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Overview
Comprehensive evaluation is thorough: multiple visits, blood work done over weeks, imaging tests, and maybe a talk with a mental health counselor. It seems like a lot of testing, but each test has a reason. Your team is making sure you're truly healthy enough to donate.
Evaluation takes four to eight weeks total. Some tests are done more than once because trends matter more than single results. By the end, you'll know exactly what to expect on collection day. Your team will have confirmed you're safe to go forward.
What the evaluation process involves
The full donor evaluation
Evaluation overview. Comprehensive evaluation typically involves:
- Evaluation timeline: 4-8 weeks from match confirmation
- Multiple phone appointments with your coordinator
- In-person appointments with the center's physician
- Lab tests (blood work, coagulation studies, infection screening)
- Imaging studies to assess organ function
- Mental health counseling to explore emotional readiness
The evaluation process builds systematically. Initial labs confirm baseline health. Follow-up labs closer to collection update your status. Imaging assesses organ function. By collection day, nothing should surprise you.
Why evaluation matters. This process serves multiple purposes:
- Confirms you're healthy enough to donate safely
- Identifies any conditions requiring special precautions
- Establishes baseline health status for post-donation comparison
- Ensures you fully understand the procedures and risks
- Documents informed consent before collection
For some donors, evaluation overlaps with filgrastim injections or immediate pre-collection preparation, shortening the overall timeline somewhat.
Medical testing
Medical testing during evaluation is comprehensive. Some tests confirm initial screening findings; others provide new information. You might wonder why you're being tested multiple times—repetition ensures results are accurate and helps track any changes in your status.
Blood work
Complete blood work is repeated closer to collection to ensure your counts remain adequate. Additional tests might include cardiac enzymes, coagulation studies (how well your blood clots), and additional infectious disease testing if exposure occurred since your initial screen. Some donors receive testing for Cytomegalovirus (CMV) status, which can affect transplant outcome.
Bone marrow donors often need additional testing to ensure they can safely undergo anesthesia. This might include liver function studies (assessing your body's ability to metabolize anesthetic drugs) and continued infectious disease monitoring.
Infectious disease screening
Comprehensive infectious disease testing checks for infections that could be transmitted to the immunocompromised recipient. In addition to HIV, hepatitis B and C, and syphilis, donors are tested for CMV, Epstein-Barr virus (EBV), and possibly others based on risk factors.
Some donors undergo tuberculosis screening, especially if they have risk factors or travel history. Donors are asked about potential exposures since initial screening. If you've had a possible exposure, you might need retesting or a delay before collection.
Physical examination
Your evaluation includes detailed physical exams beyond initial screening. For PBSC donors, your spleen is assessed because filgrastim can cause splenic enlargement and, rarely, rupture. Ultrasound typically measures your spleen size. If enlargement is found, you might have restrictions on strenuous activity during mobilization.
For bone marrow donors, cardiac evaluation is more thorough. You might have an EKG, echocardiogram (ultrasound of the heart), or stress test depending on your age, medical history, and risk factors. This ensures anesthesia is safe.
Choosing your collection method
During evaluation, you'll discuss which collection method (PBSC or bone marrow) is planned. Sometimes the patient's transplant center recommends one; sometimes you have choice. Your medical team discusses pros and cons specific to your health.
If you have significant blood vessel issues, PBSC collection (which requires good vein access for the catheter) might be difficult, and bone marrow might be preferred. If you have low platelet counts or bleeding concerns, bone marrow's surgical approach might be safer. If you have significant heart disease, PBSC might be preferred to avoid anesthesia risks.
Occasionally donors have strong preferences. You might fear surgery and strongly prefer PBSC. Or you might worry about filgrastim side effects and prefer bone marrow. While the patient's needs come first, your strong preference is respected when medically feasible.
- Patient's transplant center usually recommends method
- Your medical history affects suitability
- Vein access matters for PBSC
- Heart health affects anesthesia safety
- Your strong preferences are considered
Timeline from match to donation
The typical timeline is faster than you might expect. Match confirmation to initial screening: 1-2 weeks. Initial screening to comprehensive evaluation: 2-4 weeks. Comprehensive evaluation to collection: 2-4 weeks. Total: 5-10 weeks from match to donation for unrelated donors.
