Neutropenia, from Latin
prefixA prefix is an affix which is placed before the root of a word. Particularly in the study of languages,a prefix is also called a preformative, because it alters the form of the words to which it is affixed.Examples of prefixes:...
neutro- (neither, for neutral staining) and
GreekGreek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
suffixIn linguistics, a suffix is an affix which is placed after the stem of a word. Common examples are case endings, which indicate the grammatical case of nouns or adjectives, and verb endings, which form the conjugation of verbs...
-πενία (deficiency), is a granulocyte disorder characterized by an abnormally low number of neutrophils, the most important type of
white blood cellWhite blood cells, or leukocytes , are cells of the immune system involved in defending the body against both infectious disease and foreign materials. Five different and diverse types of leukocytes exist, but they are all produced and derived from a multipotent cell in the bone marrow known as a...
. Neutrophils usually make up 50-70% of circulating white blood cells and serve as the primary defense against
infectionAn infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
s by destroying
bacteriaBacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
in the
bloodBlood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....
. Hence, patients with neutropenia are more susceptible to bacterial infections and, without prompt medical attention, the condition may become life-threatening (neutropenic sepsis).
Neutropenia, from Latin
prefixA prefix is an affix which is placed before the root of a word. Particularly in the study of languages,a prefix is also called a preformative, because it alters the form of the words to which it is affixed.Examples of prefixes:...
neutro- (neither, for neutral staining) and
GreekGreek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
suffixIn linguistics, a suffix is an affix which is placed after the stem of a word. Common examples are case endings, which indicate the grammatical case of nouns or adjectives, and verb endings, which form the conjugation of verbs...
-πενία (deficiency), is a granulocyte disorder characterized by an abnormally low number of neutrophils, the most important type of
white blood cellWhite blood cells, or leukocytes , are cells of the immune system involved in defending the body against both infectious disease and foreign materials. Five different and diverse types of leukocytes exist, but they are all produced and derived from a multipotent cell in the bone marrow known as a...
. Neutrophils usually make up 50-70% of circulating white blood cells and serve as the primary defense against
infectionAn infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
s by destroying
bacteriaBacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
in the
bloodBlood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....
. Hence, patients with neutropenia are more susceptible to bacterial infections and, without prompt medical attention, the condition may become life-threatening (neutropenic sepsis).
Neutropenia can be acute or
chronicA chronic disease is a disease or other human health condition that is persistent or long-lasting in nature. The term chronic is usually applied when the course of the disease lasts for more than three months. Common chronic diseases include asthma, cancer, diabetes and HIV/AIDS.In medicine, the...
depending on the duration of the illness. A patient has chronic neutropenia if the condition lasts for longer than three months. It is sometimes used interchangeably with the term
leukopeniaLeukopenia is a decrease in the number of white blood cells found in the blood, which places individuals at increased risk of infection....
("deficit in the number of white blood cells"), as neutrophils are the most abundant leukocytes, but neutropenia is more properly considered a subset of leukopenia as a whole.
There are numerous causes of neutropenia that can roughly be divided between either problems in the production of the cells by the
bone marrowBone marrow is the flexible tissue found in the interior of bones. In humans, bone marrow in large bones produces new blood cells. On average, bone marrow constitutes 4% of the total body mass of humans; in adults weighing 65 kg , bone marrow accounts for approximately 2.6 kg...
and destruction of the cells elsewhere in the body. Treatment depends on the nature of the cause, and emphasis is placed on the prevention and treatment of infection.
Classification
There are three general guidelines used to classify the severity of neutropenia based on the
absolute neutrophil countAbsolute neutrophil count is a measure of the number of neutrophil granulocytes present in the blood...
(ANC) measured in cells per microliter 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.
Signs and symptoms
Neutropenia can go undetected, but is generally discovered when a patient has developed severe
infectionAn infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
s or
sepsisSepsis is a potentially deadly medical condition that is characterized by a whole-body inflammatory state and the presence of a known or suspected infection. The body may develop this inflammatory response by the immune system to microbes in the blood, urine, lungs, skin, or other tissues...
