Diagnosis of GATA2 Deficiency in a Young Woman with Hemophagocytic Lymphohistiocytosis Triggered by Acute Systemic Cytomegalovirus Infection

BACKGROUND Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disease characterized by an intense immunologic response that results in multiorgan dysfunction. It typically manifests as a result of a familial genetic immunodeficiency disorder or secondary to a trigger such as an infection, malignancy, or autoimmune disease. The major factors involved in the development of the disease are an individual's genetic propensity to develop HLH, such as rare associated mutations, or inflammatory processes that trigger the immune system to go haywire. CASE REPORT Before the COVID-19 pandemic, a 22-year-old woman with a history of congenital absence of the right kidney, right-sided hearing loss, and leukopenia presented with a 3-week history of generalized malaise, fever, chest pain, cough, and shortness of breath. She developed an acute systemic cytomegalovirus infection further complicated by HLH. Based on her history and clinical course, an underlying primary immunodeficiency was suspected. An immunodeficiency gene panel revealed a monoallelic mutation in GATA2, a gene that encodes zinc-transcription factors responsible for the regulation of hematopoiesis. CONCLUSIONS GATA2 deficiency encompasses a large variety of mutations in the GATA2 gene and leads to disorders associated with hematologic and immunologic manifestations of monocytopenia and B-, and natural killer-cell deficiency. Over time, affected individuals are at high risk of developing life-threatening infections and serious hematologic complications, such as myelodysplastic syndromes and/or leukemias. We aimed to illustrate the importance of identifying an underlying genetic disorder associated with secondary HLH to help guide acute and long-term management.