Lymphocytes
MolecularAlso known as: LymphsAlso known as: LyAlso known as: Lymphoid cellscells/uL
Counts lymphocytes in blood to detect central nervous system infections or inflammation.
Normal Range
1612.5 – 3900
cells/uL
Abnormal Levels
< 850 cells/uL
> 3900 cells/uL
Specimen Type
Blood
Why This Biomarker Matters
Elevated lymphocytes in CSF indicate viral meningitis or other CNS infections requiring diagnosis and treatment. It helps differentiate between viral and bacterial causes of meningitis.
Optimal Ranges
Clinician-defined 4-point reference thresholds (cells/uL)
Default Range
850
1612.5
3137.5
3900
Low
850 cells/uL
Borderline Low
1612.5 cells/uL
Optimal
3137.5 cells/uL
Borderline High
3900 cells/uL
Overview
Lymphocytes are a type of white blood cell crucial for the adaptive immune response, including B cells (which produce antibodies), T cells (which coordinate and carry out cell-mediated immunity), and NK cells (natural killer cells). This blood test counts lymphocytes as part of the complete blood count with differential. Elevated lymphocyte counts (lymphocytosis) may suggest viral infections, certain leukemias, or autoimmune conditions. Low lymphocyte counts (lymphopenia) can indicate immunodeficiency, bone marrow disorders, or the effects of immunosuppressive therapies.
Related Health Conditions
Conditions where Lymphocytes is commonly tested
Related Health Goals
Treatments & Interventions
Therapies monitored using Lymphocytes
Research & Evidence
191 publications
Sort:
Crosstalk between the microbiota and intestinal γδ T cell compartments in health and IBD.
Gut Microbes · 2026
PMID: 41459728Review
Neuroinflammation in neurodegenerative diseases: Focusing on the mediation of T lymphocytes.
Neural Regen Res · 2026
PMID: 40536931Other
Comparative evaluation of human T lymphocytes in HIV patients treated with lamivudine + zidovudine combined with nevirapine versus efavirenz.
Medicine (Baltimore) · 2026
PMID: 41961664
The cost-effectiveness of tumour-infiltrating lymphocyte cell therapy for advanced melanoma: a systematic review.
BMC Cancer · 2026
PMID: 41862835
Cytokine-mediated, organ-specific immune modulation and dysregulation of innate lymphocytes in sepsis.
Semin Immunopathol · 2026
PMID: 41961259
Memory-Phenotype CD4T Lymphocytes: A Double-Edged Sword in Immune Responses.
Tohoku J Exp Med · 2026
PMID: 41882837
Opportunities and challenges for cancer immunotherapy based on antigen cross-presentation.
Ann Med · 2026
PMID: 41758201
Research data from MEDLINE/PubMed · 191 articles
Technical Information (LOINC Codes)
Standardized laboratory codes for this biomarker
731-0PrimaryLymphocytes [#/volume] in Blood by Automated count
10*3/uL
71673-8Lymphocytes/Leukocytes [Pure number fraction] in Blood by Manual count
27936-4Lymphocytes/Leukocytes in Sputum
%
14819-7Lymphocytes/Leukocytes in Bronchial specimen by Manual count
%
71678-7Lymphocytes/Leukocytes [Pure number fraction] in Blood by Automated count
14818-9Lymphocytes/Leukocytes in Pericardial fluid by Manual count
%
17227-0Lymphocytes/Leukocytes in Synovial fluid by Automated count
%
14106-9Lymphocytes [#/volume] in Cerebral spinal fluid by Manual count
10*3/uL
30365-1Lymphocytes/Leukocytes in Blood by Flow cytometry (FC)
%
56769-3Lymphocytes/Leukocytes in Bronchial specimen by Flow cytometry (FC)
%
14822-1Lymphocytes/Leukocytes in Synovial fluid by Manual count
%
14820-5Lymphocytes/Leukocytes in Pleural fluid by Manual count
%
35049-6Lymphocytes [#/volume] in Synovial fluid
10*3/uL
14821-3Lymphocytes/Leukocytes in Peritoneal fluid by Manual count
%
26475-4Lymphocytes [#/volume] in Cerebral spinal fluid
10*3/uL
26481-2Lymphocytes/Leukocytes in Pleural fluid
%
6744-7Lymphocytes [#/volume] in Body fluid by Manual count
10*3/uL
26482-0Lymphocytes/Leukocytes in Peritoneal fluid
%
30421-2Lymphocytes/Leukocytes in Bronchial specimen
%
