LOINC

LOINC Code 1177-5: little i 1 Ag RBC Aggl Ql (RBC)

1177-5 is a LOINC code used to identify little i 1 Ag RBC Aggl Ql (RBC) 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 little i -1 Ag. It is commonly used with the system or sample type RBC^Patient.

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 little i -1 Ag. It is commonly used with the system or sample type RBC^Patient.

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: DEPRECATED
  • Method: Aggl RBC

What it does not mean

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

Key facts

  • Deprecated little i-1 subtype [Presence] on Red Blood Cells
  • little i -1 Ag
  • Phenotype characterized by weak I Ag and strong i Ag; there is no i1 or i2 Ag or Ab
  • Agg; Agglut; Agglutination; Antigen; Antigens; Arbitrary concentration; BLOOD BANK; Erythrocytes; i; i1; little i1; Ordinal; Point in time; QL; Qual; Qualitative; Random; Red blood cells; Red blood corpusles; Screen

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

little i 1 Ag RBC Aggl Ql (RBC)Deprecated little i-1 subtype [Presence] on Red Blood CellsDeprecated little i1 Ag RBC Patient Qllittle i -1 AgBLDBKi 1 antigen, Red blood cellsACnc

Frequently asked questions

Code details

Code1177-5
SystemLOINC
Display namelittle i 1 Ag RBC Aggl Ql (RBC)
Descriptionlittle i -1 Ag
Short nameDeprecated little i1 Ag RBC Patient Ql
Componentlittle i -1 Ag
PropertyACnc
TimingPt
System (specimen)RBC^Patient
ScaleOrd
MethodAggl RBC
ClassBLDBK
StatusDEPRECATED

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released1.0
Last changed2.36

Consumer names

i 1 antigen, Red blood cells

Part names

little i -1 AgACncPtRBC^PatientOrdAggl RBCi 1 AgArbitrary ConcentrationPoint in time (spot)

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.