Macrophage activation syndrome: early diagnosis is key

Emergencies in inflammatory rheumatic diseases

Inflammatory rheumatic diseases (IRDs), encompassing a broad spectrum of chronic disorders, typically necessitate prolonged therapeutic intervention. Nevertheless, these diseases can sometimes manifest as severe emergencies requiring prompt and extensive medical intervention. Urgent intervention is essential for effectively recognizing and managing these situations, as they have the potential to be life-threatening and can result in severe morbidity and mortality. Emergencies in IRDs can occur with different frequencies and manifestations, including nervous system issues, severe infections, thrombosis-emboli, renal crises, gastrointestinal issues, and cardiovascular events. The fact that these events can occur across different IRDs underscores the necessity for heightened awareness and readiness among healthcare professionals. The pathophysiologic mechanisms that cause rheumatic emergencies are complex and involve multiple factors. These emergencies frequently arise due to the interplay between the inflammatory characteristics of rheumatic diseases and different systemic triggers. Early detection and treatment can have a substantial impact on an individual's prognosis in cases of severe and life-threatening disorders that require prompt recognition. Rapid decision-making and urgent care are required to effectively address rheumatic emergencies, as well as the implementation of a diagnostic flowchart. This article provides an overview of the emergencies linked to IRDs, classifying and assessing them individually. This article aims to enhance healthcare professionals' knowledge and awareness of critical situations by examining current recommendations and pathophysiological information. Implementing standardized diagnostic and treatment methods, providing patient education, and conducting continuing research into the underlying mechanisms are essential for enhancing the management of these critical situations and improving patient outcomes.

Chloroquine regulates the lipopolysaccharide-induced inflammatory response in RAW264.7 cells

INTRODUCTION AND OBJECTIVES

Macrophage-induced inflammation plays a key role in defense against injury and harmful pathogens. Autophagy and the inflammatory response are associated; however, the relationship between the autophagy pathway and lipopolysaccharide (LPS)- induced inflammatory responses remains unknown. We aimed to determine the effect of autophagy on the LPS-induced myeloid differentiation factor 88 (MyD88)/nuclear transcription factor kB (NF-kB) pathway-mediated inflammatory response in RAW264.7 cells.

MATERIALS AND METHODS

To determine the effect of autophagy on the LPS-induced inflammatory response, using various in vitro assays, we determined the effect of autophagy inhibitors and inducers on the inflammatory response in RAW264.7 cells.

RESULTS

Chloroquine (CQ), an autophagy inhibitor, suppressed pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6, and tumor necrosis factor α (TNFα) in LPS-stimulated RAW264.7 cells. CQ also affected inflammatory mediators such as myeloid differentiation factor 88 and NF-kB in LPS-stimulated RAW264.7 cells.

CONCLUSION

This study demonstrated that CQ regulates the LPS-induced inflammatory response in RAW264.7 cells. We propose that targeting the regulation of pro-inflammatory cytokine levels and inflammatory mediators using CQ is a promising therapeutic approach for preventing inflammatory injury. CQ serves as a potential therapeutic target for treating various inflammatory diseases.

Disrupting B and T-cell collaboration in autoimmune disease: T-cell engagers versus CAR T-cell therapy?

B and T cells collaborate to drive autoimmune disease (AID). Historically, B- and T-cell (B-T cell) co-interaction was targeted through different pathways such as alemtuzumab, abatacept, and dapirolizumab with variable impact on B-cell depletion (BCD), whereas the majority of patients with AID including rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis, and organ transplantation benefit from targeted BCD with anti-CD20 monoclonal antibodies such as rituximab, ocrelizumab, or ofatumumab. Refractory AID is a significant problem for patients with incomplete BCD with a greater frequency of IgD-CD27+ switched memory B cells, CD19+CD20- B cells, and plasma cells that are not directly targeted by anti-CD20 antibodies, whereas most lymphoid tissue plasma cells express CD19. Furthermore, B-T-cell collaboration is predominant in lymphoid tissues and at sites of inflammation such as the joint and kidney, where BCD may be inefficient, due to limited access to key effector cells. In the treatment of cancer, chimeric antigen receptor (CAR) T-cell therapy and T-cell engagers (TCE) that recruit T cells to induce B-cell cytotoxicity have delivered promising results for anti-CD19 CAR T-cell therapies, the CD19 TCE blinatumomab and CD20 TCE such as mosunetuzumab, glofitamab, or epcoritamab. Limited evidence suggests that anti-CD19 CAR T-cell therapy may be effective in managing refractory AID whereas we await evaluation of TCE for use in non-oncological indications. Therefore, here, we discuss the potential mechanistic advantages of novel therapies that rely on T cells as effector cells to disrupt B-T-cell collaboration toward overcoming rituximab-resistant AID.

Single center clinical analysis of macrophage activation syndrome complicating juvenile rheumatic diseases

BACKGROUND

Macrophage activation syndrome (MAS), an example of secondary hemophagocytic lymphohistiocytosis, is a potentially fatal complication of rheumatic diseases. We aimed to study the clinical and laboratory characteristics, treatment schemes, and outcomes of different rheumatic disorders associated with MAS in children. Early warning indicators of MAS have also been investigated to enable clinicians to make a prompt and accurate diagnosis.

METHODS

Fifty-five patients with rheumatic diseases complicated by MAS were enrolled between January 2017 and December 2022. Clinical and laboratory data were collected before disease onset, at diagnosis, and after treatment with MAS, and data were compared between patients with systemic juvenile idiopathic arthritis (sJIA), Kawasaki disease (KD), and systemic lupus erythematosus (SLE). A random forest model was established to show the importance score of each variable with a significant difference.

RESULTS

Most (81.8%) instances of MAS occurred during the initial diagnosis of the underlying disease. Compared to the active stage of sJIA, the platelet count, erythrocyte sedimentation rate, and fibrinogen level in sJIA-MAS were significantly decreased, whereas ferritin, ferritin/erythrocyte sedimentation rate, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and D-dimer levels were significantly increased. Ferritin level, ferritin/erythrocyte sedimentation rate, and platelet count had the greatest predictive value for sJIA-MAS. The level of IL-18 in the sJIA-MAS group was significantly higher than in the active sJIA group, whereas IL-6 levels were significantly lower. Most patients with MAS were treated with methylprednisolone pulse combined with cyclosporine, and no deaths occurred.

CONCLUSIONS

Thrombocytopenia, ferritin levels, the ferritin/erythrocyte sedimentation rate, and elevated aspartate aminotransferase levels can predict the occurrence of MAS in patients with sJIA. Additionally, our analysis indicates that IL-18 plays an important role in the pathogenesis of MAS in sJIA-MAS.

A MASsive attack: a pediatric case of macrophage activation syndrome complicated by DIC as an onset of systemic juvenile idiopathic arthritis successfully treated with anakinra and review of the literature

Macrophage activation syndrome (MAS) is one of the most severe complications of systemic juvenile idiopathic arthritis (sJIA). Around 10% of patients with sJIA exhibit systemic symptoms accompanied by macrophage activation syndrome (MAS), but it may occur subclinically in another 30-40%. In this article, we present a case of a 3-year-old girl diagnosed with sever MAS as an onset of sJIA complicated by disseminated intravascular coagulation (DIC). First symptoms of sJIA were observed about 5 months before setting the diagnose, and it was resembling urticaria. A comprehensive allergological diagnostics were conducted, but no cause for the skin changes was identified. A few weeks before admission to the hospital, the girl was presented with a high fever. During the hospital stay, viral, bacterial, and fungal infections were ruled out. However, the findings indicated significantly elevated markers of inflammation (ferritin, CRP, ESR) in the conducted tests. Meanwhile, swelling of the feet and ankle joints was also observed. Based on Ravelli criteria, we set the diagnosis of MAS in a course of sJIA. We implemented treatment with steroid pulses, followed by cyclosporine; however, her clinical condition did not improve. Despite intensive treatment, skin petechiae were observed twice, and laboratory tests revealed a very high INR along with an extremely low level of fibrinogen. The patient required multiple plasma transfusions and clotting factor administrations. Due to the severe condition of the girl, we initiated biological treatment with anakinra, after which the child's condition gradually improved. In this case, we want to present how dynamic and life-threatening the course of MAS can be. In the discussion, we are also comparing our approach and the applied treatment with the currently available knowledge.

