Lamellar Body Count
Label Mnemonic: LBC
Epic code: LAB9202
Order form: Laboratory Requisition
Supply order: Supply Order Form
Billing: Billing Policies
CPT code: 83664
Specimen(s):
Amniotic Fluid
Collection Medium:
Yellow top round bottom tube (no additive)
Minimum:
2 mL Amniotic Fluid
Testing Schedule:
24 hours upon receipt at reference laboratory.
Turn Around Time:
24 hours upon receipt at reference laboratory (upon receipt in laboratory)
Reference Range:
Immature: <15,000/mcL
Indeterminate: 15,000-50,000/mcL
Mature: >50,000/mcL

Cutoffs are based on consensus protocol (Neerhof M, Dohnal JC, Ashwood ER, et al: Lamellar body counts: a consensus on protocol. Obstet Gynecol. 2001;97:318-320)
Interpretive Data:
Amniotic fluid lamellar body counts (LBC) above 50,000/mcL are predictive of fetal lung maturity.

Amniotic fluid LBC below 15,000/mcL are suggestive of fetal lung immaturity and increased risk of neonatal respiratory distress syndrome (RDS).

The main value of fetal lung maturity testing is predicting the absence of RDS. An immature test result for fetal lung maturity is less reliable in predicting the presence of RDS.(1)
Comments:
If amniotic fluid contains meconium or blood, the LBC is cancelled.

This test replaces the "Fetal Lung Maturity" test.
Methodology:
Impedance
Instructions:
Sample should NOT be frozen.
Sample Processing:
Submit in leak-proof container.
Do Not Centrifuge.
Sample Storage:
Refrigerate, 2-8°C.
Transport Instructions:
Place labeled specimen into zip-lock type biohazard bag; seal bag.
Place requisition into outside pocket of bag.
Transport in cooler with refrigerated coolant packs.
CPT Code:
83664