What is Lesch-Nyhan Syndrome?
Lesch-Nyhan Syndrome or also called by medical professionals as Nyhan’s Syndrome and Juvenille gout is a rare type and inheritable disorder where there is overproduction and accumulation of uric acid that can lead to kidney failure if it’s not diagnosed early.
This disease also affects joints and nervous system and it affects children at a very young age. Uric acid is a chemical waste created when there is the breakdown of purines that normally dissolves in the blood and is excreted through urination and it also helps in making the genetic blue print.
When there is an excess production of uric acid it can cause formation of crystals in the joint and can lead to a disease called gout. Lesch-Nyhan Syndrome also affects the nervous system which can cause involuntary movements and delayed development that is usually seen during infancy. Children that have this disease normally hurt themselves like they bite there nails and banging their head.
A Child with Lesch-Nyhan Syndrome
Causes of Lesch-Nyhan Syndrome
Lesch-Nyhan Syndrome is caused by gene mutation where there is an absence of the enzyme HPRT1 (hypoxanthine-guanine phosphoribosyl transferase 1) that will metabolize uric acid and produce purines.
Without the enzyme being present it can lead to build-up of uric acid in the person body that will affect the nervous system, the kidneys and other parts of the body. It normally affect boys and the Lesch-Nyhan Syndrome is considered as x-linked inherited disease because HPRT1 is located in the x chromosomes gene.
This picture beside shows that only woman are considered carriers for this type of rare disease. The risk of having a daughter carrier and a son that is affected will depend on the carrier status of the mother. Each mother has a possibility of carrying a 50% of the disease to transmit the HPRT1 in every pregnancy.
Symptoms of Lesch-Nyhan Syndrome
Usually when the affected child was born it doesn’t show any signs and symptoms but when the child reaches 3-6 months of age he will start to develop and shows these symptoms:
- The first sign that a child that was affected by the disease had this orange colored crystal deposits in the diaper.
- Growth and developmental delays are also visible especially to the male child that is affected. Some developmental delays that are visible during infant period are inability to lift head when the baby is between 4-6 months, inability to crawl or stand during 9 months, inability to walk when the infant is already 1 year of age, and there are spasms of the limbs as well as facial muscle that is normally present when the child is more than 1 year old.
- Excess uric acid level that can cause the child to have crystal deposits that will lead to a disease called gout and will results to swelling and tenderness of joints. Due the high level of uric acid that is present it can lead to the development of stones in the kidney and gallbladder.
- The patient that has Lesch-Nyhan Syndrome normally had a difficulty in speaking because of delayed development caused by the disease.
- Excessive loss of motor control that prevents the individual to stand and walk. They are dependent on wheelchairs.
- They also have a sign that is termed as self injuring behaviors. These behaviors include that they bite their nails, lips and tongue and banging their head. Normally these patients do it when they experience stress.
- They also have cognitive and impulsive behaviors such as vomiting, spitting, meeting kindness with anger, they have compulsion to do self injury, and rejecting treats or travels.
Pathophysiology of Lesch-Nyhan Syndrome
Normally, HPRT1 (hypoxanthine-guanine phosphoribosyl transferase 1) have a role in recycling purine bases. When a patient has Lesch-Nhyan Syndrome there is an absence of HPRT 1, these purines that are produce cannot be salvaged. Normally the building blocks of the DNA or so called nucleotides is responsible in DNA replication but a small part of this replication or so called degraded DNA is recycled and this process is called “salvage pathway”.
The failure of this DNA to be recycled which the “salvage enzyme” for purines which composed of Hypoxanthine and Guanine that is responsible in purine metabolism will result in increase uric acid production.
Increase in uric acid production can lead to hyperuricemia that increased uric acid crystallization that will result to inflammation and stone formation. There are still no definite reasons for the neurological and behavioral features that are shown by this disease.
Diagnosis for Lesch-Nyhan Syndrome
- The medical professionals will ask and interview about the family history.
- The Medical professionals will do different physical examination like checking the muscle condition as well as the behavior of the person affected by the disease. They also check if there are signs of delayed development and there are signs of self-inflicting injuries like the patient bite their nails.
- Blood and Urine examination for it able to detect the excess or high uric acid level.
- Checking the HPRT activity and molecular testing for the presence of HPRT gene can help to confirm the diagnosis as well doing the molecular testing can help to detect if there are any female child that is a carrier of the gene causing Lesch-Nyhan Syndrome.
Treatment for Lesch-Nyhan Syndrome
There is no specific treatment to cure this Lesch-Nyhan Syndrome. These treatments are just to help to decrease uric acid level in the body and to control other symptoms.
- Allopurinol that decrease the level of uric acid present in the body that can prevent any formation of stones in the body.
- Drink a lot of fluid that will help to the excretion of uric acid in the body.
- For neurological problem, muscle relaxant medication is given like diazepam.
- For behavioral problems like Haloperidol is given to the patient with Lesch-Nyhan Syndrome.
- To help to treat anxiety, Phenobarbital can be given to the clients with this disease.
- Giving the patient a comfortable wheelchair due to the neurologic disability like muscle twitching and muscle stiffness.
- If needed, physical restraint is applied to patients to avoid self-inflicting behaviors and all sharps or objects that can cause harm to them must be put away.
- Behavior therapy also can be given to patients to avoid behaviors like banging their head and having a cognitive and impulsive behavior.
Complication for Lesch-Nyhan Syndrome
If it’s not treated it can lead to severe and progressive disability for the patients that have this kind of disease.
Prevention for Lesch-Nyhan Syndrome
For this disease, there is no specific prevention. If you have a family history, it’s better to have a genetic counselor and have an exam to determine if the female is the carrier of the genes causing Lesch-Nyhan Syndrome.
Lesch-Nyhan Syndrome Pictures
Lesch-Nyhan Syndrome Characteristic of the Foot
Nails of a Person with Lesch-Nyhan Syndrome