Pyogenic (bacterial) infection of an intervertebral disc where the spinal region has not been documented or specified by the treating provider.

Documentation tips

What should appear in the chart to support M46.30.

Source · Editorial brief grounded in 5 cited references ↓

• Specify the spinal region by name (cervical, thoracic, lumbar, etc.) in every note so a site-specific code (M46.31–M46.39) can be used instead of the unspecified M46.30.
• Always document the causative organism when identified — culture results, blood culture reports, or biopsy pathology — and add the corresponding B95–B97 code as instructed by the ICD-10-CM Tabular List.
• Distinguish pyogenic (bacterial) from non-pyogenic discitis in the assessment: the word 'pyogenic' or documentation of a specific bacterial agent supports M46.30–M46.39 over M46.4x.
• Record imaging findings (MRI signal changes at the disc and adjacent endplates, gadolinium enhancement, CT evidence of endplate destruction) to support medical necessity for both the diagnosis and any surgical intervention.
• Document conservative treatment history (antibiotics, duration, response) prior to any surgical procedure to satisfy payer medical necessity criteria.

Related CPT procedures

Procedure codes commonly billed with M46.30. Linking the right diagnosis to the right procedure is what establishes medical necessity.

Source · CMS LCDs · AAOS specialty guidance · claims-pattern analysis

Common coding pitfalls

The recurring mistakes coders make with M46.30 and adjacent codes.

Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓

• Using M46.30 (site unspecified) when MRI or operative reports clearly identify the affected level — always assign the site-specific code (M46.31–M46.39) when level is documented.
• Confusing M46.30 with M46.4 (discitis, unspecified): M46.30 requires documented or suspected pyogenic (bacterial) etiology; M46.4x is for discitis of unknown or unspecified cause.
• Omitting the B95–B97 causative-agent code when the organism is identified — the Tabular List 'Use Additional' instruction at the M46.3 parent level makes this mandatory, not optional.
• Coding M46.30 when M46.39 (multiple sites) is correct — if imaging or the operative report describes involvement at more than one spinal level, use M46.39.
• Billing M46.30 on a claim for a spinal procedure without supporting imaging or culture documentation, which can trigger a medical necessity audit.

Clinical context

Source · Editorial summary grounded in 5 cited references ↓

Sibling codes

Other billable codes under M46.3 (laterality / anatomic variants).