Neutropenia is a low number of neutrophils, the white cells that fight bacteria and fungi, defined as an absolute neutrophil count under 1,500 per microliter. The lower the count and the longer it lasts, the higher the risk of infection, and fever with severe neutropenia is a medical emergency.
Key symptoms
- Fever, which may be the only sign of infection
- Mouth sores and sore throat
- Skin infections, cough or pain with urination
- Recent chemotherapy, a new medicine or a viral illness
What you find on exam
- Vital signs for sepsis: fever, fast heart rate, low blood pressure
- Mouth, throat, skin, lungs and IV or central line sites
- Perianal area by inspection only; no rectal exam or rectal thermometer
- Signs of infection can be subtle because there is little pus or inflammation
Tests
- Blood count with differential to calculate the absolute neutrophil count
- Blood cultures from a vein and each line lumen before antibiotics
- Urinalysis, urine culture and chest X-ray as guided by symptoms
- If not from chemotherapy: smear, B12 and folate, HIV, drug review, bone marrow if unexplained
Treatment basics
- Febrile neutropenia: broad-spectrum antibiotics such as cefepime or piperacillin-tazobactam within 1 hour
- Add vancomycin for line or skin infection, pneumonia or an unstable patient
- Granulocyte colony-stimulating factor (filgrastim) in selected patients
- Stop the drug if neutropenia is drug-induced
- Neutropenic precautions: hand hygiene, avoid sick contacts
Red flags
- Fever of 38.3 C or more, or 38.0 C for an hour, with severe neutropenia
- Low blood pressure, confusion or fast breathing: septic shock
- Severe mouth sores, abdominal pain or a red, painful line site
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.