What nephrologists need to know about hemophagocytic syndrome. Nat Rev Nephrol. 2009;5:329-336. [PMID: 19424103 DOI: 10.1038/nrneph.2009.73]

Acute kidney injury in critical care: complications of hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is an immune dysfunction characterized by an exaggerated and pathological inflammatory response, potentially leading to systemic inflammatory reactions and multiple-organ failure, including renal involvement. HLH can be classified as primary or secondary, with primary HLH associated with genetic mutations affecting cell degranulation capacity, and secondary HLH often linked to infections, tumors, and autoimmune diseases. The pathogenesis of HLH is not fully understood, but primary HLH is typically driven by genetic defects, whereas secondary HLH involves the activation of CD8+ T cells and macrophages, leading to the release of inflammatory cytokines and systemic inflammatory response syndrome (SIRS). The clinical presentation of HLH includes non-specific manifestations, making it challenging to differentiate from severe sepsis, particularly secondary HLH due to infections. Shared features include prolonged fever, hepatosplenomegaly, hematopenia, hepatic dysfunction, hypertriglyceridemia, and hypofibrinogenemia, along with histiocytosis and hemophagocytosis. However, distinctive markers like dual hemocytopenia, hypertriglyceridemia, hypofibrinogenemia, and elevated sCD25 levels may aid in differentiating HLH from sepsis. Indeed, no singular biomarker effectively distinguishes between hemophagocytic lymphohistiocytosis and infection. However, research on combined biomarkers provides insights into the differential diagnosis. Renal impairment is frequently encountered in both HLH and sepsis. It can result from a systemic inflammatory response triggered by an influx of inflammatory mediators, from direct damage caused by these factors, or as a consequence of the primary disease process. For instance, macrophage infiltration of the kidney can lead to structural damage affecting various renal components, precipitating disease. Presently, tubular necrosis remains the predominant form of renal involvement in HLH-associated acute kidney injury (HLH-AKI). However, histopathological changes may also encompass interstitial inflammation, glomerular abnormalities, microscopic lesions, and thrombotic microangiopathy. Treatment approaches for HLH and sepsis diverge significantly. HLH is primarily managed with repeated chemotherapy to eliminate immune-activating stimuli and suppress hypercellularity. The treatment approach for sepsis primarily focuses on anti-infective therapy and intensive symptomatic supportive care. Renal function significantly influences clinical decision-making, particularly regarding the selection of chemotherapy and antibiotic dosages, which can profoundly impact patient prognosis. Conversely, renal function recovery is a complex process influenced by factors such as disease severity, timely diagnosis, and the intensity of treatment. A crucial aspect in managing HLH-AKI is the timely diagnosis, which plays a pivotal role in reversing renal impairment and creating a therapeutic window for intervention, may have opportunity to improve patient prognosis. Understanding the clinical characteristics, underlying causes, biomarkers, immunopathogenesis, and treatment options for hemophagocytic lymphohistiocytosis associated with acute kidney injury (HLH-AKI) is crucial for improving patient prognosis.

Concept and Diagnostic Challenges of Renal-Limited Hemophagocytic Syndrome/Macrophage Activation Syndrome

Hemophagocytic syndrome/macrophage activation syndrome (HPS/MAS) is a serious clinical condition that frequently leads to multiple organ failure, including acute kidney injury (AKI). Although the pathogenesis of AKI is not yet fully understood, it is believed to result from uncontrolled activation of the immune system involving macrophages and cytotoxic lymphocytes. Renal histology in HPS/MAS often presents with characteristic foamy glomerular lesions (glomerular lipidosis) with massive macrophage infiltration, known as histiocytic glomerulopathy. In this review, we introduce the recently proposed concept of renal-limited HPS/MAS as a novel etiology of histiocytic glomerular lipidosis. Patients with renal-limited HPS/MAS often develop AKI but do not fulfill the diagnostic criteria for HPS/MAS because their systemic manifestations are less severe. Therefore, the diagnosis largely depends on characteristic histological findings, that is, diffuse and global glomerular accumulation of foamy macrophages and cytotoxic lymphocytes accompanied by the interaction of these cells as well as the exclusion of various differential diseases. Although there are no established therapeutic regimens, these patients receive various types of therapies, including high-dose glucocorticoids, immunosuppressants, or anti-interleukin-1 drug, and generally achieve favorable outcomes. We summarized the concept, diagnostic challenges, and recent topics of this disease entity and discussed treatment options based on our own experiences.