Disseminated Histoplasmosis Mimicking Macrophage Activation Syndrome in a Patient With Rheumatoid Arthritis

Infections caused by Histoplasma capsulatum typically do not produce symptoms. However, in individuals who are immunocompromised, progressive disseminated histoplasmosis may occur. A 67-year-old female, with lengthy history of immunosuppression due to management of rheumatoid arthritis, reported a two-month history of fatigue, headaches, and intermittent fevers following hip surgery. Due to the concern for macrophage activation syndrome and hemophagocytic lymphohistiocytosis, a bone marrow biopsy was performed. However, the results indicated the presence of Histoplasma, which was supported by the presence of Histoplasma antigens in the serum and urine, Histoplasma antibodies in the serum, positive (1,3)-beta-D-glucan results, and fungal blood cultures. The patient initially received amphotericin B, but it was switched to itraconazole due to adverse effects. The patient remains on itraconazole therapy and follows as an outpatient with an infectious diseases specialist.

Liver Dysfunction in Adult Hemophagocytic Lymphohistiocytosis: A Narrative Review

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening condition that has been increasingly recognized in adults and is characterized by a hyperinflammatory state due to immune dysregulation. Its nonspecific presentation, the lack of clinician familiarity given its rarity, and shared clinical features with sepsis and other syndromes can lead to a delay in diagnosis and a poor prognosis. Significant liver function abnormalities as the initial manifestation of HLH are uncommon and can range from mild elevation of aminotransferases to fulminant hepatic failure with high mortality rates. The authors encountered a case of adult HLH mimicking acute viral hepatitis in which a markedly elevated ferritin level led to a prompt diagnosis, early initiation of treatment, and a successful outcome. Clinicians, including gastroenterologists and hepatologists, are often called upon to evaluate patients with abnormal liver tests and may lack experience in the early diagnosis and management of liver dysfunction in the context of HLH. Thus, we expand our reporting to a narrative review of literature which explores the pathogenesis of HLH, challenges associated with its diagnosis, previous reports of liver disease associated with the syndrome, recommended treatments for the familial and adult variations including the role of liver transplantation, and the outcomes of these treatments.

Using Diagnostic Radiological Imaging Modalities to Explore Neurological Dysfunction and Renal Failure in the Intersection of Hemophagocytic Lymphohistiocytosis, Macrophage Activation Syndrome, and Lupus

This comprehensive case report and literature review explore the intricate intersection of hemophagocytic lymphohistiocytosis (HLH), macrophage activation syndrome (MAS), and systemic lupus erythematosus (SLE) in a 39-year-old patient, emphasizing the challenging diagnostic and therapeutic landscape. The patient's journey includes neurological dysfunction, renal failure, and clinical complexities, showcasing the rarity of these overlapping conditions. The report explains the diagnostic process, clinical and laboratory findings, specialty consultations, and treatment decisions leading to the diagnosis of SLE with features of MAS overlapping with HLH. By offering insights into the latest research and clinical perspectives, this case report contributes to a deeper understanding of these disorders, aiming to guide clinicians in recognizing and managing such intricate cases effectively.

A fatal case of hemophagocytic lymphohistiocytosis due to neonatal lupus erythematosus

Neonatal lupus erythematosus (NLE) is an autoimmune disease caused by the passive transfer of autoantibodies from mother to child during pregnancy. A rare complication of NLE is hemophagocytic lymphohistiocytosis (HLH), a potentially life-threatening hyperinflammatory state more commonly associated with other rheumatologic disorders. Herein, we describe a fatal case of NLE-associated HLH.

Adjunctive use of oral MAF is associated with no disease progression or mortality in hospitalized patients with COVID-19 pneumonia: The single-arm COral-MAF1 prospective trial

Based on a growing body of evidence that a dysregulated innate immune response mediated by monocytes/macrophages plays a key role in the pathogenesis of COVID-19, a clinical trial was conducted to investigate the therapeutic potential and safety of oral macrophage activating factor (MAF) plus standard of care (SoC) in the treatment of hospitalized patients with COVID-19 pneumonia. Ninety-seven hospitalized patients with confirmed COVID-19 pneumonia were treated with oral MAF and a vitamin D3 supplement, in combination with SoC, in a single-arm, open label, multicentre, phase II clinical trial. The primary outcome measure was a reduction in an intensive care unit transfer rate below 13% after MAF administration. At the end of the study, an additional propensity score matching (PSM) analysis was performed to compare the MAF group with a control group treated with SoC alone. Out of 97 patients treated with MAF, none needed care in the ICU and/or intubation with mechanical ventilation or died during hospitalization. Oxygen therapy was discontinued after a median of nine days of MAF treatment. The median length of viral shedding and hospital stay was 14 days and 18 days, respectively. After PSM, statistically significant differences were found in all of the in-hospital outcomes between the two groups. No mild to serious adverse events were recorded during the study. Notwithstanding the limitations of a single-arm study, which prevented definitive conclusions, a 21-day course of MAF treatment plus SoC was found to be safe and promising in the treatment of hospitalized adult patients with COVID-19 pneumonia. Further research will be needed to confirm these preliminary findings.

Case report: Hemophagocytic lymphohistiocytosis complicated by multiple organ dysfunction syndrome following aseptic encephalitis

Hemophagocytic lymphohistiocytosis (HLH) is a rare but potentially life-threatening condition caused by excessive immune activation. Secondary HLH is usually triggered by infection, most often from viral infection or malignancy. Here, we present a case of secondary HLH, complicated by multiple organ dysfunction syndrome triggered by critical aseptic encephalitis. A 27-year-old man without any underlying disease presented to our hospital with fever, disturbance of consciousness, and generalized seizures. The patient was diagnosed with aseptic encephalitis with super-refractory status epilepticus. Although antiseizure medications and immunoglobulins were administered, the patient developed multiple organ dysfunction syndrome. HLH was later diagnosed based on hypertriglyceridemia, hyperferritinemia, splenomegaly, cytopenia, and phagocytosis of nucleated cells, as shown by a blood smear of bone marrow aspiration. Treatment with pulse steroid therapy and plasmapheresis was initiated rather than chemotherapy because of the patient's critical condition. However, the patient died of profound shock and multiple organ failure. Diagnosis of HLH is challenging in patients with severe infections because of similar clinical manifestations and laboratory findings. The early recognition of HLH provides patients with the opportunity to receive appropriate treatment, which can lead to increased survival and remission rates.

Exploring the anti-inflammatory activity of sulforaphane

Dysregulation of innate immune responses can result in chronic inflammatory conditions. Glucocorticoids, the current frontline therapy, are effective immunosuppressive drugs but come with a trade-off of cumulative and serious side effects. Therefore, alternative drug options with improved safety profiles are urgently needed. Sulforaphane, a phytochemical derived from plants of the brassica family, is a potent inducer of phase II detoxification enzymes via nuclear factor-erythroid factor 2-related factor 2 (NRF2) signaling. Moreover, a growing body of evidence suggests additional diverse anti-inflammatory properties of sulforaphane through interactions with mediators of key signaling pathways and inflammatory cytokines. Multiple studies support a role for sulforaphane as a negative regulator of nuclear factor kappa-light chain enhancer of activated B cells (NF-κB) activation and subsequent cytokine release, inflammasome activation and direct regulation of the activity of macrophage migration inhibitory factor. Significantly, studies have also highlighted potential steroid-sparing activity for sulforaphane, suggesting that it may have potential as an adjunctive therapy for some inflammatory conditions. This review discusses published research on sulforaphane, including proposed mechanisms of action, and poses questions for future studies that might help progress our understanding of the potential clinical applications of this intriguing molecule.

Macrophage activation syndrome in a patient with systemic lupus erythematosus undergoing cyclophosphamide treatment: a case report

Macrophage activation syndrome (MAS) is a disorder related to hemophagocytic lymphohistiocytosis and is a life-threatening complication of rheumatic diseases. The diagnosis is challenging because MAS symptoms are quite similar to those of many active autoimmune diseases or severe sepsis. We describe the case of a female patient with systemic lupus erythematosus that presented with symptoms suggesting acute decompensation of autoimmune disease and sepsis. She was later diagnosed with MAS. Despite an aggressive immunosuppressive treatment, she developed a fatal outcome.

Systemic lupus erythematosus associated with development of macrophage activation syndrome and disseminated aspergillosis

PURPOSE

Macrophage activation syndrome (MAS) is a rare illness, especially in critically ill adults. The diagnosis of MAS is challenging, requiring the expertise of multiple specialists, and treatments for MAS can be associated with catastrophic complications.

