Autoimmune myelofibrosis: an update on morphologic features in 29 cases and review of the literature

SOHO State of the Art Updates and Next Questions | Diagnosis, Outcomes, and Management of Prefibrotic Myelofibrosis

Prefibrotic primary myelofibrosis (prefibrotic PMF) is a myeloproliferative neoplasm with distinct characteristics comprising histopathological and clinico-biological parameters. It is classified as a subtype of primary myelofibrosis. In clinical practice, it is essential to correctly distinguish prefibrotic PMF from essential thrombocythemia especially but also overt PMF besides other myeloid neoplasms. Risk stratification and survival outcomes for prefibrotic PMF are worse than that of ET but better than that of overt PMF. Rates of progression to overt PMF and blast phase disease are also higher for prefibrotic PMF than ET. In this review we first discuss the historical context to the evolution of prefibrotic PMF as an entity, its presenting features and diagnostic criteria. We emphasize the differences between prefibrotic PMF, ET, and overt PMF with regards to presenting features and disease outcomes including thrombohemorrhagic events and progression to fibrotic and blast phase disease. Next, we discuss the risk stratification models and contextualize these in the setting of clinical management. We share our view of personalizing treatment to address unique patient needs in the context of currently available management options. Lastly, we discuss areas of critical need in clinical research and speculate on the possibility of future disease course modifying therapies in prefibrotic PMF.

Long-lasting severe anemia following treatment with natalizumab for relapsing-remitting multiple sclerosis: a case report

BACKGROUND

Natalizumab is a monoclonal antibody used to treat patients with relapsing-remitting multiple sclerosis. Anemia is a recognized side effect, but it is usually mild and of a short duration when natalizumab is stopped. Here, we describe a case of a young woman with severe and especially long lasting anemia associated with treatment with natalizumab, persisting up to a year after treatment was stopped.

CASE PRESENTATION

A 24 year-old Caucasian woman with relapsing-remitting multiple sclerosis developed severe transfusion dependent anemia after 27 infusions with natalizumab, which was her first and only treatment for her multiple sclerosis. Extensive hematologic diagnostics did not reveal any malignant cause or any other plausible non-malignant cause for her anemia. The bone marrow was found to be hypercellular, with a maturation arrest of the erythropoiesis and with grade 1-2 fibrosis. No specific treatment for the anemia was given. The hemoglobin level showed signs of spontaneous increase after nearly one year after natalizumab was discontinued.

CONCLUSION

Severe anemia can be caused by treatment with natalizumab. This case adds information to the few other similar reported cases, demonstrating the potential duration of the anemia, as well as detailed description of hematologic findings. The mechanism is most likely due to inhibition of α4 subunit of the α4β1-integrin, which is present on both lymphocytes and erythroid precursor cells.

Autoimmune myelofibrosis: A Mayo Clinic series of 22 patients

We describe the clinical phenotype, management strategies and outcomes of 22 patients with autoimmune myelofibrosis (AIMF); median age: 45 years; 77% females; 83% with autoimmune disease, pancytopenia in 32% and transfusion-requiring anaemia in 59%. All informative cases were negative for JAK2 (n = 18) and CALR/MPL mutations (n = 12). Fourteen of nineteen (74%) evaluable patients achieved complete response (CR) based on the resolution of cytopenias. First-line treatments included steroids +/- immunosuppressive agents, cyclosporin and mycophenolate with CR in 7 of 13 (54%), 1 of 2 (50%) and 1 of 2 (50%) respectively. Rituximab salvage therapy yielded CR in 4 of 5 (80%) cases. The current study provides information on steroid-sparing treatments for AIMF.

An overlooked mimic? Autoimmune myelofibrosis-A scoping review of the literature

BACKGROUND AND OBJECTIVES

Autoimmune myelofibrosis (AIMF) is a rare cause of bone marrow fibrosis (BMF) occurring in the presence or absence of a defined autoimmune disease (secondary or primary AIMF, sAIMF/pAIMF, respectively). Unlike primary myelofibrosis (PMF), AIMF responds well to immunosuppressive therapy with a benign clinical course. Diagnostic criteria for AIMF in opposition to PMF have been lacking, though recent work has helped better characterise molecular and pathological features of AIMF, improving diagnostic precision.

METHODS

Using a modern clinical and pathophysiological understanding of AIMF, we apply scoping review methodology and rigorous case-criteria to retrospectively analyse the case literature. We examine its patient-population, describing patient-associated factors, presentation, bone marrow pathology, genetics, treatment and outcomes.

