Clinical Presentations of Pseudomonas aeruginosa Infection in Children with Leukaemia Treated with Chemotherapy—A Series of 5 Cases with Discussion

Background: Ecthyma gangrenosum (EG) associated with Pseudomonas aeruginosa can be life-threatening in immunocompromised patients with haematological malignancies. Severe neutropenia and antimicrobial resistance complicate treatment, while the roles of surgery and supportive therapies remain uncertain. Methods: We retrospectively reviewed five paediatric patients with leukaemia who developed life-threatening P. aeruginosa infections during chemotherapy. Cases were identified through a tertiary paediatric oncology centre’s clinical registry and verified using archived medical records. Clinical, microbiological, therapeutic, and outcome data, including surgical interventions, supportive therapies, and chemotherapy interruptions, were analysed. Results: All five patients developed severe infections during chemotherapy. EG affected the perineal or genital region in several cases, including two cases of Fournier’s gangrene. Four patients underwent surgical excision or debridement; surgery was not feasible in one because of critical deterioration. All received antimicrobials, with regimens adjusted according to microbiological findings and susceptibility profiles. Supportive treatments included granulocyte colony-stimulating factor, immunoglobulins, and granulocyte transfusions. Two patients survived into adulthood, including one who remained in remission after haematopoietic stem cell transplantation; three died, one from infection-associated multiorgan failure before surgery, one following leukaemia relapse, and one from post-transplant complications. Infection and its treatment substantially delayed or modified chemotherapy. Conclusions: EG associated with P. aeruginosa during paediatric leukaemia treatment can cause death and disrupt anticancer therapy. Early multidisciplinary assessment, appropriate antimicrobial treatment, and timely surgical management of necrotic tissue should be considered when feasible. Immunomodulatory interventions and discharge between chemotherapy cycles may benefit selected patients, but their efficacy cannot be established from this small retrospective series. Further multicentre studies are needed to clarify optimal management.