Q&A: Determining whether identifying a causative organism adds a CC/MCC

Q: I’ve heard some conflicting advice regarding code group B95-B97, bacterial and viral infectious agents. I’ve heard that those codes don’t provide a CC or MCC as a secondary diagnosis in most cases. I’ve also heard that identification of the causative organism often does add a CC/MCC or affects the severity of illness (SOI)/risk of mortality (ROM). Could you clarify this for me?

A: In a way, both advice is true. Anytime you have an infection, whether it’s localized or systemic, it’s important to see if the provider can identify the organism because it could increase a patients SOI/ROM when using the APR-DRG system or it could capture a CC/MCC. However, this is not a guarantee.  

When the type of infection is not identified as part of the infectious disease chapter (for example, acute sinusitis, which is a respiratory diagnosis) you will see a “code also” note that instructs the coder to use the codes B95, B96, or B97 to identify the organism. In ICD-10-CM we have a lot of combination codes. When used, they identify both the patient’s condition and the causative organism. When appropriate, the combination code should be used instead of using two separate codes to identify the condition and the organism.

In these cases, whether a combination code is used or two separate codes, it could result in the capture of either a CC/MCC and also increase the patient’s SOI/ROM. But, like I said before, that’s not a guarantee. Usually, when an “unspecified” code is used and no further specificity is available, we could often lose the CC/MCC.

Editor’s Note: Sharme Brodie RN, CCDS, CDI education specialist and CDI Boot Camp instructor for HCPro in Middleton, Massachusetts, answered this question. For information, contact her at sbrodie@hcpro.com. For information regarding CDI Boot Camps offered by HCPro, visit www.hcprobootcamps.com/courses/10040/overview.