I. See Also

II. Normal Findings

  1. No Polymorphonuclear Lymphocytes (Neutrophils)
    1. Normal CSF may have 1-2 PMNs present
  2. Adults: 5 or less WBC/mm3
  3. Newborns: 20 or less WBC/mm3

III. Correction of WBCs for CSF RBC

  1. One WBC for every 500-1000 CSF RBCs

IV. Cell Differential

  1. Differential does not distinguish bacterial from viral
    1. Lymphocyte predominance in 10% Bacterial Meningitis
  2. Monocytes (Up to 50 cells/mm3)
    1. Guillain-Barre Syndrome
    2. Multiple Sclerosis
  3. Eosinophils
    1. Intracranial parasite infection
    2. Aseptic Meningitis
    3. Malignancy
    4. Ventriculoperitoneal Shunt

V. Pleocytosis (WBCs in CSF) Causes

  1. Bacterial Meningitis
    1. PMNs predominate
    2. CSF WBCs >100/mm3 in 99% of cases (>1000 for most)
  2. Viral Meningitis
    1. Lymphocytes predominate
    2. CSF WBCs usually <100/mm3
  3. Chronic intracranial inflammation (Lymphocytes)
  4. Subarachnoid Hemorrhage
  5. Thrombosis
  6. Infectious Mononucleosis
  7. CNS Parasitic Infection (Eosinophils predominate)
  8. Carcinomatous Meningitis (<100 cells)

VI. Examination pointers

  1. Acetic acid lyses CSF RBCs but leaves CSF WBCs intact
  2. Methylene blue distinguishes PMNs and Lymphocytes

VII. References

  1. Kooiker in Roberts (1998) Procedures in ER, p. 1067-75
  2. Ravel (1995) Lab Medicine, Mosby, p. 294-9
  3. Tunkel in Mandell (2000) Infectious Disease, p. 974-8
  4. Seehusen (2003) Am Fam Physician 68:1103-8 [PubMed] (or open in [QxMD Read])

Images: Related links to external sites (from Google)

Ontology: Pleocytosis (C0151857)

Definition (SNOMEDCT) Presence of greater than normal number of cells in the cerebrospinal fluid
Concepts Finding (T033)
MSH D007964
SnomedCT 91454002
English PLEOCYTOSIS, Pleocytosis of cerebrospinal fluid, Pleocytoses, pleocytosis, Pleocytosis of cerebrospinal fluid (finding), Pleocytosis
Spanish pleocitosis del líquido cefalorraquídeo, Pleocitosis, PLEOCITOSIS, pleocitosis del líquido cefalorraquídeo (hallazgo), pleocitosis
Portuguese Pleocitose, PLEOCITOSE
French Pléocytose, PLEIOCYTOSE, Pléiocytose
German Pleozytose, PLEOZYTOSE
Dutch Pleiocytose

Ontology: Leukocytes:Number Concentration (count/vol):Point in time:Cerebral spinal fluid:Quantitative (C0942430)

Concepts Clinical Attribute (T201)
English WBC # CSF, Leukocytes:NCnc:Pt:CSF:Qn, Leukocytes [#/volume] in Cerebral spinal fluid, Leukocytes:Number Concentration (count/vol):Point in time:Cerebral spinal fluid:Quantitative