Several different tests are used to diagnose graft-versus-host disease (GvHD) in patients who experience symptoms, as listed below:

Medical history

A clinician will take a detailed medical and family history to note all of a patient's health conditions and previous treatments, as well as the health conditions of their blood relatives.

Physical examination

A physical examination will be performed to observe potential signs of GvHD and may involve:

• Checking body temperature, blood pressure, and breathing rate
• Measuring weight for signs of weight loss
• Listening to the patient's lungs and heart
• Examining the eyes, ears, nose, and throat
• Feeling the patient's organs to determine if they are of normal size, soft or hard, or if there is any pain
• Feeling for enlarged lymph nodes in the neck, underarm, or groin
• Carrying out a full head-to-toe skin exam, including looking at the scalp, face, mouth, hands, feet, torso, extremities, eyes and eyelids, ears, fingers, toes, and toenails for any signs of skin conditions such as rashes, bumps, and dry or peeling skin

Laboratory tests

Several laboratory tests can be used to look for signs of disease and determine if organs are functioning as they are supposed to. Some of the tests used to help accurately diagnose GvHD include:

• A complete blood count to measure the number of red blood cells, white blood cells, and platelets present in the blood
• Liver function tests to measure chemicals that are made or processed by the liver; levels that are too high or too low may indicate that the liver is not functioning correctly
• A lung function test to measure how well the patient is taking in oxygen, how much air is being breathed in and out, and how quickly they are breathing
• A stool sample may be tested for signs of bowel infections, which can cause diarrhea or abdominal pain, also symptoms of GvHD affecting the digestive tract

Biopsies

A biopsy is a procedure where a sample of a patient's tissue or cells is removed and sent for examination by a specialist doctor called a pathologist. The pathologist will look at the cells under a microscope to observe the overall appearance, size, shape, and type of cells. The biopsy required will depend on the area of the body that is affected, for example:

• Skin biopsy
  • If the patient has skin lesions or bumps a sample may be removed and tested
• Liver biopsy
  • A needle through the skin may be used to remove a sample from the liver; this procedure may require a short inpatient stay in hospital
• Gastrointestinal biopsy
  • A sample from the patient's gastrointestinal tract may be taken during an endoscopy (where a device is guided down the throat to examine the food pipe, stomach, and upper parts of the small intestine), colonoscopy, or sigmoidoscopy (both of which involve inserting a device into the rectum to inspect the colon)

Imaging

Imaging tests are painless, non-invasive procedures used to capture pictures of the inside of a patient's body. A radiologist will interpret these images and look for any abnormalities. Some examples of imaging tests used in the diagnosis of GvHD include:

• An X-ray, which uses low-dose radiation to take a picture of the inside of the body
• A computed tomography (CT or CAT) scan, which uses X-ray techniques to create detailed 3D images
• A magnetic resonance imaging (MRI) scan, which uses radio waves and powerful magnets to take pictures of inside the body
• An ultrasound, which uses a probe to send sound waves into the body to produce real-time images and can be used to guide biopsies

References

1. National Comprehensive Cancer Network. Graft-versus-host disease NCCN guidelines for patients. http://www.nccn.org/patients/guidelines/content/PDF/GVDH-patient-guideline.pdf. Accessed Dec 13, 2024.
2. Diagnosing GvHD. Cancer Research UK. https://www.cancerresearchuk.org/about-cancer/coping/physically/gvhd/diagnosing. Accessed Dec 13, 2024.