Both seasoned and new coding professionals know that the assignment of combination codes can be very tricky at times. It is imperative that the ICD-9-CM index be utilized to arrive at accurate codes, including combination codes. In addition, all includes and exclude notes must be referenced and followed. In this issue of CCS Prep! we will present some guidelines to follow in the assignment of these codes. In addition, a short quiz is provided to test your knowledge of combination code assignment.
1. In "The Official Coding Guidelines for Coding and Reporting," developed and approved by the four cooperating parties, combination code assignment is addressed in guideline 1.5. This guideline reads: "A single code used to classify two diagnoses or a diagnosis with an associated secondary process (manifestation) or an associated complication is called a combination code. Combination codes are identified by referring to subterm entries in the Alphabetic Index and by reading the inclusion and exclusion notes in the Tabular List. Assign only the combination code when that code fully identifies the diagnostic conditions involved or when the Alphabetic Index so directs. Multiple coding should not be used when the classification provides a combination code that clearly identifies all of the elements documented in the diagnosis. When the combination code lacks necessary specificity in describing the manifestation or complication, an additional code may be used as a secondary code."
2. Official guideline 1.6 addresses multiple coding of diagnoses required for certain conditions not subject to the rules for combination codes. "Instructions for conditions that require multiple coding appear in the Alphabetic Index and the Tabular List.
A. Alphabetic Index: Codes for both etiology and manifestation of a disease appear following the subentry term, with the second code in brackets. Assign both codes in the same sequence in which they appear in the Alphabetic Index.
B. Tabular List: Instructional terms, such as "Code first...," "Use additional code for any...," and "Note...," indicate when to use more than one code.
Code first underlying disease: Assign the codes for both the manifestation and underlying cause. The codes for manifestations cannot be used (designated) as a principal diagnosis.
'Use additional code, to identify manifestation, as ...': Assign also the code that identifies the manifestation, such as, but not limited to, the examples listed. The codes for manifestations cannot be used (designated) as principal diagnosis.
C. Apply multiple coding instructions throughout the classification where appropriate, whether or not multiple coding directions appear in the Alphabetic Index or the Tabular List. Avoid indiscriminate multiple coding or irrelevant information, such as symptoms or signs characteristic of the diagnosis."
3. Be alert to subterms that follow connecting words such as "with," "in," "due to" and "associated with."
4. Combination codes may not fully describe the condition, and additional codes may be necessary. For example, urinary tract infection complicating pregnancy codes to 646.6X. The additional code of 599.0 is needed to fully describe the condition. Refer to the note listed under category 646. "Use additional code(s) to further specify condition."
5. Several Coding Clinic issues address combination coding. They are issues 1986 January-February pp. 1, 8-10; 1985 March-April p. 3; 1984 May-June pp. 1-8; 1986 Sept-Oct pp. 5-9 for fractures; 1990 Third Quarter p. 5 and 1992 Fourth Quarter pp. 22-23 for hypertension and heart/renal disease combinations; 1991 Second Quarter p. 10 for drug abuse/dependence coding; 1992 Second Quarter pp. 8-9 for GI bleeding and condition combinations; 1993 Fourth Quarter pp. 26-28; 1993 Fifth issue p. 5; 1995 Third Quarter p. 5; 1995 Fourth Quarter p. 60 for vertebrobasilar artery syndrome; 1998 Fourth Quarter pp. 39-40, 88-89; 1999 Second Quarter p. 16 for UTI coding; 1999 Fourth Quarter pp. 3-4 for CVA with residuals.
Some of the codes used for examples may have changed due to later code revisions. Be sure to check the latest ICD-9-CM codebook for updates to these codes.
6. Perhaps the chapter with the most difficult combination code scenarios is the cardiovascular and renal chapters. Many combination code scenarios in these chapters are dependent on the full clinical information presented within the record. Review alphabetic index, tabular and all notes regarding the coding of rheumatic heart diseases, hypertension with renal disease and/or congestive heart failure, arteriosclerosis of extremities with symptoms and cerebral infarctions. In addition, review the Coding Clinics listed above that address hypertension and combination code use with conditions involving renal failure and cardiovascular conditions. Also, review Official Coding Guideline 4.2 through 4.6 for complete official instruction on these conditions.
Take the following quiz to test your combination code knowledge.
A) Acute cholecystitis with cholelithiasis and choledocholithiasis:
1. 574.00, 574.50
3. 575.0, 574.20, 574.50
B) Meningitis due to salmonella infection:
2. 321.8, 003.21
C) Increased episcleral venous pressure due to glaucoma:
2. 365.9, 365.00
D) Hypertensive heart disease with congestive heart failure:
2. 428.0, 401.9
E) Congestive heart failure with hypertension:
2. 428.0, 401.9
F) Hypertensive cardiomegaly
1. 429.3, 401.9
2. 429.3, 402.90
G) Hypertensive nephropathy with congestive heart failure:
3. 402.91, 593.9
2. 401.9, 593.9
I) Mitral valve stenosis and aortic valve insufficiency:
1. 424.0, 424.1
J) Mitral valve stenosis with congestive heart failure:
1. 424.0, 428.0
2. 394.0, 398.91
3. 394.0, 428.0
K) Drug dependence on marijuana and cocaine, continual:
2. 304.21, 304.31
L) Conduct disorder secondary to benzedrine dependence:
1. 312.9, 304.40
M) Acute appendicitis with peritoneal abscess and generalized appendicitis:
2. 540.0, 567.2
N) Urinary tract infection due to candidiasis:
2. 112.2, 599.0
Patricia Maccariella-Hafey is director of education for Health Information Associates Inc., a company specializing in providing contract coding and coding compliance review services for hospitals. The corporate office is headquartered in Pawley's Island, SC.
A) 2- 574.60
B) 1- 003.21
C) 3- 365.82
D) 1- 402.91
E) 2- 428.0, 401.9 (This is not considered hypertensive heart failure. The "with" does not denote hypertensive.)
F) 3- 402.90
G) 2- 404.91 (Nephropathy is considered renal disease per text under 403.XX)
H) 1- 403.90
I) 3- 396.1
J) 2- 394.0, 398.91
K) 1- 304.81
L) 2- 304.40 (See excludes notes under 312.9; drug dependence is excluded so not coded when due to drug dependence.) Terms following the word excludes are to be coded elsewhere as indicated in each case
M) 3- 540.1