gamma-glutamyl transpeptidase deficiency

Gamma-glutamyl transpeptidase (GGT) deficiency, also known as low GGT syndrome, is a rare disorder characterized by decreased levels of the enzyme gamma-glutamyl transferase in the blood and urine. This condition leads to an accumulation of glutathione, a powerful antioxidant, in the plasma and urine.

Key Features:

• Increased glutathione concentration: The primary hallmark of GGT deficiency is elevated levels of glutathione in the plasma and urine.
• Reduced gamma-glutamyltransferase level: This condition is associated with decreased serum levels of the enzyme gamma-glutamyl transferase (GGT).
• Abnormal metabolism/homeostasis: Individuals with GGT deficiency may experience abnormalities in metabolic processes, including reduced GGT activity.

Clinical Features:

• Constipation: Some individuals with GGT deficiency may experience constipation.
• Easy bruising and mild mental symptoms: A large accumulation of glutathione can lead to easy bruising and mild mental symptoms, such as asthma.
• Other symptoms: Additional symptoms associated with this condition include jaundice (yellow skin and eyes), diarrhea or pale, greasy stool, and dark-colored urine.

Prevalence and Diagnosis:

• Rare disease: GGT deficiency is a rare disorder, with only a few reported cases in the literature.
• Diagnostic criteria: The diagnosis of GGT deficiency is based on decreased serum levels of GGT and increased glutathione concentration in the plasma and urine.

References:

• [4] Gamma-glutamyl transpeptidase deficiency is characterized by increased glutathione concentration in the plasma and urine.
• [5] These disorders have normal or low serum levels of an enzyme known as gamma-glutamyl transferase (GGT) and, therefore, may be collectively known as low GGT.
• [8] γ-Glutamyl transpeptidase deficiency (glutathionuria, OMIM 231950) is a rare disease, with only six patients reported in the literature.

Signs and Symptoms of Gamma-Glutamyl Transpeptidase Deficiency

Gamma-glutamyl transpeptidase (GGT) deficiency is a rare metabolic disorder characterized by the lack of GGT enzyme activity. The symptoms of this condition can vary in severity and may include:

• Jaundice: Yellowing of the skin and whites of the eyes, which can be a sign of liver dysfunction [6][7].
• Dark-colored urine: A possible indication of liver or kidney problems [4][5].
• Light-colored stool: A symptom that can be associated with bile duct issues [3][10].
• Easy bruising: Due to impaired clotting mechanisms, which may be related to the deficiency [13].
• Behavioral and neurological symptoms: Such as developmental delays, seizures, and muscle weakness, which are apparent from a young age and become more pronounced over time [14].

Other possible symptoms

• Diarrhea or pale, greasy stool: May indicate liver or bile duct issues [6][10].
• Abdominal swelling and pain: Can be associated with liver dysfunction [8].
• Pruritus (severe itching): A symptom that can be related to liver injury [8].

Important note

Gamma-glutamyl transpeptidase deficiency is a rare condition, and the symptoms listed above may not be present in all cases. If you suspect you or someone else has this condition, it's essential to consult with a healthcare professional for proper diagnosis and treatment.

References:

[3] - Context result 3 [4] - Context result 4 [5] - Context result 5 [6] - Context result 6 [7] - Context result 7 [8] - Context result 8 [10] - Context result 10 [13] - Context result 13 [14] - Context result 14

Diagnosing Gamma-Glutamyl Transpeptidase (GGT) Deficiency

Gamma-glutamyl transpeptidase (GGT) deficiency is a rare genetic disorder that affects the liver and other organs. Diagnosing this condition can be challenging, but several diagnostic tests are available to help healthcare providers confirm the diagnosis.

Elevated Glutathione Levels in Urine or Plasma

One of the key indicators of GGT deficiency is elevated levels of glutathione in urine (glutathionuria) or plasma [6]. This test can be used to diagnose GGT deficiency, especially when combined with other diagnostic tests.

GGT Testing Using Blood

Blood testing for GGT is considered medically necessary for evaluating liver function, injury, or disease [3, 5]. In the context of GGT deficiency, blood testing may show decreased levels of the enzyme gamma-glutamyl transferase (GGT) [8].

Other Diagnostic Tests

In addition to elevated glutathione levels and low GGT levels in blood, other diagnostic tests may be used to confirm a diagnosis of GGT deficiency. These include:

• Genetic testing: This can help identify genetic mutations that cause GGT deficiency.
• Liver function tests: These can assess liver damage or dysfunction.
• Imaging studies: Such as ultrasound or CT scans, may be used to evaluate liver structure and function.

References

[3] Clinical resource with information about gamma-Glutamyltransferase deficiency and its clinical features, GGT1, available genetic tests from US and labs...

[5] GGT testing using blood is considered medically necessary for any of the following indications: To evaluate liver function, injury or disease.

[6] Dec 1, 2022 — Diagnosis of GGT deficiency can be made by measuring elevated glutathione levels in urine (glutathionuria) or plasma. The diagnosis may also be...

[8] Decreased level of the enzyme gamma-glutamyltransferase (GGT). GGT is mainly present in kidney, liver, and pancreatic cells, but small amounts are present in...

Current Status of Drug Treatment for Gamma-Glutamyl Transpeptidase Deficiency

Unfortunately, there is no specific treatment available for gamma-glutamyl transpeptidase (GGT) deficiency. According to the search results, no specific treatment has been proposed or tested [3]. The prognosis of GGT deficiency is hard to predict as only seven patients have been reported in the literature [3].

However, some studies suggest that certain drugs may be able to decrease GGT levels. For example, clofibrate and oral contraceptives (birth control pills) can decrease GGT levels [4]. Additionally, N-acetylcysteine has been shown to correct low levels of tissue glutathione in GGT-deficient mice [6].

It's worth noting that these findings are based on limited research and more studies are needed to better understand the potential treatment options for GGT deficiency. As stated in one of the search results, more research is required to better understand the pathophysiology of GGT-1 and to identify effective therapeutic approaches [8].

In summary, while there is no established drug treatment for gamma-glutamyl transpeptidase deficiency, some studies suggest that certain medications may be able to decrease GGT levels. However, further research is needed to confirm these findings and to develop effective therapeutic strategies.

References:

[3] No specific treatment has been proposed or tested. [4] Drugs that can decrease GGT levels include clofibrate and oral contraceptives (birth control pills). [6] N-acetylcysteine has been shown to correct low levels of tissue glutathione in GGT-deficient mice. [8] More research is required to better understand the pathophysiology of GGT-1 and to identify effective therapeutic approaches.

Gamma-glutamyl transpeptidase (GGT) deficiency is a