RESULTS

Fifty-five studies were identified, describing 139 AIMF patients. Patients were mostly young females (~4:1 ratio female:male, median age 40.8 years) and typically presented with cytopenias. Splenomegaly was rare. sAIMF was more common than pAIMF (~3:1 ratio), and most cases responded well to immunosuppressive therapy.

CONCLUSIONS

Our results strengthen the emerging picture of AIMF's patient population, natural history and response to treatment. Further work should continue to use reproducible diagnostic criteria, and explore AIMF's pathophysiology, response to different therapies, and sequelae over larger timescales, as well as differences between pAIMF, sAIMF and PMF.

Nestin+ Mesenchymal Stromal Cells Fibrotic Transition Mediated by CD169+ Macrophages in Bone Marrow Chronic Graft-versus-Host Disease

Chronic graft-versus-host disease (cGVHD) involves multiple organs, but little is known about bone marrow (BM) alterations caused by cGVHD. In mice and humans, we found that cGVHD is associated with BM fibrosis resulting in T cell infiltration, IgG deposition, and hematopoietic dysfunction. Macrophages and Nestin+ mesenchymal stromal cells (MSCs) participated in the process of BM fibrosis during BM cGVHD development. BM macrophage numbers were significantly increased in mice and humans with BM fibrosis associated with cGVHD. Amplified macrophages produced TGF-β1, which recruited Nestin+ MSCs forming clusters, and Nestin+ MSCs later differentiated into fibroblasts, a process mediated by increased TGF-β/Smad signaling. TLR4/MyD88-mediated activation of endoplasmic reticulum (ER) stress in macrophages is associated with fibrosis by increasing Nestin+ MSC migration and differentiation into fibroblasts. Depletion of macrophages by clodronate-containing liposomes and inhibition of ER stress by 4-phenylbutyric acid reversed BM fibrosis by inhibiting fibroblast differentiation. These studies provide insights into the pathogenesis of BM fibrosis during cGVHD development.

Reversible myelofibrosis secondary to systemic lupus erythematosus

Pancytopenia due to systemic lupus erythematosus (SLE) is rarely reported, and among those reported, it is mostly due to immunologically mediated cell destruction. Pancytopenia due to bone marrow fibrosis secondary to SLE is an extremely rare entity. Myelofibrosis secondary to SLE per se is reported only in 21 cases in the literature. Ours probably is the 22nd case report on SLE with myelofibrosis. Primary presentation of SLE with bleeding manifestation is also a rare phenomenon. Partial to complete regression of myelofibrosis is noted following treatment in secondary myelofibrosis caused by SLE. We report a case of a woman in her late 40s who presented to us with bleeding manifestations of petechial rash and menorrhagia, which on further evaluation showed pancytopenia due to myelofibrosis secondary to SLE. Our case underlines multiple features like primary bleeding manifestation and regression of myelofibrosis following treatment which is rarely reported in association with SLE.

Autoimmune Myelofibrosis in a 12-Year-old Male With Monosomy 7, Systemic Lupus Erythematous and Lupus Nephritis: A Case Report and Review of the Literature

Complete or partial loss of chromosome 7 is a common and well-known cytogenetic abnormality associated with preleukemic myelodysplasia and myeloid leukemia but not with autoimmune myelofibrosis. Detection of this molecular change represents poor prognosis. When malignant transformation occurs, the condition tends to be chemotherapy-resistant requiring haematopoietic stem cell transplantation (HSCT) to obtain a cure. Disappearance after immunosuppressive therapy has been documented in children with hematological disorders but not in association with cyclophosphamide and systemic lupus erythematous.We present the interesting case of a 12-year-old male with monosomy 7, systemic lupus erythematous, and lupus nephritis with the resolution of the monosomy 7 and autoimmune myelofibrosis after treatment with cyclophosphamide, along with a review of the literature.

Improvement in Primary Autoimmune Myelofibrosis Following a Short Course of Steroids and Intravenous Immunoglobulins

Bone marrow fibrosis (BMF) is a histopathological finding appreciated in a multitude of conditions such as myeloproliferative diseases and malignant neoplasms, along with autoimmune disorders. Autoimmune myelofibrosis (AIMF) is a particularly uncommon etiology of benign BMF. AIMF may be primary with serologic evidence of autoantibodies or secondary to an underlying autoimmune disease. The authors aim to emphasize the importance of distinguishing between primary versus secondary causes owing to significant prognostic and therapeutic discrepancies and in hopes of expediting the diagnostic journey. Research has recommended a treatment strategy of high-dose steroids followed by a steroid taper. However, our patient responded positively to a short course of high-dose steroids and intravenous immunoglobulins (IVIG) as evidenced by an improvement in cytopenias and bone marrow fibrosis grading. This outcome warrants further research on the necessity of steroid tapers in AIMF.

