Transplantation Immunology
Help Questions
USMLE Step 1 › Transplantation Immunology
A 35-year-old man has fever and rising creatinine 2 weeks after kidney transplant while on tacrolimus, mycophenolate, and prednisone; biopsy shows interstitial lymphocytes with tubulitis. Which of the following is the best initial treatment for this patient?
Immediate graft nephrectomy due to hyperacute rejection
High-dose IV glucocorticoids to suppress T-cell activity
Acyclovir therapy for cytomegalovirus-associated nephritis
Low-dose aspirin and statin for chronic vasculopathy
Plasmapheresis plus IVIG to remove donor-specific antibodies
Explanation
This question tests transplantation immunology concepts, focusing on rejection mechanisms and management (USMLE Step 1). Transplantation immunology involves understanding graft rejection types: hyperacute, acute, and chronic, each requiring different management. In this vignette, the patient's symptoms and lab results suggest acute cellular rejection, demonstrated by fever, rising creatinine, and biopsy showing lymphocytes with tubulitis. Choice A is correct because it reflects the appropriate initial treatment with high-dose steroids based on current clinical guidelines. Choice B is incorrect due to it being for antibody-mediated rejection, such as misinterpretation of biopsy as AMR. Teaching strategies include reviewing types of rejection and corresponding management protocols, emphasizing the importance of timely intervention and proper use of immunosuppressive therapy.
A 60-year-old woman has slowly worsening cholestatic labs 5 years after liver transplant; biopsy shows fibrosis and narrowed bile ducts; she takes tacrolimus. Which of the following is the most likely cause of the observed symptoms?
Hyperacute rejection from preformed anti-donor antibodies
Primary nonfunction from ischemia immediately after transplant
Acute GVHD from donor marrow T cells
Chronic rejection with progressive vascular and biliary injury
Acute cellular rejection occurring within the first month
Explanation
This question tests transplantation immunology concepts, focusing on rejection mechanisms and management (USMLE Step 1). Transplantation immunology involves understanding graft rejection types: hyperacute, acute, and chronic, each requiring different management. In this vignette, the patient's symptoms and lab results suggest chronic rejection, demonstrated by slowly worsening cholestatic labs and biopsy showing fibrosis. Choice A is correct because it reflects the vascular and biliary injury of chronic rejection based on current clinical guidelines. Choice C is incorrect due to acute rejection typically occurring early, not at 5 years. Teaching strategies include reviewing types of rejection and corresponding management protocols, emphasizing the importance of timely intervention and proper use of immunosuppressive therapy.
A 40-year-old man develops diffuse maculopapular rash and watery diarrhea 3 weeks after allogeneic bone marrow transplant; bilirubin is elevated and biopsy shows apoptotic bodies; he receives tacrolimus prophylaxis. What is the most likely cause of the observed symptoms?
Cytomegalovirus infection causing isolated colitis without rash
Donor T lymphocytes attacking recipient skin, gut, and liver
Recurrent underlying malignancy infiltrating the gastrointestinal tract
Recipient antibodies binding donor endothelium causing thrombosis
Type I allergy to tacrolimus causing urticaria and bronchospasm
Explanation
This question tests transplantation immunology concepts, focusing on rejection mechanisms and management (USMLE Step 1). Transplantation immunology involves understanding graft rejection types: hyperacute, acute, and chronic, each requiring different management. In this vignette, the patient's symptoms and lab results suggest acute GVHD, demonstrated by rash, diarrhea, elevated bilirubin, and apoptotic bodies post-BMT. Choice A is correct because it reflects the donor T-cell attack in GVHD based on current clinical guidelines. Choice B is incorrect due to describing host antibodies against graft, not GVHD. Teaching strategies include reviewing types of rejection and corresponding management protocols, emphasizing the importance of timely intervention and proper use of immunosuppressive therapy. Distinguishing GVHD from host-versus-graft rejection is key in bone marrow transplant cases.
A 40-year-old man develops rash and diarrhea after allogeneic bone marrow transplant; stool studies are negative and skin biopsy supports GVHD; he is on tacrolimus prophylaxis. Which of the following is the best initial treatment for this patient?
Oral antibiotics targeting Clostridioides difficile as first-line therapy
High-dose IVIG alone as definitive therapy without steroids
High-dose systemic glucocorticoids to suppress donor T-cell response
Immediate discontinuation of all immunosuppression to clear infection
Plasmapheresis to remove recipient anti-donor antibodies
Explanation
This question tests transplantation immunology concepts, focusing on rejection mechanisms and management (USMLE Step 1). Transplantation immunology involves understanding graft rejection types: hyperacute, acute, and chronic, each requiring different management. In this vignette, the patient's symptoms and lab results suggest acute GVHD, demonstrated by rash, diarrhea, and supportive biopsy post-BMT. Choice A is correct because it reflects the initial treatment with high-dose steroids for GVHD based on current clinical guidelines. Choice B is incorrect due to plasmapheresis being for antibody-mediated issues, not GVHD. Teaching strategies include reviewing types of rejection and corresponding management protocols, emphasizing the importance of timely intervention and proper use of immunosuppressive therapy.
A 40-year-old man has rash and profuse diarrhea 3 weeks after allogeneic bone marrow transplant; labs show elevated bilirubin and low albumin; he takes tacrolimus and methotrexate. Which of the following mechanisms is most likely responsible for the patient's condition?