Hemophagocytic lymphohistiocytosis after solid organ transplantation: A challenge for clinicians

Hemophagocytic lymphohistiocytosis (HLH) is a rare inflammatory disorder with a high mortality rate and a wide range of symptoms. Solid organ transplantation, which provides patients with a unique immunosuppressive state, is a less common predisposing factor for HLH. HLH after solid organ transplantation (HLH-SOT) is very rare and fatal. It is hard to diagnose and treat and extremely understudied. The use of immunosuppressants makes the situation of HLH-SOT more complex. This review summarizes the existing literature on HLH after solid organ transplantation and describes its triggers and symptoms, focusing on its diagnosis and treatment. We performed a literature search of case reports, case series, letters to the editor, and clinical quizzes describing patients with HLH after solid organ transplantation (HLH-SOT). We provide recommendations on the diagnosis protocol and treatment strategy based on the existing evidence.

Case report of extranodal natural killer/T-cell lymphoma that induced secondary hemophagocytic syndrome-related histiocytic glomerulopathy

Hemophagocytic syndrome (HPS) is a proliferative disease of the mononuclear macrophage system involving multiple organs and systems. We report a 50-year-old Asian woman who presented with unexplained fever and proteinuria. Laboratory tests showed cytopenia, considerably elevated serum ferritin and IL-2 receptor concentrations, and evidence of hemophagocytosis in the bone marrow. A renal biopsy showed macrophage infiltration into the glomerulus, resulting in podocyte and endothelial cell damage. We finally diagnosed the patient with extranodal natural killer/T-cell lymphoma, nasal type that induced HPS-related histiocytic glomerulopathy. Proteinuria and inflammation responded to treatment with high-dose pulsed methylprednisolone combined with VP-16 and cyclosporine. To the best of our knowledge, this is the first documented case of HPS-related histiocytic glomerulopathy triggered by a malignant tumor.

Isolated massive histiocytes renal interstitial infiltration: a case report of an unexpected cause of acute kidney injury in a kidney transplant recipient

BACKGROUND

Acute kidney injury is a frequent cause of hospital readmission in kidney transplant recipients (KTR), usually associated with infections and graft rejection. Herein, we report a case of an unusual cause of acute kidney injury in a KTR (massive histiocytes renal interstitial infiltration).

CASE PRESENTATION

A 40-year-old woman was submitted to a second kidney transplant. One year after surgery, she presented asthenia, myalgia, and fever, haemoglobin 6.1 g/dL; neutrophils: 1.3 × 109/µL; platelets: 143 × 109/µL; blood creatinine 11.8 mg/dL, requiring dialysis. A kidney biopsy revealed diffuse histiocytic infiltration, which was assumed due to dysregulated immunological activation triggered by infections. The patient had multiple infections, including cytomegalovirus infection (CMV), aspergillosis, bacteraemia, and urinary tract infections, which could trigger the immune response. Haemophagocytic lymphohistiocytosis (HLH) was ruled out. The present case highlights the occurrence of isolated massive renal interstitial infiltration of histiocytes that does not meet the criteria for HLH or other related pathologies.

CONCLUSIONS

Renal histiocyte activation and infiltration may have been initiated by an immunological mechanism similar to what occurs in HLH and infectious processes. The present case highlights the occurrence of isolated massive renal interstitial infiltration of histiocytes that does not meet the criteria for HLH or other related pathologies.

Streptococcal Infection-related Glomerulonephritis in an Elderly Diabetic Patient Complicated by Hemophagocytic Syndrome and Cytomegalovirus Nephritis

There has been a significant shift in epidemiology and renal outcomes of infection-related glomerulonephritis (IRGN) in recent years. The renal prognosis of IRGN is often poor in adults, especially in the elderly and diabetics. We herein report an elderly diabetic patient with IRGN due to streptococcal infection complicated by hemophagocytic syndrome and cytomegalovirus nephritis, which is uncommon among non-transplant patients. Infection control and steroids did not recover the patient's renal function. For elderly IRGN patients with diabetes, a further investigation of the most effective treatment for related renal outcomes is needed.

Renal involvement as a unique manifestation of hemophagocytic syndrome

Renal-limited hemophagocytic syndrome (HPS) is a rare clinical setting characterized by abnormal activation of the immune system. Fever associated with pancytopenia, hepatosplenomegaly with liver dysfunction, and hypofibrinogenemia are usually observed in HPS. From a histological level, the presence of non-malignant macrophages infiltrating bone marrow and organs represents the hallmark of this condition. Non-malignant macrophages are associated with phagocytizing activities involving other blood cells. While primary HPS is usually associated with inherited dysregulation of the immune system, secondary HPS usually occurs in the context of infection or is linked to a neoplastic process. Clinical presentation varies and can potentially lead to life-threatening settings. While renal involvement has frequently been reported, however, detailed descriptions of the kidney manifestations of HPS are lacking. More critically, the diagnosis of HPS is rarely supported by renal biopsy specimens. We report four rare cases of biopsy-proven renal-limited HPS in patients presenting with acute kidney injury (AKI). The available evidence on this topic is critically discussed in light of the possible emergence of an autonomous entity characterized by an isolated kidney involvement.