Managing connective tissue disease: how to select and facilitate successful transplantation

PURPOSE OF REVIEW

Lung transplant (LTx) evaluation and selection of candidates with connective tissue disease (CTD) remains controversial and varies between centers, and the optimal candidate selection is still controversial.

RECENT FINDINGS

Recent United States and European publications have reported reasonable short-term and long-term LTx outcomes in patients with CTD to other lung fibrosis patients without CTD. This article discusses the recently published International Society for Heart and Lung Transplantation (ISHLT) consensus document recommendations to evaluate and select CTD candidates, the importance of early referral, posttransplant management, and the involvement of a multidisciplinary team.

SUMMARY

Future standardized practices among centers adapting the 2021 ISHLT consensus recommendations to evaluate and select CTD candidates will allow risk stratification, determine the best candidates, and facilitate the most successful long-term LTx outcomes.

How I Diagnose Primary Myelofibrosis

OBJECTIVES

Primary myelofibrosis (PMF) is a BCR/ABL1-negative myeloproliferative neoplasm (MPN) with a shorter overall survival and a higher leukemic transformation than other BCR/ABL1-negative MPNs. Diagnosis of PMF can be challenging given its clinical, morphologic, molecular overlap with other myeloid neoplasms also associated with myelofibrosis, and reactive conditions.

METHODS

We summarize and discuss the clinical, morphologic, and molecular features useful for diagnosing PMF as well as salient features helpful in distinguishing PMF from myelodysplastic syndrome with associated fibrosis and autoimmune myelofibrosis using a case-based approach.

RESULTS

PMF in both its prefibrotic and fibrotic stages, the latter characterized by reticulin/collagen marrow fibrosis, is characterized by a proliferation of predominantly abnormal megakaryocytes and granulocytes in the bone marrow. Driver mutations in   JAK2, CALR, or MPLare seen in approximately 90% of PMF cases. In triple-negative cases, the presence of cytogenetic abnormalities and other somatic mutations identified by next-generation sequencing can help establish a diagnosis of PMF in the appropriate clinical and morphologic context.

CONCLUSIONS

Given the significant difference in prognosis and treatment, integration of clinical, morphological, and molecular/genetic findings is essential in distinguishing PMF from other etiologies that can demonstrate myelofibrosis.

A Practical Perspective of the Hematologic Manifestations of Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic inflammatory disease with an unknown etiology that can affect any organ or system of the human body. Hematological, renal, or central nervous system manifestations in these patients result in great morbidity because high doses of glucocorticoids, cytotoxic medications, or biological drugs are required to control these manifestations. It is noteworthy that hematological involvement predominates during the first years of the disease and tends to last over time, with the premise that it may be the initial manifestation of the disease. Clear examples of this are the cases of hemolytic anemia and immune thrombocytopenia that can be initially classified as idiopathic or primary to be later classified as secondary when associated with infections, medications, neoplasms, or autoimmune diseases. The spectrum of hematologic manifestations in SLE is very broad, including lymphopenia, anemia, thrombocytopenia, or pancytopenia. In some cases, lymphadenopathy and splenomegaly are also identified. The vast majority of these manifestations denote high disease activity. However, many of these alterations have a multifactorial cause that must be taken into account to adopt a more complete therapeutic approach. The objective of this review is to characterize in detail the hematological manifestations of SLE to offer clinicians a practical vision of its diagnosis and treatment.

Understanding Aberrant Signaling to Elude Therapy Escape Mechanisms in Myeloproliferative Neoplasms

Aberrant signaling in myeloproliferative neoplasms may arise from alterations in genes coding for signal transduction proteins or epigenetic regulators. Both mutated and normal cells cooperate, altering fragile balances in bone marrow niches and fueling persistent inflammation through paracrine or systemic signals. Despite the hopes placed in targeted therapies, myeloid proliferative neoplasms remain incurable diseases in patients not eligible for stem cell transplantation. Due to the emergence of drug resistance, patient management is often very difficult in the long term. Unexpected connections among signal transduction pathways highlighted in neoplastic cells suggest new strategies to overcome neoplastic cell adaptation.

