Part 2: Specificity Coding of Acute Kidney Injury (AKI) and Sequencing | AKI Series
Kim Carrier RHIT, CDIP, CCS, CCS-P
Director of Coding Quality Assurance
AHIMA Approved ICD-10-CM/PCS Trainer
As discussed in Part 1 of this series, AKI/ARF is a common diagnosis that coders see daily. In Part 2, we are going to focus on the different types/specificity of AKI/ARF. We’ll learn what they mean, as well as how to code the diagnosis.
There are several different codes that can be used to report the diagnosis of acute kidney injury and/or acute renal failure. This is one example of why diagnoses should not be coded by the use of only the Alphabetic Index within ICD-10-CM. It is imperative that coders also use the tabular before final determination of the code is made. If the coder only looks in the Alphabetic Index under injury | kidney | acute, the index goes to N17.9 (acute renal kidney failure, unspecified). If the type or cause of the AKI/ARF is further specified then N17.9 would not be appropriate. However, if the coder begins the search with the term “failure” there will be several selections for further specificity under failure | renal | acute.
When coding AKI/ARF, there are instructional notes within the ICD-10-CM Index for coders to follow as well as Exclude1 and Excludes2 notes. When a cause for the AKI/ARF has been identified the underlying condition/cause should be reported also. Traumatic kidney injuries are reported with codes from S37.0-.
- N17.0—Acute kidney failure with tubular necrosis. Coders see ATN (acute tubular necrosis) documented in patient records often. This is a common diagnosis that a query is necessary for clarification. If the AKI has progressed to ATN then the code N17.0 is reported and not the code default in the Alphabetic Index for AKI. Other terms that may be used to describe ATN could be renal tubular necrosis or tubular necrosis. These are terms that should be searched for when AKI is documented to see if there could be further specificity in code assignment. ATN occurs when there is damage to the kidney tubule cells. These are the cells that reabsorb fluid and minerals in the kidney from urine as it is forming. When this occurs, there is a lack of oxygen reaching the cells of your kidneys.
- N17.1—Acute kidney failure with acute cortical necrosis. This isn’t as commonly documented as ATN but coders will see this. If the AKI has progressed to acute cortical necrosis then N17.1 is reported and not the code default in the Alphabetic Index for AKI. Other terms that may be used to describe acute cortical necrosis can be cortical necrosis and renal cortical necrosis. This is a rare cause of AKI and is due to ischemic necrosis of the renal cortex. This is typically caused by diminished/reduced renal arterial perfusion. Intravascular coagulation, vascular spasm and microvascular injury are the main causes of this type of AKI.
- N17.2—Acute kidney failure with medullary necrosis This isn’t as commonly documented as ATN but coders will see this. if the AKI has progressed to with medullary necrosis then N17.2 is reported and not the code default in the Alphabetic Index for AKI. Other terms that may be used to describe acute medullary necrosis can be acute medullary [papillary] necrosis or renal medullary necrosis. This is caused by infarction involving the medulla and referred to as necrotizing papillitis.
- N17.8—Other acute kidney failure. This code is reported when there is a specificity to the diagnosis of AKI (non-traumatic) but is not one of the ones above.
- N17.9—Acute kidney failure, unspecified. This code is reported when only AKI/ARF is documented without any further specificity documented.
Sequencing of AKI/ARF
There are many different scenarios that would dictate the sequencing of AKI/ARF. The definition of PDX should always be used when determining the PDX. Remember that just because the condition may be present on admission does not necessarily mean that it is appropriate as PDX. Chapter specific guideline must be followed as well as other coding guidance that your record may require. Some of the most common specific guidelines that come to mind are sepsis, OB/delivery records and transplant complications. Let’s look at an example of each of these:
- Just in my experience, I think sepsis is one of the most common conditions that are associated with a diagnosis of AKI. If a patient presents with high fever, elevated WBC of 20,000, altered mental status. Labs show that the patient has AKI based on elevated creatinine of 4.3 that is way above the baseline for this patient and they are admitted for workup and treatment. This was a complicated stay with several physicians documenting daily. The fever and elevated WBC count is documented to be caused by sepsis. The AKI is further documented as ATN due to sepsis and there is no contradictory documentation that requires a query. The creatinine on discharge had improved to 1.1 which is the patient’s baseline. In this case, ATN would NOT be appropriate as the PDX since it is related to sepsis. There are specific guidelines that state to code the systemic infection first and then any organ dysfunction associated with the diagnosis. Sepsis would be the PDX in this case followed by severe sepsis without shock and ATN as additional SDX codes.
