Autoimmune neutropenia in children: analysis of 116 cases

Abstract

Diagnosis of autoimmune neutropenia (AIN) in infants is important, because it allows the exclusion of more severe forms of neutropenia that have an increased risk for leukemia. AIN is characterized by chronic neutropenia, which spontaneously resolves within several months to a few years, and mild infections. Diagnosis is confirmed by the presence of antibodies directed against neutrophil antigens. The human neutrophil antigen (HNA) system is a polymorphic system, which includes five antigen groups with different polymorphisms. In AIN, antibodies are mostly directed against HNA-1 (or against a specific allele of HNA-1) and HNA-4. Here, we present a series of 116 infants with AIN. We observed that anti-neutrophil antibodies were present in 60% cases; directed against HNA-1a in 73% of cases. In addition, we showed there was a bias in the HNA allele distribution in these infants because the frequency of the HNA-1a allele was greater in comparison with controls.

Infectious Complications In Children With Severe Congenital, Autoimmune Or Idiopathic Neutropenia

“…this may be due to a stricter infection definition applied in the present study. 3,5 skin and subcutaneous tissues were the most common sites regardless of the type of neutropenia, and accounted for greater than half the cases of infections. this is in agreement with the fact that skin/subcutaneous lesions are events often leading to diagnosis because they tend to recur and to be difficult to eradicate.…”

“…4 Although pathogenesis of K. kingae invasive infections remains unclear, there is evidence that K. kingae first colonizes the oropharynx before penetrating the bloodstream and invading distant organs. 5 previous studies suggested that respiratory carriage of K. kingae is a prerequisite for distant infection of joint and bone. [6][7][8] the oropharyngeal carriage of K. kingae does not necessary imply the subsequent development of an invasive infection, and the probability for asymptomatic children carrying K. kingae to develop an osteoarticular infection is lower than 1%.…”

“…in severe congenital neutropenia (sCN), sepsis is a potential cause of death with a cumulative risk assessed at 15% after 20 years of observation, 1,2 despite granulocyte-colony stimulating factor therapy (G-Csf). Conversely, autoimmune neutropenia (AN) and idiopathic neutropenia (iN) patients are reported to have milder infections [3][4][5][6] and sometimes their early occurrence or occurrence in unusual sites (skin, mouth, perianal region) can lead to the diagnosis of neutropenia. 1 epidemiology of infections and detailed description of type and site of infections in both congenital and acquired neutropenia are lacking.…”

Diagnosis and management of primary autoimmune neutropenia in children: insights for clinicians

“…The historical incidence is reported to be 1 out of 100,000 children under 10 years of age [Lyall et al 1992] but, due to the benign course of the disease, there is clear evidence of underreporting, highlighted by frequent fortuitous findings (8-27% of all cases) [Bux et al 1998;Audrain et al 2011]. In our experience, diagnosis as consequence of a blood count planned for other reasons (i.e.…”

Chronic Neutropenia in Childhood

“…The detection of these antibodies is technically difficult; thus they are not always evaluated in clinical practise. 19,20 The etiology of neutropenia is most often autoimmune or idiopathic. 4,6,10 CIN was found to be caused by one of these etiologies in a similar proportion of our patients (34.0% to 68.9%) compared with previously studied cohorts.…”