by Bonnie Schreck
February 29th, 2016
Bones are typically resistant to bacterial colonization, but events such as trauma, surgery, the presence of foreign bodies, or the placement of prostheses may disrupt bony integrity, or a result of a spread after bacteremia, and lead to the onset of bone infection caused by an infectious organism, or osteomyelitis. In ICD-10-CM, osteomyelitis is differentiated as acute, subacute, or chronic. A subacute infection is differentiated from an acute infection and has its own subcategories.
Acute osteomyelitis develops rapidly during the course of several days. It is characterized by localized pain, soft tissue swelling and tissue warmth at the site of the infection, with symptoms such as fever, fatigue, and nausea. There are two subcategories for reporting acute osteomyelitis, including M86.0 Acute hematogenous osteomyelitis, and M86.1 Other acute osteomyelitis. Acute hematogenous osteomyelitis results from an infection at a remote site, then the infectious organism is carried through the bloodstream to the bone. The most common infectious organism is Staphylococcus aureus. Acute osteomyelitis also may result from the infectious organism from an open wound, an open fracture, or an invasive surgical procedure. Direct inoculation osteomyelitis is reported with codes from subcategory M86.1.
Subacute osteomyelitis is differentiated from acute osteomyelitis, with a slower onset of symptoms and a diminished degree of severity of the symptoms, which may include only moderate, localized pain without any systemic issues. This is reported with M86.2 Subacute osteomyelitis.
Chronic osteomyelitis is a persistent infection that may be severe, which can reoccur and be difficult to treat. It also may present with a draining sinus tract that drains through the skin surface, presenting a greater risk for complications, such as major bone defects.
There are four subcategories in ICD-10-CM for chronic osteomyelitis: M86.3 Chronic multifocal osteomyelitis; M86.4 Chronic osteomyelitis with draining sinus; M86.5 Other chronic hematogenous osteomyelitis, and M86.6 Other chronic osteomyelitis.
Chronic multifocal osteomyelitis, also called chronic recurrent multifocal osteomyelitis or SAPHO syndrome, which includes synovitis, acne, pustulosis, and hyperostosis osteitis, is a rare condition of an unknown cause. Tissue cultures typically fail to identify any infectious organism in this type of osteomyelitis. It is characterized by multiple areas of bone inflammation and may be accompanied by skin changes, including acne, psoriasis, and pustules on the palms of the hands and soles of the feet.
The other three subcategories for chronic osteomyelitis report hematogenous and direct inoculation types, with category M86.3 being a combination code that captures chronic types in which a draining sinus has developed.
Two additional subcategories for the reporting osteomyelitis are M86.8 reports other osteomyelitis, and this category includes Brodie’s abscess. Brodie’s abscess previously was classified as a type of chronic osteomyelitis, but most scholarly literature now refers to it as a sub-acute condition. The defining characteristic is the presence of a bone abscess surrounded by dense fibrous tissue and sclerotic bone. Subcategory M86.9 reports unspecified osteomyelitis.
Documentation should include the severity (acute, subacute, or chronic), the type, such as hematogenous, multifocal or with a draining sinus, and the anatomical site. Specific sites for subcategories M86.0-M86.6 include:
• Other specified sites
• Multiple sites
If only the osteomyelitis and the site is documented, the code would be M86.9 Osteomyelitis, unspecified, which does not state the site of the osteomyelitis. The physician should be queried on the severity and type in order to get the specificity necessary for code selection.
Osteomyelitis and Diabetes Mellitus
If a patient has osteomyelitis and diabetes mellitus (DM), there is not an assumed relationship between the two conditions. The physician must document a cause and effect relationship in order to code diabetic osteomyelitis using the diabetic code E10.69, Type 1 diabetes with other specified complication, or E11.69 for Type 2 diabetes with other specified complication. If no relationship is documented, code the conditions separately using the code for DM without complications, or query the physician for clarification.
An additional code from categories B95-B97 should be assigned to identify the infectious agent if it is documented. Any major osseous defects also should be identified with a code from subcategory M89.7.