From the Guidelines
Low neutrophils, also known as neutropenia, is a condition where the body has an abnormally low number of neutrophils, a type of white blood cell crucial for fighting infections, particularly bacterial and fungal infections, as stated in 1. Neutrophils play a vital role in providing host defense against infection, and a low count can increase the risk of infections, with the greatest risk occurring in patients who experience profound, prolonged neutropenia, as seen in patients undergoing cytotoxic chemotherapy and hematopoietic stem-cell transplantation (HSCT) 1. Some key points to consider about low neutrophils include:
- Normal neutrophil counts typically range from 1,500 to 8,000 cells per microliter of blood, and neutropenia is generally defined as a count below 1,500 1.
- The condition can be mild (1,000-1,500), moderate (500-1,000), or severe (below 500), with infection risk increasing as numbers decrease 1.
- Low neutrophils can result from various causes including certain medications (like chemotherapy drugs or antibiotics), viral infections, autoimmune disorders, bone marrow disorders, vitamin deficiencies, or genetic conditions.
- Treatment depends on the underlying cause and severity, ranging from monitoring for mild cases to antibiotics for infections, granulocyte colony-stimulating factors (G-CSF) like filgrastim for severe cases, or addressing the underlying condition, as the risk of infection increases with the depth and duration of neutropenia, with the greatest risk occurring in patients who experience profound, prolonged neutropenia 1. It is essential to practice good hygiene, avoid people with infections, cook food thoroughly, and seek medical attention promptly if you develop fever or signs of infection, as fever can be an important indicator of infection, although clinicians should also be mindful that severely or profoundly neutropenic patients may present with suspected infection in an afebrile state or even hypothermic 1.
From the FDA Drug Label
Low neutrophil counts are referred to as neutropenia, which is defined as an ANC < 1,000/mm3 and in severe cases < 500/mm3.
Low neutrophils mean that a patient has neutropenia, a condition characterized by an abnormally low number of neutrophils in the blood. Neutrophils are a type of white blood cell that plays a crucial role in fighting infections.
- Mild neutropenia: ANC between 1,000/mm3 and 1,500/mm3
- Severe neutropenia: ANC < 500/mm3 2
From the Research
Definition of Low Neutrophils
Low neutrophils, also known as neutropenia, refers to a condition where the number of neutrophils, a type of white blood cell, is lower than normal. Neutrophils play a crucial role in fighting infections, and a low count can increase the risk of infection and disease.
Causes of Neutropenia
Neutropenia can be caused by various factors, including:
- Chemotherapy, which can suppress the production of white blood cells, including neutrophils 3, 4, 5, 6, 7
- Bone marrow disorders, such as leukemia or lymphoma
- Autoimmune disorders, such as rheumatoid arthritis or lupus
- Infections, such as sepsis or tuberculosis
- Medications, such as antibiotics or anticonvulsants
Symptoms of Neutropenia
The symptoms of neutropenia can vary depending on the severity of the condition. Some common symptoms include:
- Fever
- Fatigue
- Weakness
- Pale skin
- Shortness of breath
- Increased risk of infection
Treatment of Neutropenia
Treatment for neutropenia depends on the underlying cause. In some cases, medications such as filgrastim or pegfilgrastim may be used to stimulate the production of white blood cells 3, 4, 5, 6, 7. In other cases, treatment may involve addressing the underlying condition, such as chemotherapy or an autoimmune disorder.
Importance of Neutrophil Count
A low neutrophil count can increase the risk of infection and disease. It is essential to monitor neutrophil counts, especially in patients undergoing chemotherapy or with underlying medical conditions. Studies have shown that prophylactic use of filgrastim and pegfilgrastim can reduce the risk of febrile neutropenia and improve patient outcomes 3, 4, 5, 6, 7.