Neutropenia

Neutropenia is "a decrease in the number of neutrophilic leukocytes in the blood."

The half-life of a neutrophil is less than one-half of a day.

Diagnosis

Grading

Grading is:

• Grade 1: < 2.0 x 10⁹/L (< 2000/mm³) and > 1.1 x 10⁹/L (> 1500/mm³)
• Grade 2: < 1.5 x 10⁹/L (< 1500/mm³) and > 1.0 x 10⁹/L (> 1000/mm³)
• Grade 3: < 1.0 x 10⁹/L (< 1000/mm³) and > 0.5 x 10⁹/L (> 500/mm³)
• Grade 4: < 0.5 x 10⁹/L (< 500/mm³)

Or the Following

There are three general guidelines used to classify the severity of neutropenia based on the absolute neutrophil count (ANC) measured in cells per micro liter of blood:

• Mild neutropenia (1000 < ANC < 1500) — minimal risk of infection • Moderate neutropenia (500 < ANC < 1000) — moderate risk of infection • Severe neutropenia (ANC < 500) — severe risk of infection. • NOTE: These are ranges for Caucasians. Neutropenia in black individuals is defined as ANC < 1200. The following information is from WikiDoc.

For ease of reading the following measurements can be written as:

• Mild neutropenia ranges between 1,000 to 1,500 absolute neutrophil count (ANC) measured in cells per micro liter of blood. There is a minimal risk of infection.
• Moderate neutropenia ranges between 500 to 1,000 absolute neutrophil count (ANC) measured in cells per micro liter of blood. There is a moderate risk of infection.
• Severe neutropenia is less than absolute neutrophil count (ANC) measured in cells per micro liter of blood. There is a severe risk of infection.

Neutropenia is more commonly found in women and the elderly.

Benign ethnic neutropenia has been observed in Africans African-Caribbean persons West Indians Ethiopians, Yemenite Jews and certain Arabs, according to the Annals of Internal Medicine.

Causes

There are many causes of neutropenia. Some causes are caused by infections while others are not. Some causes of neutropenia may include Acquired Immune Deficiency Syndrome (AIDS), influenza, typhus, malaria, tuberculosis, dengue, Rickettsial infections, systemic lupus erythematosus, Sjogren’s Syndrome, Felty’s Syndrome, Kostmann Syndrome, enlargement of the spleen, folate deficiencies and sepsis, according to WikiDoc.

Kostmann Syndrome, Cyclic Neutropenia, Idiopathic Neutropenia and autoimmune neutropenia are considered rare medical disorders of the blood. Patients may register with the Severe Chronic Neutropenia Registry (SCNIR) founded in 1994 to monitor the clinical course, treatment and disease outcomes of registered patients.

The following information is from SCNIR:

Kostmann Syndrome, known as Congential neutropenia, is rare neutropenia found at birth. It is an inherited disease and can affect more than one family member. Congenital neutropenia, often also called Kostmann syndrome is a rare type of neutropenia that is present at birth. It is an inherited disease and therefore, more than one family member can be affected, but sporadic occurrence with only one patient in a family may occur. There is no prenatal testing available to check for Kostmann Syndrome. Children affected by Kostmann Syndrome are usually severe and children may have no neutrophils present in the blood. Neutrophils typically are in an arrested state of development or maturation arrest in the bone marrow. The neutrophils rarely mature to full stage development leaving the patient incapable of fighting off infection. Diagnosis is usually made during infancy.

Cyclic neutropenia is another inherited blood disorder. Neutrophil activity runs in cycles, typically 21 days, and range from normal blood counts to low blood counts. It is common for the ANC to drop to less than 200 cells/µl) (0.2 x 109/l). Common symptoms during the low period of the cycle may include mouth ulcers and inflammation. Severe infections such as otitis media (ear infections), pneumonia and bacteraemia (blood infections) are less likely to be seen.

Patients suspected of Cyclic neutropenia go through a specific type of testing to determine if they have Cyclic neutropenia.

“Cyclic neutropenia occurs because of fluctuating rates of cell production by the bone marrow stem cells”

Idiopathic neutropenia includes many types of neutropenia and can happen at any point in life for unknown reasons. It can occur in both adults and children and the effects are variable based on disease severity.

Autoimmune neutropenia is found in children between six months and four-years-old that have not been diagnosed with congenital neutropenia. This is the most common cause of neutropenia for children in this age group. Severe bacterial infections are rare. Autoimmune neutropenia may also be found in adults, who are usually between the ages of 20 to 40, and most commonly women. This condition is usually associated with other medical conditions.

Other medical conditions or medicines may cause neutropenia. Cancer patients undergoing chemotherapy could develop neutropenia.

Febrile neutropenia

Clinical practice guidelines define febrile neutropenia as "a single oral temperature of >=38.3°C (101°F) or a temperature of >=38.0°C (100.4°F) for >= 1 h. Neutropenia is defined as a neutrophil count of <500 cells/mm3, or a count of <1000 cells/mm3 with a predicted decrease to <500 cells/mm3"

A clinical prediction rule can estimate the risk of morbidity in the febrile patient with neutropenia. A score of >=21 indicates low risk.

Prevention

Hematopoietic colony-stimulating factors for primary prevention of febrile neutropenia may not decrease mortality but do decrease infections in patients undergoing cancer chemotherapy or stem cell transplantation according to a systematic review.

Granulocyte colony-stimulating factor is indicated in selected settings if the projected chance of febrile neutropenia is at least 20%.