From the Guidelines
Cyclic neutropenia is a rare blood disorder characterized by periodic episodes of neutropenia, typically occurring every 21 days, lasting 3-6 days, and is effectively managed with granulocyte colony-stimulating factor (G-CSF) therapy, as established by a randomized controlled trial involving 123 patients 1.
Definition and Characteristics
Cyclic neutropenia is a condition where individuals experience recurrent episodes of neutropenia, which is a lower-than-normal count of neutrophils, a type of white blood cell important for fighting infections. This condition can lead to increased susceptibility to infections, particularly during the periods of neutropenia.
Treatment and Management
The primary treatment for cyclic neutropenia involves the use of G-CSF, which has been shown to be effective in normalizing neutrophil counts and preventing infections, as demonstrated in a study published in the Journal of the National Comprehensive Cancer Network 1. The dosage of G-CSF can vary, but it is typically administered subcutaneously at doses of 1-3 mcg/kg/d, with adjustments made based on the patient's response and to maintain a blood neutrophil level in the normal or low normal range.
Key Considerations
- Adjustment of G-CSF doses is crucial to minimize the risk of adverse effects, such as bone pain, arthralgias, and myalgias, which are common but usually diminish over the first few weeks of treatment 1.
- Regular monitoring of blood counts is essential to track neutrophil cycles and adjust treatment accordingly.
- Good hygiene practices and avoiding crowds during neutropenic periods can help reduce the risk of infections.
- Prompt medical attention should be sought for fevers above 100.4°F (38°C) to prevent complications.
Prognosis and Quality of Life
With proper management, including G-CSF therapy and preventive measures, most patients with cyclic neutropenia can lead normal lives with a good long-term prognosis, as the treatment effectively reduces the frequency and severity of infections 1.
From the FDA Drug Label
Patients eligible for Study 7 had a history of severe chronic neutropenia documented with an ANC < 500/mm3 on three occasions during a 6-month period, or in patients with cyclic neutropenia 5 consecutive days of ANC < 500/mm3 per cycle. Although filgrastim substantially reduced neutropenia in all patient groups‚ in patients with cyclic neutropenia‚ cycling persisted but the period of neutropenia was shortened to 1 day.
Cyclic Neutropenia is a condition characterized by periodic episodes of neutropenia, where the patient experiences recurring periods of low neutrophil count, typically lasting for a few days. In the context of this study, cyclic neutropenia was defined as 5 consecutive days of ANC < 500/mm3 per cycle 2.
From the Research
Definition and Characteristics of Cyclic Neutropenia
- Cyclic neutropenia is a rare hematological condition characterized by periodic fluctuations in neutrophil counts, with a 21-day periodicity 3.
- It is an inherited autosomal dominant disorder due to mutations in the gene for neutrophil elastase (ELA-2 or ELANE) 4.
- The condition is marked by regular oscillation of blood neutrophil counts with periods of severe neutropenia occurring every 21 days 4.
- During these periods, patients experience painful mouth ulcers, fevers, and bacterial infections 3, 5, 4.
Clinical Presentation and Symptoms
- Clinical presentation varies from mild to severe forms of the disease, with the onset of recurrent fever, painful oral ulcers, recurrent bacterial infections, peritonitis, and septic shock 3.
- Patients may also experience malaise, oral ulceration, and minor skin and upper respiratory tract infections 5.
- Severe dental disease is common, pregnancy complications are increased, and overwhelming infections, bowel necrosis, and mortality, although rare, are potential sequelae 5.
Treatment and Management
- The availability of granulocyte colony-stimulating factor (G-CSF) has revolutionized the management and natural history of this disease, regulating the proliferation, differentiation, and maturation of the progenitor cells, and reducing the duration of neutropenia 3.
- G-CSF therapy has been shown to be effective in increasing neutrophil counts, reducing the frequency of infections, and improving quality of life 6, 5, 7.
- Treatment with G-CSF is usually effective, but the dose required to normalize blood neutrophils varies greatly 4.