Hematological Malignancies and the Kidney

The incidence of hematologic malignancies is on the rise worldwide. Kidney disease is ubiquitous in patients with hematologic malignancies, encompassing a wide spectrum of disorders involving each kidney compartment, including the vasculature, tubules, interstitium, and glomerulus, and there is significant overlap of kidney involvement with each hematologic malignancy. Vascular disorders include both microvascular and macrovascular damage, via thrombotic microangiopathy, hyperleukocytosis, hyperviscosity, and cryoglobulinemia. The tubulointerstitial compartment may be affected by prerenal azotemia and acute tubular injury, but malignant infiltration, tumor lysis syndrome, extramedullary hematopoiesis, cast nephropathy, granulomatous interstitial nephritis, and lysozymuria should be considered in certain populations. Obstructive uropathy may occur due to nephrolithiasis or retroperitoneal fibrosis. Glomerular disorders, including membranoproliferative, membranous, minimal change, and focal segmental glomerulosclerosis, can rarely occur. By understanding how each compartment may be affected, care can best be optimized for these patients. In this review, we summarize the widely varied etiologies of kidney diseases stratified by kidney compartment and hematologic malignancy, focusing on demographics, pathology, pathophysiology, mechanism, and outcomes. We conclude with common electrolyte abnormalities associated with hematologic malignancies.

Histiocytic Glomerulopathy Associated With Hemophagocytic Lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a systemic inflammatory syndrome characterized by heightened activation and proliferation of nonmalignant macrophages and excessive cytokine release. Whereas acute kidney injury is common in this syndrome, direct glomerular involvement by activated histiocytes is very rare. We present the case of a man in his 20s who presented with fevers, malaise, flank pain, anemia, thrombocytopenia, severe acute kidney injury, and proteinuria. A kidney biopsy revealed histiocytic glomerulopathy and subacute thrombotic microangiopathy, and he was diagnosed with HLH. Recovery of kidney function occurred following steroid therapy. A review of kidney involvement by HLH is provided.

Ruxolitinib is an alternative to etoposide for patient with hemophagocytic lymphohistiocytosis complicated by acute renal injury: A case report

INTRODUCTION

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening syndrome characterized by excessive production of inflammatory cytokines and multiple organs injury. Ruxolitinib, an oral selective JAK1/2 inhibitor, has recently shown efficacy and safety in the treatment of secondary HLH, which may be an alternative to intensive chemotherapy.

CASE REPORT

We report a case of a 2-year-old boy who presented to our institution with recurrent fever and acute renal failure. We made the diagnosis of Epstein-Barr virus related HLH based on the HLH-2004 protocol, and gave the treatment of ruxolitinib instead of etoposide.

MANAGEMENT AND OUTCOME

The patient received dexamethasone and continuous renal replacement therapy due to renal failure, but he still had fever and anuria. Given that the use of etoposide may deteriorate renal function, ruxolitinib was administered instead of etoposide. After 5 days of ruxolitinib treatment, the patient's fever was resolved and renal function also gradually recovered 14 days later.

DISCUSSION

Currently, dexamethasone, etoposide and cyclosporine A are the main drugs in HLH treatment. However, cytotoxic chemotherapy can temporally deteriorate organ damage and induce serious myelosuppression, which makes clinicians hesitate to implement these regimens. Ruxolitinib has shown efficacy in treating HLH without much toxicity in clinical trials. Thus, we suggest that ruxolitinib constitutes a treatment option for secondary HLH complicated by severe renal damage which may reduce toxic effects compared with intense chemotherapy.

Renal Diseases Associated with Hematologic Malignancies and Thymoma in the Absence of Renal Monoclonal Immunoglobulin Deposits

In addition to kidney diseases characterized by the precipitation and deposition of overproduced monoclonal immunoglobulin and kidney damage due to chemotherapy agents, a broad spectrum of renal lesions may be found in patients with hematologic malignancies. Glomerular diseases, in the form of paraneoplastic glomerulopathies and acute kidney injury with various degrees of proteinuria due to specific lymphomatous interstitial and/or glomerular infiltration, are two major renal complications observed in the lymphoid disorder setting. However, other hematologic neoplasms, including chronic lymphocytic leukemia, thymoma, myeloproliferative disorders, Castleman disease and hemophagocytic syndrome, have also been associated with the development of kidney lesions. These renal disorders require prompt recognition by the clinician, due to the need to implement specific treatment, depending on the chemotherapy regimen, to decrease the risk of subsequent chronic kidney disease. In the context of renal disease related to hematologic malignancies, renal biopsy remains crucial for accurate pathological diagnosis, with the aim of optimizing medical care for these patients. In this review, we provide an update on the epidemiology, clinical presentation, pathophysiological processes and diagnostic strategy for kidney diseases associated with hematologic malignancies outside the spectrum of monoclonal gammopathy of renal significance.