CLINICAL FEATURES

We describe the case of a 31-yr-old Vietnamese student who was diagnosed with cutaneous systemic lupus erythematosus (SLE) in November 2020 and was initiated on treatment with low-dose corticosteroids and hydroxychloroquine as an outpatient. Ten days later, she presented to hospital with decreased consciousness, fever, periorbital swelling, and hypotension necessitating intubation. Computed tomography angiography (CTA) and lumbar puncture did not show a stroke or central nervous system infection. Serology and clinical presentation were consistent with MAS. She was initially treated with 4.5 g pulse methylprednisolone and subsequently with the interleukin-1 receptor antagonist, anakinra, and maintenance corticosteroids because of persistently elevated inflammatory markers. Her intensive care unit stay was complicated by aspiration, airway obstruction due to fungal tracheobronchitis necessitating extracorporeal membrane oxygenation (ECMO), and ring-enhancing cerebral lesions, and, ultimately, massive hemoptysis resulting in death.

CONCLUSIONS

Four features of this case merit discussion, including the: 1) infrequent association of SLE with MAS; 2) short interval between SLE diagnosis and critical illness; 3) manifestation of fungal tracheobronchitis with airway obstruction; and 4) lack of response to antifungal treatment while receiving ECMO.

[Clinical features of Kawasaki disease complicated by macrophage activation syndrome: an analysis of 27 cases]

OBJECTIVES

To investigate the clinical manifestations and laboratory examination results of children with Kawasaki disease complicated by macrophage activation syndrome (KD-MAS), and to provide a basis for identifying early warning indicators for the early diagnosis and treatment of KD-MAS.

METHODS

A retrospective study was performed on 27 children with KD-MAS (KD-MAS group) and 110 children with KD (KD group) who were admitted to Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology, from January 2014 to January 2022. Clinical and laboratory data were compared between the two groups. The receiver operating characteristic (ROC) curve was used to investigate the value of laboratory markers with statistical significance in the diagnosis of KD-MAS.

RESULTS

Compared with the KD group, the KD-MAS group had significantly higher incidence rates of hepatomegaly, splenomegaly, incomplete KD, no response to intravenous immunoglobulin, coronary artery damage, multiple organ damage, and KD recurrence, as well as a significantly longer length of hospital stay (P<0.05). Compared with the KD group, the KD-MAS group had significantly lower levels of white blood cell count, absolute neutrophil count, hemoglobin, platelet count (PLT), erythrocyte sedimentation rate, serum albumin, serum sodium, prealbumin, and fibrinogen (FIB), a significantly lower incidence rate of non-exudative conjunctiva, and significantly higher levels of C-reactive protein, alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase (LDH), and serum ferritin (SF) (P<0.05). The ROC curve analysis showed that SF, PLT, FIB, and LDH had high value in the diagnosis of KD-MAS, with areas under the curve (AUC) of 0.989, 0.966, 0.932, and 0.897, respectively (P<0.001), and optimal cut-off values of 349.95 μg/L, 159×10⁹/L, 3.85 g/L, and 403.50 U/L, respectively. The combination of SF, PLT, FIB, and LDH had a larger AUC than PLT, FIB, and LDH alone in the diagnosis of KD-MAS (P<0.05), but there was no significant difference in the AUC between the combination of SF, PLT, FIB, and LDH and SF alone (P>0.05).

CONCLUSIONS

KD-MAS should be considered when children with KD have hepatosplenomegaly, no response to intravenous immunoglobulin, coronary artery damage, and KD recurrence during treatment. SF, PLT, FIB, and LDH are of high value in the diagnosis of KD-MAS, especially SF is of great significance in the diagnosis of KD-MAS.

Reactivation of Parvovirus B19 Infection: An Uncommon Trigger of Macrophage Activation Syndrome in Adult-Onset Still's Disease

A 40-year-old woman presented with four weeks of intermittent high-grade fever, cough, and joint pain, and two weeks of a generalized rash. She was found to have adult-onset Still's disease (AOSD) and rapidly developed macrophage activation syndrome (MAS) on the second day of admission. Among infectious etiologies, Epstein-Barr virus and members of the herpes virus family are common triggers of MAS. However, our patient was found to have reactivation/recurrence of parvovirus B19 infection as the cause; this is an uncommon trigger reported infrequently in the medical literature. Despite intensive treatment, the patient passed away.

Prognostic factors in patients with bone marrow hemophagocytosis and its association with hematologic malignancies

Hemophagocytic lymphohistiocytosis (HLH) is a heterogeneous group of hyperinflammatory statuses that are difficult to diagnose and can be life-threatening. Bone marrow (BM) hemophagocytosis is one of the diagnostic criteria according to HLH 2004 diagnostic criteria and HS score. Limited studies have focused on the prognostic factors of BM hemophagocytosis and its association with hematologic malignancies. We aimed to analyze the clinical significance of BM hemophagocytosis. Patients with BM hemophagocytosis, either by cytology or pathology, were enrolled at Taipei Veterans General Hospital from January 2002 to July 2021. Relevant clinical and laboratory data were extracted from medical records. Of 119 patients with BM hemophagocytosis, 57 were diagnosed with hematologic malignancies. The median age of the patients was 58, ranging from 21 to 90. Splenomegaly (adjusted odds ratio [aOR] 2.96; 95% confidence interval [CI] 1.13-7.79) was a risk factor for hematologic malignancies, while autoimmune disease (aOR 0.07; 95% CI 0.01-0.39) and increased D-dimer (aOR 0.25; 95% CI 0.07-0.92) were protective factors. Risk factors for mortality in patients with BM hemophagocytosis were hematologic malignancies (adjusted hazard ratio [aHR] 2.34; 95% CI 1.24-4.44), Eastern Cooperative Oncology Group score ≥3 (aHR 2.42; 95% CI 1.20-4.89) and thrombocytopenia (aHR 3.09; 95% CI 1.04-9.16). In conclusion, among patients with BM hemophagocytosis, splenomegaly was a predictor of hematologic malignancies. Patients with hematologic malignancies, poor performance status, or thrombocytopenia had a higher mortality risk. Further validation studies are warranted.

Rituximab, Intravitreal Bevacizumab and Laser Photocoagulation for Treatment of Macrophage Activation Syndrome and Retinal Vasculitis in Lupus: A Case Report

Systemic lupus erythematosus (SLE) most commonly manifests as mild to moderate disease with severe manifestations such as diffuse alveolar hemorrhage, central nervous system vasculitis, macrophage activation syndrome (MAS) or retinal vasculitis (RV) with visual disturbances occurring in a significantly smaller proportion of patients, most of whom have a poor outcome. Macrophage activation syndrome and RV are insufficiently early and rarely recognized presentations of lupus-consequently there are still no treatment recommendations. Here we present the course of diagnosis and treatment of a patient with an SLE flare that resulted in both life-threatening disease (MAS) and vision-threatening disease (RV). The patient was successfully treated with systemic immunosuppressives, a high dose of glucocorticoids and rituximab (RTX), in parallel with intraocular therapy, intravitreal bevacizumab (BEV) and laser photocoagulation.

Case report: Thrombotic microangiopathy concomitant with macrophage activation syndrome in systemic lupus erythematosus refractory to conventional treatment successfully treated with eculizumab

Thrombotic microangiopathy (TMA) is a rare but life-threatening complication of systemic lupus erythematosus (SLE). Macrophage activation syndrome (MAS) is also a rare, life-threatening hyperinflammatory condition that is comorbid with SLE. However, the association between TMA and MAS in patients with SLE has rarely been assessed, and the difficulty of diagnosing these conditions remains prevalent. The efficacy of eculizumab has been reported for SLE patients whose conditions are complicated with TMA. However, no study has investigated the therapeutic efficacy of eculizumab for TMA concomitant with SLE-associated MAS. Herein, we report the first case of TMA concomitant with SLE-associated MAS that was initially refractory to conventional immunosuppressive therapy but showed remarkable recovery after eculizumab treatment. Furthermore, we evaluated serum syndecan-1 and hyaluronan levels, which are biomarkers of endothelial damage. We found that these levels decreased after the administration of eculizumab, suggesting that TMA was the main pathology of the patient. This case illustrates that it is important to appropriately assess the possibility of TMA during the course of SLE-associated MAS and consider the use of eculizumab as necessary.

