Administration of broad-spectrum antibiotics within hour of presentation to the ED has been shown to reduce morbidity and mortality from sepsis in the setting of neutropenia Digital rectal examinations and rectal temperature measurements should not be performed in neutropenic patients, as these procedures increase the risk of bacterial translocation from the intestinal tract into the bloodstream Though fever should raise concern for infection, the absence of fever does not exclude the possibility of infection, particularly in patients on high-dose steroids and/or with hypothalamic dysfunction from tumor Neutropenic patients may not generate erythema or purulence at the site of localized infections Current Evidence Fever in a neutropenic patient is a true emergency, even in a well-appearing patient ( Fig 98.4 ) Identification of infection can be challenging because typical symptoms may be absent or decreased The depth and duration of neutropenia helps to predict the risk of serious infections All patients with an ANC below 500 or with a rapidly falling ANC that will shortly be below 500 should be considered at risk Although fever itself can be a manifestation of some cancers, this is a diagnosis of exclusion, particularly in a patient with neutropenia While fever should certainly raise concern for infection, the absence of fever should not overly reassure the clinician Fever may be absent or minimized in patients on high-dose steroids and/or patients with hypothalamic dysfunction from tumor In addition, localizing signs of infection may be blunted because the lack of neutrophils prevents many of the usual manifestations such as pus, significant local erythema, or edema One of the infectious risks attributable to the immunosuppression of chemotherapy is Pneumocystis jirovecii (formerly known as Pneumocystis carinii ) pneumonia Patients younger than year and those receiving treatment for leukemia or high-stage lymphoma are at increased risk Most, if not all, pediatric oncology patients are treated with prophylactic trimethoprim-sulfamethoxazole to prevent this infection Those who not tolerate trimethoprim-sulfamethoxazole are on secondline agents such as atovaquone, dapsone, or pentamidine Prophylaxis for other infections varies by condition and center Fungal prophylaxis is increasingly common with specific regimens associated with a high frequency of fungal disease For example, many patients with acute myelogenous leukemia take prophylactic antifungals throughout their treatment Respiratory