HealthAssure
HealthAssureGood Life
LOINCActiveBoth

LOINC Code 78958-6: Cathepsin A (WBC) [Catalytic activity/Mass]

78958-6 is a LOINC code used to identify Cathepsin A (WBC) [Catalytic activity/Mass] 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 Cathepsin A. It is commonly used with the system or sample type WBC.

Reviewed by HealthAssure Clinical TeamUpdated 25 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 Cathepsin A. It is commonly used with the system or sample type WBC.

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

  • Cathepsin A [Enzymatic activity/mass] in Leukocytes
  • Cathepsin A
  • Cathepsin A enzyme activity in leukocytes is measured as part of a diagnostic work-up for galactosialidosis. Patients with galactosialidosis will have decreased activity of the protective protein as well as decreased neuraminidase and β-galactosidase activity in leukocytes (and/or fibroblasts). Sequencing of the CTSA gene is performed for detection of disease-causing mutations.
  • Catalytic Content; Chemistry; Galactosialidosis; Galactosidase; Leukocytes; Lysosomal Protective Protein; Point in time; QNT; Quan; Quant; Quantitative; Random; WBCs; White blood cells

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

Cathepsin A (WBC) [Catalytic activity/Mass]Cathepsin A [Enzymatic activity/mass] in LeukocytesCathepsin A WBC-cCntCathepsin ACHEMCathepsin A, White blood cellsCCnt

Frequently asked questions

Code details

Code78958-6
SystemLOINC
Display nameCathepsin A (WBC) [Catalytic activity/Mass]
DescriptionCathepsin A
Short nameCathepsin A WBC-cCnt
ComponentCathepsin A
PropertyCCnt
TimingPt
System (specimen)WBC
ScaleQn
ClassCHEM
Example unitsnmol/H/mg protein
StatusACTIVE
Order/ObservationBoth

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.54
Last changed2.54

Consumer names

Cathepsin A, White blood cells

Part names

Cathepsin ACCntPtWBCQnCatalytic ContentPoint in time (spot)White blood cells

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.