. Some common infections can take an unexpected course in neutropenic patients; formation of
pusPus is a viscous exudate, typically whitish-yellow, yellow, or yellow-brown, formed at the site of inflammatory during infection. An accumulation of pus in an enclosed tissue space is known as an abscess, whereas a visible collection of pus within or beneath the epidermis is known as a pustule or...
, for example, can be notably absent, as this requires circulating neutrophil granulocytes.
Some common symptoms of neutropenia include
feverFever is a common medical sign characterized by an elevation of temperature above the normal range of due to an increase in the body temperature regulatory set-point. This increase in set-point triggers increased muscle tone and shivering.As a person's temperature increases, there is, in...
s and frequent infections. These infections can result in conditions such as mouth ulcers,
diarrheaDiarrhea , also spelled diarrhoea, is the condition of having three or more loose or liquid bowel movements per day. It is a common cause of death in developing countries and the second most common cause of infant deaths worldwide. The loss of fluids through diarrhea can cause dehydration and...
, a burning sensation when urinating, unusual redness, pain, or
swellingIn medical parlance, swelling is the transient enlargement or protuberance in the body and may include tumors. According to cause, it may be congenital, traumatic, inflammatory, neoplastic or miscellaneous....
around a wound, or a
sore throatA sore throat or throat pain is a common physical symptom usually caused by acute pharyngitis, or throat inflammation, though it also occurs in a number of other situations, such as post trauma and in diphtheria. It can cause mild to extreme pain....
.
Diagnosis
Low neutrophil counts are detected on a full blood count. Generally, other investigations are required to arrive at the right diagnosis. When the diagnosis is uncertain, or serious causes are suspected,
bone marrow biopsyBone marrow examination refers to the pathologic analysis of samples of bone marrow obtained by bone marrow biopsy and bone marrow aspiration. Bone marrow examination is used in the diagnosis of a number of conditions, including leukemia, multiple myeloma, lymphoma, anemia, and pancytopenia...
is often necessary.
Other investigations commonly performed: serial neutrophil counts for suspected
cyclic neutropeniaCyclic neutropenia is a form of neutropenia that 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....
, tests for antineutrophil antibodies,
autoantibodyAn autoantibody is an antibody manufactured by the immune system that is directed against one or more of the individual's own proteins. It is derived from the Greek "auto" which means "self", "anti" which means "against" and "body"...
screen and investigations for
systemic lupus erythematosusSystemic lupus erythematosus , often abbreviated to SLE or lupus, is a systemic autoimmune disease that can affect any part of the body. As occurs in other autoimmune diseases, the immune system attacks the body's cells and tissue, resulting in inflammation and tissue damage...
,
vitamin B12Vitamin B12, vitamin B12 or vitamin B-12, also called cobalamin, is a water-soluble vitamin with a key role in the normal functioning of the brain and nervous system, and for the formation of blood. It is one of the eight B vitamins...
and folate assays and acidified serum (
Ham'sParoxysmal nocturnal hemoglobinuria , sometimes referred to as Marchiafava-Micheli syndrome, is a rare, acquired, potentially life-threatening disease of the blood characterised by complement-induced intravascular hemolytic anemia , red urine and thrombosis...
) test.
Causes
Causes can be divided into the following groups:
- Decreased production in the bone marrow
Bone marrow is the flexible tissue found in the interior of bones. In humans, bone marrow in large bones produces new blood cells. On average, bone marrow constitutes 4% of the total body mass of humans; in adults weighing 65 kg , bone marrow accounts for approximately 2.6 kg...
due to:
- aplastic anemia
Aplastic anemia is a condition where bone marrow does not produce sufficient new cells to replenish blood cells. The condition, per its name, involves both aplasia and anemia...
