Ordering Recommendation

Not recommended as a stand-alone test. Refer to Histoplasma Antibodies by CF & ID (0050627).




Semi-Quantitative Complement Fixation




2-5 days

New York DOH Approval Status

This test is New York DOH approved.

Specimen Required

Patient Preparation

Serum separator tube.

Specimen Preparation

Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.4 mL) Parallel testing is preferred and convalescent specimens must be received within 30 days from receipt of acute specimens. Mark specimens plainly as acute or convalescent.

Storage/Transport Temperature


Unacceptable Conditions

Contaminated or severely lipemic specimens.


After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)

Reference Interval

Test Number
Reference Interval
  Histoplasma Mycelia, CF Less than 1:8
  Histoplasma Yeast, CF Less than 1:8

Interpretive Data

An antibody titer greater than or equal to 1:8  is generally considered presumptive evidence of histoplasmosis. Greater than 1:32 or rising titers indicate strong presumptive evidence of histoplasmosis.

Yeast phase is regarded as more sensitive. Approximately 90-95 percent of cases have positive titers to one or both antigens. Titers to mycelial antigen are higher in chronic infection. Cross-reactions, usually at lower titers, may occur with other fungal disease. Rising titers suggest progression of infection. Skin tests in individuals previously exposed may cause titer elevation in 17-20 percent of cases.

Compliance Category



Negative fungal serology does not rule out the possibility of current infection.

Hotline History


CPT Codes

86698 x2


Component Test Code* Component Chart Name LOINC
0050330 Histoplasma Mycelia, CF 20573-2
0050335 Histoplasma Yeast, CF 20574-0
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.


  • H. Mycelia Ab
  • Histoplasma Yeast Ab
  • Histoplasmosis Antibody
Histoplasma Antibodies by CF