humans, it was found that this medicine has the potential to improve symptoms of autism. The mechanism suggested to this phenomenon is associated with other activity of the drugs, changing the balance of GABA towards inhibition.

Methods

The research included 83 children in the ages of 3-6 years old, with the diagnosis of autism. 42 children were treated with Bumetanide in a dose of 0.5 milligram twice a day for 3 months. 41 children were in another group that was not treated. The two groups were similar in the severity of symptoms and demographic characteristics before intervention.

Evaluation of symptoms was done by validated questionnaires and by MRS (Magnetic Resonance Spectrometry), – which is like an MRI that can quantify and map chemical compounds in selected areas of the brain (such as GABA). The questionnaires and MRS were done in the beginning and at the ending of the research. Also, follow up was done on potential side effects of the drug.

Results

Children receiving the medication demonstrated a statistically significant improvement in core symptom of autism. In the MRS of these children, the change was found to be related to inhibition activity by GABA.

As for side effects, in the intervention group some children reported frequent urination and 3 children had a mild hypokalemia (low blood pottasium levels), corrected with oral potassium supplement.

Discussion

An important study. But as with all studies, this one also has its limitations and advantages.

Advantages – a fascinating and innovative study, offering a mechanism in which we can associate autistic symptoms improvement, to a neurologic pathway and radiologic imaging. An extensive work by researchers, collecting both clinical data (questionnaires), and biochemical and radiological data (MRS).

The limitation of the study is the fact that it is an open study. Meaning that physicians, patients and family members knew whether the children were getting treatment or not. A real improvement could only be proven in a randomized, controled, double blinded study, where half the children will receive an active drug and the other – placebo. In addition, a larger sample size will be needed, so even the researchers in this study defined this study as a pilot.