Bacterial infection in patients with transfusion-dependent beta-thalassemia in central Taiwan

The microorganisms, outcome of infections and the risk factors were evaluated in 39 patients with beta-thalassemia who received frequent blood transfusions. Among these patients, thirteen developed 22 episodes of infections, and bacteremia accounted for 72.7% (16/22) of all infections. Three patients developed meningitis, two patients had liver abscesses, three patients had soft tissue infections, one patient had a urinary tract infection and one patient had lobar pneumonia. Interestingly, a large proportion of the patients were infected by Gram-negative bacteria. Patients who were implanted with intravascular catheters were most susceptible to bacterial infection (1.70 episodes/patient) (P = 0.0069). So were patients with ferritin levels over 2,000 ng/mL (1.18 episodes/patient) (P = 0.028). The frequency of bacterial infections in patients with splenectomies (1.08 episode/patient) was also significantly higher than that of the average patient (P = 0.025). In conclusion, three major risk factors for bacterial infection were identified in this group of patients: intravascular catheterization, high serum ferritin levels (> or = 2,000 ng/mL) and splenectomy. The infection rate of these patients (0.45 episode/100 patient-year) is about 20-fold higher than that of general pediatric patients (0.023 episode/100 patient-year).