Pediatric immune myelofibrosis (PedIMF) as a novel and distinct clinical pathological entity

Myelofibrosis is a rare myeloproliferative disorder. The detailed descriptions of myelofibrosis in children and adolescents is limited to a few case series and case reports describing fewer than 100 patients, thus suggesting the extreme rarity of this condition prior to adulthood. Though pediatric patients rarely present the typical features and outcomes usually observed in older people, pediatric myelofibrosis is not considered an independent entity. Here we aim to describe patients with pediatric myelofibrosis, showing different clinical and pathological features when compared to the World Health Organization 2016 Primary Myelofibrosis classification. We retrospectively collected and analyzed 14 consecutive pediatric myelofibrosis diagnosed in our Pediatric hematology outpatient clinic over a six-year period. According to clinical data and bone marrow biopsy findings, patients were classified into three subgroups: adult-like myelofibrosis, pediatric immune myelofibrosis, idiopathic myelofibrosis. Pediatric Immune Myelofibrosis was the predominant subgroup in our cohort (7/14). Pediatric Immune Myelofibrosis is characterized by peculiar bone marrow features (i.e., T lymphocyte infiltration) and a milder course compared to the other patients Pediatric Immune Myelofibrosis is a novel and distinct pathological entity. We suggest to carefully consider Pediatric Immune Myelofibrosis in case of bone marrow biopsies showing myelofibrosis that do not fulfill WHO criteria.

ISHLT consensus document on lung transplantation in patients with connective tissue disease: Part I: Epidemiology, assessment of extrapulmonary conditions, candidate evaluation, selection criteria, and pathology statements

Patients with connective tissue disease (CTD) and advanced lung disease are often considered suboptimal candidates for lung transplantation (LTx) due to their underlying medical complexity and potential surgical risk. There is substantial variability across LTx centers regarding the evaluation and listing of these patients. The International Society for Heart and Lung Transplantation-supported consensus document on lung transplantation in patients with CTD standardization aims to clarify definitions of each disease state included under the term CTD, to describe the extrapulmonary manifestations of each disease requiring consideration before transplantation, and to outline the absolute contraindications to transplantation allowing risk stratification during the evaluation and selection of candidates for LTx.

AUTOIMMUNE MYELOFIBROSIS ASSOCIATED WITH SYSTEMIC LUPUS ERYTHEMATOSUS: EXCEPTIONALLY RARE OR UNDERRECOGNIZED?

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease which may involve several organs or organ systems. SLE may also have hematological as well as joint, kidney, and central nervous system involvements. Hematological abnormalities such as anemia, leukopenia, thrombocytopenia, and autoimmune hemolytic anemia are the best-known and most common hematological findings detected in SLE patients which are included in the classification criteria for SLE.  Autoimmune myelofibrosis (AIMF) refers to bone marrow (BM) fibrosis (myelofibrosis) that develops in an autoimmune setting. Myelofibrosis is not among the SLE classification criteria and it is also not well-known. Current reports in the literature on SLE-associated AIMF are mostly restricted to case reports or reviews of such case reports. The occurrence of BM fibrosis in SLE patients has been explored merely in few studies which concluded that myelofibrosis is a rare symptom of SLE. Herein, we propose the hypothesis that SLE-associated AIMF is not rare and, on the contrary, it can indeed be more frequent than what is known or expected.

Immunoglobulin G4-Related Disease Accompanied by Primary Myelofibrosis: Case Report

Immunoglobulin G4-related disease (IgG4-RD) is a heterogeneous autoimmune fibrosing disorder that presents common pathologic features but with unclear etiology. We report a rare case of IgG4-RD accompanied by primary myelofibrosis that eventually transformed into acute myeloid leukemia. A 50-year-old woman suffered from progressive lacrimal and parotid gland enlargement, diaphoresis, and rapid weight loss. Important clinical findings included remarkable leukocytosis, hyperglobulinemia, and splenomegaly. IgG4-RD was confirmed by salivary gland biopsy. Meanwhile, myelofibrosis was diagnosed according to histopathological findings of bone marrow and genetic mutation test of peripheral blood. The patient was on corticosteroid treatment. However, she developed into acute myeloid leukemia (AML) in the 8th month of follow-up. Our case suggested that myeloproliferative neoplasm (MPN) may co-occur with IgG4-RD. Bone morrow aspiration and genetic tests are helpful for throughout evaluation. An active search for hematological malignancies is warranted at diagnosis and during follow-up for patients who present with unexplained leukocytosis, pancytopenia, splenomegaly, or weight loss.

