1078. Higher-risk Myelodysplastic Syndromes are Associated with an Increased Risk of Infection
Session: Poster Abstract Session: Infection in Immunocompromised Patients
Saturday, October 22, 2011
Room: Poster Hall B1
Background: The descriptive epidemiology of infections in the myelodysplastic syndromes (MDS) was last described in the early 1990s.  Since then, the number of MDS diagnoses has increased as the pathologic classification has changed and new therapeutic agents have been approved by the Food and Drug Administration. This evolution in disease understanding may alter the risk and types of infections.

Methods:  We retrospectively reviewed the medical records of all adult patients with MDS seen in the Cleveland Clinic (CC) MDS Clinic from 2000-2010. All diagnoses were confirmed at CC and classified by World Health Organization criteria, with “higher-risk” MDS defined as subtypes with >5% myeloblasts. Inpatient admissions to the CC Health System were examined for infectious complications. Patients with an initial MDS stage of acute myeloid leukemia or a history of bone marrow transplant prior to their MDS diagnosis were excluded.

Results:  Out of 497 patients evaluated, 201 distinct episodes of infection or neutropenic fever were found in 104 patients (21%); 46 patients (9%) had >1 episode of infection.  The overall probability of acquiring an infection at one year was 0.15 (95% CI 0.12-0.18). Probability of infection was highest in higher-risk MDS (refractory anemia with excess blasts-2) and lowest in lower-risk MDS (refractory cytopenia with unilineage dysplasia or 5q-) (P = 0.0013). Pneumonia was the most common infection, followed by neutropenic fever.  Most bloodstream infections were intravenous (IV) catheter-associated.  Bacteria were the predominant pathogens, with Staphylococcus aureus being the most common organism isolated from any source. Overall, gram positive organisms were slightly more predominant than gram negative organisms.  Invasive fungal infections were uncommon, occurring mainly in the setting of higher-risk MDS with neutropenia or in association with long-term IV catheters.  Viral pathogens were infrequently recovered, with influenza A being the most common.

Conclusion: Patients with higher-risk MDS, especially refractory anemia with excess blasts-2, are at an increased risk for infectious complications, particularly pneumonia. Patients with lower-risk MDS do not appear to be at an increased risk of infectious complications.


Subject Category: J. Clinical practice issues

Liam Sullivan, DO1, Mikkael Sekeres, MD2, Nabin K. Shrestha, MD, MPH1, Robert Butler, MS3 and Sherif Mossad, MD4, (1)Infectious Disease, Cleveland Clinic, Cleveland, OH, (2)Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, (3)Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH, (4)Infectious Diseases, Medicine Institute and Transplant Center, Cleveland Clinic Foundation and Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH

Disclosures:

L. Sullivan, None

M. Sekeres, None

N. K. Shrestha, None

R. Butler, None

S. Mossad, roche: Investigator, Research support
GSK: Investigator, Research support
Chimerix: Investigator, Research support

Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.