Inflammatory stress in SARS-COV-2 associated Acute Kidney Injury

Increasing clinical evidence shows that acute kidney injury (AKI) is a common and severe complication in critically ill COVID-19 patients. The older age, the severity of COVID-19 infection, the ethnicity, and the history of smoking, diabetes, hypertension, and cardiovascular disease are the risk factor for AKI in COVID-19 patients. Of them, inflammation may be a key player in the pathogenesis of AKI in patients with COVID-19. It is highly possible that SARS-COV-2 infection may trigger the activation of multiple inflammatory pathways including angiotensin II, cytokine storm such as interleukin-6 (IL-6), C-reactive protein (CRP), TGF-β signaling, complement activation, and lung-kidney crosstalk to cause AKI. Thus, treatments by targeting these inflammatory molecules and pathways with a monoclonal antibody against IL-6 (Tocilizumab), C3 inhibitor AMY-101, anti-C5 antibody, anti-TGF-β OT-101, and the use of CRRT in critically ill patients may represent as novel and specific therapies for AKI in COVID-19 patients.

Kidney injury in COVID-19

Coronavirus disease 2019 (COVID-19) continues to affect millions of people around the globe. As data emerge, it is becoming more evident that extrapulmonary organ involvement, particularly the kidneys, highly influence mortality. The incidence of acute kidney injury has been estimated to be 30% in COVID-19 non-survivors. Current evidence suggests four broad mechanisms of renal injury: Hypovolaemia, acute respiratory distress syndrome related, cytokine storm and direct viral invasion as seen on renal autopsy findings. We look to critically assess the epidemiology, pathophysiology and management of kidney injury in COVID-19.

Hemophagocytic Lymphohistiocytosis During HIV Infection in Cayenne Hospital 2012-2015: First Think Histoplasmosis

Introduction: Haemophagocytic Lymphohistiocytosis (HLH), during HIV infection is a rare complication with a poor prognosis. There are few data on HLH within the Amazon region. The objective was to describe epidemiological, clinical and therapeutic features of HIV-related HLH in French Guiana. Methods: A retrospective analysis of adult HIV patients at Cayenne hospital with HLH between 2012 and 2015. A diagnosis of HLH was given if the patient presented at least 3 of 8 criteria of the HLH-2004 classification. Results: Fourteen cases of HLH were tallied during the study period. The mean age was 46 years with a sex ratio of 1.8. The most frequent etiology of HLH was an associated infection (12/14). Confirmed disseminated histoplasmosis, was found in 10 of 14 cases, and it was suspected in 2 other cases. The CD4 count was below 200/mm3 in 13/14 cases. An HIV viral load >100,000 copies/ml was observed in 13/14 cases. An early treatment with liposomal amphotericin B was initiated in 12/14 cases. The outcome was favorable in 12/14 of all cases and in 10/12 cases involving histoplasmosis. Case fatality was 2/14 among all cases (14.3%) et 1/10 among confirmed disseminated histoplasmosis with HLH (10%). During the study period 1 in 5 cases of known HIV-associated disseminated histoplasmosis in French Guiana was HLH. Conclusion: Histoplasmosis was the most frequent etiology associated with HLH in HIV-infected patients in French Guiana. The prognosis of HLH remains severe. However, a probabilistic empirical first line treatment with liposomal amphotericin B seemed to have a favorable impact on patient survival.

Hemophagocytic syndrome with histiocytic glomerulopathy associated with ovarian serous carcinoma

Histiocytic glomerulopathy, an entity characterized by glomerular infiltration by foamy histiocytes with endothelial injury, has recently been reported as a manifestation of hemophagocytic syndrome. We report a case of histiocytic glomerulopathy in a woman receiving chemotherapy for ovarian serous carcinoma with proteinuria in whom hemophagocytic syndrome was not clinically suspected.

Linfohistiocitosis hemofagocítica en trasplante renal

La linfohistiocitosis hemofagocítica (LHH) posterior al trasplante renal hace referencia a un estado hiperinflamatorio grave, asociado a la activación no controlada de los linfocitos T citotóxicos y macrófagos por causa infecciosas y/o secundaria al tratamiento inmunosupresor. Las causas más prevalentes dentro de las infecciones son la histoplasmosis, la tuberculosis y las infecciones por virus herpes. Se caracteriza por fiebre, organomegalias, citopenias, hiperferritinemia, hipertrigliceridemia y/o hipofibrinogenemia; puede acompañarse con hemofagocitosis documentada en la médula ósea, el hígado u otros órganos. Su curso puede ser fulminante con progresión a falla multisistémica y la muerte.El tratamiento va enfocado a controlar tempranamente la causa desencadenante, reducir la inmunosupresión y controlar la inflamación. En pocos casos es necesario el uso de otros inmunosupresores, quimioterapia o, en situaciones muy seleccionadas, se puede requerir el trasplante de médula ósea.

