Suspected Acute Haemolytic Transfusion Reaction With an Identity Mismatch
A 64-year-old man with a haemoglobin of 6.9 g/dL is prescribed two units of red cells for symptomatic anaemia. The first unit is started at 14:10. After about 20 mL over 15 minutes he develops rigors, a temperature of 39.2 °C, flank pain, and hypotension (84/50 mmHg). His urine is dark red. The nurse calls the blood bank. The compatibility label on the unit reads hospital number 884231, but the patient’s wristband reads 884213; both the unit label and wristband carry the name “Ahmed Al-Sayed”. The patient is group O RhD-positive and the unit is labelled group O RhD-positive. A post-transfusion EDTA sample has a positive direct antiglobulin test with anti-IgG and anti-C3d; the post-transfusion plasma is pink, and urine haemoglobin is 4+. The clerical check has not been completed. The blood bank has no spare segments from the unit and the bag has been returned.
1. List the immediate clinical and laboratory actions, including which samples must be collected and how the returned unit should be handled.
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The transfusion must be stopped immediately. The intravenous line should be maintained with normal saline using new tubing, and the patient should be assessed and treated for hypotension and shock. The physician and blood bank must be notified at once. The bag and giving set should be returned to the blood bank without being discarded, clamped, labelled with the patient details and time, and kept at the correct temperature. A post-transfusion EDTA sample is needed for a direct antiglobulin test and repeat ABO/Rh grouping; a clotted sample is needed for repeat antibody screen and crossmatch. A first-voided urine sample should be collected for haemoglobin, and blood should be sent for repeat full blood count, LDH, haptoglobin, bilirubin, renal function, and coagulation. The clerical check must be completed immediately: the unit label, compatibility label, patient wristband, and request form must be compared. Because there are no spare segments, the returned bag and any remaining tubing contents become the only unit material available for repeat grouping and investigation, so they must not be discarded or washed. The blood bank should also retrieve the original pre-transfusion sample and all records for review.
2. Interpret the serological and urine findings. What is the most likely cause, and how does the clerical discrepancy alter your investigation?
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A positive direct antiglobulin test with both anti-IgG and anti-C3d, pink plasma, and haemoglobinuria indicate immune-mediated intravascular haemolysis. The most feared cause is ABO incompatibility, but both the patient and the unit are labelled group O RhD-positive, so either the labels are wrong or the pre-transfusion sample was drawn from the wrong patient. The hospital-number mismatch is a red flag for a wrong-blood-in-tube error or a wrong-unit error. The investigation must therefore repeat ABO/Rh grouping on the post-transfusion sample and on the returned bag, repeat the antibody screen and crossmatch, and compare all records. If the unit is actually group A or B, an ABO-incompatible transfusion becomes the leading explanation. If the unit proves to be group O, another complement-fixing antibody or a labelling error still needs exclusion. The original pre-transfusion sample must be retested and its identity verified; if it belonged to another patient, the crossmatch result is invalid. The laboratory should not assume a febrile non-haemolytic reaction or a mild allergic reaction. The combination of shock, haemoglobinuria, and a positive direct antiglobulin test requires full hemolytic transfusion reaction work-up.
3. What reporting, look-back, and preventive actions should follow?
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The blood bank physician and the hospital transfusion committee or haemovigilance programme must be informed. A transfusion reaction report should be completed, including the time of onset, volume transfused, clinical signs, laboratory results, clerical findings, and outcome. The event should be reported to the Kuwait Ministry of Health through the required hemovigilance or patient-safety route. Other components from the same donation should be quarantined and not issued until the donor and unit are cleared. If a unit was mislabelled or a sample was misidentified, all patients who received components from the implicated donation or who were crossmatched using the same sample must be reviewed. A root-cause analysis should examine sample collection, bedside identity checks, two-person verification, barcode scanning, and the handling of patients with similar names. Corrective actions may include re-education, a second independent identity check at the bedside, and an electronic identification system. The final report should distinguish laboratory error, clerical error, and a true donor-related event, and should state what changes were made.