B66.0 Opisthorchiasis

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis.

Applicable to

• Infection due to cat liver fluke
• Infection due to Opisthorchis (felineus)(viverrini)

MS-DRG index

Defines the logic of DRG(s) 441-443 in MDC 07.

Approximate ICD-9-CM (GEMs)

• 121.0 Opisthorchiasis

Code annotations containing back-references to B66.0

Back-references to B66

• Code First: H94.0 Acoustic neuritis in infectious and parasitic diseases classified elsewhere ("parasitic disease (B65-B89)")
• Type 2 Excludes: J82 Pulmonary eosinophilia, not elsewhere classified ("pulmonary eosinophilia due to specified parasitic infection (B50-B83)")

Diagnosis Index entries for B66.0

• Infection, infected, infective (opportunistic) › cat liver fluke
• Infection, infected, infective (opportunistic) › Opisthorchis (felineus) (viverrini)
• Infestation › cat liver fluke
• Infestation › fluke › cat liver
• Infestation › fluke › liver (sheep) › cat
• Infestation › Opisthorchis (felineus) (viverrini)
• Opisthorchiasis (felineus) (viverrini)

Nearby codes

• B66 Other fluke infections
• B66.0 Opisthorchiasis (this code)
• B66.1 Clonorchiasis
• B66.2 Dicroceliasis
• B66.3 Fascioliasis
• B66.4 Paragonimiasis
• B66.5 Fasciolopsiasis