TY - CHAP M1 - Book, Section TI - Approach to Infection in Patients Receiving Cytotoxic Chemotherapy for Malignancy A1 - Bow, E. J. A2 - Hall, Jesse B. A2 - Schmidt, Gregory A. A2 - Kress, John P. Y1 - 2015 N1 - T2 - Principles of Critical Care, 4e AB - Risk of infection increases as the circulating absolute neutrophil count (ANC) declines below 1.0 and 0.5 × 109/L. The greatest risk of bacteremic infection occurs when the ANC is 0.5 × 109/L) can vary from 21 to 42 days.Intermittent administration of cytotoxic therapy for solid tissue malignancies or lymphoreticular malignancies (low-risk patients) is often associated with a neutrophil nadir at 10 to 14 days from beginning treatment and with periods of neutropenia (ANC <0.5 × 109/L) of less than 5 to 7 days. This pattern of neutrophil recovery influences the natural history of febrile neutropenic episodes.Febrile episodes during neutropenia are defined by an oral temperature of ≥38.3°C (100°F) in the absence of other noninfectious causes of fever such as administration of blood products or pyrogenic drugs (eg, cytotoxic therapy, amphotericin B), the underlying disease, thromboembolic or thrombophlebitic events, or hemorrhagic events.A single neutropenic episode may be characterized by one or more febrile episodes, of which one or more may represent infections.Body sites most often associated with infection in the neutropenic patient are those associated with integumental surfaces (skin, upper and lower respiratory tract, and upper and lower gastrointestinal tract).Antibacterial prophylaxis with oral fluoroquinolone agents such as ciprofloxacin or levofloxacin can reduce the frequency of febrile episodes and bacteremic events in patients with protracted neutropenia.Patients undergoing remission induction for acute myeloid leukemia or bone marrow transplantation with a history of herpetic stomatitis or who are IgG seropositive for herpes simplex virus (HSV) are at risk for severe herpetic mucositis. Such patients should be considered for oral nucleoside analogue-based antiviral prophylaxis.The recommended initial empirical antibacterial therapy for suspected infection in the febrile neutropenic patient is a broad-spectrum antibacterial regimen of an antipseudomonal penicillin or carbapenem administered as a single agent (monotherapy). Additional initial antibacterial agents such as aminoglycosides, fluoroquinolones, or vancomycin may be indicated for the initial management of severe sepsis/septic shock, pneumonia, or where antimicrobial resistance is suspected.The median time to defervescence for febrile neutropenic patients at low- and high-risk for medical complications is 3 and 5 days, respectively. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - accesssurgery.mhmedical.com/content.aspx?aid=1107720533 ER -