Symptoms
Infections that can cause neutropenia include: Tuberculosis. Dengue fever. Viral infections such as Epstein-Barr virus, cytomegalovirus, HIV, viral hepatitis.
Causes
White blood cells in general, and neutrophils in particular, are important for infection control in the body. Neutropenia can be classified as mild, moderate, or severe, depending on the number of neutrophils in a sample of blood.
Prevention
Precise diagnosis with a clear understanding of mechanisms responsible for the neutropenia is critical for providing specific treatment. In most cases, severe neutropenia is associated with the significant loss of CD4+ cells and an increase in viral load in patients infected with HIV.
Complications
Neutropenia is common after receiving chemotherapy and increases your risk for infections. Why Does Chemotherapy Cause Neutropenia? These cancer-fighting drugs work by killing fast-growing cells in the body—both good and bad.
What infections can cause neutropenia?
What is neutropenia and why is it important?
Why is diagnosis of severe neutropenia important in HIV infection?
What is neutropenia and why does chemotherapy cause it?
Can a virus cause low neutrophils?
A temporary decrease in the number of white blood cells in the bone marrow. An increase in the number of white blood cells being destroyed after a viral infection. It can take a lot of white blood cells to fight a viral infection. The level of neutrophils can fall quite low and may stay low for many months.
Why there is leukopenia in viral infection?
A person with leukopenia has a low number of white blood cells, or leukocytes, in their blood. White blood cells help fight infection in the body. A person with a low white blood cell count is more likely to contract an infection. Leukopenia usually involves a lack of neutrophils, which are a type of white blood cell.
Why does Covid cause neutropenia?
Neutropenia following COVID-19 infection may be due to the significant inflammatory response caused by the viral infection causing bone marrow suppression.
What happens to the number of neutrophils during a viral infection?
During a respiratory viral infection, neutrophils are recruited to and activated in the lung. In non-symptomatic or mild disease, neutrophil numbers peak early during infection and neutrophils exert their effector functions and aid in tissue repair and resolution of inflammation.
Do viral infections affect white blood cell count?
When you get sick, your body makes more white blood cells to fight the bacteria, viruses, or other foreign substances causing your illness. This increases your white blood count. Other diseases can cause your body to make fewer white blood cells than you need.
Which WBC is elevated in viral infection?
Neutrophils are infection fighters that increase during bacterial infections (neutrophils are also known as granulocytes (grans), polys, PMNs, or segs). Lymphocytes, on the other hand, can increase in cases of viral infections.
Can Covid cause severe neutropenia?
Low nadirs of lymphocyte and monocyte counts, as well as high peaks of absolute neutrophil counts, have been reported in severe cases of COVID‐19 that require admission of patients to the intensive care unit. 1 , 2 , 10 , 11 Neutrophilia predicts poor outcomes in patients with COVID‐19 and severe respiratory failure.
Does Covid cause low absolute neutrophils?
Another study reported lower granularity of neutrophils from COVID-19 patients that might explain the lower density (67). Detailed analysis of LDN partially reflected the transcriptional heterogeneity observed in whole blood neutrophil samples with distinct pro-, pre- and mature neutrophil clusters.
Does Covid cause low neutrophils?
COVID-19 infection causes a reduction in neutrophil counts in patients taking clozapine. Corresponding author. Received 2020 Nov 12; Revised 2020 Dec 2; Accepted 2020 Dec 2.
Are neutrophils important in viral infection?
Neutrophils are the first immune cell population recruited to sites of infection, including viral infections, and exhibit both protective and pathologic functions. In antibacterial and antifungal immunity, the role of neutrophils is well defined.
Does viral infection cause neutrophilia?
Although viral infections generally do not cause neutrophilia, it can occur during the early phases of infection (see below under "lymphocytosis").
Can a virus cause low white blood cell count?
One of the most common causes of a low white blood cell count is a viral infection. These infections can sometimes temporarily disrupt the bone marrow's production of blood cells, so blood cell counts drop. The counts typically rebound as the body recovers from the infection.
What is the cause of neutropenia?
Neutropenia Causes. Neutropenia Treatment. People with neutropenia have an unusually low number of cells called neutrophils. Neutrophils are cells in your immune system that attack bacteria and other organisms when they invade your body. Neutrophils are a type of white blood cell. Your bone marrow creates these cells.
Why does neutropenia go down?
Duration of severe neutropenia gets longer. Neutropenia Causes. The causes of neutropenia include: Problem in the production of neutrophils in the bone marrow. Destruction of neutrophils outside the bone marrow. Infection.
What causes a decrease in neutrophils?
Causes of decreased production of neutrophils include: Being born with a problem with bone marrow production (congenital) Leukemia and other conditions that affect the bone marrow or lead to bone marrow failure. Radiation. Chemotherapy. Infections that can cause neutropenia include: Tuberculosis. Dengue fever.
Why do neutrophils destroy?