Hemophagocytic syndrome with acute kidney injury accompanied by erythrophagocytic macrophages in the tubular lumen

Hemophagocytic syndrome (HPS) is a life-threatening syndrome involving excessive immune activation. It is often accompanied by renal involvement known as acute kidney injury (AKI), which is a poor prognostic factor of HPS. Thus, early diagnosis and treatment are very important. However, it is rarely identified in renal biopsy specimens, and its major manifestation is acute tubular necrosis. We report a rare case of erythrophagocytic macrophage presence in the tubular lumen of a patient with HPS-associated AKI. A kidney biopsy showed acute tubular necrosis, interstitial massive macrophage infiltration, and phagocytic macrophage casts without glomerular change. Some arteriolar vascular smooth muscle cells showed vacuolization because they were positive for α-smooth muscle actin. The patient's renal function improved after methylprednisolone pulse therapy followed by oral prednisolone after a month. Our case presents a new pathologic pattern of HPS. Careful urinalysis could suggest renal involvement with HPS. Having knowledge of this pathologic pattern of HPS is important to recognize the disease and to treat it appropriately.

Collapsing glomerulonephritis with podocyte markers in hemophagocytic syndrome secondary to hepatosplenic T-cell lymphoma

The hemophagocytic syndrome is a serious clinical-histological entity secondary to different diseases. Collapsing glomerulonephritis is a proliferative podocytopathy that usually has an unfavorable renal prognosis. We present a case in which both entities were associated, which is an infrequent form of hepatosplenic T-cell lymphoma. In addition, we review the role of the markers of podocyte dedifferentiation in this glomerulopathy and its pathophysiology and treatment.

Hemophagocytic Syndrome With Histiocytic Glomerulopathy and Intraglomerular Hemophagocytosis

Hemophagocytic syndrome (HPS), a rare and life-threatening disease, is characterized by hyperactivation of the immune system that causes hypercytokinemia and potential multiorgan failure. Acute kidney injury is the most common kidney manifestation of HPS and is generally considered a poor prognostic factor. Glomerular involvement is uncommon and usually manifests as either podocytopathy with collapsing glomerulopathy or thrombotic microangiopathy. We report a rare case of severe histiocytic glomerulopathy in a patient with HPS who presented with acute kidney injury and proteinuria. Kidney biopsy revealed massive glomerular infiltration by macrophages resembling proliferative glomerulonephritis accompanied by intraglomerular hemophagocytosis and mild features of glomerular thrombotic microangiopathy. The patient's kidney failure and proteinuria responded rapidly to high-dose pulse methylprednisolone followed by a tapering course of oral prednisone. Our case expands the renal pathologic spectrum of HPS to include histiocyte-rich glomerular infiltration and intraglomerular hemophagocytosis. Greater awareness of this entity is needed to ensure prompt recognition and appropriate therapy.

Acute kidney injury induced by thrombotic microangiopathy in a patient with hemophagocytic lymphohistiocytosis

Background

Hemophagocytic lymphohistiocytosis (HLH) is a fatal clinical syndrome characterized by excessive immune activation and inflammation. It is frequently complicated by acute kidney injury (AKI) that often develops as acute tubular necrosis (ATN). Meanwhile, renal thrombotic microangiopathy (TMA) is a rare pathologic finding that mostly occurs in hemolytic uremic syndrome or thrombotic thrombocytopenic purpura. There are only few reports on TMA developing in patients with HLH. We present here a rare case of TMA associated HLH.

Case presentation

A 60-year-old woman was admitted for a fever of unknown origin that had persisted for several weeks. She presented with AKI and pancytopenia. Clinical, laboratory and bone marrow biopsy findings met the criteria of HLH. Kidney biopsy showed TMA and minimal ATN, which suggested that the primary cause of AKI was TMA in this case. Because of sustained oliguria, we initiated hemodialysis (HD) and also decided to use chemotherapy composed of dexamethasone, etoposide and cyclosporine for treatment of HLH. Six months after the initiation of chemotherapy, pancytopenia was completely resolved, indicating the resolution of HLH. At the same time, serum creatinine decreased to a normal range without the need for HD, suggesting the resolution of TMA.

Conclusion

We report a case of renal TMA associated HLH. This case suggests that renal TMA should be considered as a primary cause of AKI in patients with underlying HLH.

Hemophagocytic Syndrome in Children With Visceral Leishmaniasis

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a serious complication of visceral leishmaniasis (VL). The aim of this study is to describe demographical, clinical and laboratory features of HLH in children with VL.

METHODS

This is a retrospective cohort of children with HLH and VL admitted to a tertiary hospital in Northeast, Brazil, from January 2012 to April 2014. Clinical and laboratory data at admission and during hospital stay were reviewed. Acute kidney injury (AKI) was defined according to the pediatric Risk, Injury, Failure, Loss, End-stage kidney disease criteria.

