IV iron treatment improves survival, increases hemoglobin levels in anemic patients with acute bacterial infection | ASH 2025

Intravenous iron treatments improve survival and increase hemoglobin levels for anemic patients hospitalized with acute bacterial infections, according to an abstract presented this morning at the 67th American Society of Hematology (ASH) Annual Meeting and Exposition by Haris Sohail, M.D., a fellow in hematology-oncology at the Charleston Area Medical Center Institute for Academic Medicine. The research dispels a decades long belief that iron infusions feed bacteria, leading to worse outcomes for sick patients.

Anemia is a blood condition in which the body does not make enough red blood cells, which contain hemoglobin, the iron-rich protein that is responsible for carrying oxygen to the body’s tissues. Iron deficiency anemia is the most common form of anemia, impacting several million people worldwide. It is caused by not eating enough iron-rich foods or from blood loss during menstruation, pregnancy or digestive disorders. Symptoms include dizziness, fatigue and pale skin. Anemia remedies include an intake of iron rich foods such as meat, beans and spinach or iron supplements. Iron infusions are effective because they bypass the digestive system, quickly restoring red blood cell count.

Acute bacterial infections are common in patients with iron deficient anemia because the body’s lack of hemoglobin makes it hard to fight off infections. However, iron is a prooxidant and an important nutrient for bacterial growth. Conflicting past evidence showing that it may worsen infections means many physicians avoid giving anemic patients IV treatments who are already sick.

“Due to this belief, a lot of patients have been left untreated, probably at a time when the body needed IV iron the most, and until now, there have been no large-scale studies done that support or refute this data,” Sohail said during his presentation.

Sohail and his team analyzed the outcomes of more than 85,000 anemic patients hospitalized with at least one of 6 infections, including MRSA bacteremia, pneumonia and bacterial meningitis, between the years 2000-2024. The team found that not only were IV iron treatments not associated with any harm, but they also led to lower long-term and short-term mortality and better hemoglobin recovery in every instance except for in meningitis patients, who showed no statistically significant survival outcomes or hemoglobin increases. The greatest mortality decreases were seen in the MRSA bacteremia and pneumonia cohorts.

“[The clinical implications] are massive, not just for the field of hematology, but also for infectious disease, hospital medicine and even critical care medicine,” Sohail said. “We'll see a lot of patients with acute infections and iron deficiency, as it appears that IV iron is safe during infections and correcting anemia may support the immune system and also help with the long-term recovery.”

Sohail also said that further studies are needed to validate this recent data and to understand how IV iron treatments strengthen the immune systems of anemic patients. 

Sohail will present the full abstract, titled ‘Deciphering the dilemma: Intravenous (IV) iron use in iron deficiency anemia during acute infections,’ on December 7.

ASH 2025 is being held in Orlando from December 6 – 9.