Increased destruction of neutrophils can be due to the body's immune system targeting neutrophils for destruction. This may be related to having an autoimmune condition, such as: Crohn's disease. Rheumatoid arthritis.
Is a neutropenic fever a symptom of infection?
Fever is also a common symptom of infection. In a neutropenic fever, it is common not to identify the exact cause, which is often normal gut bacteria that has made its way into the blood from weakened barriers. Neutropenic fevers are usually treated with antibiotics, even if an infectious source can't be identified.
Where do infections occur in the body?
Infections can occur as a complication of neutropenia. They occur most often in the mucous membranes, such as the inside of the mouth and the skin. These infections can appear as: Ulcers. Abscesses (collections of pus) Rashes. Wounds that take a long time to heal.
Can Lupus cause neutropenia?
Lupus. In some people, neutropenia can be caused by certain medications, such as: Antibiotics. Blood pressure drugs. Psychiatric drugs. Epilepsy drugs. Neutropenia Treatment. When deciding on treatment, health care providers consider the cause and severity of the neutropenia. Mild cases may not need any treatment.
Which viruses are responsible for neutropenia?
The viruses responsible are chiefly the herpesviruses, both primary infections and reactivation, although other viruses are assuming recognized importance in this setting. This article provides a review of the infections that are encountered during the period of neutropenia in immunocompromised patients and the options available for ...
What is viral infection?
Viral infections are predominantly associated with defects in cellular immune function and might not be expected to cause problems in patients whose primary disease is accompanied by neutropenia.
What is neutropenia in blood?
What is neutropenia? Neutropenia refers to lower-than-normal levels of neutrophils in the blood. A neutrophil is a type of white blood cell that is produced mainly in the bone marrow. White blood cells in general, and neutrophils in particular, are important for infection control in the body.
How to prevent neutropenia?
These suggestions should help: Wash your hands frequently with soap and water. Wash your hands before and after you eat, after you use the toilet, after touching pets or things outside of your house, and after you cough or sneeze.
What is the lowest neutrophil count?
By many standards, the lowest acceptable limit for adults is about 1,500 neutrophils per microliter of blood. (Some put the cut-off at 1,800 per microliter.) The range of neutrophil numbers in mild neutropenia is 1,000-1,500; the number in moderate neutropenia is 500-1,000; and the count in severe neutropenia is less than 500.
What are the symptoms of neutropenia?
Neutropenia, especially in its mild form, may not have symptoms. If symptoms exist, they could include: 1 Fever 2 Sores 3 Swelling 4 Repeated infections
Can you die from febrile neutropenia?
Not treating febrile neutropenia could result in death. If neutropenia is caused by medication, your doctor might tell you to stop the medication. If the cause is an underlying disease, that condition must be treated (as in the case of a vitamin deficiency).
Can you get neutropenia from chemotherapy?
It sometimes results from an infection, but it is also often a result of treatment for cancer. It is estimated that 50 percent of the people who get chemotherapy will develop neutropenia.
Can you get febrile neutropenia without treatment?
Some types of neutropenia might require no treatment. However, in the case of neutropenia with fever (febrile neutropenia), treatment is necessary. Your doctor will prescribe drugs to fight the infection, such as antibiotics. If you do develop febrile neutropenia, your doctor is likely to admit you to the hospital.
Causes
Numerous factors may cause neutropenia through destruction, decreased production or abnormal storage of neutrophils.
Cancer and cancer treatments
Cancer chemotherapy is a common cause of neutropenia. In addition to killing cancer cells, chemotherapy can also destroy neutrophils and other healthy cells.
How long does it take for neutropenia to occur after chemo?
Neutropenia often occurs between 7 and 12 days after you receive chemotherapy. This period can be different depending upon the chemotherapy you get. Your doctor or nurse will let you know exactly when your white blood cell count is likely to be at its lowest. You should carefully watch for signs and symptoms of infection during this time.
What is the name of the decrease in white blood cells?
Neutropenia, pronounced noo-troh-PEE-nee-uh, is a decrease in the number of white blood cells. These cells are the body’s main defense against infection. Neutropenia is common after receiving chemotherapy and increases your risk for infections.
Abstract
Neutropenia frequently occurs in patients with Human immunodeficiency virus (HIV) infection.
INTRODUCTION
Human immunodeficiency virus (HIV) infection causes abnormality of CD4+ T cell function and loss of these immune effector cells through direct and indirect cytotoxicities of the virus.
CURRENT STATUS OF TREATMENT
Since multiple factors can cause neutropenia during HIV infection, treatment of this health problem relies on identifying the cause (s) as well as delineating the underlying mechanism (s). Specific management may vary from case to case, depending on the etiology and severity of neutropenia.
CONCLUSION
Neutropenia and myelosuppression frequently occur in individuals infected with HIV. Transient and moderate reduction of blood neutrophils in asymptomatic patients with HIV infection may not need specific medical intervention.
Acknowledgments
The authors thank Dr. H. Joe Wang at the National Institute of Alcohol Abuse and Alcoholism for his critical reading of the manuscript. We also thank Dr. Louaine Spriggs for her editorial assistance.