RESULTS

A total 127 VL children were admitted, and 35 children had diagnosis of HLH. Mean age was 4.2 ± 4.3 years, with 62.9% males. Mean hospital stay was 29 ± 12 days. Main signs and symptoms were fever (100%), splenomegaly (94.2%) and hepatomegaly (60%). Laboratory findings showed pancytopenia, albumin 3.03 ± 0.77 g/dL, fibrinogen 236.1 ± 117.2 mg/dL, total calcium 8.2 ± 1.2 mEq/L, lactate dehydrogenase 1804 ± 1019 mg/dL, alkaline phosphatase 1275.4 ± 2160.5 IU/L, total bilirubin 1.9 ± 2.4 mg/dL, direct bilirubin 0.67 ± 1.02 mg/dL, indirect bilirubin 1.2 ± 2.2 mg/dL, aspartate aminotransferase 140.0 ± 145.3 IU/L, alanine aminotransferase 71.4 ± 81.1 IU/L, ferritin 4296.5 ± 8028.8 ng/dL and triglycerides 333 ± 141 mg/dL. AKI was observed in 16 children (45.7%), predominantly mild forms (93.75% "risk"). AKI group presented lower levels of platelets (69,131 ± 40,247 vs. 138,678 ± 127,494/mm, P = 0.035) than non-AKI. No patient required dialysis and there was no death.

CONCLUSIONS

HLH was not a rare complication of VL. Main symptoms were compatible with both VL and HLH. Main laboratory findings reflected HLH pathophysiology. Mild forms of AKI were a common complication of HLH. Despite the disease severity and complications, mortality was low.

An update on renal involvement in hemophagocytic syndrome (macrophage activation syndrome)

Context: Hemophagocytic syndrome (HPS) is mainly characterized by massive infiltration of bone marrow by activated macrophages and often presents with pancytopenia. Thrombotic microangiopathy (TMA) is also present with thrombocytopenia and renal involvement. Both conditions could coexist with each other and complicate the condition.

Evidence Acquisition: Directory of Open Access Journals (DOAJ), EMBASE, Google Scholar, PubMed, EBSCO, and Web of Science with keywords relevant to; Hemophagocytic syndrome, macrophage activation syndrome, interferon-gamma and thrombotic microangiopathy, have been searched.

Results: Viral infection, rheumatologic disease and malignancies are the main underlying causes for secondary HPS. calcineurin inhibitors and viral infections are also the main underlying causes of TMA in transplant recipients. In this review, we discussed a 39-year-old male who presented with pancytopenia and renal allograft dysfunction. With the diagnosis of HPS induced TMA his renal condition and pancytopenia improved after receiving intravenous immunoglobulin (IVIG) and plasmapheresis therapy.

Conclusions: HPS is an increasingly recognized disorder in the realm of different medical specialties. Renal involvement complicates the clinical picture of the disease, and this condition even is more complex in renal transplant recipients. We should consider the possibility of HPS in any renal transplant recipient with pancytopenia and allograft dysfunction. The combination of HPS with TMA future increases the complexity of the situation.

Direct Reversible Kidney Injury in Familial Hemophagocytic Lymphohistiocytosis Type 3

Hemophagocytic lymphohistiocytosis is a hyperinflammatory disorder resulting from primary or secondary immune dysfunction. AKI is frequent in severe hemophagocytic lymphohistiocytosis and has been attributed to multiorgan failure or the use of nephrotoxic drugs, but AKI is rarely considered a direct consequence of the disease process. We describe a child with familial hemophagocytic lymphohistiocytosis type 3 who developed AKI requiring prolonged renal replacement therapy because of severe renal inflammation. There was massive infiltration of the renal parenchyma by activated macrophages and cytotoxic T cells, and acute tubular injury. The patient responded to high-dose intravenous methylprednisolone, which resulted in improvement of renal function and discontinuation of renal replacement therapy. This case confirms the occurrence of reversible AKI due to hemophagocytic lymphohistiocytosis-induced activated macrophage infiltration of the renal parenchyma and inflammation.

Clinical characteristics, prognostic factors, and outcomes of adult patients with hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a rare clinical syndrome characterized by the activation of the mononuclear phagocytic system. The diagnosis of HLH in adults is challenging not only because the majority of the reported data are from pediatric patients, but also because HLH occurs in many disease entities. This study reports the clinical and laboratory findings and prognostic factors of adult HLH in a large cohort managed at a single medical center from 2003 to 2014. Seventy-three patients met the HLH-2004 diagnostic criteria. The median age was 51 years (range, 18-82 years); 41 (56.2%) were male. Patients manifested fever, cytopenias, and elevated ferritin in >85% of cases. Likely causes of HLH were as follows: 30 (41.1%) infections, 21 (28.8%) malignancies, 5 (6.8%) attributed to autoimmune disorders, 1 (1.4%) primary immunodeficiency, 2 (2.7%) post solid organ transplantation, and 13 (17.8%) idiopathic. The median overall survival was 7.67 months. Patients with malignancy-associated HLH had a markedly worse survival compared with patients with non-malignancy-associated HLH (median overall survival 1.13 vs. 46.53 months, respectively; P < 0.0001). In a multivariable analysis, malignancy (hazard ratio = 12.22; 95% CI: 2.53-59.02; P = 0.002) correlated with poor survival. Ferritin >50,000 µg/L correlated with 30-day mortality. Survival after a diagnosis of HLH is dismal, especially among those with malignancy-associated HLH. The development of a registry for adults with HLH would improve our understanding of this syndrome, validate diagnostic criteria, and help develop effective treatment strategies.