Family donors often move faster. Related match to evaluation: 1-2 weeks. Evaluation to collection: 2-3 weeks. Family timelines can be compressed to 4-6 weeks from match to collection if the patient's condition is urgent.
This timeline assumes everything proceeds smoothly. If testing reveals an issue requiring treatment or clarification, timelines extend. An infection might require 2 weeks of treatment before retesting. Additional cardiac evaluation might add 2-3 weeks. These delays are normal and necessary for safety.
- Unrelated donor timeline: 5-10 weeks match to collection
- Family donor timeline: 4-6 weeks (often faster)
- Delays occur for testing clarification or treatment
- Urgent cases move through faster
- Patient condition affects urgency
Questions to ask your team
As you progress through evaluation, you might have questions about your specific situation. Don't hesitate to ask. Your coordination center and medical team expect questions and welcome them. If something isn't clear, ask again.
About your match and procedure. Ask about:
- What are my exact HLA match details with this patient?
- What does my specific test result mean?
- If bone marrow is planned, how much marrow will be collected?
- If PBSC is planned, how many collections might be needed?
- What's the recovery timeline for my specific situation?
- What should I do if I develop symptoms before collection?
- Can my support person stay with me during collection?
About the recipient. Ask about:
- What information will I learn about the recipient?
- Will I be able to contact them later if both agree?
Some donors write down their questions so they don't forget during appointments. Some bring their support person to help explain what's being discussed. Some ask for written summaries of their results and plans. These practices help reduce anxiety and ensure full understanding.
Helpful tips. When asking questions:
- Ask the same question multiple times if needed for clarity
- Write down questions ahead of appointments
- Bring your support person to appointments
- Request written summaries of results and plans
Additional Detailed Information
Additional Information
Detailed medical testing protocols
Repeat blood work rationale. Multiple blood draws across weeks show trends rather than isolated values. Hemoglobin or platelet counts that trend downward might indicate underlying disease. Serial testing also ensures donors haven't become anemic from multiple lab draws—phlebotomists may be instructed to limit draw volumes for frequent donors.
Coagulation studies. Tests like PT/INR and aPTT assess how quickly blood clots. Abnormalities might indicate bleeding disorders or vitamin K deficiency. Donors with bleeding disorders might require additional evaluation but can often still donate with special precautions.
CMV status determination
Cytomegalovirus serology. Tests for IgG and IgM antibodies to CMV. CMV-seropositive donors can transmit virus to CMV-seronegative recipients, causing post-transplant CMV disease. CMV-seronegative donors are preferred for CMV-seronegative recipients. However, matching on CMV status is a lesser priority than HLA matching.
Cardiac evaluation depth
EKG interpretation. Assessment for left ventricular hypertrophy, ischemia, arrhythmia, or conduction abnormalities. ST-segment changes, T-wave inversions, or severe arrhythmias require cardiology evaluation before anesthesia clearance.
Echocardiogram. Ultrasound assessment of heart structure and function, measuring ejection fraction (how effectively the heart pumps), valve function, and wall motion. Ejection fraction >50% is generally reassuring; significantly reduced ejection fraction requires cardiology review.
Stress testing. For donors with multiple cardiac risk factors or borderline test results, stress testing (exercise EKG or chemical stress test) reveals exercise-induced ischemia and guides anesthesia risk assessment.
Spleen assessment for PBSC donors
Baseline spleen ultrasound. Measures spleen length and area. Normal spleen is typically <13 cm in length. This baseline allows comparison if pre-collection ultrasound shows enlargement. Significant splenic enlargement (>15 cm) increases rupture risk and might be a contraindication to PBSC donation.
Written By:
Transplants.org Staff
Last Reviewed: February 26, 2026
Informed By:
Transplants.org, with participation from 23 leading U.S. transplant centers, led the largest comparative analysis of patient educational materials in transplant history. We recognize the participating centers who helped inform and inspire our direction with initial patient-centered educational content:
- Mayo Clinic (Co-Author)
- Vanderbilt University Medical Center (Co-Author)
- Johns Hopkins Hospital (Co-Author)
- UCLA Medical Center (Co-Author)
- UCSF Medical Center (Co-Author)
Transplants.org is an independent nonprofit organization and participation is not an endorsement by these organizations.