Important Pathologic Considerations for Establishing the Diagnosis of Myelofibrosis

Diagnostic criteria for primary myelofibrosis as defined by the 2017 revised World Health Organization (WHO) classification system incorporate clinical and laboratory findings, including driver mutational status (JAK2, MPL, CALR. and triple negative). The WHO emphasized the role of histopathology in making an accurate diagnosis of primary myelofibrosis and successfully incorporated a fibrosis scoring system and scoring schemas for collagen fibrosis and osteosclerosis. These steps represent a significant addition to the standardization of myelofibrosis evaluation and minimize the risk for misdiagnosis. This article reviews important pathologic considerations along with highlights of potentially relevant pitfalls relevant to histopathological diagnosis of myelofibrosis.

Autoimmune myelofibrosis associated with systemic lupus erythematosus: a case report

A 66-year-old woman presented with severe anaemia, thrombocytopenia and lymphopenia. The bone marrow biopsy demonstrated hypocellular marrow with myelofibrosis (MF); there was no evidence of malignancy, but infiltration of peripheral T and B cells were noticed. Magnetic resonance imaging (MRI) revealed that bone marrow of the spine exhibited low signal intensity (SI) with spotty high SI in T1- and T2-weighted images. Because there was evidence of autoimmune abnormality, she had fulfilled the classification criteria for systemic lupus erythematosus (SLE). She was diagnosed with autoimmune myelofibrosis (AIMF) associated with SLE and was treated with corticosteroid. Cytopenia improved after 1 month of corticosteroid therapy. A repeated bone marrow biopsy demonstrated that cellularity had increased and that the amount of reticulin fibre had reduced after treatment. Compared with primary MF, AIMF has generally a favourable prognosis and is often associated with autoimmune diseases, especially SLE. Bone marrow biopsy, but not aspiration, was useful for diagnosing bone marrow fibrosis. Although the association between SLE and MF has been rarely reported, we should pay attention to MF as a possible cause of pancytopenia.

Autoimmune Myelofibrosis in Sjögren's Syndrome: Report of a Case

Patient: Male, 49-year-old

Final Diagnosis: Autoimmune myelofibrosis

Symptoms: Bleeding

Medication:—

Clinical Procedure: Bone marrow biopsy

Specialty: Hematology

Bone marrow fibrosis, sequence variant of asxl1, and Sjögren syndrome: A case report

Only proven pathogenic mutations associated with myeloid neoplasms are key to establish the clonal nature of the bone marrow fibrosis. In cases with genetic variants of uncertain meaning, the clinical picture may be required to rule out secondary causes.

Clinical features of precursor-targeted immune-mediated anemia in dogs: 66 cases (2004-2013)

OBJECTIVE

To characterize the clinical features of dogs with precursor-targeted immune-mediated anemia (PIMA).

ANIMALS

66 dogs with PIMA.

PROCEDURES

Electronic record databases of a teaching hospital were searched to identify dogs with a diagnosis of nonregenerative anemia between 2004 and 2013. Inclusion criteria included persistent nonregenerative anemia (Hct ≤ 30% and reticulocyte count < 76,000 reticulocytes/μL), cytologic findings supportive of ineffective bone marrow erythropoiesis, and absence of underlying disease. Information regarding clinical signs, clinicopathologic findings, treatment, and outcome was extracted from records of eligible dogs. A regenerative response was defined as a reticulocyte count > 76,000 reticulocytes/μL or sustained increase in Hct of > 5%. Remission was defined as a stable Hct ≥ 35%.

RESULTS

The median Hct was 13%, and reticulocyte count was 17,900 reticulocytes/μL. Rubriphagocytosis was identified in bone marrow aspirate samples from 61 of 66 dogs. Collagen myelofibrosis was detected in bone marrow biopsy specimens obtained from 31 of 63 dogs. Immune-mediated targeting of mature erythrocytes was uncommon. All dogs received immunosuppressive therapy. Fifty-five dogs developed a regenerative response at a median of 29 days, and 40 of those dogs went into remission at a median of 59 days after PIMA diagnosis. Thromboembolic events were confirmed for 9 dogs and were associated with a decreased survival time. Median survival time was 913 days for all dogs.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that most dogs with PIMA responded to prolonged immunosuppressive therapy. Studies to determine optimal immunosuppressive and thromboprophylactic protocols for dogs with PIMA are warranted.

Primary autoimmune myelofibrosis: A case report in a child

Autoimmune myelofibrosis (AIMF) is an uncommon cause of myelofibrosis associated with favorable outcome. Primary AIMF, AIMF without a known systemic autoimmune disorder, has been described in adults, but never in children. Here, we present, for the first time, an apparent case of primary AIMF in a 15‐year‐old boy admitted with profound hypoproliferative anemia.

