Epic Code LAB2111209 Histoplasma Antibody, Serum
Additional Codes
Mayo code: SHSTO
Epic code: LAB 2111209
Order Alias: 11271
Cerner: 2795
Performing Laboratory
Mayo Clinic Laboratories in RochesterUseful For
Aiding in the diagnosis of active histoplasmosis using serum specimens
Specimen Type
SerumSpecimen Required
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.5 mL
Collection Instructions: Centrifuge and aliquot serum into plastic vial.
COLLECTION NOTE: Volumes listed are in serum or plasma, draw approximately 2 1/2 times the requested volume in whole blood.
Special Instructions
Specimen Minimum Volume
See Specimen Required
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 14 days | |
Frozen | 14 days |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Day(s) Performed
Monday through Friday
Reference Values
MYCELIAL BY COMPLEMENT FIXATION (CF):
Negative (positives reported as titer)
YEAST BY CF:
Negative (positives reported as titer)
ANTIBODY BY IMMUNODIFFUSION:
Negative (positives reported as band present)
Clinical Information
Histoplasma capsulatum is a soil saprophyte that grows well in soil enriched with bird droppings. The usual disease is self-limited, asymptomatic, and affects the lungs. Chronic cavitary pulmonary disease, disseminated disease, and meningitis may occur and can be fatal, especially in young children and in immunosuppressed patients.
Cautions
Recent histoplasmosis skin tests must be avoided because the test causes a misleading rise in complement fixation titer, as well as an M precipitin band, in approximately 17% of patients having previous exposure to Histoplasma capsulatum.
Cross-reacting antibodies sometimes present interpretive problems in patients having blastomycosis or coccidioidomycosis.
Interpretation
Complement fixation (CF) titer results of 1:32 or higher indicate active disease. A rising CF titer is associated with progressive infection.
Positive immunodiffusion test results supplement findings of the CF test. The simultaneous appearance of both H and M precipitin bands indicates active histoplasmosis. The M precipitin band alone indicates early or chronic disease or a recent histoplasmosis skin test.
Patients infected with Histoplasma capsulatum demonstrate a serum antibody with a rising titer within 6 weeks of infection. A rising titer is associated with progressive infection. Specific antibody persists for a few weeks to a year, regardless of clinical improvement.
Reporting Name
Histoplasma Ab, SMethod Name
Complement Fixation (CF)/Immunodiffusion (ID)
Method Description
Both immunodiffusion and complement fixation (CF) tests are used to detect antibodies to Histoplasma capsulatum. For immunodiffusion, the antigen used is a culture filtrate. Histoplasmin H and M precipitins can be identified by the assay. For the CF test, antigens are histoplasmin and a yeast form antigen of Histoplasma capsulatum; the latter is more sensitive.(Roberts GD: Fungi. In: Washington II JA, ed. Laboratory Procedures in Clinical Microbiology. 2nd ed. Springer-Verlag, 1985; Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Elsevier; 2020)
CPT Code Information
86698 x 3
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
SHSTO | Histoplasma Ab, S | 90227-0 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
15121 | Histoplasma Mycelial | 20573-2 |
15122 | Histoplasma Yeast | 20574-0 |
15123 | Histoplasma Immunodiffusion | 90232-0 |
Report Available
2 to 7 daysTest Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.Clinical Reference
1. Kaufman L, Kovacs JA, Reiss E: Clinical Immunomycology. In: Rose NR, de Macario ED, Folds JD, Lane HC, Nakamura RM, eds. Manual of Clinical and Laboratory Immunology. 5th ed. ASP Press; 1997
2. Deepe GS: Histoplasma capsulatum histoplasmosis. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Elsevier; 2020:3162-3176
Forms
If not ordering electronically, complete, print, and send Infectious Disease Serology Test Request (T916) with the specimen.