- arsenic poisoning
Arsenic poisoning is a medical condition caused by increased levels of the element arsenic in the body. Arsenic interferes with cellular longevity by allosteric inhibition of an essential metabolic enzyme...
- cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
, particularly blood cancers
- certain medications
- hereditary disorders (e.g. congenital neutropenia
Kostmann syndrome, also known as severe congenital neutropenia, autosomal recessive type 3 and Kostmann disease, is a rare autosomal recessive form of severe chronic neutropenia usually detected soon after birth...
, cyclic neutropeniaCyclic neutropenia is a form of neutropenia that 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....
)
- radiation
In physics, radiation is a process in which energetic particles or energetic waves travel through a medium or space. There are two distinct types of radiation; ionizing and non-ionizing...
- Vitamin B12
Vitamin B12, vitamin B12 or vitamin B-12, also called cobalamin, is a water-soluble vitamin with a key role in the normal functioning of the brain and nervous system, and for the formation of blood. It is one of the eight B vitamins...
, folate or copperCopper is an essential trace element that is vital to the health of all living things . In humans, copper is essential to the proper functioning of organs and metabolic processes. The human body has complex homeostatic mechanisms which attempt to ensure a constant supply of available copper, while...
deficiency.
- Increased destruction:
- autoimmune neutropenia
Autoimmune neutropenia is a form of neutropenia which is most common in infants and young children where the body identifies the neutrophils as enemies and makes antibody to destroy them....
.
- chemotherapy
Chemotherapy is the treatment of cancer with an antineoplastic drug or with a combination of such drugs into a standardized treatment regimen....
treatments, such as for cancer and autoimmune diseases
- Marginalisation and sequestration:
- Hemodialysis
In medicine, dialysis is a process for removing waste and excess water from the blood, and is primarily used to provide an artificial replacement for lost kidney function in people with renal failure...
- Medications
- such a Flecainide
Flecainide acetate is a class Ic antiarrhythmic agent used to prevent and treat tachyarrhythmias . It is used to treat a variety of cardiac arrhythmias including paroxysmal atrial fibrillation , paroxysmal supraventricular tachycardia Flecainide acetate is a class Ic antiarrhythmic agent used to...
(a class 1C cardiac anti-arrhythmic drug)
There is often a mild neutropenia in viral infections. Additionally, there is a condition called
morning pseudoneutropeniaMorning pseudoneutropenia is a transient reduction in the measured neutrophil count from peripheral samples. This is noticed in some patients who are taking antipsychotic medication...
which might be a side effect of certain anti-psychotic medications.
Therapy
There is no ideal therapy for neutropenia, but recombinant G-CSF (granulocyte-colony stimulating factor) such as
filgrastimFilgrastim is a granulocyte colony-stimulating factor analog used to stimulate the proliferation and differentiation of granulocytes. It is produced by recombinant DNA technology. The gene for human granulocyte colony-stimulating factor is inserted into the genetic material of Escherichia coli. ...
can be effective in chemotherapy patients, in patients with congenital forms of neutropenia including severe congenital neutropenia, autosomal recessive Kostmann's syndrome, cyclic neutropenia, and myelokathexis.
History
The relationship between a low neutrophil count and increased risk of infection was first demonstrated in patients with
leukemiaLeukemia or leukaemia is a type of cancer of the blood or bone marrow characterized by an abnormal increase of immature white blood cells called "blasts". Leukemia is a broad term covering a spectrum of diseases...
.
Diet
Guidelines given to neutropenic patients regarding diet are currently being studied. As of 2011, the Neutropenic Diet Guideline includes the following recommendations:
- Avoid raw vegetables and fruit.
- Avoid take-out foods and fast foods and fountain drinks.
- Avoid aged cheese.
- Cook all produce to well done. Eggs must be hard-boiled.
- Avoid deli meats.
- No raw nuts, nuts roasted in shell, or freshly ground nutbutters from a healthfood store.
- No well water
- No yogurt
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