A 68-year-old man presents to the emergency department with a 2-day history of fatigue, rash, and abdominal pain. The rash had started on his feet and palms and spread to his trunk, with each lesion being roughly 1cm in size. Past medical history is significant for an allogenic liver transplant 3 weeks prior, hyperlipidemia, and obesity. Medications include tacrolimus, mycophenolate and prednisone which have all been taken consistently at appropriate doses. He consistently drank about 30 beers every week for the past 45 years, quitting 2 years ago He does not have a smoking or recreational drug history. Vital signs are temperature 37.1° C (98.6° F), blood pressure 116/78 mmHg, pulse 106 beats/min, respirations 19/min, and 97% oxygen saturation. On physical examination, he has a maculopapular rash on his chest and arms, as well as diffuse abdominal tenderness with guarding. CBC shows decreased levels of platelets, erythrocytes, and leukocytes. AST, ALT, and GGT, are within normal limits. Flow cytometry shows low levels of CD3+ and CD19+ cells. Abdominal ultrasound does not show obvious abnormalities.
Which of the following is the most likely mechanism for the patient’s symptoms?
- A) Hemolysis of red blood cells
- B) Infection due to immune suppression
- C) Serositis due to systemic lupus erythematosus (SLE)
- D) Type II hypersensitivity reaction
- E) Type IV hypersensitivity reaction
E) Type IV hypersensitivity reaction
This patient is exhibiting graft vs host disease, a type IV hypersensitivity reaction occurring after hematopoietic stem cell or liver transplant. This reaction is due to donor T cells attacking host tissues. Since the T cells are from the donor liver, liver function tests are unaffected.
Answer choice A: Hemolysis of red blood cells, is incorrect. While hemolytic anemia may occur after transplantation, it would primarily cause symptoms of anemia, decreased hemoglobin and hematocrit, and elevated bilirubin levels rather than a rash and abdominal pain.
Answer choice B: Infection due to immune suppression, is incorrect. This patient is immune suppressed because of the medications he is taking, but does not have signs of infection such as localizing symptoms, fever, elevated white blood cell count, or abnormal findnings on ultrasonography.
Answer choice C: Serositis due to systemic lupus erythematosus (SLE), is incorrect. SLE can cause a rash, particularly a butterfly rash on the face, but this typically does not present on the chest or hands. This patient does not have findings consistent with serositis or lab results that support a diagnosis of SLE.
Answer choice D: Type II hypersensitivity reaction. A type II hypersensitivity reaction would lead to acute transplant rejection of the donor graft. In this case the liver is unaffected.
Key Learning Point
Graft vs. host disease, a type IV hypersensitivity reaction, can occur after transplant, classically of the liver or hematopoietic stem cells due to the presence of donor T cells in the transplanted tissues. These T cells do not attack the transplanted organ.
