Etiology of Neutropenia and frequency of infection in children detected with neutropenia at a Pediatric Hematology Oncology Clinic

Neutropenia is defined as a neutrophil count below the expected value for age by -2 SDS, a common condition in childhood. The causes of neutropenia are numerous and diverse, including infections, medications, autoimmune causes, benign neutropenias, malignancies, and congenital neutropenias. The paucity of research on the etiology of neutropenia, coupled with the absence of consensus on the optimal management of neutropenia, can result in delays or unnecessary prolongation of the follow-up and treatment of patients diagnosed with neutropenia. The objective of our cross-sectional study is to ascertain the aetiology, follow-up periods, and infection frequencies of neutropenic patients. Introduction and Methods: The study was a cross-sectional study, and patients who had been followed up with neutropenia at the Pediatric Hematology and Oncology Clinic over a two-year period from June 2019 to June 2021 were included. A total of 232 patients were included in the study, with an absolute neutrophil count below 1000/mm3 for patients aged one month to one year and below 1500/mm3 for patients aged 1 to 18 years. All patients included in the study were evaluated retrospectively. Results: Of the 232 patients included in the study, 126 (54.3%) were male and 106 (45.7%) were female. Upon evaluation of the etiologies of the patients, 110 cases (47.4%) were identified as post-infectious neutropenia, 46 cases (19.8%) as malignancy, 31 cases (13.4%) as chronic idiopathic neutropenia, and seven cases (3%) as other causes. Congenital neutropenia was identified in six cases (2.6%), drug-related neutropenia in six cases (2.6%), immunodeficiency-related neutropenia in six cases (2.6%), nutrition-related neutropenia in six cases (2.6%), and 20 cases (8.6%) were attributed to other causes. Hospitalisation and antibiotic usage requirements were significantly lower in patients with post-infectious neutropenia, while they were significantly higher in congenital neutropenia and immunodeficiency-related neutropenia (p < 0.01). Conclusion: Our study found that infections were the most common cause of neutropenia, in line with the existing literature. Neutropenia is a significant issue for physicians due to its high prevalence and the numerous potential causes. While there is no consensus on the optimal management of neutropenia, there are a limited number of studies investigating the etiology of neutropenia. It is of great importance to both patients and their families that the causes of neutropenia are well understood, and that neutropenic patients are recognised. This is because it allows for the concerns of patients and their families to be reduced, and also because it allows for the costs of unnecessary tests to be avoided. Therefore, further studies are required in order to determine the etiology of neutropenia and to reach a consensus on the management of neutropenia.