Mathematical modeling may help to predict specific bird-pathogen interactions and to identify key parameters that need to be better estimated through additional research. Long-term records enable establishment of databases, which would illustrate bird-pathogen relationships in natural conditions. These data would focus on hosts, their migration, population age, behavior, and so forth. Host-pathogen interactions should be described by using data such as antibody prevalence in different age classes, frequency of virus isolation, and characterization of the strains involved. Complementary laboratory and field experiments within a controlled environment might also provide relevant information. All these investigations should gradually make it possible to gather valuable baseline data to test specific hypotheses and gain new insights in bird-pathogen relationships in Mediterranean wetlands. Prolonged extracorporeal membrane oxygenation therapy for severe acute respiratory distress syndrome in a child affected by rituximab-resistant autoimmune hemolytic anemia: a case report INTRODUCTION: Autoimmune hemolytic anemia in children younger than 2 years of age is usually characterized by a severe course, with a mortality rate of approximately 10%. The prolonged immunosuppression following specific treatment may be associated with a high risk of developing severe infections. Recently, the use of monoclonal antibodies (rituximab) has allowed sustained remissions to be obtained in the majority of pediatric patients with refractory autoimmune hemolytic anemia. CASE PRESENTATION: We describe the case of an 8-month-old Caucasian girl affected by a severe form of autoimmune hemolytic anemia, which required continuous steroid treatment for 16 months. Thereafter, she received 4 weekly doses of rituximab (375 mg/m(2)/dose) associated with steroid therapy, which was then tapered over the subsequent 2 weeks. One month after the last dose of rrituximab, she presented with recurrence of severe hemolysis and received two more doses of rrituximab. The patient remained in clinical remission for 7 months, before presenting with a further relapse. An alternative heavy immunosuppressive therapy was administered combining cyclophosphamide 10 mg/kg/day for 10 days with methylprednisolone 40 mg/kg/day for 5 days, which was then tapered down over 3 weeks. While still on steroid therapy, the patient developed an interstitial pneumonia with Acute Respiratory Distress Syndrome, which required immediate admission to the intensive care unit where extracorporeal membrane oxygenation therapy was administered continuously for 37 days. At 16-month follow-up, the patient is alive and in good clinical condition, with no organ dysfunction, free from any immunosuppressive treatment and with a normal Hb level. CONCLUSIONS: This case shows that aggressive combined immunosuppressive therapy may lead to a sustained complete remission in children with refractory autoimmune hemolytic anemia. However, the severe life-threatening complication presented by our patient indicates that strict clinical monitoring must be vigilantly performed, that antimicrobial prophylaxis should always be considered and that experienced medical and nursing staff must be available, to deliver highly specialized supportive salvage therapies, if necessary, during intensive care monitoring. Autoimmune hemolytic anemia (AIHA) in children is usually characterized by a severe course with a mortality rate of approximately 10% [1] . The required prolonged immunosuppressive therapy often leads to steroid dependence [2] . The administration of non-steroidal immunosuppressive drugs such as cyclosporine A, cyclophosphamide and azathioprine, has been used in the past [1] [2] [3] [4] . Nowadays, the use of monoclonal antibodies such as rituximab, has given promising results for pediatric refractory AIHA [5] [6] [7] , with sustained remissions in the majority of patients. Nevertheless, potentially life-threatening infections are known to occur with rituximab [7] . In the event of rituximab failure, there is no general consensus or guidelines available indicating precisely how to manage resistant forms of AIHA. Heavy immunosuppression consisting of the combined use of cyclophosphamide and high-dose steroids may be considered [8, 9] .