Management & Compliance for Large/Academic Pathology Practices
Part 11 -
ICD-9-CM Coding for Diagnostic Tests
Black-Schaffer & Johnson
ICD-9-CM Coding for Diagnostic Tests
Program Memorandum, Department of Health and Human Services (DHHS), Carriers, Centers for Medicare & Medicaid Services (CMS), Transmittal B-01-61, Date: SEPTEMBER 26, 2001, CHANGE REQUEST 1724, SUBJECT: ICD-9-CM Coding for Diagnostic Tests.
Determining the Appropriate Primary ICD-9-CM Diagnosis Code For Diagnostic Tests Ordered Due to Signs and/or Symptoms
If the physician has confirmed a diagnosis based on the results of the diagnostic
test, the physician interpreting the test should code that diagnosis. The signs and/or symptoms that
prompted ordering the test may be reported as additional diagnoses if they are not fully explained or
related to the confirmed diagnosis.
If the diagnostic test did not provide a diagnosis or was normal, the interpreting
physician should code the sign(s) or symptom(s) that prompted the treating physician to order the
If the results of the diagnostic test are normal or non-diagnostic, and the
referring physician records a diagnosis preceded by words that indicate uncertainty (e.g., probable,
suspected, questionable, rule out, or working), then the interpreting physician should not code the
referring diagnosis. Rather, the interpreting physician should report the sign(s) or symptom(s) that
prompted the study. Diagnoses labeled as uncertain are considered by the ICD-9-CM Coding Guidelines as
unconfirmed and should not be reported. This is consistent with the requirement to code the diagnosis to
the highest degree of certainty.
Instruction to Determine the Reason for the Test
[R]eferring physicians are required to provide diagnostic information to the testing
entity at the time the test is ordered. [A]ll diagnostic tests "must be ordered by the physician who is
treating the beneficiary." [A]n "order" is a communication from the treating physician/practitioner
requesting that a diagnostic test be performed for a beneficiary. An order may include the following
forms of communication:
- A written document signed by the treating physician/practitioner, which is hand-delivered, mailed, or faxed to the testing facility;
- A telephone call by the treating physician/practitioner or his/her office to the testing facility; and
- An electronic mail by the treating physician/practitioner or his/her office to the testing facility.
NOTE: If the order is communicated via telephone,
both the treating physician/practitioner or his/her office and the testing facility must document the
telephone call in their respective copies of the beneficiary's medical records.
On the rare occasion when the interpreting physician does not have diagnostic
information as to the reason for the test and the referring physician is unavailable to provide such
information, it is appropriate to obtain the information directly from the patient or the patient's
medical record if it is available. However, an attempt should be made to confirm any information
obtained from the patient by contacting the referring physician.
Incidental findings should never be listed as primary diagnoses. If reported,
incidental findings may be reported as secondary diagnoses by the physician interpreting the diagnostic
Unrelated and co-existing conditions/diagnoses may be reported as additional
diagnoses by the physician interpreting the diagnostic test.
Diagnostic Tests Ordered in the Absence of Signs and/or Symptoms (e.g. screening tests)
When a diagnostic test is ordered in the absence of signs/symptoms or other evidence
of illness or injury, the physician interpreting the diagnostic test should report the reason for the
test (e.g. screening) as the primary ICD-9-CM diagnosis code. The results of the test, if reported, may
be recorded as additional diagnoses.
Use of ICD-9-CM To The Greatest Degree of Accuracy and Completeness
The interpreting physician should code the ICD-9-CM code that provides the highest
degree of accuracy and completeness for the diagnosis resulting from test, or for the sign(s)/symptom(s)
that prompted the ordering of the test.
In the past, there has been some confusion about the meaning of "highest degree of
specificity," and in "reporting the correct number of digits." In the context of ICD-9-CM coding, the
"highest degree of specificity" refers to assigning the most precise ICD-9-CM code that most fully
explains the narrative description of the symptom or diagnosis.
In order to report the correct number of digits when using ICD-9-CM, refer to the
ICD-9-CM diagnosis codes are composed of codes with 3, 4, or 5 digits. Codes with 3
digits are included in ICD-9-CM as the heading of a category of codes that may be further subdivided by
the use of fourth and/or fifth digits to provide greater specificity.
Assign three-digit codes only if there are no four-digit codes within that code
category. Assign four-digit codes only if there is no fifth-digit subclassification for that category.
Assign the fifth-digit subclassification code for those categories where it exists.
Medicare's National Correct Coding Initiative
- Pre-1996, ever-growing use of "Black Box Edits"
- National outcry from physicians abhorring BBEs
- CMS response: RFP for a vendor to provide publicly known edits
- NCCI becomes a reality in 1996
"The National Correct Coding Initiative [NCCI] was developed by the Centers for
Medicare and Medicaid Services [CMS] to promote national correct coding methodologies and to control
improper coding that leads to inappropriate payment of Medicare Part B claims."