For the first time, we describe a pediatric case of primary autoimmune myelofibrosis presented to the emergency room with profound hypoproliferative, low reticulocyte count, anemia.

A provider's guide to primary myelofibrosis: pathophysiology, diagnosis, and management

Although understanding of the pathogenesis and molecular biology of primary myelofibrosis continues to improve, treatment options are limited, and several biological features remain unexplained. With an appropriate clinical history, exam, laboratory evaluation, and bone marrow biopsy, the diagnosis can often be established. Recent studies have better characterized prognostic factors and driver mutations in myelofibrosis, facilitated by use of next-generation sequencing. These advances have facilitated development of a management strategy that is based on both risk factors and clinical phenotype. For low-risk patients, treatment will depend on symptom severity. For patients with higher-risk disease, several treatments are available including JAK inhibitors, allogeneic hematopoietic stem cell transplant, and clinical trials using novel molecularly targeted therapies and rational drug combinations. In this review, we outline what is known about the disease pathogenesis, discuss an approach to reaching the diagnosis, review the prognosis of myelofibrosis, and detail current therapeutic strategies.

Cytokines frequently implicated in myeloproliferative neoplasms

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MPN is a chronic inflammation-driven tumor model.

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Many cytokines are involved in pathogenesis and progression of MPN.

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IL-1β, TNF-α, IL-6, IL-8, VEGF, PDGF, TGF-β and IFNs are critical in MPN.

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Cytokine directed therapy could be an alternative treatment for MPN in future.

Classical myeloproliferative neoplasms (MPN) include polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). MPN has been defined as a chronic inflammation-driven tumor model. It is clear that there is a close link between chronic inflammation and MPN pathogenesis. Several studies have demonstrated cytokine profiles in MPN patients. Other studies have used cell lines or animal models aiming to clarify the underlying mechanism of cytokines in the pathogenesis of MPN. However, important questions remain: (1) among all these cytokines, which are more predictive? and (2) which are more critical? In this review, we summarize cytokines that have been investigated in MPN and highlight several cytokines that may be more significant in MPN. We suggest that cytokines are more critical in PMF than PV or ET. These cytokines include IL-1β, TNF-α, IL-6, IL-8, VEGF, PDGF, IFNs and TGF-β, all of which should be more closely investigated in MPN. Based on our extensive literature search, several key factors have emerged in our understanding of MPN: first, TNF-α could correlate with MPN progression including PMF, PV and ET. IL-1β plays a role in PMF progression, while it showed no relation with PV or ET. Second, IL-8 could be a prognostic factor for PMF, and IL-6 could be important for MPN progression. Third, VEGF and PDGF play an indirect role in MPN development and their inhibitors could be effective. Fourth, different subtypes of IFNs could have different effects in MPN. Finally, TGF-β is closely linked to MF, although the data are inconsistent. Agents that have targeted these cytokines described above are already in clinical trials, and some of them have even been used to treat MPN patients. Taken together, it will be critical to continue to investigate the precise role of these cytokines in the pathogenesis and progression of MPN.

Autoimmune-Associated Hemophagocytosis and Myelofibrosis in a Newly Diagnosed Lupus Patient: Case Report and Literature Review

Bone marrow abnormalities in SLE are now becoming increasingly recognized, suggesting that the bone marrow may also be an important site of target organ damage. In this study, we present a rare case of concurrent autoimmune hemophagocytic syndrome and autoimmune myelofibrosis, potentially life-threatening conditions, in a newly diagnosed SLE patient. We report a case of a 30-year-old Filipino woman who presented with a one-year history of fever, constitutional symptoms, exertional dyspnea, joint pains, and alopecia and physical examination findings of fever, facial flushing, cervical lymphadenopathies, and knee joint effusions. Laboratory workup revealed pancytopenia with leukoerythroblastosis, elevated ESR, increased serum levels of transaminases, elevated CRP and LDH, hyperferritinemia, hypertriglyceridemia, proteinuria, hepatomegaly, and positive antinuclear antibody. Bone marrow aspiration and trephine biopsy revealed hemophagocytosis and moderate myelofibrosis. The patient was diagnosed with SLE with concomitant autoimmune-associated hemophagocytic syndrome and autoimmune myelofibrosis. Treatment with high-dose corticosteroids led to dramatic clinical improvement with normalization of laboratory data and complete resolution of bone marrow hemophagocytosis and myelofibrosis. Hemophagocytosis and myelofibrosis, although uncommon, are possible initial manifestations of SLE and should be included in the differential diagnosis of cytopenias in SLE. Thorough clinical assessment and microscopic bone marrow examination and timely initiation of corticosteroid therapy are essential in the diagnosis and management of these potentially life-threatening conditions. This case emphasizes that the bone marrow is an important site of target organ damage in SLE, and evaluation of cytopenias in SLE should take this into consideration.

