What Is Jervell And Lange Nielsen Syndrome?
Jervell and Lange-Nielsen Syndrome is an extremely rare inherited pathological condition which is characterized by congenital deafness and abnormalities in the electrical activity of the heart. The severity of the cardiac abnormalities differs from individual to individual depending on the acuity of the condition.
While some individuals with Jervell and Lange-Nielsen Syndrome may be completely asymptomatic others may have significant symptoms ranging from abnormally increased heartbeats causing loss of consciousness or even in some cases cardiac arrest.
These symptoms may be triggered by any type of stress or excitement which may result in abrupt loss of consciousness. These symptoms usually start from early childhood and follows an autosomal recessive trait meaning that two copies of the faulty gene needs to be inherited from each parent for a child to develop Jervell and Lange-Nielsen Syndrome.
What Are The Causes Of Jervell And Lange Nielsen Syndrome?
It is believed that the main cause of Jervell and Lange-Nielsen Syndrome is mutation of two genes KCNQ1 and KCNE1. The mutation of these genes results in production of a dysfunctional protein which is extremely vital for proper electrical functioning of the cochlea which is the inner part if the ear and the heart.
If the electrical activity of these two parts is impaired then the electrical impulses from these parts are not able to be carried to the brain resulting in the abnormalities within the ear and the heart with hearing defects and cardiac abnormalities which are classic for Jervell and Lange-Nielsen Syndrome.
It is an autosomal recessive disorder meaning that two copied of the faulty gene inherited from each parent is required for a child to develop Jervell and Lange-Nielsen Syndrome.
What Are The Symptoms Of Jervell And Lange Nielsen Syndrome?
The symptoms of Jervell and Lange-Nielsen Syndrome start from early childhood with the child having difficulty hearing. This hearing deficit may be present at the time of birth or may develop as the child ages. The hearing defect is because of the inability of the auditory nerves to transmit sensory information to the brain due to the electrical abnormality caused by Jervell and Lange-Nielsen Syndrome.
Additionally, there are cardiac abnormalities in which the child will have recurrent episodes of near syncope or syncope meaning partial or complete loss of consciousness. These episodes may be activated by any activity which may excite or startle the child such as a sudden sound of phone ringing and the like.
In some cases, the child may go into ventricular fibrillation which can potentially be life threatening. In some cases, there may be no particular cause for the child having syncopal episodes due to Jervell and Lange-Nielsen Syndrome.
How Is Jervell And Lange Nielsen Syndrome Diagnosed?
A thorough medical and clinical evaluation will be conducted to begin with in order to diagnose Jervell and Lange-Nielsen Syndrome. An EKG will also be done to check the electrical activity of the heart which in cases of Jervell and Lange-Nielsen Syndrome will be abnormal. This finding coupled with the hearing deficit is a virtual give away confirming the diagnosis of Jervell and Lange-Nielsen Syndrome.
In addition, a genetic testing may be conducted which will clearly show mutation of the genes KCNQ1 and KCNE1 which will definitively confirm the diagnosis of Jervell and Lange-Nielsen Syndrome.
How Is Jervell And Lange Nielsen Syndrome Treated?
The mainstay of treatment for Jervell and Lange-Nielsen Syndrome is treating the hearing loss and the cardiac abnormalities as much as possible. The treatment is purely symptomatic and supportive.
Hearing aids may be provided for hearing deficits. Additionally, a cochlear implant can be very effective in treating hearing deficit caused by Jervell and Lange-Nielsen Syndrome.
To prevent any serious threats such as cardiac arrests or syncopal episodes the child should be kept away from any event which may cause stress to the child or cause the child to get startled like taking the child for a movie, participating in sporting activities, and making the child emotional.
Additionally, medications will be provided to keep the heartbeats in check so that it may not go out of control and cause a syncopal event. Beta blockers are given for cardiac abnormalities. The most preferred medications for controlling this condition are atenolol and propanolol.
These medications will decrease the workload on the heart and control a lot of the symptoms. In certain cases where beta blockers are not effective in controlling the symptoms then a procedure in which a device called ICD which stands for automatic cardioverter-defibrillator is placed to normalize the electrical activity of the heart as much as possible.
Placement of ICD is always done in conjunction with antiarrhythmia medications to normalize the heart as much as possible in Jervell and Lange-Nielsen Syndrome.