To quantify the diagnostic, prognostic and therapeutic value of spectrometric analysis of exhaled breath from hematological patients with respiratory infection.

Inclusion Criteria:

• Age ≥ 18y at start of study

• One of the following diagnoses:

  • De novo, refractory or relapsed AML/MDS receiving intensive chemotherapy
  • De novo, refractory or relapsed ALL/T-lymphoblastic lymphoma receiving intensive chemotherapy
  • Aplastic anemia requiring ATG therapy
  • Any patient admitted for either autologous hematopoietic stem cell transplantation. Transplantation may not have been performed at time of enrolment.
  • Any patient admitted with allogeneic hematopoietic stem cell transplantation within the last year, or planned during this admission.

• Written informed consent obtained from the patient

Exclusion Criteria:

• Hematological disease beyond the specified inclusion criteria
• Signs of active respiratory infection
• If previously enrolled: incomplete clearance of all signs of respiratory infection (both clinically, microbiologically and radiologically).

Patients at high risk for opportunistic respiratory infections due to acute myeloid or lymphatic leukemia (undergoing intensive treatment), patients who underwent allogeneic stem cell transplantation, and patients receiving autologous stem cell transplantation