Çocukluk çağında nötropenik hastaya yaklaşım

Nötrofiller konak savunmasında ve akut enflamasyonda önemli role sahiptir. Nötrofil sayısı azaldığında enfeksiyonlara eğilimin arttığı iyi bilinmektedir. Nötropeniler nötrofil sayısına göre hafif, orta ve ağır; nötropeni süresine göre akut ve kronik; oluşum mekanizmasına göre de kazanılmış ve doğuştan olarak sınıflanmaktadır. Nötropenik hastaların kliniği birbirinden farklıdır, altta yatan nedene bağlı olarak yaşamı tehdit eden enfeksiyonlar görülebilir ya da enfeksiyon hiç geçirmeyebilirler. Kazanılmış nötropeninin en sık nedeni viral enfeksiyonlar olup, bunu ilaçlar ve otoimmun nötropeniler izlemektedir. Doğuştan nötropenilere genellikle akut ve yaşamı tehdit edici invaziv bakteriyel ve fungal enfeksiyonların görülmesi ile tanı koyulur. Doğuştan nötropenide immün sistem bozuklukları ve diğer sistem bulguları eşlik edebilir veya etmeyebilir. Son yıllarda, genetik tanı tekniklerinin gelişmesiyle doğuştan nötropeniye neden olan birçok yeni tek gen defekti tanımlanmıştır. Moleküler tanı; risk sınıflaması, tedavi seçimi ve hastalığın seyrini belirlemede yararlıdır. Bu derleme, çocuk hekimleri için nötropenik hastaya yaklaşım, nötropenide hangi testler yapılmalı ve ne zaman kan hastalıkları uzmanına yönlendirilmeli konularında bir rehber niteliğinde hazırlanmıştır

Approach to the patient with neutropenia in childhood

Neutrophils have an important role in host defense and acute inflammation. It is well known that susceptibility to infection increases when the neutrophil count is low. Neutropenia were classified as mild, moderate and severe according to the neutrophil counts, or acute and chronic depending on the duration of neutropenia, or congenital and acquired according to the mechanism. The patients with neutropenia are clinically different due to underlying mechanism, they have life- threatening infections or no infection may be observed. The most common cause of acquired neutropenia is viral infection, followed by drugs and autoimmune neutropenia. Congenital neutropenia are usually diagnosed by acute and life- threatening invasive bacterial and fungal infections. Immune system disorders and other systemic abnormalities may be accompanied or not. Recent years, novel single gen defects causing congenital neutropenia were defined through advanced genetic techniques. Molecular diagnosis is useful for risk stratification, choice of therapy and prognosis on followup. This review was prepared for pediatricians as a guide focused on approach neutropenia, which tests should be performed and when should be referred to a specialist

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