What does this LOINC code represent?

This LOINC code identifies a lab observation, measurement, question, or clinical concept in a standardized format.

Is this enough to understand my test result?

No. The code identifies the test or observation, but the interpretation depends on the actual result, reference range, and clinical context.

LOINCActiveObservation

LOINC Code 50558-6: Nitrite Auto test strip Ql (U)

Name: LOINC Code 50558-6: Nitrite Auto test strip Ql (U)
Creator: HealthAssure Clinical Team
Published: 2026-05-21T08:59:34.496Z

50558-6 is a LOINC code used to identify Nitrite Auto test strip Ql (U) 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 Nitrite. It is commonly used with the system or sample type Urine.

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 Nitrite. It is commonly used with the system or sample type Urine.

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: Test strip.automated

What it does not mean

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

Key facts

Nitrite [Presence] in Urine by Automated test strip
Nitrite
Auto; Automated detection; Dip stick; Dipstick; Elec; Elect; Electr; NO2; Ordinal; Point in time; PR; QL; Qual; Qualitative; Random; Screen; UA; UR; URINALYSIS; Urn

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

Nitrite Auto test strip Ql (U)Nitrite [Presence] in Urine by Automated test stripNitrite Ur Ql Strip.autoNitriteUANitrite, UrinePrThr

Frequently asked questions

Code details

Code50558-6

SystemLOINC

Display nameNitrite Auto test strip Ql (U)

DescriptionNitrite

Short nameNitrite Ur Ql Strip.auto

ComponentNitrite

PropertyPrThr

TimingPt

System (specimen)Urine

ScaleOrd

MethodTest strip.automated

ClassUA

StatusACTIVE

Order/ObservationObservation

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.22

Last changed2.73

Consumer names

Nitrite, Urine

Part names

NitritePrThrPtUrineOrdTest strip.automatedPresence or ThresholdPoint in time (spot)Test strip automated

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.