LOINC Code 75639-5: LDH.body fld/Lactate dehydrogenase in serum (Body fld+S/P) [Relative ratio]

What is this code?

LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Lactate dehydrogenase.body fld/Lactate dehydrogenase.serum. It is commonly used with the system or sample type Body fld+Ser/Plas.

When is it used?

• Used in lab systems, EHRs, and clinical data exchange.
• May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
• Status: ACTIVE
• Order vs observation: Both

What it does not mean

• The code identifies the observation or test, not the actual result.

Key facts

• Lactate dehydrogenase in body fluid/Lactate dehydrogenase in serum
• Lactate dehydrogenase.body fld/Lactate dehydrogenase.serum
• LDH body fluid to LDH serum ratio aids in determining whether a fluid is an exudate (actively secreted fluid, e.g. due to inflammation), or transudate (passively secreted fluid, due to high hydrostatic pressure or low oncotic pressure). The usual criterion is that a ratio of fluid LDH versus upper limit of normal serum LDH of more than 0.6 or 2⁄3 indicates an exudate, while a ratio of less indicates a transudate.
• 2-Hydroxypropanoic acid; 2-hydroxy-propionate; 2-hydroxy-propionic acid; B/F; BF; bod; Bodies; Body fluid; Body fluid, unsp; Chemistry; Dehydrog; Dehyrdogenase; Fl; Fld; Fld+SerPl; FLU; Fluid; L.D.H; Lact; Lactic acid; Lactic acid dehydrogenase; LD; LDH; LDH.body fld; LDH.serum; L-lactate; L-lactate dehydrogenase; Pl; Plasma; Plsm; Point in time; QNT; Quan; Quant; Quantitative; Random; Relative ratio; Ser; SerP; SerPl; SerPlas; Serum; Serum or plasma; SR; Tumor marker

Where you may see this code

You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.

Common synonyms

Frequently asked questions