- Patient presents for emergency cesarean section due to heavy bleeding and suspicion of placenta abruption. She is 38 weeks pregnant. Patient does undergo the cesarean without complication other than blood loss. The abruption of the placenta is confirmed. Due to blood loss, the patient is watched closely and is noted to develop AKI/ARF on day two post discharge. This is addressed quickly with IV fluids and the patient does improve over the next few days. Her labs are better each day and the decision of discharge was made. In this case, the AKI/ARF would not be the PDX for two reasons: 1) It occurred after surgery/cesarean, and 2) OB guidelines would be followed and a code from Chapter 15 would be reported as codes from this chapter always take sequencing priority. A code from Chapter 15 for the AKI/ARF would be reported. No additional code for the AKI/ARF would be necessary since this is not further specified and the unspecified code does not provide any further specificity. Other codes for the weeks of gestation and single live birth would be reported as well as ICD-10-PCS for the cesarean.
- Patient presents with generally feeling unwell. They are four months s/p renal transplant that has been doing well during follow up visits. The patient states that she developed a virus a few days ago and has not been able to keep anything on her stomach for three days now. Patient is admitted due to symptoms and to monitor the kidney transplant status. The labs do show that the patient has AKI/ARF with creatinine extremely high at 6.1. The baseline creatinine for this patient since transplant has been 1.1-1.4. Aggressive treatment is begun and the labs show complete improvement in only 2 days of aggressive fluids. The diagnosis from the physician is AKI/ARF in a kidney transplant patient with recovery of full function by discharge. In this case, the AKI/ARF would not be appropriate as the PDX since the function of the transplanted kidney was impaired. Per recent coding guidance, this is coded as T86.19—other complication of kidney transplant and not T86.12—Kidney transplant failure since only the function of the organ was affected but the transplant has not truly failed.
Note: The old sequencing guidance from ICD-9-CM regarding AKI/ARF and dehydration has been clarified in 2019. The sequencing is based on the circumstances of admission and will be a case by case decision. There is no rule that states that the AKI/ARF must be sequenced first over dehydration.
ICD-10-CM Alphabetic and Tabular Indexes
ICD-10-CM/PCS Coding Clinic, First Quarter 2019 Page: 12
ICD-10-CM/PCS Coding Clinic, Second Quarter 2019 Page: 7
ICD-10-CM Official Guidelines for Coding and Reporting FY 2020
The information contained in this coding advice is valid at the time of posting. Viewers are encouraged to research subsequent official guidance in the areas associated with the topic as they can change rapidly.
Assign code Z20.828, “Contact with and (suspected) exposure to other viral communicable diseases” for all patients who are tested for COVID-19 and the results are negative, regardless of symptoms, no symptoms, exposure or not as we are in a pandemic.
The Centers for Medicare & Medicaid Services (CMS) announced new procedure codes for treatments of COVID-19 – effective as of August 1, 2020. Among the new codes are Section X New Technology codes for the introduction or infusion of therapeutics including Remdesivir, Sarilumab, Tocilizumab, transfusion of convalescent plasma, as well as introduction of any other or new therapeutic substances for the treatment of COVID-19.
One common element in many value-based programs is risk adjustment using Hierarchical Condition Categories (HCCs) to create a Risk Adjustment Factor (RAF) score. This method ranks diagnoses into categories that represent conditions with similar cost patterns.
Why are so many AKI records being denied? It’s hard to give one answer for why so many AKI records are being denied lately, but most appear to be due to the multiple sets of criteria available for use in determining if a patient has AKI, as well as physician documentation. As stated in Part 3 of this series, there are three main criteria/classifications used to diagnose AKI.
In previous parts of this series we looked at the definitions of AKI/ARF, causes, coding and sequencing, and the common clinical indicators that patients present with that are diagnosed with this condition. In Part 4, we will look at the documentation that should be present to report the diagnosis without fear of denial, as well as when a query is needed to clarify the diagnosis.
If the facility does a COVID-19 test, and test is negative, do I need a diagnosis code. The answer is yes, you will report a Z-code. The Z-code depends on the record documentation and circumstances of testing. For any patient receiving a COVID-19 test, if negative, there MUST e a Z-code to describe why the test was taken. (Test negative for COVID-19 and MD does not override negative results).
In the first parts of this series we looked at definitions of AKI/ARF, causes, coding and sequencing. In Part 3, we will look at what clinical indicators would possibly be present to support the diagnosis of AKI/ARF.
The FY2021 IPPS Proposed Rule is out and here are some highlights from it regarding ICD-10 Code proposals. We will know if these changes are permanent after the public comment period is over on July 10, 2020 and CMS prepares the Final Rule, usually out by August 1.
This is part 1 in a series focused on coding of acute kidney injury (AKI) and/or acute renal failure (ARF). AKI/ARF is reported often, but is also one of the most common diagnosis found in denials.
With the proliferation of COVID-19 cases, we thought we would put together a quick reference listing of some of the common scenarios that coders have asked about. As with all coding, coders should follow Official Guidelines for Coding and Reporting and the COVD-19 Frequently Asked Questions document by the AHA.