[Clinical analysis of 5 cases of dermatomyositis complicated with macrophage activation syndrome]

To investigate the clinical and immunological features of dermatomyositis (DM) complicated with macrophage activation syndrome (MAS). The demographic and clinical characteristics of five patients diagnosed with DM complicated with MAS hospitalized in the Department of Rheumatology and Immunology, Peking University People ' s Hospital from 2011 to 2021 were collected. The results of clinical manifestations, laboratory tests, immunological features, treatments and prognosis were analyzed and summarized. In this study, five female patients in Peking University People's Hospital with an average age of 63.8 (44.0-83.0) years and an average disease duration of 16.1 (1.5-48.0) months. All the patients had typical DM rash (such as heliotrope sign, V/shawl sign or Gottron's sign/papules). They all had muscle involvement (including myalgia or muscle weakness). Two patients had positive myositis-specific antibodies (MSAs), in which case 1 had anti-TIF1-γ antibody and case 5 had anti-NXP-2 antibody. Four patients had interstitial lung disease except case 3. All of the cases developed MAS in the active stage of DM. Common manifestations of MAS in these five patients included high-grade fever, cytopenia, decreased fibrinogen, elevated ferritin and increased soluble CD25. Case 1 presented with neutropenia (0.6×10⁹ /L), thrombocytopenia (26.0×10⁹ /L), hypofibrinogenemia (0.9 g/L), markedly elevated ferritin (26 331.0 μg/L), decreased NK cell activity. Case 2 had anaemia (hemoglobin 81.0 g/L), thrombocytopenia (55.0×10⁹ /L), hypertriglyceridemia (4.7 mmol/L), hypofibrinogenemia (1.2 g/L), elevated ferritin (>100 000.0 μg/L), hemophagocytosis in bone marrow. Case 3 had anaemia (hemoglobin 88 g/L), decreased fibrinogen (1.9 g/L), increased ferritin (>27 759.0 μg/L), splenomegaly, hemophagocytosis in bone marrow. Case 4 suffered from neutropenia(0.3×10⁹ /L), anaemia(hemoglobin 78 g/L), hypertriglyceridemia (4.2 mmol/L), hypofibrinogenemia (0.9 g/L), increased ferritin (>100 000.0 μg/L), and decreased NK cell activity. Case 5 presented anaemia (hemoglobin 60.0 g/L), thrombocytopenia (67.0×10⁹ /L), hypertriglyceridemia (12.7 mmol/L), decreased fibrinogen (1.1 g/L), and elevated ferritin (>923.0 μg/L). All the patients were treated with methylprednisone pulse therapy (200-500 mg) combined with cyclosporine while case 5 received rituximab after methylprednisone pulses. In addition, case 3 also received the combination of mycophenolate mofetil. Case 1 was given etoposide while case 4 was treated with cyclophosphamide and repeated plasmapheresis at the same time. Moreover, intravenous immunoglobulin was added meantime apart from case 3. The condition of four patients improved significantly, nevertheless case 4 experienced recurred pulmonary symptoms and died of respiratory failure. As for complications about infection, case 2 had bacterial infection with high level procalcitonin (PCT) before MAS treatment and condition was improved after empiric antibacterial therapy. Case 3 had cytomegalovirus DNAemia before diagnosis of MAS and viral titer turned negative after ganciclovir therapy. After treatment of MAS, four patients developed cytomegalovirus DNAemia except case 3, in which case 5 was co-infected with bacteria. To sum, DM complicated with MAS is relatively rare, and its patients are of ten in life-threatening condition. Early detection, treatment and prevention of infection during treatment are critical to improve the prognosis.

Efficacy, Safety, and Challenges of CAR T-Cells in the Treatment of Solid Tumors

Immunotherapy has been the fifth pillar of cancer treatment in the past decade. Chimeric antigen receptor (CAR) T-cell therapy is a newly designed adoptive immunotherapy that is able to target and further eliminate cancer cells by engaging with MHC-independent tumor-antigens. CAR T-cell therapy has exhibited conspicuous clinical efficacy in hematological malignancies, but more than half of patients will relapse. Of note, the efficacy of CAR T-cell therapy has been even more disappointing in solid tumors. These challenges mainly include (1) the failures of CAR T-cells to treat highly heterogeneous solid tumors due to the difficulty in identifying unique tumor antigen targets, (2) the expression of target antigens in non-cancer cells, (3) the inability of CAR T-cells to effectively infiltrate solid tumors, (4) the short lifespan and lack of persistence of CAR T-cells, and (5) cytokine release syndrome and neurotoxicity. In combination with these characteristics, the ideal CAR T-cell therapy for solid tumors should maintain adequate T-cell response over a long term while sparing healthy tissues. This article reviewed the status, clinical application, efficacy, safety, and challenges of CAR T-cell therapies, as well as the latest progress of CAR T-cell therapies for solid tumors. In addition, the potential strategies to improve the efficacy of CAR T-cells and prevent side effects in solid tumors were also explored.

Variation of Diagnostic Approaches and Treatment Practices for Hemophagocytic Lymphohistiocytosis/Macrophage Activation Syndrome Among Pediatric Subspecialists

OBJECTIVE

To assess the diagnostic and treatment practices among a variety of subspecialists at pediatric institutions in the US.

STUDY DESIGN

Using a web-based survey, we assessed the consultation, diagnostic, and treatment preferences of providers from the different pediatric subspecialties who care for pediatric patients with hemophagocytic lymphohistiocytosis (HLH)/macrophage activating syndrome (MAS). Domains included demographics, provider training level and specialty, experience and comfort level with the diagnosis and treatment of HLH/MAS, and institutional approaches toward the diagnosis and management of HLH/MAS. Participants also were given 2 case scenarios: one describing Epstein-Barr virus-associated HLH and another describing an underlying rheumatologic condition with MAS.

RESULTS

Of 263 respondents, 23%, 29%, 39%, and 7% identified as hematology/oncology, rheumatology, general pediatrics/critical care/hospitalist, and allergy/immunology, respectively. For Epstein-Barr virus/HLH, hematology/oncology was the preferred first consultant by most respondents other than rheumatologists, of whom only 47% agreed. For MAS, 92% of respondents from all specialties favored a rheumatology consultation. Preferred diagnostic tests varied by subspecialty, with hematology/oncology more likely than rheumatology to order an infectious workup, natural killer cell function, soluble interleukin-2 receptor, bone marrow biopsy, and genetic testing. First-line therapy also varied, with hematology/oncology preferring dexamethasone and etoposide and rheumatology more often preferring methylprednisolone and anakinra. One-half of respondents were unaware of institutional algorithms for diagnosis and treatment of HLH/MAS. Most (85.6%) favored the development of treatment algorithms for HLH/MAS, and 90% supported a multidisciplinary approach.

CONCLUSIONS

Current consulting patterns, diagnostic workup, and treatment approaches of HLH/MAS vary by specialty, highlighting the need for standardized management algorithms and institutional multidisciplinary HLH/MAS teams.

Diagnosing Hemophagocytic Lymphohistiocytosis with Machine Learning: A Proof of Concept

Hemophagocytic lymphohistiocytosis is a hyperinflammatory syndrome characterized by uncontrolled activation of immune cells and mediators. Two diagnostic tools are widely used in clinical practice: the HLH-2004 criteria and the Hscore. Despite their good diagnostic performance, these scores were constructed after a selection of variables based on expert consensus. We propose here a machine learning approach to build a classification model for HLH in a cohort of patients selected by glycosylated ferritin dosage in our tertiary center in Lyon, France. On a dataset of 207 adult patients with 26 variables, our model showed good overall diagnostic performances with a sensitivity of 71.4% and high specificity, and positive and negative predictive values which were 100%, 100%, and 96.9%, respectively. Although generalization is difficult on a selected population, this is the first study to date to provide a machine-learning model for HLH detection. Further studies will be required to improve the machine learning model performances with a large number of HLH cases and with appropriate controls.

Looking into the IL-1 of the storm: are inflammasomes the link between immunothrombosis and hyperinflammation in cytokine storm syndromes?

Inflammasomes and the interleukin (IL)-1 family of cytokines are key mediators of both inflammation and immunothrombosis. Inflammasomes are responsible for the release of the pro-inflammatory cytokines IL-1β and IL-18, as well as releasing tissue factor (TF), a pivotal initiator of the extrinsic coagulation cascade. Uncontrolled production of inflammatory cytokines results in what is known as a "cytokine storm" leading to hyperinflammatory disease. Cytokine storms can complicate a variety of diseases and results in hypercytokinemia, coagulopathies, tissue damage, multiorgan failure, and death. Patients presenting with cytokine storm syndromes have a high mortality rate, driven in part by disseminated intravascular coagulation (DIC). While our knowledge on the factors propagating cytokine storms is increasing, how cytokine storm influences DIC remains unknown, and therefore treatments for diseases, where these aspects are a key feature are limited, with most targeting specific cytokines. Currently, no therapies target the immunothrombosis aspect of hyperinflammatory syndromes. Here we discuss how targeting the inflammasome and pyroptosis may be a novel therapeutic strategy for the treatment of hyperinflammation and its associated pathologies.