26479-6Lymphocytes/Leukocytes in Cerebral spinal fluid
%
26483-8Lymphocytes/Leukocytes in Synovial fluid
%
30364-4Lymphocytes [#/volume] in Blood by Flow cytometry (FC)
/uL
26476-2Lymphocytes [#/volume] in Body fluid
10*3/uL
10328-3Lymphocytes/Leukocytes in Cerebral spinal fluid by Manual count
%
13941-0Lymphocytes/Leukocytes in Body fluid by Manual count
%
20585-6Lymphocytes [#/volume] in Specimen by Automated count
10*3/uL
11031-2Lymphocytes/Leukocytes in Body fluid
%
732-8Lymphocytes [#/volume] in Blood by Manual count
10*3/uL
737-7Lymphocytes/Leukocytes in Blood by Manual count
%
26474-7Lymphocytes [#/volume] in Blood
10*3/uL
26478-8Lymphocytes/Leukocytes in Blood
%
736-9Lymphocytes/Leukocytes in Blood by Automated count
%
72219-9Lymphocytes [#/area] in Urine sediment by Microscopy high power field
/[HPF]
72364-3Lymphocytes/Leukocytes in Vitreous fluid by Manual count
%
74401-1Lymphocytes [#/volume] in Cord blood
10*9/L
74402-9Lymphocytes/Leukocytes in Cord blood
%
74461-5Lymphocytes/Leukocytes in Blood from Fetus
%
76409-2Lymphocytes [#] in Body fluid by Manual count
{#}
95220-0Lymphocytes/Leukocytes in Stem cell product by Manual count
%
95842-1Lymphocytes/Leukocytes in Sputum by Manual count
%
105870-0Lymphocytes [#/volume] in Specimen
/uL
107036-6Lymphocytes [#/volume] in Specimen by Flow cytometry (FC)
{#}/mL
107042-4Lymphocytes [#/volume] in Bone marrow by Flow cytometry (FC)
10^9/L
107155-4Lymphocytes [#/volume] in Hematopoietic progenitor cells from Blood product unit
/uL
20619-3Lymphocytes/Leukocytes in Specimen by Automated count
%
26480-4Lymphocytes/Leukocytes in Pericardial fluid
%
32697-5Lymphocytes [#/volume] in Synovial fluid by Manual count
10*3/uL
35097-5Lymphocytes [#/volume] in Peritoneal fluid
10*3/uL
35098-3Lymphocytes [#/volume] in Pleural fluid
10*3/uL
38903-1Lymphocytes [Presence] in Stool by Light microscopy
40470-7Lymphocytes [#/area] in Semen by Microscopy high power field
/[HPF]
40538-1Lymphocytes/Leukocytes in Peritoneal dialysis fluid by Manual count
%
51627-8Lymphocytes [#/volume] in Peritoneal fluid by Manual count
10*3/uL
55787-6Lymphocytes [#] in Cerebral spinal fluid by Manual count
{#}
56774-3Lymphocytes/Leukocytes in Tissue
%
59463-0Lymphocytes/Leukocytes in Dialysis fluid
%
61123-6Lymphocytes/Leukocytes in Specimen by Flow cytometry (FC)
%
66140-5Lymphocytes [#/volume] in Blood from Fetus by Manual count
10*3/uL
66761-8Lymphocytes/Leukocytes in Dialysis fluid by Manual count
%
67827-6Lymphocytes [#/volume] in Pericardial fluid
/uL
67833-4Lymphocytes [#/volume] in Pleural fluid from Fetus
/uL
68404-3Lymphocytes [#/volume] in Pericardial fluid by Manual count
10*3/uL
68405-0Lymphocytes [#/volume] in Pleural fluid by Manual count
10*3/uL
68407-6Lymphocytes [#/volume] in Vitreous fluid by Manual count
10*3/uL
71597-9Lymphocytes/Leukocytes [Pure number fraction] in Bronchial specimen by Manual count
71605-0Lymphocytes/Leukocytes [Pure number fraction] in Pericardial fluid by Manual count
71615-9Lymphocytes/Leukocytes [Pure number fraction] in Pleural fluid by Manual count
71624-1Lymphocytes/Leukocytes [Pure number fraction] in Synovial fluid by Manual count
71634-0Lymphocytes/Leukocytes [Pure number fraction] in Peritoneal fluid by Manual count
71649-8Lymphocytes/Leukocytes [Pure number fraction] in Body fluid by Manual count
71660-5Lymphocytes/Leukocytes [Pure number fraction] in Cerebral spinal fluid by Manual count
Available Lab Tests
Order tests that measure this biomarker
Absolute Lymphocyte Count
$20.68
Advanced Cardiovascular Health Basic
$132.55
Advanced Cardiovascular Health Comprehensive
$526.57
Advanced Liver Health Basic
$293.92
Advanced Liver Health Comprehensive
$1044.34
Complete Blood Count (CBC) with Differential and Platelets Blood Test
$15.79
Results in Same day to 1 business day
Total T and B Cells Test
$89.17
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