Children with acute lymphoblastic leukemia (ALL) who relapse after successful frontline induction and consolidation therapy can achieve long-term event-free survival with aggressive polychemotherapy. A second remission is achieved by more intensive short-course elements containing high-dose methotrexate and high-dose cytarabine . For treatment or prevention of CNS leukemia, intrathecal therapy is given during intensive treatment, and CNS irradiation is administered after the end of intensive chemotherapy . In testicular relapse, local irradiation or orchidectomy is performed . Bone marrow suppression and pancytopenia is a known complication of both ALL itself and cancer chemotherapy. Neutropenia increases patients' susceptibility to opportunistic infections. To overcome neutropenia, subcutaneous injection of Granulocyte colony-stimulating factor (G-CSF) is used to enhance the production of neutrophils within the bone marrow .
Blood transfusion is frequently needed for anemia and thrombocytopenia. Urgent platelet transfusion is required in this patient because of severe thrombocytopenia and DIVC.
Irradiated apheresis platelets were used. Irradiation removes leukocytes from the platelet. The major advantage of apheresis platelets is that enough platelets can be collected from a single donor to constitute a transfusion dose. The reduction in donor exposures by using apheresis platelets and the removal of leukocytes have the advantages of reducing transfusion-transmitted infections and the incidence of platelet alloimmunization.
The bacterial risk associated with platelet transfusions is high because platelets are stored at 22°C rather than at 4°C as are red cells . However, the risk of contamination of any blood product with fungal element is very low. The development of fungal septicaemia within 48 hours of platelet transfusion in this patient could simply due to superinfection in a case of immunosuppression from ALL and immunosuppressive therapy. Alternatively platelet transfusion may lead to TRIM which increases the risk of endogenous fungal endophthalmitis above and beyond that posed by leukemia.
TRIM occur as a result of allogeneic blood transfusions (ABT) which induce clinically significant immunosuppression in recipients. Blood component transfusion causes recipient immunomodulation, with stimulation of certain immune responses and suppression of others, resulting in an impaired immune competence. TRIM has been linked to an improved clinical outcome in the setting of renal allograft transplantation. Possible deleterious TRIM-associated effects include an increased rate of cancer recurrence and of post-operative bacterial infection. TRIM is attributed to immunomodulatory and pro-inflammatory mechanisms. TRIM effects may be mediated by allogeneic mononuclear cells, white-blood-cell (WBC)-derived soluble mediators and soluble HLA peptides circulating in allogeneic plasma .
The presence of platelet-derived bioactive substances such as plasminogen activator inhibitor-1, tissue inhibitor of metalloproteinases-1, vascular endothelial growth factor and tissue factor, in platelet concentrates, may play an important role in TRIM . It is now known that platelets possess cell membrane, cytoplasmic, and secrete CD40 ligand (CD40L). Previously thought to be involved only in hemostasis, platelets also function in innate and adaptive immunity and possess proinflammatory, as well as pro-thrombotic properties. They interact with other platelets, endothelial cells, lymphocytes, dendritic cells, and fibroblasts. Soluble forms of CD40L (sCD40L) in the human circulation are almost entirely derived from platelets. Elevated levels of CD40L are associated with vascular disease, abnormal clotting (thrombosis), lung injury, and autoimmune disease .
All antifungals are fungistatic, therefore neutrophilic recovery is important for the eradication of any disseminated fusariosis . Early and aggressive local and systemic antifungal therapy is crucial, although the visual prognosis is generally poor. Binder et al identified visual acuity at diagnosis and the presence of hypopyon as factors associated with outcome . In their series, all patients with visual acuity worse than 20/200 at diagnosis had final visual acuity of worse than 20/200. Two-thirds of patients with hypopyon at diagnosis had final visual outcomes worse than 20/200, whereas less than one-third of patients without hypopyon at diagnosis had final visual acuity worse than 20/200. There was no significant difference in outcomes for patients undergoing vitrectomy compared with those treated with intravenous antibiotics or antifungal agents. Vitrectomy was not performed for our patient due to unfavourable risk-to-benefit ratio. The risk of amblyopia is minimal and the patient was responding well to the combination of intravitreal voriconazole and systemic amphotericin B.