Neutropenic Fever: Understanding, Managing, and Preventing a Critical Complication

By Anne Denk, RN, BSN

People often have a fever when they are sick. A fever is a tool the immune system uses to fight off infection. Neutropenic fever occurs in individuals with a low neutrophil count. Neutrophils are the most common type of white blood cell. Neutrophils are the first cells that attack foreign intruders in the body. They fight off infection. When someone has a low neutrophil count and a fever, it is referred to as “neutropenic fever.” Many things can cause this condition. Different treatments are prescribed based on the cause of infection and the individual’s medical condition.

Presentation of Neutropenic Fever

A low level of neutrophils is called “neutropenia.” People with an absolute neutrophil count (ANC) of <1500 cells/mcL are “neutropenic.” A person who has a low ANC has a “neutropenic fever” when their temperature is:

·       101°F (38°C), or

·       greater than/equal to 100.4°F (38°C) for one hour or more

People with a low immune system are at risk of developing a neutropenic fever. This group of people can include those with chronic infections. It also includes people who take medications that purposefully lower their immune system to treat a different medical condition. These situations can cause a drop in neutrophil levels. These people are more vulnerable to infections.

People at risk for Neutropenic Fever

People with cancer often receive chemotherapy as treatment. A common side effect of chemotherapy is neutropenic fever. Chemotherapy targets rapidly dividing cells, such as cancer. However, chemotherapy also destroys helpful rapidly dividing cells, such as neutrophils.

Chemotherapy can break down the mucus membrane. The mucus membrane provides an added layer of protection in the nasal passageways, lungs, and GI tract. When this protective membrane is damaged, bacteria can enter the body’s system more easily. When a person has a low neutrophil count and a damaged mucus membrane, it is more difficult for their immune system to fight off bacteria and infection.

Some medications, other than chemotherapy, can lower the neutrophil count. Some of these medications include:

·       antibiotics

·       antimalarials

·       anti-inflammatory drugs

·       psychotropics

·       antithyroid drugs

·       cardiovascular drugs

·       anti-seizure drugs

Nutritional deficiencies can also lower neutrophil counts. Copper, vitamin B12, and folate help develop cells, such as neutrophils. When these nutrient levels are low, the body cannot produce neutrophils efficiently.

Some people have a low immune system due to other conditions. Human immunodeficiency virus (HIV) is a virus that attacks the immune system. This can slow the growth of immune cells such as neutrophils. People with autoimmune diseases, such as lupus or rheumatoid arthritis, are also at risk for this condition. These diseases cause the body to attack its own tissues and cells.

Treatment

Before starting treatment, blood and urine samples are collected. They are then processed to identify the specific type of bacteria. This can take a couple of days or longer. While waiting for results, treatment is started.

Empiric Antibiotics

Antibiotics are used to treat neutropenic fever. The first type of antibiotics given are “empiric” antibiotics. Think of these as “general” antibiotics. These medications wipe out most types of bacteria. Low-risk patients are started on oral antibiotics at home. High-risk patients are admitted to the hospital and started on intravenous (IV) antibiotics.

Targeted Antibiotics

When the blood and urine culture results are complete, new antibiotics might be started. Antibiotics that target specific types of bacteria are used to treat neutropenic fever. This stops the infection and stops the fever.

Drug-Resistant Bacteria

Some bacteria learn to resist standard antibiotics. The antibiotics are no longer effective in destroying these bacterial cells. This type of bacteria is “drug-resistant.” The most common types of drug-resistant bacteria include:

·       Methicillin-resistant Staphylococcus aureus (MRSA)

·       Vancomycin-resistant enterococci (VRE)

·       Extended-spectrum beta-lactamase (ESBL)-producing organisms

·       Klebsiella pneumoniae

When drug-resistant bacteria are identified, alternative antibiotics are added. These antibiotics might be given in pill or IV form. They are ordered for several days or weeks to fight off the specific type of drug-resistant bacteria.

Complications

If left untreated, neutropenic fever can progress to sepsis. Sepsis is a severe reaction of the immune system to an infection. It includes extensive inflammation. It can cause damage to tissue, organs, and potentially lead to death. It is important to follow doctor’s orders to avoid progressing to a state of sepsis.

Preventing Neutropenic Fever

People with a low neutrophil count can take extra steps to prevent a neutropenic fever. Based on a person’s medical history, their doctor might prescribe preventive medications. These medications might include antibiotics, antifungals, and/or antivirals. These are ordered for a certain amount of time while neutrophil counts are low. They usually are discontinued once the neutrophils return to a safer level.

Doctors order labs regularly to monitor neutrophil levels. If a person is aware that they have a low ANC (<1500 cells/mcL), they should check their temperature daily. If the ANC is <1000, they can protect themselves by staying home and avoiding large crowds. When they must be outside of the home, they need to wear a mask to reduce the risk of exposure to illness.

Ongoing Education and Follow-Up

People with a low neutrophil count benefit from ongoing discussions with and education from their doctor. Recommendations for precautions and treatment vary from person to person. The doctor who is following a person for low neutrophil counts will be the best person to review their options. This doctor is familiar with the individual’s neutrophil trends in addition to their other medical history. People with low neutrophil counts should talk to their doctor to identify the best steps for preventing, monitoring, and treating neutropenic fever.

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