ICD-10-CM 2027
ICD-10 code for Chinese liver fluke disease
From the official ICD-10-CM alphabetic index entry “Disease, diseased › Chinese liver fluke”. Page updated September 29, 2026.
About coding Chinese liver fluke disease
The ICD-10-CM code for Chinese liver fluke disease is B66.1 (Clonorchiasis).
Within B66 (other fluke infections), B66.1 is specifically for Clonorchiasis. Related codes cover Opisthorchiasis (B66.0), Dicroceliasis (B66.2), Fascioliasis (B66.3), Paragonimiasis (B66.4), Fasciolopsiasis (B66.5), other specified fluke infections (B66.8) and fluke infection, unspecified (B66.9).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
In MS-DRG v44.0, it is part of the grouping logic for DRG 441 (Disorders of Liver Except Malignancy, Cirrhosis or Alcoholic Hepatitis with MCC, relative weight 1.8219), DRG 442 (Disorders of Liver Except Malignancy, Cirrhosis or Alcoholic Hepatitis with CC, relative weight 0.9602) and DRG 443 (Disorders of Liver Except Malignancy, Cirrhosis or Alcoholic Hepatitis without CC/MCC, relative weight 0.6885), in MDC 07 (Diseases and Disorders of the Hepatobiliary System and Pancreas), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
Common questions about Chinese liver fluke disease ICD-10 codes
What is the ICD-10 code for Chinese liver fluke disease?
- B66.1 — Clonorchiasis.
Is B66.1 billable?
- Yes. B66.1 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can B66.1 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict B66.1 as a principal diagnosis.
Is B66.1 a CC or MCC?
- B66.1 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.