Preformed IgG binding donor ABO antigens causing immediate lysis
Donor CD4+ and CD8+ T cells recognizing recipient HLA antigens
Calcineurin inhibitor nephrotoxicity causing azotemia and oliguria
Immune complex deposition from chronic hepatitis C recurrence
Recipient CD8+ T cells recognizing donor MHC on graft cells
Explanation
This question tests transplantation immunology concepts, focusing on rejection mechanisms and management (USMLE Step 1). Transplantation immunology involves understanding graft rejection types: hyperacute, acute, and chronic, each requiring different management. In this vignette, the patient's symptoms and lab results suggest acute GVHD, demonstrated by rash, diarrhea, elevated bilirubin, and low albumin post-BMT. Choice A is correct because it reflects the donor T-cell mechanism in GVHD based on current clinical guidelines. Choice B is incorrect due to describing host T cells against graft, opposite of GVHD. Teaching strategies include reviewing types of rejection and corresponding management protocols, emphasizing the importance of timely intervention and proper use of immunosuppressive therapy.
A 35-year-old man has fever and graft tenderness 2 weeks after kidney transplant; creatinine is 3.0 mg/dL and Doppler is normal; he takes tacrolimus and mycophenolate. What is the most appropriate next step in management?
Schedule elective nephrectomy due to irreversible rejection
Stop tacrolimus immediately and switch to sirolimus only
Begin broad-spectrum antibiotics for presumed pyelonephritis
Increase oral prednisone and observe for 72 hours
Obtain renal allograft biopsy to confirm rejection type
Explanation
This question tests transplantation immunology concepts, focusing on rejection mechanisms and management (USMLE Step 1). Transplantation immunology involves understanding graft rejection types: hyperacute, acute, and chronic, each requiring different management. In this vignette, the patient's symptoms and lab results suggest acute rejection, demonstrated by fever, graft tenderness, and rising creatinine with normal Doppler. Choice C is correct because it reflects the appropriate next step of biopsy to confirm rejection type based on current clinical guidelines. Choice A is incorrect due to presuming infection without confirmation, such as misinterpretation of symptoms as solely infectious. Teaching strategies include reviewing types of rejection and corresponding management protocols, emphasizing the importance of timely intervention and proper use of immunosuppressive therapy.
A 50-year-old woman is 1 year after heart transplant on tacrolimus and mycophenolate; she is asymptomatic with stable echocardiogram and normal troponin. Which of the following mechanisms is most likely responsible for the patient's condition?
Donor T cells attacking recipient skin and gastrointestinal tract
Suppressed IL-2 transcription leading to reduced T-cell activation
Recipient T cells causing lymphocytic myocarditis from acute rejection
Preformed antibodies causing immediate complement-mediated thrombosis
Progressive graft arteriosclerosis due to chronic rejection
Explanation
This question tests transplantation immunology concepts, focusing on rejection mechanisms and management (USMLE Step 1). Transplantation immunology involves understanding graft rejection types: hyperacute, acute, and chronic, each requiring different management. In this vignette, the patient's symptoms and lab results suggest stable graft function, demonstrated by asymptomatic status and normal tests 1 year post-heart transplant. Choice A is correct because it reflects the mechanism of tacrolimus in preventing rejection based on current clinical guidelines. Choice E is incorrect due to describing recipient T cells in acute rejection, not stability. Teaching strategies include reviewing types of rejection and corresponding management protocols, emphasizing the importance of timely intervention and proper use of immunosuppressive therapy.
A 60-year-old woman has gradual loss of graft function 5 years after liver transplant; she reports fatigue and pruritus; alkaline phosphatase is elevated and biopsy shows fibrosis with bile duct loss despite tacrolimus. Which mechanism is most likely responsible for her condition?
Chronic immune-mediated injury causing progressive fibrosis and scarring
Acute T-cell attack causing prominent portal lymphocytes and edema
Preformed antibodies causing immediate complement-mediated thrombosis
Hepatic artery thrombosis from surgical technical complication alone
Donor lymphocytes attacking recipient skin and intestinal mucosa
Explanation
This question tests transplantation immunology concepts, focusing on rejection mechanisms and management (USMLE Step 1). Transplantation immunology involves understanding graft rejection types: hyperacute, acute, and chronic, each requiring different management. In this vignette, the patient's symptoms and lab results suggest chronic rejection, demonstrated by gradual loss, fatigue, pruritus, elevated alk phos, and biopsy fibrosis. Choice A is correct because it reflects the chronic immune injury mechanism based on current clinical guidelines. Choice B is incorrect due to describing hyperacute rejection, not gradual onset. Teaching strategies include reviewing types of rejection and corresponding management protocols, emphasizing the importance of timely intervention and proper use of immunosuppressive therapy.
A 50-year-old woman is 1 year after heart transplant with stable graft function; she takes tacrolimus and mycophenolate and has normal labs. What is the most appropriate next step in management?
Schedule urgent graft removal due to inevitable chronic rejection
Start plasmapheresis to prevent antibody-mediated rejection prophylactically
Continue current immunosuppression with routine surveillance follow-up
Give high-dose IV steroids despite absence of rejection signs
Stop tacrolimus now to prevent chronic nephrotoxicity in all patients
Explanation
This question tests transplantation immunology concepts, focusing on rejection mechanisms and management (USMLE Step 1). Transplantation immunology involves understanding graft rejection types: hyperacute, acute, and chronic, each requiring different management. In this vignette, the patient's symptoms and lab results suggest stable graft function, demonstrated by normal labs 1 year post-heart transplant. Choice A is correct because it reflects continuing immunosuppression with surveillance based on current clinical guidelines. Choice D is incorrect due to steroids not being indicated without rejection signs. Teaching strategies include reviewing types of rejection and corresponding management protocols, emphasizing the importance of timely intervention and proper use of immunosuppressive therapy.