Hemiparesis Revealing a Unique Neurological Hemophagocytic Lymphohistiocytosis in a Patient With Griscelli Syndrome Type 2

Griscelli syndrome (GS) is a rare genetic disorder that encompasses three different subtypes (GS type 1 (GS1), GS type 2 (GS2), and GS type 3 (GS3)), in which isolated neurological manifestations without immune system implications are typically seen in GS1, while neurological involvements in GS2 should be attributed to the macrophage and lymphocyte invasion of the central nervous system (CNS), under associated hemophagocytic lymphohistiocytosis (HLH). The presence of the clinical, biological, and hematologic features of HLH help explain the neurological defects that GS2 patients unusually present. In our case report, however, we attempt to highlight an uncommon presentation of GS2 involving a hemiparesis, along which we did not have any clinical or biological features of HLH. We also collect and evaluate similar published cases that feature this problem of explaining the neurological manifestations among GS2 patients.

Haemophagocytic lymphocytic histiocytosis/macrophage activation syndrome with acute inflammatory gastroenteritis

Haemophagocytic lymphocytic histiocytosis (HLH) is a rare, life-threatening condition caused by abnormal activation of cytotoxic T lymphocytes, natural killer cells and macrophages resulting in hypercytokinaemia and immune-mediated injury of multiple organ systems. Secondary HLH occurs in the setting of a malignant, infectious or autoimmune stimulus. Macrophage activation syndrome (MAS) is the term used to describe HLH that develops secondary to rheumatological diseases such as lupus and juvenile idiopathic arthritis, among others. Commonly observed and documented symptoms include fever, organomegaly and lymphadenopathy. Given the potential for multiorgan failure in HLH/MAS, early identification, diagnosis and initiation of treatment is essential. We present a case of secondary HLH/MAS with acute inflammatory gastroenteritis in a middle-aged woman with a history of systemic lupus erythematosus.

A 14-Year-Old Female With Several-Week History of Rash, Worsening Diffuse Arthralgias, and Fevers

Macrophage activation syndrome (MAS) as the initial presentation of systemic juvenile idiopathic arthritis (sJIA) is an uncommon and difficult diagnosis to ascertain. However, it remains critical to establish the diagnosis since MAS is a potentially life-threatening systemic inflammatory condition. Prompt recognition can lead to early initiation of treatment with corticosteroids and overall improved outcomes. Here, we present a case of a 14-year-old female with MAS as the initial manifestation of sJIA.

Evaluation of Macrophage Activation Syndrome in Patients with Systemic Juvenile Idiopathic Arthritis: A Single Center Experience

Objectives. Macrophage activation syndrome (MAS) is a severe complication of systemic juvenile arthritis (sJIA), and early diagnosis is critical for survival. The objective of this study was to evaluate the 2016 MAS classification criteria in a Danish sJIA cohort and to compare different sets of criteria for the early identification of MAS including the HLH-2004 diagnostic guidelines, MS score, and the ferritin/ESR ratio. Methods. Data was extracted from medical charts of 32 patients with sJIA from a single Danish paediatric rheumatology center diagnosed between January 2014 and June 2021. Patients who met the 2016 MAS classification criteria were classified as having MAS. From a receiver operating characteristic (ROC) plot, the area under the curve (AUC) was calculated for the prediction of patients with MAS according to the 2016 MAS classification criteria using either MS score or the ferritin/ESR ratio. Results. Of the cohort, eight (25%) patients were classified as having MAS according to the 2016 MAS classification criteria compared to only three (9.4%) patients fulfilling the HLH-2004 diagnostic guidelines, all of which had recurrent MAS. The ferritin/ESR ratio showed the highest sensitivity (100%) but the lowest specificity (72.2%). In comparison, the MS score had a higher specificity (90.9%) for the identification of MAS according to the 2016 classification criteria. In our cohort, the most optimal cut-off point for the ferritin/ESR ratio was ≥19.4 (sensitivity: 100%, specificity: 72.2%) and ≥ -1.5 for the MS score (sensitivity: 71.4%, specificity: 91.7%), respectively. Conclusion. The 2016 MAS classification criteria were a valuable tool in the discrimination of sJIA with and without MAS. The HLH-2004 diagnostic guidelines showed the lowest sensitivity, ferritin/ESR ratio, and the lowest specificity compared to the MS score where an acceptable high sensitivity and specificity was found.

Macrophage activation syndrome in rheumatic disease: Clinical characteristics and prognosis of 20 adult patients

Objectives

Macrophage activation syndrome (MAS) is a hyperinflammatory condition that is known to be secondary hemophagocytic lymphohistiocytosis (HLH) in patients with rheumatic disease. The aim of study was to evaluate the clinical manifestations and outcomes in patients with MAS with rheumatic disease.

Materials and methods

We performed a retrospective study of 20 adult patients who were diagnosed with MAS from 2012 to 2020. MAS was classified according to the HLH-2004 criteria. Patients’ information, including clinical features, laboratory findings, and treatment regimens, was collected, and the overall survival rate was estimated by the Kaplan–Meier method.

Results

Twenty patients (18 women, 35.6 ± 18.3 years) who met the HLH-2004 criteria also fulfilled the 2016 EULAR/ACR/PRINTO classification criteria for MAS, and HScore was higher than 169 (mean, 241.1). Fourteen patients with systemic lupus erythematosus and 6 patients with adult-onset Still’s disease were included. All patients were treated initially with corticosteroids, and 16 patients required additional immunosuppressants. The overall survival at 3 and 6 months was 75.2% and 64.3%. In survivors, renal impairment was less common (7.7% versus 71.4%, p = 0.007), the levels of AST (364.0 versus 81.0 IU/L, p = 0.019) and LDH (1346.0 versus 343.0IU/L, p = 0.014), and platelet count (90.0 versus 43.0 × 109/L, p = 0.02) were higher in compared to non-survivors. Nine patients had opportunistic infections, five of whom died during admission.

Conclusion

The mortality of patients with MAS associated with rheumatic disease remains high. Renal impairment, levels of AST and LDH, and platelet count might be associated with prognosis.

6-Mercaptopurine and Macrophage Activation Syndrome Case Report and Review of the Literature

Macrophage activation syndrome is a life-threatening syndrome of uncontrolled immune activation with variable clinical presentation making early diagnosis difficult. It is often manifested by the development of multi-organ failure due to systemic inflammatory response. Patients with ulcerative colitis (UC) on purine antimetabolites are at high risk for severe myelosuppression due to the mechanism of thiopurine toxicity which potentially contributes to the development of macrophage activation syndrome. We present a case of a 39-year-old woman with a 2-year history of UC previously treated with 6-mercaptopurine (6-MP) and recent COVID-19 infection, who was admitted to our emergency department for C. difficile infection and subsequently developed macrophage activation syndrome. This case report also raises the question of whether abrupt discontinuation of 6-MP may have contributed to the worsening of the patient's symptoms of underlying hemophagocytic lymphohistiocytosis (HLH) and her rapid deterioration. Both macrophage activation syndrome and COVID-19 infection can produce a large number of pro-inflammatory cytokines termed "cytokine storm," but a pro-inflammatory cytokine panel breakdown helps to differentiate between the two. Our case report emphasizes the importance of close monitoring of patients on purine antimetabolite therapy who present with signs and symptoms of systemic toxicity.

Coronavirus Disease 2019 Infection and Early Diagnosis of Macrophage Activation Syndrome: A Case Report of a 62 year old man

A 62-year-old man presented with a history of fever, headache, anosmia, ageusia, and diarrhea for 9 days. A clinical and epidemiological diagnosis of infection with the novel coronavirus was made. After symptom refractoriness, the second step involves using human intravenous immunoglobulin. Early diagnosis of macrophage activation syndrome (MAS) involves observation of the refractory nature of clinical support treatment associated with biochemical changes to the patient's baseline characteristics, suggesting the relevance of a favorable clinical outcome of weaning from artificial life support when there is an early suspicion of a diagnosis of MAS secondary to coronavirus disease 2019 infection.

