UNC13D mutations in Egyptian children with hemophagocytic lymphohistiocytosis

Abstract Background Familial hemophagocytic lymphohistiocytosis (FHL) is invariably fatal without appropriate treatment. This study evaluated the frequency and types of UNC13D mutations in patients fulfilling HLH criteria and correlated them with disease severity. Forty suspected HLH patients underwent detailed medical history and clinical examination. Complete blood count, liver enzymes, total and direct bilirubin, serum ferritin, serum fibrinogen, serum triglycerides, soluble CD25, bone marrow aspirate, brain MRI, CSF analysis, and genetic testing were performed. Results Forty patients were recruited with mean age of 34 months at diagnosis. Twenty-five (62.5%) patients had mutations for FHL, 10 of them had UNC13D mutations which represented the second most common gene mutation in our cohort. Missense mutation c.902 A>G was the most prevalent ( n = 4, 40%) detected mutation in UNC13D group. There was no significant difference between patients with UNC13D mutations and other patients as regards clinical, laboratory, radiological findings or outcome except that all patients with UNC13D mutations admitted to ICU were due to disease rather than sepsis ( p < 0.001). Conclusion UNC13D mutations is the second most common FHL among Egyptian children with clinical features comparable to other subtypes, highlighting the need for larger multicenter studies to better define genotype-phenotype correlations.