Bone marrow as a target organ of systemic lupus erythematosus: analysis of cases with myelofibrosis

AIM

Cytopenia in the course of systemic lupus erythematosus (SLE) may be due to multiple factors. In this study, we aimed primarily to evaluate the detailed results of bone marrow (BM) biopsies of SLE patients, secondly to determine the myelofibrosis (MF) frequency and thirdly to compare BM morphologic findings as well as the clinical and laboratory parameters between groups (with MF and without MF) in cytopenic SLE patients.

METHODS

We retrospectively analyzed 224 SLE patients' files. Patients were divided into two groups according to whether they had MF or not. Concurrent SLE organ involvements, medical therapy and detailed BM findings were recorded.

RESULTS

Forty-five (20%) of 224 SLE patients were found to have undergone BM biopsy due to cytopenia. Four patients were excluded (two drug-induced cytopenia, one lymphoma, one insufficient BM biopsy samples). While MF was detected in 29 (70.7%) of the 41 patients, 12 patients did not have MF. Between the two groups, no differences were identified in terms Systemic Lupus Erythematosus Disease Activity Index, BM cellularity, or BM dysplastic changes (P = 0.788, P = 0.672 and P = 0.494, respectively). In the SLE-associated MF group, 27 patients responded to immunosuppressive therapy and corticosteroids, but two patients were unresponsive. The response time was longer for the SLE-associated MF group compared to the without MF group (3.3 ± 3.1 months vs. 1.7 ± 1.2 months, P = 0.091). Correlation analysis revealed that increased degree of BM fibrosis delayed the response time (r = 0.471, P = 0.002).

CONCLUSIONS

MF is common in SLE patients. SLE-associated MF as an additional factor for cytopenia in SLE patients may lead to delayed response to appropriate therapy, which may be dependent on the increased grade of BM fibrosis.

The Critical Role of Inflammation in the Pathogenesis and Progression of Myeloid Malignancies

Hematopoietic stem cells (HSCs) maintain an organism's immune system for a lifetime, and derangements in HSC proliferation and differentiation result in hematologic malignancies. Chronic inflammation plays a contributory if not causal role in HSC dysfunction. Inflammation induces HSC exhaustion, which promotes the emergence of mutant clones that may be resistant to an inflammatory microenvironment; this likely promotes the onset of a myeloid hematologic malignancy. Inflammatory cytokines are characteristically high in patients with myeloid malignancies and are linked to disease initiation, symptom burden, disease progression, and worsened prognostic survival. This review will cover our current understanding of the role of inflammation in the initiation, progression, and complications of myeloid hematologic malignancies, drawing from clinical studies as well as murine models. We will also highlight inflammation as a therapeutic target in hematologic malignancies.

The role of extracellular matrix stiffness in megakaryocyte and platelet development and function

The extracellular matrix (ECM) is a key acellular structure in constant remodeling to provide tissue cohesion and rigidity. Deregulation of the balance between matrix deposition, degradation, and crosslinking results in fibrosis. Bone marrow fibrosis (BMF) is associated with several malignant and nonmalignant pathologies severely affecting blood cell production. BMF results from abnormal deposition of collagen fibers and enhanced lysyl oxidase-mediated ECM crosslinking within the marrow, thereby increasing marrow stiffness. Bone marrow stiffness has been recently recognized as an important regulator of blood cell development, notably by modifying the fate and differentiation process of hematopoietic or mesenchymal stem cells. This review surveys the different components of the ECM and their influence on stem cell development, with a focus on the impact of the ECM composition and stiffness on the megakaryocytic lineage in health and disease. Megakaryocyte maturation and the biogenesis of their progeny, the platelets, are thought to respond to environmental mechanical forces through a number of mechanosensors, including integrins and mechanosensitive ion channels, reviewed here.

Autoimmune Myelofibrosis: Clinical Features, Course, and Outcome

BACKGROUND

Autoimmune myelofibrosis (AIMF) is an underrecognized cause of nonmalignant bone marrow fibrosis which occurs in the presence or absence of a defined systemic autoimmune disease. Patients with AIMF present with cytopenias and autoantibodies, and have a distinctive nonclonal myelofibrosis on bone marrow examination. AIMF is distinguished from primary myelofibrosis by the absence of splenomegaly, eosinophilia, or basophilia, and the absence of abnormal myeloid, erythroid, or megakaryocytic morphology.