The Role of Early Subspeciality Consultation in the Timing of Hemophagocytic Lymphohistiocytosis Diagnosis and Management

OBJECTIVE

The aim of this study was to investigate the relation between timing of subspeciality consult and hemophagocytic lymphohistiocytosis (HLH) consideration, immunosuppression initiation, and in-hospital mortality in patients with HLH.

METHODS

We conducted a medical records review study of patients 18 years or older with definite or probable HLH at Montefiore Medical Center between 2006 and 2019. Earlier subspeciality consultation (rheumatology, hematology, and infectious disease) was defined as consultation in less than or equal to 18 hours from time of admission. Demographic, clinical characteristics, and outcomes were compared between patients with early and later subspecialty consultation.

RESULTS

A total of 28 patients were included. The median age was 40 years, and 61% of patients were male. Infection was identified as a cause of HLH in 13 patients (46%). Fifteen patients (54%) were classified as having an earlier subspeciality consultation with a median time (interquartile range) to HLH consideration of 1.0 day (0.3-4.2 days) compared with 7.9 days (3.1-9.9 days) for the later consultation group (p = 0.002). The median time (interquartile range) to immunosuppression initiation was 4.6 days (1.7-7.8 days) versus 10.9 days (5.1-13.4 days) (p = 0.01), respectively. Five patients (33%) had in-hospital deaths in the early consultation group compared with 7 patients (54%) in later consultation group (p = 0.27). Among the subset of patients who survived to discharge, the 90-day readmission rate was higher in the later consultation group (83% vs 30%, p = 0.12).

CONCLUSIONS

In patients with HLH, earlier subspeciality consultation may play a role in earlier HLH consideration and treatment initiation.

Progressive, refractory macrophage activation syndrome as the initial presentation of anti-MDA5 antibody positive juvenile dermatomyositis: a case report and literature review

BACKGROUND

Macrophage activation syndrome (MAS) is a severe and under-recognized complication of rheumatologic diseases. We describe a patient who presented with rapidly progressive, refractory MAS found to have anti-MDA5 antibody Juvenile Dermatomyositis (JDM) as her underlying rheumatologic diagnosis.

CASE PRESENTATION

We describe a 14-year-old female who at the time of admission had a history of daily fevers for 6 weeks and an unintentional sixteen-pound weight loss. Review of systems was significant for cough, shortness of breath, chest pain, headaches, sore throat, muscle aches, rash, nausea, and loss of appetite. An extensive initial workup revealed findings consistent with an autoimmune process. While awaiting results of her workup she had clinical decompensation with multi-organ system involvement including pancytopenias, interstitial lung disease, hepatitis, cardiac involvement, gastrointestinal distension and pain, feeding intolerance, extensive mucocutaneous candidiasis, and neuropsychiatric decline. Due to her decompensation, significant interstitial lung disease, and likely underlying rheumatologic condition she was started on high dose pulse steroids and mycophenolate. An MRI was performed due to her transaminitis and shoulder pain revealing significant myositis. Intravenous immunoglobulin was then initiated. The myositis antibody panel sent early in her workup was significant for anti-MDA5 and anti-SSA-52 antibodies. Despite high dose pulse steroids, mycophenolate, and IVIG, her disease progressed requiring escalating therapies. Ultimately, she responded with resolution of her MAS as well as significant and steady improvement in her feeding intolerance, interstitial lung disease, cardiac dysfunction, myositis, arthritis, and cutaneous findings.

CONCLUSIONS

JDM in the pediatric patient is rare, as is MAS. In patients with complex rheumatologic conditions and lack of response to treatment, it is important to continually assess the patient's clinical status with MAS in mind, as this may change the treatment approach. Without proper recognition of this complication, patients can have a significant delay in diagnosis leading to life-threatening consequences.

Is COVID-19-associated cytokine storm distinct from non-COVID-19 secondary hemophagocytic lymphohistiocytosis?

Cytokine storm is an umbrella term that describes an inflammatory syndrome characterized by elevated levels of circulating cytokines and hyperactivation of innate and/or adaptive immune cells. One type of cytokine storm is hemophagocytic lymphohistiocytosis (HLH), which can be either primary or secondary. Severe COVID-19-associated pneumonia and acute respiratory distress syndrome (ARDS) can also lead to cytokine storm/cytokine release syndrome (CS/CRS) and, more rarely, meet criteria for the diagnosis of secondary HLH. Here, we review the immunobiology of primary and secondary HLH and examine whether COVID-19-associated CS/CRS can be discriminated from non-COVID-19 secondary HLH. Finally, we review differences in immunobiology between these different entities, which may inform both clinical diagnosis and treatment of patients.

The spectrum of hemophagocytic lymphohistiocytosis: a retrospective study comparing adult macrophage activation syndrome to malignancy-associated hemophagocytic lymphohistiocytosis

Secondary hemophagocytic lymphohistiocytosis (sHLH) is a life-threatening inflammatory syndrome that can be triggered by autoimmune diseases, malignancy, or infection. In rheumatologic patients, sHLH is referred to as macrophage activation syndrome (MAS). Differentiating between triggers is important for prompt treatment and prognosis. Data comparing subsets of sHLH are limited due to the rarity of this disease. We aim to explore differences in clinical features that may differentiate MAS from malignancy-associated HLH (mHLH) patients. We conducted a single-center retrospective study assessing clinical characteristics, laboratory parameters, treatment regimens and outcomes in 34 patients with sHLH over a 16 year period. We compared patients with MAS to those with mHLH. Hepatomegaly was not present in the MAS group but was present in the mHLH group (0 vs. 25%, p = 0.024). MAS patients had on average nearly double the concentration of platelets at 50.0 (IQR: 31.0–78.0 Kµ/L) vs. 29.0 Kµ/L (IQR: 14.0–37.5 Kµ/L), p = 0.003. Soluble IL-2R concentrations were four times lower in the MAS group with a median soluble IL-2R concentration of 6814.5 kU/L (IQR: 2101–2610 kU/L) vs. 27972.0 kU/L (IQR: 12,820–151,650 kU/L), p = 0.010. The MAS group fared better overall than the mHLH group but was not statistically significant (mortality 22 vs. 44%, p = 0.18). MAS and mHLH patients exhibited different laboratory parameters and clinical features, most notably differences in platelet counts, soluble IL-2R concentration and hepatomegaly, which may help differentiate these conditions early in their course.

Macrophage activation syndrome in MDA5 antibody-positive dermatomyositis and COVID-19 infection

Background

Macrophage activation syndrome (MAS) is a rare multiorgan system disorder that may present as a fatal complication of underlying rheumatological disease, including dermatomyositis.

Case presentation

Here, we report the case of a 65-year-old Caucasian female with a history of psoriasis and a recent diagnosis of Coronavirus disease 2019 (COVID-19) who presented with progressive generalized weakness, joint pains, an erythematous rash, shortness of breath, and weight loss. She was ultimately diagnosed with biopsy-confirmed melanoma differentiation-associated protein 5 (MDA5)-positive dermatomyositis complicated by MAS, requiring intravenous immunoglobulin and high-dose methylprednisolone.

Conclusions

This report serves as a clinical reminder of the rare, yet clinically relevant association between MDA5-positive dermatomyositis and MAS, as well as highlights the potential contribution of other immune system activating diseases, such as COVID-19, associated with a cytokine storm and hyperinflammatory state.

Macrophage Activation Led Acute Heart Failure Managed Successfully with Immunosuppression

Macrophage activation leading to multi-organ dysfunction/failure has been described in various hematologic disorders like hemophagocytic lympho-histiocytosis (HLH), also known as macrophage activation syndrome (MAS) and macrophage activation like syndrome (MALS). Congestive heart failure (CHF) appears to be an uncommon manifestation of macrophage activation. This novel entity of macrophage activation-associated cytokine-mediated CHF has not been well reported in the medical literature. We report two young female patients with acute CHF secondary to macrophage activation-associated cytokine storm. An extensive diagnostic workup was negative for other etiologies, such as ischemia, myocarditis, or infections. Their clinical, laboratory, and pathologic findings did not meet the diagnostic criteria for hemophagocytic syndrome (HPS)/MAS. However, both had laboratory and pathologic findings which were consistent with macrophage activation and cytokine storm. One patient met criteria for MALS. Therapeutically, our patients were promptly treated with steroids with or without anti-cytokine therapy with rapid restoration of cardiac function. Macrophage activation-induced disease may not always fulfil the diagnostic criteria for the currently known macrophage activation disorders. We suggest that markers of macrophage activation and cytokine levels should be part of the diagnostic workup in patients with otherwise unexplained acute CHF. Additional research is warranted to further elucidate the underlying mechanism of this disorder.

