Skip to content

Bronchial Lavage Fluid White Blood Cell Differential Count

Published: August 9, 2026Updated: August 16, 2026

This test examines the types and proportions of white blood cells found in fluid collected from your airways, often used to assess lung inflammation, infection, or other respiratory conditions.

Quick summary

["It helps identify whether your lung issues may be due to infection, inflammation, or other causes."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
107497-0
Short code
WBC Bronch Ql Micro
Synonyms
WBC Bronch Ql Micro
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
4.5
Ref high
11
Critical range
2 N/A – 30 N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
microscopy-light
CPT
85004
SNOMED
900000000000003002
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Is Done

Your healthcare provider may order this test if you have symptoms like persistent cough, shortness of breath, or chest pain that suggest lung problems. It can also be used to diagnose conditions such as pneumonia, lung infections, or inflammatory diseases like asthma or COPD.

What to Expect Before the Test

You may receive a bronchoscope—a thin, flexible tube with a light and camera—to collect fluid from your airways. This procedure is usually done under sedation or local anesthesia. You might experience mild discomfort but should not feel pain.

What the Test Involves

After the fluid is collected, it is sent to a lab where it is examined under a microscope to count and identify different types of white blood cells (neutrophils, lymphocytes, eosinophils, basophils, and monocytes).

What the Results Mean

High numbers of neutrophils might indicate bacterial infection, while increased lymphocytes could suggest viral infection or chronic lung disease. Elevated eosinophils may point to allergies or asthma. Your provider will interpret the results in relation to your symptoms and medical history.

Reference range

Adult: 4.5-11.0 x 10^9/LN/A

Specimen: serum

No special preparation required. Stay well hydrated.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

WBC Differential (Bronchial Lavage)

Frequently asked questions

What does a high or low count of a specific white blood cell type suggest?
A high neutrophil count often signals bacterial infection, while a high eosinophil count may indicate allergies, asthma, or parasitic infections. Lymphocytes can be elevated in viral infections or chronic inflammatory conditions. Your provider will use these findings alongside other tests and symptoms to guide diagnosis and treatment.
How long does it take to get my results?
Results from this test are typically available within 1–2 business days, depending on lab processing times. Your provider will discuss the findings with you during a follow-up visit.
Can I eat or drink before this test?
You may eat and drink normally before the procedure unless instructed otherwise by your provider. Follow any specific fasting guidelines they provide if applicable.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy