From the Guidelines
A neutrophil count of 0.2 × 10^9/L is severely low and represents a dangerous condition called severe neutropenia that requires immediate medical attention. You should go to the emergency room right away as this level puts you at extremely high risk for serious infections that could be life-threatening. Normal neutrophil counts range from 1.5-8.0 × 10^9/L, and counts below 0.5 are considered severe neutropenia [ 1 ]. At this level, your body cannot effectively fight bacterial infections, and even normally harmless bacteria from your skin or gut can cause serious illness.
Causes and Risks
The causes of neutropenia at this level can include chemotherapy, certain medications, autoimmune disorders, or bone marrow diseases [ 1 ]. The risk of infection is inversely proportional to the neutrophil count, and the rate of decline of the neutrophil count and the duration of neutropenia are critical factors in determining the severity of infection and clinical outcome [ 1 ].
Management and Treatment
Your doctor will likely admit you to the hospital, perform tests to determine the cause, and may start prophylactic antibiotics such as levofloxacin or ciprofloxxin [ 1 ]. They might also prescribe granulocyte colony-stimulating factor (G-CSF) medications like filgrastim to stimulate neutrophil production. While waiting for medical care, avoid crowds, practice excellent hygiene, and watch for fever, which would be a medical emergency requiring immediate antibiotics [ 1 ].
Key Considerations
It is essential to note that patients with persistent fever despite neutrophil recovery should be assessed by an ID physician or clinical microbiologist, and antifungal therapy considered [ 1 ]. The management of febrile neutropenia should be guided by clinical practice guidelines, which recommend risk-stratifying patients according to susceptibility to infection [ 1 ].
Next Steps
Given the severity of the condition, it is crucial to seek immediate medical attention to prevent serious complications and improve outcomes. The hospital team will work to determine the underlying cause of the neutropenia and develop an appropriate treatment plan to manage the condition and prevent further complications [ 1 ].
From the FDA Drug Label
The main efficacy endpoint was the incidence of febrile neutropenia. Febrile neutropenia was defined as an ANC < 1,000/mm3 and temperature > 38.2°C. Treatment with filgrastim resulted in a clinically and statistically significant reduction in the incidence of infection‚ as manifested by febrile neutropenia, 40% for filgrastim-treated patients and 76% for placebo-treated patients (p < 0. 001). The main efficacy endpoint was median duration of severe neutropenia defined as neutrophil count < 500/mm3 A statistically significant reduction in the median number of days of severe neutropenia (ANC < 500/mm3) occurred in the filgrastim-treated groups versus the control group
A neutrophil count of 0.2 is considered severe neutropenia, as it is significantly lower than the threshold of < 500/mm3 or < 1,000/mm3 mentioned in the studies 2. This condition increases the risk of infection and febrile neutropenia.
From the Research
Neutrophil Count Interpretation
- A neutrophil count of 0.2 is considered severe neutropenia, as it falls below the threshold of 500 cells/mm^3 3.
- Severe neutropenia is associated with a high risk of infection, and the risk is directly proportional to the severity and duration of neutropenia 3.
Clinical Significance of Neutropenia
- Neutropenia can be caused by various factors, including decreased bone marrow production, sequestration of neutrophils, and increased destruction of neutrophils in the peripheral blood 3.
- The clinical significance of neutropenia depends on the underlying cause and the severity of the condition, with severe neutropenia being associated with a higher risk of mortality 4, 5.
- A study found that an absolute neutrophil count of 0.5 x 10^9/L was associated with a high mortality rate, highlighting the importance of careful evaluation and management of neutropenia 4.
Comparison with Other Conditions
- Neutropenia is associated with various diseases, including viral infections, hematological malignancies, and autoimmune disorders 5.
- The risk of hematological malignancies and mortality increases with decreasing absolute neutrophil count, with severe neutropenia being associated with a high risk of these conditions 5.
- A study comparing the risk of neutropenia associated with piperacillin-tazobactam and cefazolin found that the risk was similar between the two antibiotics, but the results require confirmation in a larger clinical trial 6.