Lymphocytic Choriomeningitis

Label Mnemonic:	LCM
Epic code:	LAB3525
Downtime form:	Doctor/Provider Orders - Pathology Core and Specialty Care Nursery

Commercial Mailout Laboratory
6240-8 RCP
356-8593

Specimen(s):

Serum

Collection Medium:

Red top tube 5 mL (Clot Activator)

Minimum:

Preferred Minimum: 1 mL serum from red top tube
Absolute Minimum: 0.2 mL serum from red top tube

Rejection Criteria:

Contaminated, hemolyzed, or severely lipemic specimens.

Turn Around Time:

1-5 days upon receipt at reference laboratory

Reference Range:

Lymphocytic Choriomeningitis (LCM) Virus Antibody, IgG
  Less than 1:10 Negative - No significant level of LCM virus IgG
  antibody detected.

  Greater than or equal to 1:10 Positive - Presence of IgG antibody
  to LCM virus detected, suggestive of current or past infection.

Lymphocytic Choriomeningitis (LCM) Virus Antibody, IgM
  Less than 1:10 Negative - No significant level of LCM virus IgM
  antibody detected.

  Greater than or equal to 1:10 Positive - Presence of IgM antibody
  to LCM virus detected, suggestive of current or past infection.

Interpretive Data:

The best evidence for current infection is a significant change on two appropriately timed specimens, where both tests are done in the same laboratory at the same time.

Comments:

Acute and convalescent samples must be labeled as such; parallel testing is preferred and convalescent samples must be received within 30 days from receipt of the acute samples. Please mark sample plainly as "acute" or "convalescent."

Test Limitations:

Lymphocytic choriomeningitis (LCM) is caused by an RNA virus now 
classified as an arenavirus. Rodents are the primarily reservoir. 
Clinically, infection usually presents as an acute influenza-like 
illness. Symptoms develop 5-10 days after exposure. Most patients 
develop fevers of 101-104 degrees F with chills and muscle rigidity. 
Other symptoms may include malaise, retro-orbital headache, 
photophobia, weakness, anorexia, nausea, and light-headedness. Some 
patients may experience sore throat. Symptoms may improve after five 
days to three weeks, but some suffer relapse with meningeal symptoms.

The CF test is often used to screen aseptic meningitis specimens 
against a battery of antigens and a CF antigen is often appropriately 
included in this battery.

Methodology:

Semi-Quantitative Indirect Fluorescent Antibody

CPT Code:

86727(x2)