LOINCActiveObservation

LOINC Code 475-4: Sulfonamide MLC [Susc]

475-4 is a LOINC code used to identify Sulfonamide MLC [Susc] in laboratory and clinical observation data. You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges. LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Sulfonamide. It is commonly used with the system or sample type Isolate.

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

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 Sulfonamide. It is commonly used with the system or sample type Isolate.

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: Observation
  • Method: MLC

What it does not mean

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

Key facts

  • Sulfonamide [Susceptibility] by Minimum lethal concentration (MLC)
  • Sulfonamide
  • ANTIBIOTIC SUSCEPTIBILITIES; AST; C75; ID; Infectious Disease; InfectiousDisease; Islt; Isol; MBC; Minimum bactericidal concentration; Minimum lethal concentration; Point in time; QNT; Quan; Quant; Quantitative; Random; Sulf; Sulfa; Sulfas; Sulfonamides; Sus; Suscept; Susceptibilities; Susceptibility; Susceptibilty

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

Sulfonamide MLC [Susc]Sulfonamide [Susceptibility] by Minimum lethal concentration (MLC)Sulfonamide Islt MLCSulfonamideABXBACTSusceptibility to SulfonamideSusc

Frequently asked questions

Code details

Code475-4
SystemLOINC
Display nameSulfonamide MLC [Susc]
DescriptionSulfonamide
Short nameSulfonamide Islt MLC
ComponentSulfonamide
PropertySusc
TimingPt
System (specimen)Isolate
ScaleQn
MethodMLC
ClassABXBACT
StatusACTIVE
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released1.0
Last changed2.19

Consumer names

Susceptibility to Sulfonamide

Part names

SulfonamideSuscPtIsolateQnMLCSusceptibility (microorganisms)Point in time (spot)Minimum lethal concentration (MLC)

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from LOINC. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.

LOINC Code 475-4 | HealthAssure