What are NCCI edits?
NCCI edits are pairs of CPT codes that are usually not separately
The edits apply to services billed by the same provider for the same
patient on the same day.
How are NCCI edits arranged?
The edits are arranged by two sets of tables.
One table contains the Column 1 / Column 2 edits (formerly known as Comprehensive /
The other table contains the Mutually Exclusive edits.
What are Column 1 / Column 2 edits?
Column 1 / Column 2 correct coding edits contain two types of code pair
One type contains Column 2 codes that are an integral part of the Column 1
The other type contains codes that should simply not be reported together for other
reasons (e.g., "misuse of the code").
What are Mutually Exclusive edits?
Mutually Exclusive codes represent services that cannot reasonably be performed in
the same session by the same provider on the same patient.
What do the superscript numbers mean?
The "0" indicator means that no NCCI associated modifiers are allowed with the edit
The "1" indicator means that NCCI associated modifiers are allowed with the edit
The "9" indicator is used only on those code pairs that have been deleted, where the
deletion date was retroactive to the effective date.
What modifiers are allowed with NCCI edits?
-59 Distinct Procedural Service
Under certain circumstances the physician may need to indicate that a procedure or
service was distinct or independent from other services performed on the same day.
Modifier "59" is used to identify procedures / services that are not normally
reported together, but are appropriate under the circumstances.
-91 Repeat Clinical Diagnostic Laboratory Test
In the course of treatment of a patient, it may be necessary to repeat the same
laboratory test on the same day to obtain subsequent (multiple) results.
Under these circumstances, the laboratory test performed can be identified by its
usual procedure number with the addition of the "91" modifier.
How often are NCCI edits updated?
NCCI edits are updated on a quarterly basis.
The number of changes in each update varies.
You need each version update to manage your coding practices.
What is the oversight of NCCI?
American Medical Association formed the Correct Coding Policy Committee (CCPC) in
1995 to provide formal input into NCCI process.
CCPC has become a largely "virtual committee" with the single activity of
disseminating quarterly proposed edits.
There is thus no coordinated oversight of NCCI by CCPC.
NCCI also notifies individual specialty societies (CAP for pathology) of proposed
Bone and bone marrow evaluation
2. Multiple CPT codes are descriptive of services performed for bone and bone
When a biopsy is performed for evaluation of bone matrix structure, the appropriate
code to bill is CPT code 20220 for the biopsy and CPT code 88307 for the surgical pathology evaluation.
When a bone marrow aspiration is performed alone, the appropriate coding is CPT code
38220. Appropriate coding for the interpretation is CPT code 85097 when the only service provided is the
interpretation of the bone marrow smear.
When both services are performed by the same provider, both CPT codes may be
The pathological interpretations (CPT code 88300-88309) are not reported in addition
to CPT code 85097 unless separate specimens are processed.
When it is medically necessary to evaluate both bone structure and bone marrow, and
both services can be provided with one biopsy, only one code (CPT code 38221 (bone marrow biopsy) or CPT
code 20220 (bone biopsy)) can be reported.
If two separate biopsies are necessary, then both can be reported using modifier -59
on one of the codes. Pathological interpretation codes 88300-88309 may be separately reported for
multiple separately submitted specimens.
If only one specimen is submitted, only one code can be reported regardless of
whether the report includes evaluation of both bone structure and bone marrow morphology or not.
4. When cytopathology codes are reported, the appropriate CPT code to bill is that
which describes, to the highest level of specificity, what services were rendered.
Accordingly, for a given specimen, only one code from a group of related codes
describing a group of services that could be performed on a specimen with the same end result (e.g.
88104-88112, 88142-88143, 88150-88154, 88164-88167, etc.) is to be reported.
If multiple services (i.e., separate specimens) are reported, modifier -59 should be
used to indicate that different levels of service were provided for different specimens.
This should be reflected in the cytopathologic reports.
A cytopathology preparation from a fluid, washing, or brushing is to be reported
using one code from the range of CPT codes 88104-88112.
It is inappropriate to additionally use CPT codes 88160-88162 because the smears are
included in the codes referable to fluids (or washings or brushings) and 88160-88162 references "any
other source" which would exclude fluids, washings, or brushings.
Second opinion on slides, tissue, or material
6. The CPT codes 88321-88325 are to be used to review slides, tissues, or other
material obtained and prepared at a different location and referred to a pathologist for a second
These codes should not be reported by pathologists reporting a second opinion on
slides, tissue, or material also examined and reported by another pathologist in the same provider
Medicare generally does not pay twice for an interpretation of a given technical
service (e.g., EKGs, radiographs, etc.).
CPT codes 88321-88325 are reported with one unit of service regardless of the number
of specimens, paraffin blocks, stained slides, etc.
