July 25, 2011

Coding Symptoms, Signs and Ill-Defined Conditions Under ICD-10-CM


In preparation for conversion from ICD-9-CM to ICD-10-CM diagnosis coding, and in anticipation of the new coding system’s implementation (effective Oct. 1, 2013), providers will need to take stock of their coding patterns as well as review their internal charge capture tools (i.e. the practice superbill) to see which frequently reported ICD-9 codes they immediately will want to research within ICD-10.  Becoming familiar with the updated codes will be a pivotal step in this transition. One of the coding patterns that should be scrutinized is the frequency with which unspecified and “not otherwise specified” (NOS) codes currently are assigned appropriately. Often, as explained below, unspecified and/or NOS codes are the only options for diagnosis coding at certain levels of patient study and care.

Many of these codes, though certainly not all, are found in the ICD-9-CM chapter dedicated specifically to unconfirmed diagnoses and similar conditions; this chapter aptly is named “Symptoms, Signs and Ill-Defined Conditions.” A quick glance at the practice encounter form may be telling in this regard. Often superbills are packed with nonspecific codes to help facilitate quick, at-a-glance coding by providers on the run instead of having certified coders assign diagnosis codes from detailed, well-written medical record documentation. The latter obviously is preferred – and even mandatory, in many instances – to establish medical necessity and obtain appropriate reimbursement for services rendered.

That said, unspecified and nonspecific coding scenarios are actually commonplace in general practice, family practice and internal medicine, among other primary care specialties in which the level of evaluation and assessment may be more limited until a patient has been sent to specialists for further work-up, evaluation and treatment. Which unspecified and nonspecific codes are available for use promises to change slightly under ICD-10, however. In fact, the ICD-9-CM chapter now housing most of these codes, Chapter 16 covering “Symptoms, Signs and Ill-Defined Conditions” (code series 780 – 799), has many organizational changes under the new ICD-10-CM format, now falling under Chapter 18 and renamed “Symptoms, Signs and Abnormal Clinical and Laboratory Findings, Not Elsewhere Classified” (code series R00-R99).

Some of the codes that previously were found in body system chapters are now in this particular ICD-10-CM chapter, and the reverse is true for some ICD-9 codes that once were located in the symptoms/signs chapter and now will be located in specific ICD-10 body system chapters. For example, in ICD-9-CM “hematuria, unspecified” currently is coded to 599.70 in Chapter 10, “Diseases of the Genitourinary System” (code series 580 – 629), but in ICD-10-CM this has been moved to Chapter 18 and is included under symptoms/signs of the GU system (being coded to R31.9). Likewise, conditions such as “systemic inflammatory response syndrome” (SIRS), “severe sepsis” and “septic shock” currently found in ICD-9-CM Chapter 17, “Injury and Poisoning” (code series 800 – 999) are located in Chapter 18 under general symptoms/signs in code series R65 in ICD-10-CM – specifically, R65.10, “SIRS of non-infectious origin without acute organ dysfunction.”

Conversely (and curiously), ICD-9-CM code 785.4, representing “Gangrene NOS,” which currently is located in Chapter 16 for symptoms/signs is to be found under code I96 (eye-96) in the specific body system Chapter 9, “Diseases of the Circulatory System” (code series I00 – I99) in ICD-10-CM.

The preamble for Chapter 18, “Symptoms, Signs and Abnormal Clinical and Laboratory Findings, Not Elsewhere Classified” in the new ICD-10 coding system remains much the same as it was in ICD-9, specifying that the codes found within this range include “(a) cases for which no more specific diagnosis can be made even after all the facts bearing on the case have been investigated; (b) signs or symptoms existing at the time of initial encounter that proved to be transient and whose causes could not be determined; (c) provisional diagnosis in a patient who failed to return for further investigation or care; (d) cases referred elsewhere for investigation or treatment before the diagnosis was made; (e) cases in which a more precise diagnosis was not available for any other reason; (f) certain symptoms, for which supplementary information is provided, that represent important problems in medical care in their own right.”

In ICD-10-CM, Chapter 18, Symptoms, Signs and Abnormal Clinical and Laboratory Findings, Not Elsewhere Classified (R00-R99) has been organized into 14 blocks of codes, including:

(1) R00 – R09 Symptoms and signs involving the circulatory and respiratory systems;

(2) R10 – R19 Symptoms and signs involving the digestive system and abdomen;

(3) R20 – R23 Symptoms and signs involving the skin and subcutaneous tissue;



(4) R25 – R29 Symptoms and signs involving the nervous and musculoskeletal systems;

(5) R30 – R39 Symptoms and signs involving the urinary system;

(6) R40 – R46 Symptoms and signs involving cognition, perception, emotional state and behavior;

(7) R47 – R49 Symptoms and signs involving speech and voice;

(8) R50 – R69 General symptoms and signs;

(9) R70 – R79 Abnormal findings on examination of blood, without diagnosis;

(10) R80 – R82 Abnormal findings on examination of urine, without diagnosis;

(11) R83 – R89 Abnormal findings on examination of other body fluids, substances and tissues, without diagnosis;

(12) R90 – R94 Abnormal findings on diagnostic imaging and in function studies, without diagnosis;

(13) R97 Abnormal tumor markers; and

(14) R99 Ill-defined and unknown cause of mortality.

Providers should take steps to familiarize themselves with the new ICD-10-CM code structure, especially within the more generalized chapter of symptoms/signs and ill-defined conditions. To be apprised of these codes in thorough fashion, the practice coding and/or billing staff can run computer-generated reports for the most frequent ICD-9-CM codes now assigned and probably can “demand” reports on specific code ranges (such as those currently contained in Chapter 16 within code series 780 – 799). These new ICD-10-CM codes and their applications can be discussed and analyzed at practice staff meetings, and all practice staff with coding responsibilities can begin to become familiar with the new coding structure under ICD-10 – including the providers themselves.

If there are coding scenarios that can be more specific and/or better aligned to clinical documentation (or if clinical documentation can be more detailed to accommodate the more specific codes found in ICD-10-CM), then the transition from ICD-9 to ICD-10 will be less cumbersome. For example, correctly coding “RUQ rebound abdominal tenderness” will require detailed clinical documentation and familiarity with new coding classifications in ICD-10-CM. Rebound tenderness and nonspecific “abdominal tenderness,” which in ICD-9 both are coded to 789.6x, each have a separate code classification in ICD-10-CM, with rebound tenderness being classified to R10.82x and abdominal tenderness (without rebound) being classified to R10.81x.

With some advance planning, attention to detail in clinical documentation and a willingness to learn, the conversion of ICD-9 to ICD-10 actually can be an enlightening experience.

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Read 148 times Updated on September 23, 2013
Michael Calahan, PA, MBA

Michael G. Calahan, PA, MBA, is the vice president of hospital and physician compliance for HealthCare Consulting Solutions (HCS). Michael lives and works in the Washington, D.C. metro area, specializing in compliance, revenue cycle management, CDI, and coding/billing in the facility inpatient/outpatient and physician arenas.