Effective March 1, Medicare will pay physicians for telehealth services at the same rate as in-person visits for all diagnoses, not just services related to COVID-19. This great for providers whose patients are reluctant to visit the office.
The biggest reasons why some hospital systems are moving to single path coding is to eliminate duplicative processes and to optimize productivity. In addition, costs are reduced when only one coder “touches” the record and completes both types of coding.
Effective with 4/1/2020 discharges, ICD-10-CM code U07.0 is used to report vaping -related disorders. ICD-10-CM code U07.0 (vaping related disorder) should be used when documentation supports that the patient has a lung-related disorder from vaping. This code is found in the new ICD-10-CM Chapter 22. U07.0 will be in listed in the ICD-10-CM manual under a new section: Provisional assignment of new disease of uncertain etiology or emergency use.
The US government and public-health officials are urging consumers to utilize telemedicine for remote treatment, fill prescriptions and get medical attention during the new coronavirus pandemic. The goal is to keep people with symptoms at home and to practice social distancing if their condition doesn’t warrant more intensive hospital care.
Coronavirus: Tips for working from home. Companies around the world have told their employees to stay home and work remotely. Whether you’re a new to this concept or a work from home veteran, here’s some tips to staying productive from our #HIAfamily.
This is the final part of a three part series in which we address how coders can better interact with Clinical Documentation Improvement (CDI) professionals. In this part, we provide an actual example of an effective communication response to CDI.
This is part two of a three part series in which we address how coders can better interact with Clinical Documentation Improvement (CDI) professionals. In this part, we discuss mismatches and how to best go about resolving them. In part three we will provide a case example of best practice interaction.
This is part one of a three part series in which we address how coders can better interact with Clinical Documentation Integrity (CDI) professionals. Many times these departments are separate and the remote environment makes it difficult to interact efficiently between the two departments. In part one, we will discuss the history and objectives of CDI so the coder has a better understanding of CDI’s role.
One reason that coders should report chronic conditions (including history and status codes) on outpatient records is the HCC’s—Hierarchical Condition Categories. The quick and easy explanation of what HCC’s are is each HCC is mapped to certain ICD-10-CM codes or code ranges. HCC coding is designed to estimate future health care costs for patients.
For Part 5 of this 5-part series, we will look at Chapter 4 within ICD-10-CM—E00-E89—Endocrine, Nutritional, and Metabolic Diseases. There is no possible way to include every guideline or coding reference for this chapter, but here are some of the most common issues.
For Part 4 of this 5-part series, we will look at Chapter 10 within ICD-10-CM—J00-J99—Diseases of the Respiratory System. There is no possible way to include every guideline or coding reference for this chapter, but here are some of the most common issues.
For Part 3 of this 5 part series, we will look at Chapter 9 within ICD-10-CM—I00-I99—Diseases of the Circulatory System. This chapter contains so many of the everyday diagnoses that we code such as hypertension, heart disease and stroke.
For Part 2 of this 5-part series, we will look at Chapter 1 within ICD-10-CM—A00-B99—Certain Infectious and Parasitic Diseases. There is no possible way to include every guideline or coding reference for this chapter, but here are some of the most common issues.
The HIM world has been buzzing recently with discussion of “Social Determinants of Health” and coded data. What does this mean for coders and the HIM field?
In response to the recent occurrences of vaping related disorders and in consultation with the World Health Organization (WHO) Framework Convention on Tobacco Control, the WHO Family of International Classifications (WHOFIC) Network Classification and Statistics Advisory Committee (CSAC) was convened to discuss a diagnosis code for vaping related illness for immediate use.
The Centers for Disease Control and Prevention (CDC) is in process of developing a new code for the COVID-19 (coronavirus) that will be released October 1, 2020. In the meantime, the CDC has provided advice on coding the COVID-19 coronavirus.
We’re finally at the #1 most common DRG with recommendations by HIA for 2019. Just to recap, HIA reviewed over 50,000 inpatient records in 2019. Most have probably already guessed what the correct DRG would be with the most recommendations. There are just some diagnoses and DRG’s that will always be a thorn in the side for coders. #1 DRG with the most recommendations during HIA reviews : DRG 871—Septicemia or severe sepsis w/o mechanical ventilation >96 hours with MCC
We’re now at the second most common DRG with recommendations by HIA for 2019. Just to recap, HIA reviewed over 50,000 inpatient records in 2019. We are counting down to # 1. #2 DRG with the most recommendations during HIA reviews: DRG 872—Septicemia or severe sepsis w/o mechanical ventilation >96 hours w/o MCC.
In 2019, HIA reviewed over 50,000 inpatient records. Wow! That is a lot of records. Even with this large number of records, the DRG’s with recommendations are still the ones that coders typically see during audits. #3 DRG 190—Chronic obstructive pulmonary disease with MCC.