When reporting CPT codes 88321-88325, providers should not report other pathology
CPT codes such as 88312, 88313, 88342, 88187, 88188, 88189, etc., for interpretation of stains, slides or
material previously interpreted by another pathologist.
CPT codes 88312, 88313 and 88342 may be reported with CPT code 88323 if provider
performs and interprets these stains de novo.
Immunocytochemistry and flow cytometry
8. Medicare does not pay for duplicate testing.
CPT codes 88342 (immunocytochemistry, each antibody) and 88184, 88187, 88188, 88189
(flow cytometry) should not in general be reported for the same or similar specimens.
The diagnosis should be established using one of these methods.
The provider may report both CPT codes if both methods are required because the
initial method is nondiagnostic or does not explain all the light microscopic findings.
The provider can report both methods utilizing modifier -59 and document the need
for both methods in the medical record.
If the abnormal cells in two or more specimens are morphologically similar and
testing on one specimen by one method (88342 or 88184, 88187, 88188, 88189) establishes the diagnosis,
the other method should not be reported on the same or similar specimen.
Similar specimens would include, but are not limited to:
- blood and bone marrow;
- bone marrow aspiration and bone marrow biopsy;
- two separate lymph nodes; or
- lymph node and other tissue with lymphoid infiltrate.
Quantitative or semi-quantitative immunohistochemistry
9. Beginning January 1, 2004, quantitative or semi-quantitative
immunohistochemistry using computer-assisted technology (digital cellular imaging) should be reported as
CPT code 88361.
CPT code 88361 should not be used to report any service other than quantitative or
semi-quantitative immunohistochemistry using computer-assisted technology (digital cellular imaging).
Digital cellular imaging includes computer software analysis of stained microscopic
Beginning January 1, 2005, quantitative or semi-quantitative immunohistochemistry
performed by manual techniques should be reported as CPT code 88360.
Immunohistochemistry reported with qualitative grading such as 1+ to 4+ should be
reported as 88342.
DNA ploidy and S-phase analysis of tumor
10. Beginning January 1, 2004, DNA ploidy and S-phase analysis of tumor by digital
cellular imaging technique should be reported as CPT code 88358.
CPT code 88358 should not be used to report any service other than DNA ploidy and
One unit of service for CPT code 88358 includes both DNA ploidy and S-phase
Quantitative or semiquantitative tissue in situ hybridization
12. Beginning January 1, 2005, qualitative (tissue or cellular) in situ
hybridization should be reported as CPT code 88365 when performed by a physician (M.D./D.O.).
Beginning January 1, 2005, quantitative or semi-quantitative in situ hybridization
(tissue or cellular) performed by computer-assisted technology should be reported as CPT code 88367 when
performed by a physician (M.D./D.O.).
Beginning January 1, 2005, quantitative or semi-quantitative in situ hybridization
(tissue or cellular) performed by manual methods should be reported as CPT code 88368 when performed by a
Do not report CPT code 88365 with CPT codes 88367 or 88368 for the same probe.
Only one unit of service may be reported for CPT code 88365, 88367 or 88368 for each
When in situ hybridization is performed on tissue or cytology specimens by a
non-physician (provider other than M.D./D.O.), it should be reported using appropriate CPT codes in the
For each reportable probe, a provider should not report CPT codes both from the
range 88365- 88368 and the range 88271-88275.
In situ hybridization reported as CPT codes 88365-88368 includes both physician
(M.D./D.O.) and non-physician (non-M.D./D.O.) services to obtain a reportable probe result.
The physician (M.D./D.O.) work component of 88365- 88368 requires that a physician
(M.D./D.O.) rather than laboratory scientist or technician read, quantitate (88367, 88368), and interpret
the tissues/cells stained with the probe(s).
If this work is performed by a laboratory scientist or technician, CPT codes
88271-88275 should be reported.
Flow cytometry interpretation
13. Beginning January 1, 2005, flow cytometry interpretation should be reported
using CPT codes 88187-88189.
Only one code should be reported for all flow cytometry performed on a specimen.
Since Medicare does not pay for duplicate testing, do not report flow cytometry on
multiple specimens on the same date of service unless the morphology or other clinical factors suggest
differing results on the different specimens.
There is no CPT code for interpretation of one marker.
The provider should not bill for interpretation of a single marker using another CPT
Quantitative cell counts performed by flow cytometry (CPT codes 86064, 86359-86361,
86379, and 86587) should not be reported with the flow cytometry interpretation CPT codes 88187-88189
since there is no interpretative service for these quantitative cell counts.
Interpretation and report associated with molecular diagnostic testing
15. CPT code 83912 is reported to describe a medically reasonable and necessary
"interpretation and report" associated with molecular diagnostic testing described with CPT codes
CPT code 83912 should not be reported as an "interpretation and report" with CPT
codes 87470-87801, 87901-87904 or 88271-88275.