Glutamate Dehydrogenase (GLDH)

Glutamate dehydrogenase (GLDH) essentially plays a catabolic role (“breakdown of metabolites”) by catalyzing the excretion of nitrogen from the organism via the release of ammonia from glutamate.

GLDH elevation is an indicator of severe parenchymal cell damage (parenchyma: part of the liver containing hepatocytes/liver cells) and is a marker of liver disease with cell necrosis (cell death). GLDH is liver-specific. The activity of GLDH is 10-fold higher in the liver than in other tissues, and it is localized exclusively mitochondrially (“in the mitochondria“: power plants of cells).

The process

Material needed

  • Blood serum

Preparation of the patient

  • Not necessary

Disruptive factors

  • None known

Standard values

Gender Normal values in U/l (old reference range) Normal values in U/l (new reference range)
Female < 3,0 < 5,0
Male < 4,0 < 7,0
1st month of life (LM) < 6,6
1ST-6TH LM < 4,3
7TH-12TH LM < 3,5
13-24 LM < 2,8
2nd-3rd year of life (LY) < 2,6
13-15 LY < 3,2

Indications

  • Assessment of severity (necrosis) and extent of acute liver parenchymal injury.
  • Differential diagnosis of liver disease
  • Alcohol abuse (alcohol abuse)

Interpretation

Interpretation of increased values

  • Acute liver congestion
  • Alcohol abuse [GLDH as a marker of alcohol withdrawal.]
  • Hepatitis, necrosing (liver inflammation).
  • Hepatocellular carcinoma (HCC, liver cancer).
  • Intoxications from volatile anesthetics (halothane) – agents used to induce and induce anesthesia.
  • Intoxications (poisoning) by fungi.
  • Liver metastases
  • Liver cirrhosis (connective tissue remodeling of the liver associated with functional impairment) [GLDH initially greatly elevated, later slightly elevated].
  • Steatosis hepatis (fatty liver) [GLDH slightly elevated]

Interpretation of lowered values

  • Not relevant to the disease

Further notes

  • GLDH is mainly localized in mitochondria and is essentially liver-specific:
    • Mild liver damage → γ-GT ↑
    • Moderate liver damage → cytoplasmic ALT (GPT) ↑ and AST (GOT) ↑
    • Severe liver damage → mitochondrial GLDH ↑ and AST (GOT) ↑
  • Because GLDH is localized exclusively intramitochondrially, this parameter is a significant indicator for estimating hepatocellular death or liver damage.
  • The half-life is <18 h.
  • To determine liver function, aspartate aminotransferase (AST, GOT), alanine aminotransferase (ALT, GPT), gamma-glutamyl transferase (gamma-GT), alkaline phosphatase (AP), and bilirubin should also always be measured.