MDM Templates

Neutropenic Fever

Patient with history of *** and recent chemotherapy presents with fever. Given the underlying oncological process and recent cytotoxic therapy, this patient is at high risk for neutropenia with evolving bacteremia or sepsis. Febrile neutropenia is a medical emergency requiring empiric broad-spectrum antibiotics within 60 minutes of presentation.

History and exam do not identify a clear source of infection, though the absence of a source does not lower concern in a neutropenic patient, as they lack the inflammatory response to localize infection. Clinical assessment focused on identifying occult sources including oral mucosa, perianal region, skin, and indwelling lines.

Plan: Empiric cefepime 2g IV administered within 60 minutes. Oncology contacted for further guidance.
Disposition: Admit for continued broad-spectrum antibiotics, serial monitoring, and neutrophil recovery.

If not neutropenic (ANC >500):
Reassess for alternative sources of fever. Consider ceftriaxone and possible discharge with oncology guidance if well-appearing without concerning source.

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Febrile Oncology Patient — Not Neutropenic

Patient with history of *** and recent chemotherapy presents with fever. ANC is >500, indicating preserved neutrophil function. Patient is well appearing without hemodynamic instability or signs of severe sepsis.

Despite adequate neutrophil count, febrile oncology patients remain higher risk than the general population due to immunosuppression, mucosal disruption, and indwelling hardware. History and exam assessed for catheter-related infection, mucositis, perianal abscess, and pneumonia.

Plan: Source-directed workup and treatment. Oncology consulted regarding disposition.
Disposition: Per oncology guidance — discharge with close follow-up if low-risk features, admit if high-risk or unclear source.

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Clinical Education

Antibiotic Selection

Cefepime 2g IV is the empiric standard for febrile neutropenia. It provides broad gram-negative coverage including Pseudomonas, which is the lethal organism you’re covering for. Time to antibiotics matters — treat within 60 minutes of presentation, before lab confirmation of neutropenia.^[1]

Scenario	Antibiotic
Standard empiric	Cefepime 2g IV q8h
Penicillin allergy (non-anaphylactic)	Cefepime (cross-reactivity risk is <2%)
Severe penicillin allergy or prior ESBL	Meropenem 1g IV q8h
Add vancomycin if:	Hemodynamic instability, skin/soft tissue infection, MRSA history, catheter-related infection suspected, mucositis with fluoroquinolone prophylaxis

Avoid ertapenem — it lacks adequate Pseudomonal coverage. If you need a carbapenem, use meropenem.^[1]

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Risk Stratification (MASCC Score)

The MASCC Score helps identify low-risk patients who may be candidates for outpatient management. Score >21 indicates low risk (predicted <5% serious complication rate). However, outpatient management of febrile neutropenia requires oncology buy-in, reliable follow-up, and the ability to return within 1 hour if deteriorating.^[2]

Practical pearl: Most emergency physicians admit febrile neutropenia patients regardless of MASCC score, and this is reasonable. The MASCC is most useful when oncology is pushing for discharge — it helps frame the conversation around risk.

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Blasts on CBC

It is NEVER normal to see blasts on a peripheral smear. Even a small percentage of blasts warrants further evaluation including hematology consultation and likely bone marrow biopsy. The significance depends on context:^[3]

Finding	Significance
Blasts >20% on peripheral smear	Diagnostic threshold for AML
Bands >5-10%	“Left shift” — associated with serious bacterial infection, but can also occur with viral illness and stress
Immature cells up to myelocyte stage	Leukemoid reaction — reactive to infection or stress, not malignancy (usually)

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Special Situations

Perianal infections in neutropenic patients: Do NOT perform a rectal exam or place a rectal thermometer in severely neutropenic patients. Perianal cellulitis or abscess in this population requires admission, broad-spectrum antibiotics, and surgical consultation. Incision and drainage is often deferred until neutrophil recovery.

Typhlitis (neutropenic enterocolitis): RLQ pain and fever in a neutropenic patient. Can mimic appendicitis. Diagnosed by CT showing bowel wall thickening (usually cecum). Managed with bowel rest, broad-spectrum antibiotics, and surgery consultation. Avoid colonoscopy (perforation risk).^[1]

G-CSF (filgrastim): Accelerates neutrophil recovery. Decision to administer is made by oncology, not typically initiated in the ED.

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References

1. Taplitz RA et al. Outpatient Management of Fever and Neutropenia in Adults Treated for Malignancy: ASCO and IDSA Clinical Practice Guideline Update. J Clin Oncol. 2018;36(14):1443-1453. PubMed
2. Klastersky J et al. The MASCC Risk Index Score: 10 Years of Use for Identifying Low-Risk Febrile Neutropenic Cancer Patients. Support Care Cancer. 2013;21(5):1487-1495. PubMed
3. George TI. Malignant or Benign Leukocytosis. Hematol Am Soc Hematol Educ Program. 2012;2012:475-484. PubMed