Diagnosis: Febrile Non-Hemolytic Transfusion Reaction (FNHTR)
The patient most likely has a febrile non-hemolytic transfusion reaction (FNHTR), which is the most common transfusion reaction, occurring in 1.1-2.15% of transfusions and typically presenting with isolated fever and mild symptoms during or shortly after transfusion. 1
Clinical Reasoning
Timing and Presentation Analysis
The key diagnostic features in this case are:
- Fever and shortness of breath developing 2 hours after transfusion initiation - This timing is critical for differential diagnosis 2
- Hemoglobin of 70 g/L - Indicates severe anemia but stable enough that the patient survived to develop symptoms 1
- Absence of hypotension or hemodynamic instability - This is crucial in ruling out more serious reactions 3
Why FNHTR is Most Likely
FNHTR presents with fever occurring within 1-6 hours of transfusion, often accompanied by mild dyspnea, and represents a benign, self-limited reaction. 1, 2 The fever rate with prestorage leukoreduction is 1.1%, and 2.15% with poststorage leukoreduction 1. This patient's presentation at 2 hours post-transfusion with fever and dyspnea, without mention of severe hypoxemia, hypotension, or pulmonary edema, fits this diagnosis perfectly.
Excluding Other Diagnoses
TRALI (Option D) is excluded because:
- TRALI presents with severe hypoxemia, bilateral pulmonary infiltrates, and acute respiratory distress within 1-2 hours, not just "shortness of breath" 3, 4
- TRALI requires non-cardiogenic pulmonary edema and represents a life-threatening emergency with fluid in the endotracheal tube 3
- The question describes dyspnea but does not mention severe hypoxemia, bilateral infiltrates, or respiratory failure that characterizes TRALI 5, 6
Allergic reaction (Option A) is excluded because:
- Allergic reactions typically present with urticaria, pruritus, and skin manifestations, not primarily fever and dyspnea 3
Anaphylactic reaction (Option B) is excluded because:
- Anaphylaxis presents with severe hypotension, bronchospasm, angioedema, and cardiovascular collapse within minutes 3
- The patient's presentation lacks these life-threatening features
Critical Clinical Distinctions
Fever occurring during or immediately after transfusion (within minutes to 2 hours) with hypotension or hemodynamic instability suggests serious reactions requiring immediate intervention, such as acute hemolytic reaction or bacterial contamination. 2 This patient lacks these features.
TACO can develop during transfusion or up to 12 hours afterward, presenting with respiratory distress, pulmonary edema, cardiovascular changes, and potentially fever. 3 However, TACO is now the most common cause of transfusion-related mortality and would present with clear signs of fluid overload, which are not described here 3.
Management Implications
For FNHTR, the appropriate management includes:
- Stop the transfusion immediately and maintain IV access 3
- Administer antipyretics (this is appropriate for FNHTR but contraindicated in more serious reactions until they are excluded) 3
- Monitor vital signs closely 3
- Rule out more serious reactions before attributing symptoms to FNHTR 2
Key Clinical Pitfall
Do not dismiss fever as "just FNHTR" without excluding life-threatening causes, particularly bacterial contamination and acute hemolytic reactions. 2 However, given the clinical presentation described—fever and dyspnea at 2 hours without hemodynamic instability, severe hypoxemia, or pulmonary edema—FNHTR remains the most likely diagnosis among the options provided.