A case of hemophagocytic lymphohistiocytosis in a patient with chronic lymphocytic leukemia after treatment with fludarabine, cyclophosphamide, and rituximab chemotherapy, with autopsy findings

Babesia microti-induced fulminant sepsis in an immunocompromised host: A case report and the case-specific literature review

Babesia microti is an obligate intra-erythrocytic parasite transmitted by infected ticks. B. microti is a eukaryote much larger than prokaryotic microbes and more similar to human hosts in their biochemistry and metabolism. Moreover, Babesia spp. possess various immune evasion mechanisms leading to persistent and sometimes life-threatening diseases in immunocompromised hosts. Chronic lymphocytic leukemia (CLL) is the most prevalent adult B-cell malignancy, and a small percentage of CLL transforms into aggressive lymphomas. CLL also causes immune dysfunction due to the over-expansion of immature and ineffective B-cells. When our patient with indolent CLL presented with anemia, pancytopenia, and splenomegaly, all his healthcare providers presumptively assumed a malignant transformation of CLL. However, these are also the signs and symptoms of babesiosis. Herein, we report a case where B. microti infection was presumed as a malignant transformation of CLL and narrowly avoided a devastating outcome. Although the patient developed fulminant sepsis, he finally received the correct diagnosis and treatment. Unfortunately, the disease recrudesced twice. Each time, it became more difficult to control the infection. We describe the clinical course of the case and discuss the case-specific literature review. This report highlights the importance of differential diagnoses ruling out infections which include babesiosis, prior to initiating the treatment of B-cell malignancy.

Standard-Dose Rituximab as Effective Therapy for Treating Malignancy-Related Hemophagocytic Lymphohistiocytosis in the Eldery: A Case Report

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome involving uncontrolled inflammation due to widespread activation of immune response. HLH can be inherited or acquired secondary to infection, autoimmune, or oncologic processes such as small lymphocytic lymphoma (SLL) or chronic lymphocytic leukemia (CLL). There has been minimal documentation of HLH secondary to SLL/CLL, and results of treatment have been largely unsuccessful. This case describes a critically ill elderly patient with HLH caused by SLL/CLL who was successfully treated with standard-dose rituximab and regained a high quality of life.

A systematic review of malignancy-associated hemophagocytic lymphohistiocytosis that needs more attentions

As an infrequent but potentially life-threatening hyperinflammatory syndrome, hemophagocytic lymphohistiocytosis (HLH) is clinically characterized with prolonged fever, hepatosplenomegaly, cytopenia, hypertriglyceridemia, hyperferritinemia and hemophagocytosis in bone marrow, liver, spleen or lymph nodes. Malignancy-associated HLH (M-HLH), one type of acquired HLH, usually presents variable overlaps of symptoms with other types of HLH, thus resulting in higher incidence of misdiagnosis and mortality. In recent years, with the increasing awareness to this disease, the diagnosis and management of HLH have gained more and more attention, and improvements have been made accordingly. As a result, the survival of patients is greatly prolonged. However, there is still no consensus on the diagnostic criteria and treatment strategies due to lack of large samples or prospective clinical trials. In order to improve recognition and diagnosis, and provide guidance regarding the treatment of M-HLH, the Study Group in HLH Subtypes of the Histiocyte Society has developed consensus recommendations for the diagnosis and management of M-HLH in 2015. In the present article, we summarized and discussed some updated understandings in M-HLH.

Proliferation through activation: hemophagocytic lymphohistiocytosis in hematologic malignancy

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of cytokine-driven immune activation. Cardinal features include fever, hemophagocytosis, hepatosplenomegaly, lymphocytic infiltration, and hypercytokinemia that result in multisystem organ dysfunction and failure. Familial HLH is genetically driven, whereas secondary HLH (SHL) is caused by drugs, autoimmune disease, infection, or cancer. SHL is associated with worse outcomes, with a median overall survival typically of less than 1 year. This reflects difficulty in both diagnostic accuracy and in establishing reliable treatments, especially in cases of malignancy-induced SHL, which have significantly worse outcomes. Malignancy-induced HLH is seen almost exclusively with hematologic malignancies, constituting 97% of cases in the literature over the past 2 years. In these situations, the native immune response driven by CD8 T cells produces an overabundance of T helper 1 cytokines, notably interferon-γ, tumor necrosis factor-α, and interleukin-6, which establish a positive feedback loop of inflammation, enhancing replication of hematologic malignancies while leaving the host immune system in disarray. In this paper, we present 2 case studies of secondary HLH driven by HM, followed by a review of the literature discussing the cytokines driving HLH, diagnostic criteria, and current treatments used or undergoing investigation.

Haemophagocytic lymphohistiocytosis as a consequence of untreated B-cell chronic lymphocytic leukaemia

Haemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening syndrome characterised by defective cytotoxic function and hypercytokinaemia leading to macrophage expansion and haemophagocytosis. Patients often present with unexplained fevers, hepatosplenomegaly and pancytopenia, with elevation in serum ferritin and triglyceride. Acquired forms are triggered by infection, malignancy or rheumatological disorders. HLH in the setting of chronic lymphocytic leukaemia is rarely reported, however, and is usually associated with infection or as a consequence of chemotherapy. We present a case of HLH in a 64-year-old Caucasian woman with the only identified trigger being her hitherto untreated CLL.

Secondary Hemophagocytic Syndrome Associated with Richter's Transformation in Chronic Lymphocytic Leukemia

Hemophagocytic syndrome (HPS) is an extremely rare condition arising from the overactivation of one's own immune system. It results in excessive inflammation and tissue destruction. Prompt initiation of treatment is warranted in either scenario in order to decrease mortality. Most cases are triggered by infectious agents, malignancy, or drugs. We describe the first case of a CLL patient presenting with HPS due to acquisition of EBV-related large cell lymphoma in the setting of profound immunodeficiency.