Cytomegalovirus induced hemophagocytic lymphocytic histiocytosis in two pediatric patients with acute lymphoblastic leukemia

Abstract

Hemophagocytic lymphohistiocytosis (HLH) is a rare inflammatory condition with tissue destruction due to abnormal immune activation. We present a series of 2 cases of cytomegalovirus-induced HLH in children during maintenance chemotherapy for acute lymphoblastic leukemia. These cases emphasize the importance of considering secondary HLH in this high-risk subset of pediatric patients.

Systemic viral infection in children receiving chemotherapy for acute leukemia

“…Symptomatic CMV infection was reported in 28 patients (19 boys, 9 girls; median age 8.5 years, range, 1‐15 years; Table 1). 10‐30 All but one patient suffered from ALL, and one patient had relapsed AML. The infection occurred in most of the patients ( n = 22) during maintenance therapy, and main symptoms were persisting fever not to be explained by other causes (19 patients), visual disturbances (10 patients), acute visual loss (one patient) or retinitis (two patients), pancytopenia (six patients) or hepatomegaly (eight patients).…”

Six-Year Long Follow-up of Patient With Wiskott-Aldrich Syndrome Post Haploidentical Stem Cell Transplant

“…There is evidence to suggest impairment in NK-cell activity leads to persistent activation of macrophages and production of cytokines. 3 Secondary HLH can occur with malignancy, infection, autoimmune/ inflammatory disorders, or metabolic diseases. 4 Infections, especially viral, have been associated with reduced NK-cell quantities, underlying the basis for viralassociated HLH syndromes.…”

“…4 Infections, especially viral, have been associated with reduced NK-cell quantities, underlying the basis for viralassociated HLH syndromes. 3 The underlying immunodeficient state because of the malignancy, combined with chemotherapy, may both predispose to infection and contribute to defects in T-cell and NK-cell function, leading to a dysregulated immune response to the infectious trigger. 4 Therefore, infections such as CMV should be screened and treated well in the immunosuppressed patient.…”

“…The outcomes of HSCT with PTCy in children with nonmalignant diseases have been comparable with other donor type. 2,3 This establishes that haplo-HSCT with PTCy is a feasible and successful curative option for patients with WAS who do not have a full match donor available. With addition of our case to the series, this makes our patient the 14th reported case of WAS in the literature who has undergone haplo-HSCT with PTCy with the longest follow-up.…”

Cytomegalovirus-related Hemophagocytosis in Childhood Acute Lymphoblastic Leukemia

“…The pathogenesis of HLH is not well understood. There is evidence to suggest impairment in NK-cell activity leads to persistent activation of macrophages and production of cytokines 3. Secondary HLH can occur with malignancy, infection, autoimmune/inflammatory disorders, or metabolic diseases 4.…”