# Graft-Versus-Host Disease

> Graft-versus-host disease for NEET-PG Medicine, covering acute and chronic GVHD target organs, staging, grading and prophylaxis in transplant recipients.

- Canonical URL: https://prepelephant.com/topics/neet-pg/medicine/graft-versus-host-disease
- Exam / course: NEET-PG · Subject: Medicine
- Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team
- First published: 2026-10-14
- Last updated: 2026-10-14
- Reference basis: Harrison's Principles of Internal Medicine; Hoffbrand's Essential Haematology; Robbins and Cotran Pathologic Basis of Disease
- How to cite: "Graft-Versus-Host Disease", PrepElephant, https://prepelephant.com/topics/neet-pg/medicine/graft-versus-host-disease

## Direct answer

Graft-versus-host disease is an immune reaction in which donor T cells attack the recipient's tissues, most often after allogeneic haematopoietic stem cell transplantation. Acute disease mainly affects the skin, liver and gut, while chronic disease resembles autoimmune disease and can involve the eyes, mouth, skin and lungs.

## What you must remember

- **Mechanism:** Donor T cells recognise recipient tissue as foreign and attack it, so the reaction depends on HLA mismatch and T-cell content of the graft.
- **Timing:** Acute GVHD traditionally appears within the first 100 days after transplant, while chronic GVHD is defined by later onset or by chronic features.
- **Acute target organs:** The skin, liver and gut form the classic target triad, with a maculopapular rash, cholestatic jaundice and watery diarrhoea respectively.
- **Chronic features:** Sclerodermatous skin, lichenoid oral lesions, dry eyes and bronchiolitis obliterans are typical of chronic disease.
- **Graft-versus-leukaemia effect:** The donor immune response against residual leukaemia reduces relapse, which is the benefit that makes allogeneic transplantation worthwhile.
- **Prophylaxis:** A calcineurin inhibitor with a short course of methotrexate is a standard regimen after allogeneic transplantation.
- **Treatment:** High-dose corticosteroids are the first-line therapy for acute GVHD, and ruxolitinib is used for steroid-refractory disease.
- **Transfusion prevention:** Irradiated blood products are given to at-risk recipients to prevent transfusion-associated GVHD.

## Grading acute GVHD by organ stage

A 41-year-old man develops a red, itchy rash and watery diarrhoea 3 weeks after an allogeneic transplant for acute myeloid leukaemia. The first task is to decide whether this is acute GVHD and how severe it is.

1. **Establish the timing:** Acute GVHD traditionally occurs within the first 100 days, so the timeline supports the diagnosis before organ staging begins.
2. **Stage the skin:** Grade the rash by the proportion of body surface involved, moving from a localised rash to erythroderma with bullous change.
3. **Stage the liver:** Use the serum bilirubin, with the classic Glucksberg thresholds lying roughly at 2 to 3, 3.1 to 6, 6.1 to 15 and above 15 mg/dL.
4. **Stage the gut:** Use stool volume and abdominal pain, where severe pain or ileus marks the highest gut stage.
5. **Assign the overall grade:** Combine the organ stages into an overall grade from I to IV, where higher grades carry a worse prognosis.
6. **Confirm histologically:** Biopsy the skin, gut or liver when the diagnosis is uncertain, since infection and drug reactions can mimic GVHD.

## Where the exam tries to catch you

Most traps involve the definition of the reaction, its timing and the lung complication of chronic disease.

- **Trap:** Calling GVHD an infection or a simple immunodeficiency complication. — **Correct:** GVHD is an immune reaction of donor T cells against recipient tissues.
- **Trap:** Viewing GVHD as purely harmful. — **Correct:** The graft-versus-leukaemia effect lowers relapse, so the aim is to control GVHD rather than abolish the donor immune response.
- **Trap:** Confusing bronchiolitis obliterans with a routine chest infection. — **Correct:** It is a serious pulmonary feature of chronic GVHD, and it is managed as part of the chronic disease.
- **Trap:** Using steroids as the main prophylaxis strategy. — **Correct:** Prophylaxis relies on a calcineurin inhibitor with methotrexate or other agents, while steroids are the mainstay of treatment.

## Frequently asked questions

### What is the classic target organ triad in acute graft-versus-host disease?

The skin, liver and gut form the classic target organ triad in acute graft-versus-host disease. Skin involvement appears as a maculopapular rash, liver involvement as cholestatic jaundice, and gut involvement as watery diarrhoea and abdominal pain.

### Which features distinguish chronic graft-versus-host disease from the acute form?

Chronic graft-versus-host disease resembles autoimmune disease, with sclerodermatous skin, lichenoid oral lesions and dry eyes. The lungs can develop bronchiolitis obliterans, which is a serious late complication of the chronic form.

### Which drugs are used for graft-versus-host disease prophylaxis?

A calcineurin inhibitor such as cyclosporine or tacrolimus, combined with a short course of methotrexate, is a standard prophylaxis regimen. Other strategies, such as T-cell depletion or post-transplant cyclophosphamide, are used in selected protocols.

### What is the first-line treatment for acute graft-versus-host disease?

High-dose corticosteroids are the first-line treatment for acute graft-versus-host disease. Ruxolitinib is used for steroid-refractory disease, and the choice of second-line agent follows transplant centre protocols.

### Why are blood products irradiated for transplant recipients?

Irradiation inactivates donor lymphocytes in blood products, which prevents transfusion-associated graft-versus-host disease. It is recommended for immunocompromised patients, including transplant recipients, and for certain related-donor transfusions.