Differential Diagnosis for 72-year-old Male with Symptoms Post-Blood Transfusion

• Single most likely diagnosis:

  • B Febrile reaction: This is the most likely diagnosis given the symptoms of fever (temperature of 39.5°C), tachycardia, and hypotension occurring shortly after a blood transfusion, without evidence of hemolysis. Febrile reactions are common and occur due to the transfusion of blood components that contain white blood cells or their byproducts.

• Other Likely diagnoses:

  • C Allergic reaction: Although less likely than a febrile reaction, an allergic reaction could present with similar symptoms, including tachycardia and hypotension, especially if there's an involvement of anaphylaxis. However, the primary symptom of an allergic reaction would typically include urticaria or rash, which is not mentioned.
  • E Septicaemia: This could be a consideration if the blood product was contaminated, but it's less likely given the immediate onset of symptoms post-transfusion and the lack of specific indicators of infection.

• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.):

  • A Immediate haemolytic reaction: Despite the question stating no evidence of hemolysis on blood film, an immediate hemolytic reaction is a life-threatening condition that must be considered, especially given the acute onset of symptoms post-transfusion. It's crucial to monitor for any signs of hemolysis closely.
  • E Septicaemia: As mentioned, while less likely, septicaemia due to contaminated blood products is a potentially fatal condition that requires immediate attention and should not be missed.

• Rare diagnoses:

  • D Viral hepatitis: This is unlikely to present acutely with the symptoms described (fever, tachycardia, hypotension) immediately after a blood transfusion. Viral hepatitis typically has a longer incubation period and presents with liver function abnormalities and jaundice rather than acute systemic symptoms like hypotension.