Histiocytic glomerulopathy associated with macrophage activation syndrome

We present an interesting case of a 37-year old man with acute renal failure following a febrile illness. Laboratory results showed features of macrophage activation syndrome (MAS) with anemia, thrombocytopenia, hypofibrinogenemia and elevated ferritin levels. Renal biopsy was then done to determine the cause of renal failure and showed unique glomerular findings with massive histiocytic infiltration ('histiocytic glomerulopathy') and evidence of endothelial injury. Recognizing that the histiocytic infiltrate and endothelial injury is a part of MAS is important because early recognition and treatment is of utmost importance since the disease can be fatal.

Acute kidney injury in adults with hemophagocytic lymphohistiocytosis

BACKGROUND

Acute kidney injury (AKI) in the setting of hemophagocytic lymphohistiocytosis (HLH) is poorly characterized. This study aims to describe the incidence, clinical and biological features, and outcome associated with AKI in this population.

STUDY DESIGN

Case series.

SETTING & PARTICIPANTS

Patients with secondary HLH admitted to a single center from February 2007 through January 2013. 95 patients were included in the study.

PREDICTOR

AKI.

OUTCOMES

Recovery of kidney function, 6-month mortality, and complete remission of the underlying disease.

MEASUREMENTS

AKI was defined according to the KDIGO 2012 guideline. Recovery of kidney function was defined as improvement in serum creatinine level, with return to baseline serum creatinine level ±26.5μmol/L.

RESULTS

HLH was related to hematologic malignancy in 73 (77%), infectious disease in 21 (22%), and autoimmune disease in 9 (10%) patients and was multifactorial in 10 (11%) patients. The cause was undetermined in 2 (2%) patients. The incidence of AKI during HLH is high (62%), and 59% of the AKI population required renal replacement therapy. Main causes of AKI were acute tubular necrosis (49%), hypoperfusion (46%), tumor lysis syndrome (29%), or HLH-associated glomerulopathies (17%). At 6 months, 32% of the patients with AKI had chronic kidney disease. Two factors were associated independently with 6-month mortality by multivariable analysis: AKI stage ≥ 2 (OR, 2.61; 95% CI, 1.08-6.29; P=0.03) and an underlying hematologic malignancy (OR, 3.1; 95% CI, 1.05-9.14; P=0.04). In patients with hematologic malignancy, AKI was associated with lower 6-month complete remission (non-AKI, 25%; AKI patients, 5%; P=0.05).

LIMITATIONS

Retrospective study, lack of histologic data.

CONCLUSIONS

AKI in patients with HLH is frequent and adversely affects remission and survival. Early intensive management, including administration of etoposide, nephrotoxic drug withdrawal, prevention of tumor lysis syndrome, or aggressive supportive care, might improve kidney function and survival.

Hemophagocytic lymphohistiocytosis in a patient with Goodpasture's syndrome: a rare clinical association

Patient: Female, 31

Final Diagnosis: Hemophagocytic lymphohistiocytosis (LHL)

Symptoms: Hemopthysis

Medication: —

Clinical Procedure: —

Specialty: Oncology

Rejection-triggered haemophagocytic syndrome in renal transplantation successfully treated with intravenous immunoglobulin

Haemophagocytic syndrome (HPS) is a rare and potentially lethal condition characterized by pancytopoenia, fever, organomegaly and widespread proliferation of macrophages phagocytosing blood elements. Among the triggers of this syndrome, excessive immunosuppression in a context of acute rejection has been rarely reported, although it might be underdiagnosed. Here, we report the case of a kidney transplant recipient with allograft dysfunction due to chronic antibody-mediated rejection treated with antithymocyte globulin and plasmapheresis. The patient developed high fever, pancytopoenia, diarrhoea and respiratory symptoms with no apparent infectious or neoplastic cause, despite an extensive work-up. Haemophagocytosis was found in bone marrow examination, along with hyperferritinaemia and hypertriglyceridaemia. The clinical profile improved after treatment with intravenous immunoglobulin and reduction of the basal immunosuppression.

