Hepatitis B coinfection: HBsAg positive OR anti-HBc total positive (occult HBV risk). HCV...

Deterministic view of the source YAML entity. Clinical authority remains with the cited source IDs and reviewer sign-off state.

ID	`RF-HBV-COINFECTION`
Type	Red flag
Status	reviewed 2026-04-25 \| pending_clinical_signoff
Diseases	`DIS-HCV-MZL`
Sources	`SRC-EASL-HCV-2023` `SRC-NCCN-BCELL-2025`

Red Flag Origin

Definition	Hepatitis B coinfection: HBsAg positive OR anti-HBc total positive (occult HBV risk). HCV-MZL-specific surveillance flag — universal HBV reactivation handling lives in RF-UNIVERSAL-HBV-REACTIVATION-RISK.
Clinical direction	investigate
Category	infection-screening

Trigger Logic

{
  "any_of": [
    {
      "finding": "hbsag",
      "value": "positive"
    },
    {
      "finding": "anti_hbc_total",
      "value": "positive"
    }
  ],
  "type": "lab_value"
}

Notes

HBV co-infection in HCV-MZL patients triggers MDT-brief annotation recommending HBV-prophylaxis (entecavir or TDF) before any anti-CD20 exposure. Reactivation rates without prophylaxis: ~50% in HBsAg+, 5-10% in anti-HBc+ (occult HBV). Algorithm choice between ANTIVIRAL and BR-AGGRESSIVE arms is not affected — both arms can proceed with HBV prophylaxis in parallel. The cross-disease/universal HBV reactivation handling (HBsAg+, anti-HBc+, HBV-DNA detectable) is consolidated into RF-UNIVERSAL-HBV-REACTIVATION-RISK. This disease-specific entry kept for backwards compatibility with existing HCV-MZL plans; new diseases should rely on the universal flag instead.

Used By

Biomarker

BIO-HBV-STATUS - HBV status (HBsAg + anti-HBc serology)

Contraindications

CI-HBV-NO-PROPHYLAXIS - CI-HBV-NO-PROPHYLAXIS

Questionnaires

QUEST-CLL-1L - Chronic Lymphocytic Leukemia / SLL — first line
QUEST-HCV-MZL-1L - HCV-associated Marginal Zone Lymphoma — first line
QUEST-MM-1L - Multiple Myeloma — newly diagnosed (1L)

Red flag

RF-UNIVERSAL-HBV-REACTIVATION-RISK - Risk of HBV reactivation prior to immunosuppressive / cytotoxic therapy: HBsAg-positive (...