Febrile Neutropenia: Pathogenesis and clinical findings (Cytotoxic) Chemotherapy
Authors: Max Lazar Reviewers: Naman Siddique Lynn Savoie* * MD at time of publication
Acquired and Congenital Conditions (AA, SCN etc.)
Medications
(e.g. Immunosuppressants, Atypical antipsychotics)
Neutropenia: ANC < 0.5x109/L Impaired blood cell formation Chemotherapy -induced GI mucosal injury Damaged barrier to infection Indwelling catheters needed to deliver treatment ↑ access to tissues for skin colonizing bacteria Altered GI bacterial flora Some species eliminated while others leftover Lack of competition leads to overgrowth of surviving species Normally commensal species act opportunistically Positive tissue cultures ↓ phagocytosis of microbes ↓ production of inflammatory mediators Blunted immune response Dormant infections reactivate (CMV, HSV, etc.) ↑susceptibility to common infections (UTI, Pneumonia, etc.) Definitions: • Phagocytosis: Engulfing of pathogens by immune cells • Opportunistic pathogen: a species that is normally not pathogenic but can be, in certain situations • Commensal: bacterial species that provide benefits to their human host Penetration of Physical Barriers Pathogen invasion from tissue (GI, GU, etc.) Pathogen invades bloodstream Systemic infection Fever: T ≥ 38.3C or sustained T ≥ 38C Abbreviations: • AA – Aplastic Anemia • SCN – Severe Congenital Neutropenia • ANC – Absolute Neutrophil Count • CMV – Cytomegalovirus • HSV – Herpes Simplex Virus • GI – Gastrointestinal • GU – Genitourinary Legend: Pathophysiology Mechanism Sign/Symptom/Lab Finding Complications Published December 5, 2018 on www.thecalgaryguide.com