is a
Hematological disorder characterized by an abnormally low number of
Neutrophil Granulocytes (a type of
White Blood Cell ). Neutrophils usually make up 50-70% of circulating white blood cells and serve as the primary defence against
Infections by destroying
Bacteria in the
Blood . Hence, patients with neutropenia are more susceptible to bacterial infections and without prompt medical attention, the condition may become life-threatening. Neutropenia can be
Acute or
Chronic depending on the duration of the illness. A patient has chronic neutropenia if the condition lasts for greater than 3 months. It is sometimes used interchangably with the term
Leukopenia . However, neutropenia is more properly considered a subset of leukopenia as a whole.
There are four general guidelines used to classify the severity of neutropenia based on the absolute neutrophil count (ANC) measured in cells per
Microlitre of blood:
- Neutropenia (ANC < 2000) — slight risk of infection
- 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.
Severe chronic neutropenia may be present at birth (congenital neutropenia) or may occur at any stage in life (acquired neutropenia).
There are four main types of severe chronic neutropenia:
— a rare inherited form of the disease usually detected soon after birth. It affects children mainly and may result in premature loss of teeth and peremptory gum infections. The most severe form of chronic congenital neutropenia is known as
Kostmann’s Syndrome .
— tends to occur every three weeks and lasting three to six days at a time due to changing rates of cell production by the bone marrow. It is often present among several members of the same family although improves after puberty in most cases. This is the rarest form of severe chronic neutropenia.
— a rare form of neutropenia which develops in children and adults usually in response to an illness. It is diagnosed when the disorder cannot be attributed to any other diseases and often causes life-threatening infections.
— most common in infants and young children where the body identifies the neutrophils as enemies and makes
Antibody to destroy them. This form usually lessens in severity within two years of
Diagnosis .
— Many drugs can cause agranulocytosis (complete absence of white cells) and neutropenia. Many
Anti-neoplastic Drugs cause agranulocytosis and neutropenia by bone marrow suppression. Neutropenia and agranulocytosis can also result from
Antibody or
Complement -mediated damage to the stem cells. Some drugs may cause increased peripheral destruction of white cells. About 75% of all cases of agranulocytosis in the United States are related to medication.
Clozapine ,
Procainamide , anti-thyroid drugs (e.g.
Methimazole , and
Sulfasalazine are at the top of the list of drugs causing this problem, but many others (such as
Antiepileptic s) have been implicated.
Causes can be divided into the following groups:
There is usually a mild neutropenia in
Viral Infection s.
Neutropenia can go undetected, but is generally discovered when a patient has developed severe
Infection s or
Sepsis . Some common infections can take an unexpected course in neutropenic patients; formation of
Pus , for example, can be notably absent, as this requires circulating neutrophil granulocytes.
Some common symptoms of neutropenia include:
Low neutrophil counts are detected on a
Full Blood Count . Generally, some other investigations are required to arrive at the right diagnosis. When the diagnosis is uncertain, or serious causes are suspected,
Bone Marrow Biopsy is often necessary.
There is no ideal therapy for neutropenia, but recombinant
G-CSF (granulocyte-colony stimulating factor) can be effective in chemotherapy patients and some other causes.