Footnotes
The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the article.
Which virus activates neutrophils?
Marburg and Ebola viruses were found to activate neutrophils via the triggering receptor expressed on myeloid cells (TREM)-1 [ 14 ]. Also, the soluble form of Ebola virus glycoprotein was shown to impair neutrophil activation via its binding to neutrophil CD16b and the inhibition of CD62L shedding [ 15 ].
What is the role of neutrophils in antiviral immunity?
Neutrophils are the first immune cell population recruited to sites of infection, including viral infections, and exhibit both protective and pathologic functions. In antibacterial and antifungal immunity, the role of neutrophils is well defined. However, in antiviral immunity, much less is known. Conventional wisdom suggests ...
What are the benefits of neutrophils?
Beneficial effects of neutrophils in viral infections. The role of neutrophils has been mostly studied in the context of IAV infection, a human respiratory virus that causes severe disease and high rates of mortality, especially among the elderly and the very young.
How do neutrophils protect against infection?
It is becoming apparent that the various mechanisms used by neutrophil antiviral defenses for protection against infections can also mediate direct tissue injury and disease, especially during prolonged or excessive responses. Through the production of proinflammatory cytokines such as TNF and IL-1 and the release of toxic substances such as hydrolytic enzymes, myeloperoxidase, and ROS, neutrophils can cause extracellular matrix damage, extensive cell death, and tissue necrosis. Through the secretion of cathepsin G, neutrophil elastase, and proteinase 3, they can promote additional vascular leakage, inflammation, and pathologic effects. Finally, through the deposition of NETs, they can trigger antibody-mediated autoimmune responses, additional damage of the local tissue, and eventual organ dysfunction. The key protective and damaging effects of neutrophil antiviral defenses are schematically summarized in Fig. 1 .
What are the effects of neutrophils on the host?
Although beneficial for antiviral immunity, the improper and/or prolonged activation of neutrophils can lead to detrimental effects to the host and can even cause severe disease, including pneumonia and acute respiratory distress syndrome [ 17, 18 ]. Neutrophils recruited to the lungs of infected animals produce proinflammatory mediators and toxic substances (e.g., cytokines, defensins, peroxidases, hydrolytic enzymes, and ROS) that can induce pathologic features. For example, IL-1 receptor-associated kinase-M deficiency, an inhibitor of MyD88-dependent TLR signaling, exacerbated the neutrophil influx in the lungs of IAV-infected mice and increased expression of inflammatory cytokines/chemokines and the subsequent lethality of the experimental mice [ 19 ]. Along this line, limiting neutrophil infiltration by an antibody against CXCR2 was beneficial to the host [ 19 ]. Accordingly, in an infection model of the mouse-adapted IAV A/PR/8/34 strain, the neutrophil counts in the bronchoalveolar lavage fluid had the same kinetics as MIP-2/CXCL2 production, and subsequent MIP-2/CXCL2 neutralization led to reduced infiltration of neutrophils, reduced pathologic features, and reduced lethality [ 20 ]. More recently, the analysis of a large amount of transcriptomic data using a systems biology approach suggested that influenza lethality is not associated with the pathogen's cytopathic action but rather with the inflammatory response orchestrated by the host [ 21 ]. It was demonstrated that lethal influenza infection in mice correlated better with excessive neutrophil activation than with the viral load and was linked to the presence of a proinflammatory transcriptional signature comprising TNF, IL-1, IL-6, and acute phase response genes and NF-κB, JAK-STAT, and MAPK signaling cascades [ 21 ]. In addition, severe disease caused by a recombinant IAV bearing the 1918 pandemic flu HA was accompanied by production of chemoattractants such as MIP-2/CXCL2 that resulted in increased recruitment of neutrophils in the lung and augmented intra-alveolar hemorrhage [ 22 ].
What is the role of neutrophils in the immune system?
Neutrophils belong to the first line of immune defense. They have a primary role in combating pathogen invasion, and they do so mainly by ingesting microorganisms and dying cells. Together with macrophages, they constitute the professional phagocytes, and they exhibit potent phagocytic properties similar to those of macrophages. Phagocytosed pathogens are destroyed intracellularly by a plethora of preformed mediators stored in neutrophilic granules such as antimicrobial peptides, proteolytic enzymes, and ROS generated via the action of NADPH oxidase [ 35 ]. Neutrophil phagocytosis is triggered by antibody- or complement-opsonized particles, although direct recognition of pathogens is also mediated by PRRs such as TLRs. The process of opsonization is well documented for bacterial pathogens and fungi. However, for viral infections, the ability of neutrophils to take up viral particles and kill them has been controversial.
What are the mechanisms by which neutrophils can contribute to pathogen clearance?
Interaction with other immune cell populations, virus internalization and killing, the release of cytokines, chemokines, and antimicrobial components are all mechanisms by which neutrophils can contribute to pathogen clearance.
