An article in the journal Hematology, part of an educational program by the American Society of Hematology, points out that the risk for sepsis lasts a lifetime, with infections occurring as late as 40 years after splenectomy. The spleen plays a major role in preventing infections, including the ability to trigger innate and adaptive immune responses to pathogens, including encapsulated bacteria, according to the report.
Grace M. Lee, MD, of Stanford University School of Medicine notes that infectious complications due to encapsulated organisms such as Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae can lead to fulminant sepsis and death, both in the period shortly after splenectomy and also in immunocompromised patients. Patients with asplenia are also at risk for less common infections due to Capnocytophaga, Babesia, and malaria, the report adds.
“Antibiotic prophylaxis, vaccines, and patient and family education are the mainstays of prevention in these at-risk patients. Recommendations for antibiotic prophylaxis typically target high-risk periods, such as 1 to 3 years after splenectomy, children ≤5 years of age, or patients with concomitant immunocompromise,” Dr. Lee writes. “However, the risk for sepsis is lifelong, with infections occurring as late as 40 years after splenectomy.”
Currently available vaccines recommended for patients with asplenia include pneumococcal vaccines—the 13-valent pneumococcal conjugate vaccine followed by the 23-valent pneumococcal polysaccharide vaccine—as well as the meningococcal vaccines (meningococcal conjugate vaccines for serogroups A, C, Y, and W-135 and serogroup B meningococcal vaccines), H influenzae type b vaccines, and inactivated influenza vaccines.
Also recommended are ongoing booster doses for pneumococcal and meningococcal vaccines to maintain protection.
“Despite the availability of prevention tools, adherence is often a challenge,” according to the article. “Dedicated teams or clinics focused on patient education and monitoring have demonstrated substantial improvements in vaccine coverage rates for individuals with asplenia and reduced risk of infection. Future efforts to monitor the quality of care in patients with asplenia may be important to bridge the know-do gap in this high-risk population.”
Background information in the article notes that asplenia or hyposplenia occurs with a loss of spleen function, either because of anatomic or functional effect. Surgical removal is the common cause of anatomic asplenia, either because of trauma or for therapeutic reasons (e.g., immune thrombocytopenic purpura [ITP], autoimmune hemolytic anemia, hereditary spherocytosis) or autoinfarction in sickle cell disease. Dr. Lee suggests that rarely is due to congenital asplenia syndromes, such as isolated congenital asplenia or heterotaxy syndromes.
In the case of functional asplenia or hyposplenism, hematological diseases such as sickle cell disease or hemoglobinopathies, oncologic conditions such as chronic graft-versus-host disease after allogeneic hematopoietic and stem cell transplant, and immunological reasons such as antiphospholipid syndrome, severe celiac disease, or autoimmune diseases can be the cause, according to the report.
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