الفهرس 
NeutropeniaOnly 14 pages are availabe for public view
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Abstract
Neutropenia is a granulocyte disorder characterized by an abnormally low number of neutrophils. Neutrophils usually make up 50-70% of circulating white blood cells and serve as the primary defense against infections by destroying bacteria in the blood. Hence, patients with neutorpenia are more susceptible to bacterial infections and, without prompt medical attention, the condition may become life-threatening (neutropenic sepsis).
Neutropenia can be acute or chornic 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 leucopenia (deficit in the number of white blood cells), as neutrophils are the most abundant leukocytes, but neutropenia is more properly considered a subset of leucopenia as a whole.
The diagnosis of neutropenia is based on a low blood neutrophil concentration. The blood neutrophil count can be calculated readily from a routine compelte blood count as follows: Blood neutrophil count = White cells (ml) x % neutrophils on the differential count. The percent neutrophils generally are considered the sum of the segmented neutrophils, band neutorphils, and metamyelocytes.
There are three general guidelines used to classify the severity of neutropenia based on the Absolute Neutrophil Count (ANC) measured in ells 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.
Neutropenia can go undetected, but is generally discovered when a patient has developed severe infections or sepsis. Some common infections can take an unexpected course in neutropenic patients; for example, formation of pus can be notably absent, as this requires circulating neutrophil granulocytes.
In the last two decades, Candida has emerged as an important opportunistic pathogen. Patients admitted to the Intensive Care Unit (ICU) are particularly susceptible to this infection because of the severity of their underlying illness and the excess use of medical and surgical interventions.
Some common symptoms of neutropenia include fevers and frequent infections. These infections can result in conditions such as mouth ulcers, diarrhea, a burning sensation when urinating, unusual redness, pain, or swelling around a wound, or sore throat.
The incidence of infection varies greatly between different types of ICUs. Among Surgical ICUs (SICUs), the candidaemia rate can vary as much as 0.5-1.73 per 1000 patient days.
In general, ICUs caring for high-risk patients such as abdominal surgical or immunosuppressed patients have a higher incidence of invasive candidasis than general medical ICUs/SICUs as illustrated by the National Epidemiology of Mycosis Survey study. He difference in infection rates is mainly due to the patient case mix and risk factors, but may also be influenced by the specific management of the infection in particular units.
There are numerous causes of neutropenia that can roughly be divided between either problems in the production of the cells by the bone marrow and destruction of the cells elsewhere in the body. Also, there are a number of well-described general risk factors such as old age, very low birth weight in premature neonates, diabetes mellitus and immunosuppression.
Also, some varities of neutropenia in the Neonatal Intensive Care Unit (NICU) are very common and other sare extremely rare. The most common causes of neutropenia in the NICU have an underlying cause that is often evident, and require little diagnostic evaluation.
Unlike, persistent neutropenia which need prompt evaluation even if it is of moderate severity. The laboratory tests needed are those that provide a specific diagnosis. First, blood film should be ordered then a complete blood count on the mother, and, if her blood neutrophil concentration is normal, maternal neutrophil antigen typing and an anti-neutrophil antibody screen. A bone marrow biopsy can be useful in cases with prolonged, unusual, or refractory neutropenia.
Treatment depends on the nature of the cause, and emphasis is placed on the prevention and treatment of infection. Various treatments have been proposed as means of enhancing neutrophil production and function in preterm infants. Both recombinant granulocyte stimulating factor and recombinant granulocyte macrophage-colony-stimulating factor have been tried with variable success. Intravenous immunoglobulin, corticosteroids, granulocyte transfusions, and gamma interferon did not show a clear adequate beneficial role for the therapy of neonatal neutropniea.
The frequent use of antibiotics, central venous catheters and other intravascular devices as well as poor gut motility or abdominal surgery place are considered high risk factors for infection, which contributes to the morbidity and mortality of the already critically ill patient. Early recognition and appropriate management of patients with neutropenia are therefore important.