Interpretation of Infectious Disease Test Results for Organ Donation Eligibility

Hepatitis B Testing Interpretation

• The American Society of Transplantation recommends that a positive Hepatitis B Core Total Antibody (anti-HBc) result indicates previous exposure to HBV, which could represent resolved infection with immunity, false-positive result, occult chronic infection, or resolving acute infection 1, 2
• A positive Hepatitis B Surface Antibody (anti-HBs) Quantitative result (≥10 IU/mL) indicates immunity to HBV, either from vaccination or resolved infection, as recommended by the American Association for the Study of Liver Diseases 1, 2
• A positive Hepatitis B Surface Antigen (HBsAg) result indicates active HBV infection and generally contraindicates donation except for HBsAg-positive recipients or those with protective immunity, according to the Centers for Disease Control and Prevention 3, 4

HBV Status Interpretation Table

Other Infectious Disease Tests

• A positive Quantiferon Test for Latent TB result indicates latent tuberculosis infection, which does not contraindicate donation but requires recipient treatment, as recommended by the Infectious Diseases Society of America 3, 4
• A positive CMV IgG result indicates prior CMV infection, which is not a contraindication but essential for determining post-transplant prophylaxis strategy, according to the American Society of Transplantation 3, 4
• A positive Hepatitis C Antibody result indicates HCV exposure and generally contraindicates donation except for HCV-positive recipients or in emergency situations, as recommended by the American Association for the Study of Liver Diseases 3, 5
• A positive HIV Antigen/Antibody Screen result indicates HIV infection and generally contraindicates donation except for HIV-positive recipients in certain jurisdictions, according to the Centers for Disease Control and Prevention 3, 4

Impact on Organ Donation Eligibility

• Organs from donors with certain infections may still be used with appropriate recipient matching and prophylaxis strategies, as recommended by the Organ Procurement and Transplantation Network 3, 4
• HBsAg-positive organs may be considered for HBsAg-positive recipients or those with protective immunity (anti-HBs ≥10 IU/mL), according to the American Society of Transplantation 3, 5
• HCV-positive organs are generally used only for HCV-positive recipients or in emergency situations, as recommended by the American Association for the Study of Liver Diseases 5

Clinical Pitfalls and Considerations

• False-negative results may occur due to hemodilution from transfusions or infusions; testing should ideally use pre-transfusion samples, as recommended by the Centers for Disease Control and Prevention 6
• Window period infections may be missed by antibody testing alone; nucleic acid testing (NAT) reduces this risk for HIV, HBV, and HCV, according to the Infectious Diseases Society of America 5, 7
• Recipient prophylaxis and monitoring strategies should be tailored based on donor and recipient infection status, as recommended by the American Society of Transplantation 3, 5

Organ Donation and Hepatitis Infection

Hepatitis B Virus (HBV) Donors

• The American Society of Transplantation explicitly states that HBV-positive donors should be considered for donation to safely expand the organ pool 8, 9, 10
• HBsAg-positive organs are contraindicated for general use but can be considered for specific recipients, including HBsAg-positive recipients, recipients with protective immunity, and in life-threatening situations in HBV hyperendemic regions 11
• When HBsAg-positive organs are used, mandatory prophylaxis includes hepatitis B immunoglobulin (HBIg) plus antiviral agents, and close post-transplant monitoring for HBV acquisition is required 11
• Anti-HBc positive, HBsAg-negative donors are not contraindicated but require antiviral prophylaxis for liver transplant recipients and HBV non-immune recipients 11

Hepatitis C Virus (HCV) Donors

• HCV-positive organs are contraindicated for general use but considered for HCV-positive recipients and in emergency/life-threatening situations 11, 12, 13, 14
• HCV transmission occurs in 96% of recipients from HCV RNA-positive donors, but graft and patient survival at 3.5 years are not significantly different compared to HCV-negative donors 13, 14, 15
• For HCV-positive recipients with end-stage renal disease, transplantation is not contraindicated and is actually recommended, with survival being better after transplantation than remaining on dialysis 12, 13, 14, 15

