Biomarker for the Early Diagnosis and Monitoring in Tyrosinemia Type 1 (BioTyrosin)
Biomarker for the Early Diagnosis and Monitoring in Tyrosinemia Type 1 (BioTyrosin)
Development of a new MS-based biomarker for the early and sensitive diagnosis of Tyrosinemia
 type 1 from blood (plasma)
Hereditary Tyrosinemia type 1 (HT-1) is a rare genetic disorder in which the newborn child
 lacks the ability to break down the amino acid tyrosine. As a result of this deficiency,
 toxic sub-stances build up in the blood and can cause liver failure, kidney dysfunction and
 neurological problems. There are two different forms of the disease - acute and chronic. The
 acute form is most common.

 Worldwide, Tyrosinemia type 1 affects about one newborn child in 100,000, although
 geo-graphical variation is seen.

 Tyrosinemia type 1 is hereditary. The disorder is caused by a defect in the gene coding for
 the enzyme responsible for breaking down tyrosine. For a child to be affected by the disease,
 both parents have to carry a defective gene. The risk of being born with Tyrosinemia type 1,
 i.e. receiving both genes from the parents, is thus 25%.

 Children with Tyrosinemia type 1 can display symptoms such as failure to gain weight and grow
 at the expected rate, diarrhea, vomiting, enlarged liver, liver failure, accumulation of
 fluid in the peritoneal cavity, kidney failure, softening of the bones (rickets) and liver
 tumors.

 The acute form usually appears in the first few months of life. The child has a slow weight
 gain plus fever, diarrhea, blood in the feces and vomiting. The liver is enlarged and
 yellowing of the skin and the whites of the eyes (jaundice) with an increased tendency to
 bleed (particularly nosebleeds) may be evident. The spleen and abdomen can also be enlarged
 and the legs swollen. Without treatment, liver failure and clotting problems can arise.

 Children with the chronic form of Tyrosinemia type 1 develop symptoms gradually. The child
 can suffer from enlarged liver, distended abdomen (due to enlarged liver and spleen, acites
 and excessive fluids), changes in skeleton, and liver and kidney failure. Symptoms such as
 abdominal pain, damage to the peripheral nerves and high blood pressure appear. In addition,
 symptoms common in acute intermittent porphyria can also occur. If the child is not treated,
 it will develop liver failure and liver tumors.

 The condition is also referred to as hepatorenal Tyrosinemia, and is the most critical
 variant of Tyrosinemia. The main function of the FAH gene is to regulate the production of
 the enzyme fumarylacetoacetase that is required to break down or metabolize amino acid
 tyrosine. The mutations of FAH gene leads to a deficiency of the enzyme fumarylacetoacetase,
 which then leads to a failure in breaking down tyrosine.

 Tyrosinemia type 1 is suspected on the basis of clinical presentation. Diagnostic
 investigations include analyses of amino acids, succinylacetone and alpha-fetoprotein.

 Today, the condition can be treated by diet, medication and liver transplantation. Liver
 trans-plantation was once the only treatment, but since a new drug was introduced in 1991,
 survival has increased significantly. Nevertheless, diet and special protein replacements
 remain an important part of life-long treatment.

 New methods, like mass-spectrometry give a good chance to characterize specific metabolic
 alterations in the blood (plasma) of affected patients that allow diagnosing in the future
 the dis-ease earlier, with a higher sensitivity and specificity.

 Therefore it is the goal of the study to identify and validate a new biochemical marker from
 the plasma of the affected patients helping to benefit other patients by an early diagnose
 and thereby with an earlier treatment.
Inclusion Criteria:

 -  Informed consent will be obtained from the patient or the parents before any study
 related procedures.

 -  Patients of both genders older than 2 months

 -  The patient has a diagnosis of Tyrosinemia type 1 or a high-grade suspicion for
 Tyrosinemia type 1

 High-grade suspicion present, if one or more inclusion criteria are valid:

 -  Positive family anamnesis for Tyrosinemia type 1

 -  Hepatomegaly

 -  Splenomegaly

 -  Ascites

 -  Coagulopathy

 Exclusion Criteria:

 -  No Informed consent from the patient or the parents before any study related
 procedures.

 -  Patients of both gender younger than 2 months

 -  No diagnosis of Tyrosinemia type 1 or no valid criteria for profound suspicion of
 Tyrosinemia type 1