Anallergy isan abnormal reaction of the human immune system, when it wrongly identifies certain allergens such as pollens, foods, drugs, dust, etc to be harmful foreign substances and produces antibodies against them. When these antibodies are produced in excess, they release histamine and other chemicals in your body, which in turn results in some allergic reaction. Allergy manifests itself most frequently in the respiratory tract or the skin – these manifestations of allergic conditions include allergic rhinitis, eczema, hives and hay fever. Severe reactions include violent cough, cyanosis, fever, pulse variations, convulsions and collapse. Allergic reactions may be acute, chronic, immediate or delayed and the agent causing the allergy is to be identified to provide apt treatment – avoidance, medication or immunotherapy treatment.

Allergy coding involves coding procedures that come under allergy testing, immunization and desensitization. Coders tend to be confused as regards the various types of allergy testing, those who can do the testing, how allergy shots can be properly billed, and so on. Coding for allergy is made more complex with details such as the allowed limits, combinations, units and same day evaluation/management services.The patient’s medical record must clearly document the medical necessity for each test performed, the test results, unfavorable reactions if any to each test, for each date of service submitted on the claim.

Allergy Testing Coding

To know if you are allergic, you need to be tested for inhalants known to cause allergies, for food allergies and so on. Allergy testing is categorized into in vivo and in vitro methodologies. Allergy testing is covered only when it is considered ‘medically necessary’ and is ordered by a physician. The physical examination should indicate allergic signs/symptoms. Allergy testing is also covered when a diagnosis such as asthma, indicative of an allergy has been made.Covered CPT codes include the range 95004-95199. Investigational allergy tests are not usually covered.

In vivo testing includes allergy skin testing:

Percutaneous test (scratch, prick or puncture test)
CPT codes covered: 95004, 95010

Percutaneous test is the allergy sensitivity test most frequently performed; however, the following cutaneous and mucous membrane tests are sometimes included in an allergy evaluation:

Intracutaneous test (intradermal test)
CPT codes covered: 95015 95024 95027 95028

Photo Patch test
CPT codes covered: 95052; the number of tests has to be specified

Patch or application test(s)
CPT code covered: 95044; the number of tests has to be specified

Photo Tests
CPT code covered: 95056

Bronchial Challenge Test
CPT codes covered: 95070 95071 Other CPT codes related to the CPB: 94150 94200 94240 94350 94360 94621 94680 94681 94690 94720 94770

Exercise Challenge Test
CPT codes covered: 94010 94060 94070 94150 94200 94240 94350 94360 94375 94620 94621 94680 94681 94690 94720 94770

Food ingestion challengetest
CPT code 95075

Opthalmic mucous membranetests
CPT code 95060

Direct nasal mucous membrane test
CPT code 95065

Serial endpoint titration (SET) test (eg, intradermal dilutional testing [IDT]
CPT code covered: 95027

Provocative test (for example, Rinkel test)
CPT code: 85078

Percutaneous and intracutaneous allergy tests are accepted as medically necessary and are covered by most insurance providers. However, there are certain limitations imposed:

The number of scratch, puncture or prick allergy tests eligible for reimbursement per year is 70 (CPT code 95004)
The number of intracutaneous allergy tests eligible for reimbursement per year is 40 (CPT codes 95024 and 95028)

SET testing is considered medically necessary and is covered up to 80 tests per year (CPT codes 95010, 95015 and 95027).

Patch test, photo patch test, mucous membrane test, bronchial inhalation challenge test, and food ingestion challenge test are also considered medically necessary and covered for the diagnosis, evaluation and treatment of allergies. Other allergy testing procedures including sublingual testing, provocative testing, and Rebuck skin window test are not covered because they are considered experimental or investigational. These are to be reported with the CPT code number 95199.

Tests such as Leukocyte histamine release, Prausnitz-Kustner test, Cytotoxic food testing (leukocytotoxic test, Bryans test) and Conjunctival challenge testing (ophthalmic mucous membrane test) are usually excluded from reimbursement.

In vitro testing involves blood tests to identify the presence of specific IgE antibodies to a particular antigen. Procedure codes for allergy tests are usually reimbursed per test for the total number of tests performed.

Allergy laboratory testing includes CPT codes 86000-86999. 86003 and 86005 are codes used to signify allergen specific IgE determinations. RAST, MAST, FAST, ELISA, and ImmunoCAPtests are indicated when percutaneous testing of IgE-mediated allergies cannot be done. Radioallergosorbent testing for allergies has to be reported with code 86003 (allergen specific IgE; quantitative or semiquantitative, each allergen).Service providers reporting with this code have to give supporting documents to validate the medical necessity for the allergy testing procedure, explaining why other routine allergy tests were unsatisfactory. These tests are reimbursed in the following situations:

When skin tests cannot be performed routinely due to conditions such as infancy, extensive eczema, icthyasis or dermographia
When the skin test has proven inconclusive
When the patient is under medication that might interfere with skin testing, but can’t be asked to discontinue
When the patient has systemic reaction to skin testing

If medical necessity is not validated, code 86003 might not be reimbursed. Apart from CPT codes, the claims should also contain all relevant ICD-9 and HCPCS codes for full reimbursement.

Allergy Immunotherapy Coding

Allergy immunotherapy includes avoidance therapy, pharmacologic therapy and immunotherapy. Avoiding the allergen responsible for causing allergy is the most effective treatment. Allergy immunotherapy also known by the terms hyposensitization, desensitization, allergy injection therapy, or “allergy shots” is recommended for patients

In whom the allergens triggering the reaction are not easily avoidable
The allergy is IgE mediated
The allergy is not effectively controlled by medication

Allergy immunotherapy desensitizes the patient to the allergen that caused the allergy. It protects the patient against the allergic symptoms and inflammatory reactions. Allergy shots are usually provided in a medical setting and contain increasing doses of the allergen. The healthcare provider must accurately document the allergy shots given to the patient to be properly reimbursed. To avoid claim denials, it is important that the patient is examined by a physician; in addition, the examining physician has to prepare the antigens, develop a treatment plan and dosage schedule.

In allergy immunotherapy, the CPT codes covered include 95115-95170, 95199. If other identifiable services are given during office visit, office visit codes can be used in addition to allergen immunotherapy codes.

Some Important Considerations

When percutaneous or intracutaneous sequential and incremental injections (95010, 95015 or 95027) and single injection (95004 or 95024) tests are provided on the same date, all these codes may be reported if the tests are different allergens or different dilutions of the same allergen. The number of separate injections are to be reported, do not report both a single injection test and a sequential and incremental injection test for the same dilution of an allergen. SET testing can be reported and will be reimbursed on a per allergen basis.

The patient’s medical record must clearly document the medical necessity for the treatment provided. Medicare Benefit Policy Manual provides details of services covered, codes and other relevant details helpful in accurate coding. A standardized CPT code is assigned for every medical procedure and task. Medical coders have to be thorough with the reimbursement policies of different insurance providers