Hepatitis A and E Viruses

• HAV and HEV infections are not a contraindication for transplantation except in cases of acute infection in the donor 11

Critical Screening Requirements

• All potential donors must be screened for HBsAg, anti-HBc, HCV antibody, and HIV antibody/antigen 11
• HCV serology may be negative despite active infection; HCV-RNA monitoring is essential in at-risk recipients 13, 15

Post-Transplant Monitoring Strategy

• Essential to define prophylactic strategy based on donor-recipient serology matching, with close laboratory monitoring required for acquired HBV or HCV 11
• The key principle is risk-stratified matching: organs from hepatitis-positive donors can be safely used when matched to appropriate recipients with proper prophylaxis and monitoring protocols 11, 8, 9

Guidelines for Using Anti‑HBc‑Positive Donors in Kidney Transplantation

Consensus Recommendations

• The American Society of Transplantation consensus guidelines endorse the use of HBV‑positive donors, including those who are anti‑HBc total positive, to safely expand the kidney donor pool. 16

Transmission Risk Data

• In a pooled review of 1,385 HBsAg‑negative kidney recipients receiving kidneys from anti‑HBc‑positive donors, the incidence of de novo HBsAg positivity was 0.28 % (4/1385) with no cases of symptomatic hepatitis. 16
• Patient survival and graft function were not inferior in recipients who acquired HBsAg or demonstrated anti‑HBs/anti‑HBc seroconversion compared with those who did not. 16
• Analysis of the UNOS national database showed that the annual rate of HBsAg acquisition was 0.001 cases/year from anti‑HBc‑positive donors versus 0.003 cases/year from anti‑HBc‑negative donors, indicating comparable risk. 17

Recipient Risk Stratification

Immune Recipients (anti‑HBs + or prior HBV exposure)

• Clinical hepatitis has not been reported in immunized recipients after transplantation of anti‑HBc‑positive kidneys, likely due to vaccine‑derived protection. 17
• No antiviral prophylaxis is required for immune recipients; transplantation can proceed safely. 18

HBV‑Naïve Recipients (no prior exposure or vaccination)

• Pre‑transplant HBV vaccination targeting anti‑HBs titers > 10 IU/L provides protective immunity for recipients of anti‑HBc‑positive kidneys. 17
• Higher anti‑HBs titers confer greater protection: seroconversion risk was 4 % when anti‑HBs > 100 IU/L versus 10 % when anti‑HBs < 100 IU/L. 17
• In an observational cohort of 46 kidney recipients from anti‑HBc‑positive donors, no HBV transmission occurred over a median follow‑up of 36 months when non‑immune recipients received lamivudine for 1 year. 17

Management Algorithm

Donor Evaluation

• Verify that the donor is HBsAg‑negative and anti‑HBc total positive. 19
• Testing donor anti‑HBs status is optional and does not alter transmission risk. 19

Recipient Assessment

• Determine recipient HBsAg, anti‑HBs, anti‑HBc, and HBV DNA status.
• Quantify anti‑HBs titers in vaccinated recipients to guide prophylaxis decisions. 17

Prophylaxis Strategies

Post‑Transplant Monitoring

• Check HBsAg and HBV DNA at 6, 12, 24, and 36 months post‑transplant. 16
• Screen for anti‑HBc or anti‑HBs seroconversion during follow‑up. 17

Clinical Pitfalls to Avoid

• Do not automatically reject anti‑HBc‑positive kidney donors; safe use protocols exist. 16
• Avoid routine HBIG administration in kidney recipients, as evidence of benefit is lacking. 17
• Do not select lamivudine as first‑line antiviral prophylaxis when newer agents (entecavir, tenofovir) offer better resistance profiles. 20

Comparative Risk (Kidney vs. Liver)

• The risk of HBV transmission from anti‑HBc‑positive donors is significantly lower in kidney transplantation compared with liver transplantation. 19