Following allogeneic hematopoietic stem cell transplant (allo-HCT), which uses healthy stem cells from a donor, many doctors prescribe antibiotics to patients as a protective measure. Many individuals become neutropenic during this process. This means that they have low levels of neutrophils, a type of white blood cell that plays a role in fighting infection. Since they have a higher risk of potentially dangerous or severe infections, antibiotics are seen as a way to stave those off. However, shares an article in MedPage Today, the use of certain antibiotics increases the risk of developing graft-versus-host disease (GvHD). 

Identifying the Implications of Antibiotic Use

Within a study published in JAMA Network Open, a research team explored the relationship between antibiotic exposure and GvHD. It included data from 2,023 adults who underwent T-replete allo-HCT over an 11-year period. A slight majority were male. The researchers analyzed 17 separate classes of antibiotics. They found that:

• Using carbapenems—broad-spectrum antibiotics including Meropenem, Imipenem, Doripenem, and Ertapenem—saw a heightened risk of acute GvHD within two weeks of stem cell transplantation. Penicillin with a β-lactamase inhibitor also increased the risk within the first week. The researchers suggest that doctors should not prescribe carbapenems or penicillin with a β-lactamase inhibitor in the early stages following allo-HCT. 
• Alternately, using penicillin with a β lactamase inhibitor within a week before allo-HCT reduced the risk of GvHD. 
• Fluoroquinolones, 3rd generation (or later) cephalosporins, penicillins, aztreonam, and trimethoprim sulfamethoxazole also increased GvHD risk at certain points. 
• After 6 months, 72% (approximately 1,457 people) had developed acute GvHD. 15% of these individuals had grade III or IV GvHD. 206 patients with grade II GvHD died due to complications, as well as 102 patients with grade III or IV GvHD.

The researchers question whether damage to the microbiota could contribute to this, but more research and evaluation is needed. For now, the researchers hope that these findings can help shape treatment and care programs to better meet patient needs and uplift patient health. 

Understanding Graft-versus-Host Disease (GvHD)

Graft-versus-Host disease is a complication that can occur after allogeneic stem cell or bone marrow transplants. In this condition, the transplanted cells view your body as foreign or threatening. The transplanted cells attack the recipient’s body, leading to potentially life-threatening issues. GvHD can be acute (happening within the first six months after transplant) or chronic (which can last a lifetime). 

Your risk of GvHD is higher if you receive stem cells from a related HLA-mismatched donor, an unrelated HLA-matched donor, or a donor who was previously pregnant. Having donor cells taken from the bloodstream or being older in age (or getting donor cells from an older individual) also increase the risk. 

Symptoms may differ between acute and chronic GvHD. Signs of acute GvHD may include:

• Nausea and vomiting
• Diarrhea
• Abdominal pain
• Jaundice (yellowing of the skin, eyes, and mucous membranes)
• Problems with liver function
• Skin itchiness or redness

In comparison, people with chronic GvHD may experience:

• Dry eyes and/or mouth
• Unintended weight loss
• Shortness of breath
• Fatigue
• Rashes
• Joint and muscle pain and stiffness