Prompt Recognition of Hemophagocytic Lymphohistiocytosis in an Afebrile Patient with Lupus and Staphylococcus aureus Bacteremia

Patient: Male, 43-year-old

Final Diagnosis: Hemophagocytic lymphohistiocytosis (HLH)

Symptoms: Acute kidney injury • anorexia • dyspnea • epistaxis • heart murmur • hepatosplenomegaly • murmur • weakness • weight loss

Medication: —

Clinical Procedure: Bone marrow biopsy • CT scan • echocardiography • plasmapharesis • renal biopsy • ultrasonography

Specialty: Hematology • General and Internal Medicine • Nephrology • Pathology • Rheumatology

Macrophage activation syndrome triggered by systemic lupus erythematosus flare: successful treatment with a combination of dexamethasone sodium phosphate, intravenous immunoglobulin, and cyclosporine: a case report

Background

Macrophage activation syndrome is classified as a secondary form of hemophagocytic lymphohistiocytosis. It is a hyperinflammatory complication observed to be comorbid with a variety of autoimmune diseases, including adult-onset Still’s disease and systemic juvenile idiopathic arthritis. Macrophage activation syndrome is less commonly detected in adult patients with systemic lupus erythematosus, which, if untreated, can be fatal, though determining the optimum treatment strategy is still a challenge.

Case presentation

Herein, we report a case of macrophage activation syndrome in a 33-year-old Egyptian female as an unusual complication of a systemic lupus erythematosus flare in adult patients. Our patient was initially treated with a combination of intravenous methylprednisolone pulse therapy and intravenous immunoglobulin therapy, which was followed by a course of oral prednisolone and oral cyclosporine with little response. Switching from oral prednisone to intravenous dexamethasone sodium phosphate showed a more favorable clinical and biochemical response.

Conclusion

Macrophage activation syndrome is less commonly detected in adult patients with systemic lupus erythematosus. Our case demonstrates that dexamethasone sodium phosphate can be a successful alternative treatment for patients with systemic lupus erythematosus complicated by macrophage activation syndrome in whom the response to pulse methylprednisolone was inadequate to manage their illness, proving to be remarkably effective in a relatively short time frame.

From Anti-SARS-CoV-2 Immune Response to the Cytokine Storm via Molecular Mimicry

The aim of this study was to investigate the role of molecular mimicry in the cytokine storms associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Human proteins endowed with anti-inflammatory activity were assembled and analyzed for peptide sharing with the SARS-CoV-2 spike glycoprotein (gp) using public databases. It was found that the SARS-CoV-2 spike gp shares numerous pentapeptides with anti-inflammatory proteins that, when altered, can lead to cytokine storms characterized by diverse disorders such as systemic multiorgan hyperinflammation, macrophage activation syndrome, ferritinemia, endothelial dysfunction, and acute respiratory syndrome. Immunologically, many shared peptides are part of experimentally validated epitopes and are also present in pathogens to which individuals may have been exposed following infections or vaccinal routes and of which the immune system has stored memory. Such an immunologic imprint might trigger powerful anamnestic secondary cross-reactive responses, thus explaining the raging of the cytokine storm that can occur following exposure to SARS-CoV-2. In conclusion, the results support molecular mimicry and the consequent cross-reactivity as a potential mechanism in SARS-CoV-2-induced cytokine storms, and highlight the role of immunological imprinting in determining high-affinity, high-avidity, autoimmune cross-reactions as a pathogenic sequela associated with anti-SARS-CoV-2 vaccines.

Immunomodulation and immunotherapeutics of COVID-19

Severe acute respiratory syndrome coronavirus-2 causes coronavirus disease 2019, a pandemic which was originated from Wuhan city of China. The pandemic has affected millions of people worldwide. The pathogenesis of SARS-CoV-2 is characterized by a cytokine storm in the blood (cytokinemia) and tissues, especially the lungs. One of the major repercussions of this inflammatory process is the endothelial injury-causing intestinal bleeding, coagulopathy, and thromboembolism which result in various sudden and unexpected post-COVID complications including kidney failure, myocardial infarction, or multiorgan failure. In this review, we have summarized the immune responses, biochemical changes, and inflammatory responses in the human body after infection with the SARS-CoV-2 virus. The increased amount of inflammatory cytokines, chemokines, and involvement of complement proteins in inflammatory reaction increase the risk of occurrence of disease.

Etiologies and management of haemophagocytic lymphohistiocytosis: is it time for an updated protocol and targeted treatments?

OBJECTIVE

The objective of this study was to analyse the features, therapeutic approaches, and outcomes for adult patients with haemophagocytic lymphohistiocytosis (HLH) at a single centre.

METHODS

This study was a retrospective chart review of all patients >18 years of age diagnosed with HLH according to HLH-2004 or H-score criteria at Ochsner Medical Center-New Orleans between 2013 and 2019.

RESULTS

A total of 29 patients with HLH met inclusion criteria. A total of 7 patients had an underlying malignancy, 12 had an autoimmune disease, 2 were transplant patients, and 2 had a combination of malignancy, autoimmune disease, or immunodeficiency. A total of 6 patients developed HLH precipitated by infection alone. All 29 patients presented with fever. A total of 28 (97%) patients met H-score criteria, and only 20 (67%) met HLH-2004 criteria. Fifteen patients were treated with the HLH-2004 protocol. Of those treated with the HLH-2004 protocol, 73% (11/15) died, 8% (1/15) had recurrence of HLH, and 20% (3/15) had resolution of HLH. A total of 14 patients were treated with targeted therapy. Of those treated with targeted therapy, 93% (13/14) had resolution of HLH and 1 died. Targeted therapy included pulse steroids, tocilizumab, anakinra, IVIG, CSA, rituximab, and/or CYC in addition to antiviral or antibiotic therapy.

CONCLUSION

Our findings suggested that the rheumatologic patient population responded well to a targeted therapeutic approach and poorly to the HLH-2004 protocol. Whether the poor outcomes found with the use of the HLH-2004 protocol are secondary to the protocol itself or the aggressive nature of malignancy-associated HLH is unclear. Further studies are needed to develop tailored therapeutic regimens.

Hemophagocytic Lymphohistiocytosis

CONTEXT.—

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening disorder of immune regulation that can eventually result in end-organ damage and death. HLH is characterized by uncontrolled activation of cytotoxic T lymphocytes, natural killer cells, and macrophages that can lead to a cytokine storm. The diagnosis of HLH is often challenging due to the diverse clinical manifestations and the presence of several diagnostic mimics. The prognosis is generally poor, warranting rapid diagnosis and aggressive management.

OBJECTIVE.—

To provide a comprehensive review of the pathogenesis, clinical features, diagnosis, and management of HLH.

DATA SOURCES.—

Peer-reviewed literature.

CONCLUSIONS.—

HLH is a condition where a complete understanding of the pathogenesis, early diagnosis, and proper management has an important role in determining patient outcome. Genetic mutations causing impairment in the function of cytotoxic T lymphocytes and natural killer cells have been identified as the root cause of familial HLH; however, the specific pathogenesis of acquired HLH is unclear. The HLH-2004 protocol used in the diagnosis of HLH was originally developed for the pediatric population. The HLH-2004 protocol still forms the basis of the diagnosis of HLH in adults, although its use in adults has not been formally validated yet. Treatment of HLH is primarily based on the HLH-94 protocol, which involves suppressing the inflammatory response, but the treatment needs to be modified in adults depending on the underlying cause and comorbidities.

The cytokine storms of COVID-19, H1N1 influenza, CRS and MAS compared. Can one sized treatment fit all?

