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CPT®
86510

CPT® Code 86510

Official Description

Skin test; histoplasmosis

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

Histoplasmosis is an infectious disease caused by the fungus Histoplasma capsulatum, which thrives in soil enriched with organic matter, particularly in areas contaminated by bat or bird droppings. This condition is particularly prevalent in the Central and Eastern United States, as well as in certain caves in Eastern Africa. The skin test for histoplasmosis is a diagnostic procedure used to evaluate the cellular immune response of individuals who may have been exposed to this fungus. During the test, a small amount of the fungal antigen is introduced into the skin through a pinprick. The immune system's reaction to this antigen is then monitored over a specified period. A positive result from the skin test can suggest either an active infection or a previous exposure to the fungus, indicating that the individual's immune system has recognized the pathogen. This test is crucial for diagnosing histoplasmosis, especially in individuals who may be at risk due to environmental exposure.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The skin test for histoplasmosis is indicated for individuals who have had potential exposure to the Histoplasma capsulatum fungus. This includes:

  • Exposure History Individuals who have been in environments where the fungus is known to thrive, such as areas with bat or bird droppings.
  • Symptoms of Infection Patients presenting with symptoms suggestive of histoplasmosis, such as respiratory issues, fever, or fatigue, may require testing to confirm or rule out the infection.
  • Immunocompromised Patients Individuals with weakened immune systems, such as those with HIV/AIDS or undergoing immunosuppressive therapy, may be tested to assess their risk of histoplasmosis.

2. Procedure

The procedure for conducting a skin test for histoplasmosis involves several key steps:

  • Preparation The healthcare provider prepares the skin test by selecting an appropriate site, typically on the forearm, and cleans the area to prevent infection.
  • Administration of Antigen A small amount of histoplasmosis antigen is introduced into the skin using a pinprick technique. This method allows the antigen to enter the dermal layer, where it can elicit an immune response.
  • Observation After the antigen is administered, the site is monitored for a reaction. The healthcare provider will typically examine the site at intervals, usually at 48 to 72 hours post-administration, to assess for induration or swelling, which indicates a positive immune response.

3. Post-Procedure

After the skin test is performed, patients are advised to keep the test site clean and dry. They should avoid scratching or covering the area with bandages, as this may affect the results. The healthcare provider will schedule a follow-up appointment to evaluate the test site for any reactions. A positive reaction may necessitate further diagnostic testing or clinical evaluation to determine the presence of active histoplasmosis or to assess the patient's history of exposure. It is important for patients to report any unusual symptoms that may arise following the test.
Short Descr HISTOPLASMOSIS SKIN TEST
Medium Descr SKIN TEST HISTOPLASMOSIS
Long Descr Skin test; histoplasmosis
Status Code Active Code
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 3 - Technical Component Only Code
Multiple Procedures (51) 0 - No payment adjustment rules for multiple procedures apply.
Bilateral Surgery (50) 0 - 150% payment adjustment for bilateral procedures does NOT apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 0 - Payment restriction for assistants at surgery applies to this procedure...
Co-Surgeons (62) 0 - Co-surgeons not permitted for this procedure.
Team Surgery (66) 0 - Team surgeons not permitted for this procedure.
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator STV-Packaged Codes
Type of Service (TOS) 5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS) T1G - Lab tests - other (Medicare fee schedule)
MUE 1
CCS Clinical Classification 235 - Other Laboratory
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
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Pre-1990 Added Code added.
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Description
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