Lactate Dehydrogenase

(LDH)

<Pathology>

<Index>

 

 

 

Rationale

-  Detect presence of cell damage in serum, aspirate or CSF

 

Indication

-  Serum: cell necrosis

-  Aspirate: exudate vs transudate

-  CSF: bacterial vs viral

-  HIV: PCP Dx

 

Procedure

-  Venepuncture: grey tube

 

Features

-  Enzyme which catalyses conversion of pyruvate to lactate

 

Results

-  Serum

-  Elevated: cell necrosis

-   Haemolysis: haemolytic anaemia, malaria

-   Ca

-   Meningitis/encephalitis

-   Acute pancreatitis

-   Ischaemic colitis

-   HIV

-   AMI

-   As part of Cardiac Enzymes study

-   Peaks at 3-4/7

-   Elevated for 10/7

-   Replaced by use of TropI

-   False Positives in haemolysed samples

-  Aspirate Fluid

-  Pleural/pericardial effeusion

-   > 200 U/L: exudate

-   > 1000 U/L: empyema

-   < 200 U/L: transudate

-  CSF (LP)

-  Elevated: bacterial meningitis

-   May indicate viral meningitis w severe encephalitis

-  HIV Pts

-  Non-specific marker for Pneumocystitis jiroveci