An analysis of published data appertaining to the cytokine storms of COVID-19, H1N1 influenza, cytokine release syndrome (CRS), and macrophage activation syndrome (MAS) reveals many common immunological and biochemical abnormalities. These include evidence of a hyperactive coagulation system with elevated D-dimer and ferritin levels, disseminated intravascular coagulopathy (DIC) and microthrombi coupled with an activated and highly permeable vascular endothelium. Common immune abnormalities include progressive hypercytokinemia with elevated levels of TNF-α, interleukin (IL)-6, and IL-1β, proinflammatory chemokines, activated macrophages and increased levels of nuclear factor kappa beta (NFκB). Inflammasome activation and release of damage associated molecular patterns (DAMPs) is common to COVID-19, H1N1, and MAS but does not appear to be a feature of CRS. Elevated levels of IL-18 are detected in patients with COVID-19 and MAS but have not been reported in patients with H1N1 influenza and CRS. Elevated interferon-γ is common to H1N1, MAS, and CRS but levels of this molecule appear to be depressed in patients with COVID-19. CD4+ T, CD8+ and NK lymphocytes are involved in the pathophysiology of CRS, MAS, and possibly H1N1 but are reduced in number and dysfunctional in COVID-19. Additional elements underpinning the pathophysiology of cytokine storms include Inflammasome activity and DAMPs. Treatment with anakinra may theoretically offer an avenue to positively manipulate the range of biochemical and immune abnormalities reported in COVID-19 and thought to underpin the pathophysiology of cytokine storms beyond those manipulated via the use of, canakinumab, Jak inhibitors or tocilizumab. Thus, despite the relative success of tocilizumab in reducing mortality in COVID-19 patients already on dexamethasone and promising results with Baricitinib, the combination of anakinra in combination with dexamethasone offers the theoretical prospect of further improvements in patient survival. However, there is currently an absence of trial of evidence in favour or contravening this proposition. Accordingly, a large well powered blinded prospective randomised controlled trial (RCT) to test this hypothesis is recommended.

Sudden Hypotension and Increased Serum Interferon-γ and Interleukin-10 Predict Early Macrophage Activation Syndrome in Patients with Systemic Juvenile Idiopathic Arthritis

OBJECTIVE

To identify clinical and laboratory predictors for early macrophage activation syndrome (MAS) associated with systemic juvenile idiopathic arthritis (sJIA).

STUDY DESIGN

This is a retrospective cohort study of 149 patients with sJIA, of whom 27 had 31 episodes of MAS. We evaluated the clinical and laboratory features of patients with sJIA and MAS and compared them with those without MAS. We focused our analysis on the overall process of MAS development, especially MAS onset.

RESULTS

As shown in previous studies, we found a high percentage of fever, absence of arthritis, and central nervous system dysfunction at MAS onset in our study cohort. We also found that 35% of patients with MAS had hypotension although not shock, and 22.6% of patients with MAS had gastrointestinal involvement at MAS onset. Compared with patients with MAS without hypotension, patients with MAS and hypotension had greater rates of admission to the intensive care unit; presented with more arthritis, serositis, pneumonia, and gastrointestinal involvement; and had greater white blood cell and absolute neutrophil counts and serum bilirubin levels and lower serum total protein. We confirmed laboratory markers such as platelet counts, lactate dehydrogenase, and aspartate aminotransferase can help to identify early MAS and that ferritin/erythrocyte sedimentation rate ratio of approximately 20.0 had a high diagnostic sensitivity and specificity for MAS. In addition, we discovered that the combination of interferon-γ >17.1 pg/mL and interleukin-10 >7.8 pg/mL appeared to be a good cytokine pattern for the recognition of MAS onset.

CONCLUSIONS

Sudden hypotension, elevated ferritin/erythrocyte sedimentation rate ratio, and the cytokine pattern of significantly increased interferon-γ and interleukin-10 levels are important markers for early identification of MAS in addition to the traditional characteristics of sJIA-associated MAS.

Dynamics of host immune responses to SARS-CoV-2

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the most recent global health threat, is spreading throughout the world with worrisome speed, and the current wave of coronavirus disease 2019 (COVID-19) seems to have no mercy. While this mysterious virus challenges our ability to control viral infections, our opportunities to control the COVID-19 pandemic are gradually fading. Currently, pandemic management relies on preventive interventions. Although prevention is a good strategy to mitigate SARS-CoV-2 transmission, it still cannot be considered an absolute solution to eliminate this pandemic. Currently, developing a potent immunity against this viral infection seems to be the most promising strategy to drive down this ongoing global tragedy. However, with the emergence of new challenges in the context of immune responses to COVID-19, the road to control this devastating pandemic seems bumpier; thus, it is pivotal to characterize the dynamics of host immune responses to COVID-19, in order to develop efficient prophylactic and therapeutic tools. This begs the question of whether the effector mechanisms of the immune system are indeed potent or a possible contributing factor to developing more severe and lethal forms of COVID-19. In this review, the possible role of the immunopathologic phenomena including antibody-dependent enhancement, cytokine storm, and original antigenic sin in severity and mortality of COVID-19 will be discussed.

Bidirectional association between systemic lupus erythematosus and macrophage activation syndrome: a nationwide population-based study

OBJECTIVES

To determine the bidirectional relationship between macrophage activation syndrome (MAS) and systemic lupus erythematosus (SLE).

METHODS

Using the 1997-2013 Taiwan's National Health Insurance Research Database, we identified patients with newly diagnosed SLE from 2001 to 2013 from the whole beneficiaries and selected individuals without SLE from a one-million representative population. Propensity score (PS) matching was performed to balance incident SLE patients and individuals without SLE according to age, sex, comorbidities and medical utilization. The association between a history of MAS and SLE was studied using conditional logistic regression analysis shown as adjusted odds ratio (aOR). The risk of MAS associated with SLE was analyzed using Cox proportional regression analysis shown as hazard ratio (aHR), and we conducted a sensitivity analysis using various definitions of MAS.

RESULTS

We finally included 10,481 SLE patients and 20,962 PS-matched (1:2) non-SLE individuals. The correlation between a history of MAS and SLE did not reach statistical significance after adjustment for potential confounders (aOR, 1.18; 95% confidence interval, 0.80-1.75) in the age/sex-matched populations. In the 1:2 PS-matched populations, the risk of MAS markedly increased in patients with SLE (aHR, 7.18; 95% confidence interval, 4.97-10.36). Other risk factors for MAS included female, age ≥ 65 years, low income, a history of inflammatory bowel disease, and MAS history.

CONCLUSION

This nationwide, population-based study revealed that a history of MAS was not significantly associated with SLE risk. However, the risk of MAS was markedly associated with SLE and history of MAS.

Efficacy of Tocilizumab Therapy in Different Subtypes of COVID-19 Cytokine Storm Syndrome

Background: Cytokine storm in COVID-19 is heterogenous. There are at least three subtypes: cytokine release syndrome (CRS), macrophage activation syndrome (MAS), and sepsis. Methods: A retrospective study comprising 276 patients with SARS-CoV-2 pneumonia. All patients were tested for ferritin, interleukin-6, D-Dimer, fibrinogen, calcitonin, and C-reactive protein. According to the diagnostic criteria, three groups of patients with different subtypes of cytokine storm syndrome were identified: MAS, CRS or sepsis. In the MAS and CRS groups, treatment results were assessed depending on whether or not tocilizumab was used. Results: MAS was diagnosed in 9.1% of the patients examined, CRS in 81.8%, and sepsis in 9.1%. Median serum ferritin in patients with MAS was significantly higher (5894 vs. 984 vs. 957 ng/mL, p < 0.001) than in those with CRS or sepsis. Hypofibrinogenemia and pancytopenia were also observed in MAS patients. In CRS patients, a higher mortality rate was observed among those who received tocilizumab, 21 vs. 10 patients (p = 0.043), RR = 2.1 (95% CI 1.0–4.3). In MAS patients, tocilizumab decreased the mortality, 13 vs. 6 patients (p = 0.013), RR = 0.50 (95% CI 0.25–0.99). Conclusions: Tocilizumab therapy in patients with COVID-19 and CRS was associated with increased mortality, while in MAS patients, it contributed to reduced mortality.

Ferritin, fever, and frequent visits: Hyperferritinemic syndromes in the emergency department

Fever of unknown origin (FUO) is defined as persistent fevers without an identifiable cause despite extensive medical workup. Emergency physicians caring for patients reporting a persistent, nonspecific, febrile illness should carefully consider potentially serious non-infectious causes of FUO. We present a case of a 35-year-old man who presented to the emergency department (ED) three times over a 10-day period for persistent febrile illness and was ultimately diagnosed with Adult-Onset Still's Disease (AOSD) after a serum ferritin level was found to be over 42,000 μg/L. AOSD, along with macrophage activation syndrome, catastrophic antiphospholipid syndrome, and septic shock comprise the four hyperferritinemic syndromes. These are potentially life-threatening febrile illnesses that characteristically present with elevated ferritin levels. In this article, we highlight the value of a serum ferritin level in the workup of a patient with prolonged febrile illness and its utility in facilitating early diagnosis and prompt treatment of hyperferritinemic syndromes in the ED.