Acute kidney injury in patients with newly diagnosed high-grade hematological malignancies: impact on remission and survival

Background

Optimal chemotherapy with minimal toxicity is the main determinant of complete remission in patients with newly diagnosed hematological malignancies. Acute organ dysfunctions may impair the patient’s ability to receive optimal chemotherapy.

Design and Methods

To compare 6-month complete remission rates in patients with and without acute kidney injury (AKI), we collected prospective data on 200 patients with newly diagnosed high-grade malignancies (non-Hodgkin lymphoma, 53.5%; acute myeloid leukemia, 29%; acute lymphoblastic leukemia, 11.5%; and Hodgkin disease, 6%).

Results

According to RIFLE criteria, 137 (68.5%) patients had AKI. Five causes of AKI accounted for 91.4% of cases: hypoperfusion, tumor lysis syndrome, tubular necrosis, nephrotoxic agents, and hemophagocytic lymphohistiocytosis. Half of the AKI patients received renal replacement therapy and 14.6% received suboptimal chemotherapy. AKI was associated with a lower 6-month complete remission rate (39.4% vs. 68.3%, P<0.01) and a higher mortality rate (47.4% vs. 30.2%, P<0.01) than patients without AKI. By multivariate analysis, independent determinants of 6-month complete remission were older age, poor performance status, number of organ dysfunctions, and AKI.

Conclusion

AKI is common in patients with newly diagnosed high-grade malignancies and is associated with lower complete remission rates and higher mortality.

Hemophagocytic lymphohistiocytosis: pathogenesis and treatment

Hemophagocytic lymphohistiocytosis (HLH) is not an independent disease but rather a life-threatening clinical syndrome that occurs in many underlying conditions and in all age groups. HLH is the consequence of a severe, uncontrolled hyperinflammatory reaction that in most cases is triggered by an infectious agent. Persistent stimulation of lymphocytes and histiocytes results in hypercytokinemia, leading to the characteristic symptoms of HLH. Genetic defects in familial HLH and in immunodeficiency syndromes associated with albinism affect the transport, processing, and function of cytotoxic granules in natural killer cells and cytotoxic T lymphocytes. This leads to defective killing of target cells and a failure to contract the immune response. The defects are increasingly found also in adolescents and adults. Acquired HLH occurs in autoinflammatory and autoimmune diseases (macrophage activation syndrome) and in patients with iatrogenic immunosuppression or with malignancies, but also in otherwise healthy persons with infections. Treatment of HLH aims at suppressing hypercytokinemia and eliminating the activated and infected cells. In genetic HLH, hematopoietic stem cell transplantation (HSCT) is needed for the correction of the immune defect. Treatment modalities include immunosuppressive, immunomodulatory, and cytostatic drugs; T-cell antibodies; and anticytokine agents. Using immunochemotherapy, familial HLH, which had been invariably fatal, has become a curable disease with more than 50% survivors. Reduced intensity conditioning for HSCT, which is associated with less transplantation-related mortality, will further improve cure rates.

Glomerular hemophagocytic macrophages in a patient with proteinuria and clinical and laboratory features of hemophagocytic lymphohistiocytosis (HLH)

Hemophagocytic lymphohistiocytosis (HLH) is a heterogeneous disorder characterized by excessive activation and proliferation of nonmalignant histiocytes, which are commonly found in bone marrow, lymph nodes, spleen and liver in affected patients. Here, we report the presence of glomerular macrophages, including one showing erythrophagocytosis, on renal biopsy in a 25-year-old patient with clinical presentation and laboratory changes consistent with HLH. The clinical course was marked by persistent fever for 2 months, pleural and pericardial effusion, splenomegaly, lymphadenopathy, pancytopenia, cardiac arrhythmias, multiple organ dysfunction, and proteinuria, with demise after a 2-month hospitalization. Positive assay for Epstein-Barr virus (EBV), marked hyperferritinemia, hypofibrinogenemia, hypertriglyceridemia, elevated anti-nuclear antibody, proteinuria, and decreased circulating NK cells by flow cytometry were compatible with the diagnosis of HLH. We suggest that the glomerular hemophagocytic macrophages, which have not heretofore been described in the kidney of a patient with HLH, may have contributed to renal dysfunction manifest as proteinuria.

Hemophagocytic syndrome in a patient with acute tubulointerstitial nephritis secondary to hepatitis A virus infection

Hepatitis A virus (HAV) infection is generally a self-limited disease, but the infection in adults can be serious, to be often complicated by acute kidney injury (AKI) and rarely by virus-associated hemophagocytic syndrome (VAHS). Our patient, a 48-yr-old man, was diagnosed with HAV infection complicated by dialysis-dependent AKI. His kidney biopsy showed acute tubulointerstitial nephritis with massive infiltration of activated macrophages and T cells, and he progressively demonstrated features of VAHS. With hemodialysis and steroid treatment, he was successfully recovered.