ICD-10 Code M00.18 – Pneumococcal arthritis, vertebrae (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M00.18 – Pneumococcal arthritis, vertebrae
What it is
M00.18 identifies a pneumococcal infection causing septic arthritis in the vertebrae. Use it when Streptococcus pneumoniae is documented as the organism and the vertebral joint or spine is the infected site.
Clinical signs
Typical findings include localized spinal pain, tenderness, reduced motion, and signs of acute joint infection. Clinical features vary; refer to documentation for confirmed vertebral involvement and pneumococcal cause.
When to use this code
Use M00.18 when the record clearly states pneumococcal arthritis affecting the vertebrae, or a clinician documents septic arthritis of the spine due to Streptococcus pneumoniae. Code the site-specific diagnosis rather than a nonspecific arthritis code.
If the organism is not identified, or the affected site is different, this code is not appropriate. Check documentation for laterality, exact joint site, and confirmed infectious cause before assigning the code.
Do not use for
Do not use this code for noninfectious arthritis, vertebral osteomyelitis without arthritis, or septic arthritis caused by another organism. Check documentation if the spinal site or pathogen is unclear.
Coding tip
Verify both the organism and the vertebral joint site in the provider note before coding M00.18.