OBJECTIVES

The objective of the study was to describe the clinical presentation and outcomes of patients with AIMF.

METHODS

We conducted a single-institution, retrospective chart review of patients diagnosed with AIMF to investigate clinical presentations, therapies, and outcomes.

RESULTS

Twelve patients with AIMF were identified with a mean follow-up of 5.8 years. All patients had detectable autoantibodies and the majority had concomitant autoimmune disorders. Four patients experienced a complete response of cytopenias and 3 patients experienced a partial response (PR) of cytopenias with immunosuppressive therapy. One patient achieved a PR following splenectomy. No patients were diagnosed with myeloproliferative neoplasms during the follow-up period.

CONCLUSIONS

AIMF contributes to cytopenias in the subset of patients with various autoimmune disorders. The majority of patients with AIMF experience an improvement in cytopenias with immunosuppressive therapy.

Steroid-resistant autoimmune myelofibrosis in a patient with autoimmune hepatitis and Evans syndrome complicated with increased expression of TGF-β in the bone marrow: a case report

We here report a 47-year-old female with autoimmune myelofibrosis (AIMF) associated with liver damage caused by autoimmune hepatitis and Evans syndrome. Bone marrow biopsy revealed hypocellular marrow with grade 2 reticulin fibrosis and increased levels of B lymphocytes (CD20⁺), T lymphocytes (CD3⁺, CD8⁺), and plasma cells (CD138⁺). Immunohistochemical analysis revealed increased expression of transforming growth factor-β (TGF-β) in infiltrating lymphocytes and macrophages in the bone marrow. She was initially treated with oral prednisolone (PSL) for 2 months, which had a limited effect. However, after treatment with rituximab, the patient's pancytopenia showed improvement, allowing us to rapidly reduce the PSL dosage. The present case suggests the possibility that increased expression of TGF-β in infiltrating lymphocytes and macrophages of bone marrow may contribute to the pathogenesis of AIMF. Prednisolone combined with rituximab may thus be an effective option for steroid-refractory cases.

Histologic and cytologic bone marrow findings in dogs with suspected precursor-targeted immune-mediated anemia and associated phagocytosis of erythroid precursors

BACKGROUND

Precursor-targeted immune-mediated anemia (PIMA) has been suspected in dogs with nonregenerative anemia and bone marrow findings varying from erythroid hyperplasia to pure red cell aplasia. Phagocytosis of erythroid precursors/rubriphagocytosis (RP) reported in some affected dogs suggests a destructive component to the pathogenesis of PIMA.

OBJECTIVES

The purpose of the study was to characterize laboratory and clinical findings in dogs with suspected PIMA and RP, with emphasis on cytologic and histologic bone marrow findings.

METHODS

Dogs with PIMA and RP were identified by review of paired bone marrow aspirate and core biopsy slides collected over a 4-year period. Samples were systematically assessed and characterized along with other pertinent laboratory data and clinical findings.

RESULTS

Twenty-five dogs met criteria for PIMA and had RP that was relatively stage-selective. Erythropoiesis was expanded to the stage of erythroid precursors undergoing most prominent phagocytosis, yielding patterns characterized by a hypo-, normo-, or hypercellular erythroid lineage. A 4^th pattern involved severe collagen myelofibrosis, and there was a spectrum of mild to severe collagen myelofibrosis overall. Evidence of immune-mediated hemolysis was rare. Immunosuppressive therapy was associated with remission in 77% of dogs treated for at least the median response time of 2 months.

CONCLUSIONS

Bone marrow patterns in dogs fulfilling criteria for PIMA were aligned with stage-selective phagocytosis of erythroid precursors and the development of collagen myelofibrosis, common in dogs with PIMA. Recognition of these patterns and detection of RP facilitates diagnosis of PIMA, and slow response to immunosuppressive therapy warrants further investigation into its pathogenesis.

A rare cause of cytopenia in a patient with systemic lupus erythematosus: Autoimmune myelofibrosis

Hematological abnormalities are very common in the course of systemic lupus erythematosus (SLE). Myelofibrosis is a bone marrow disorder in which there is excessive fibrous tissue formation in the bone marrow. Various benign and malignant disorders can cause or be associated with a diffuse increase in the bone marrow reticular tissue. Some diseases such as infections, neoplasms, and autoimmune diseases may also induce bone marrow fibrosis (secondary myelofibrosis). Cytopenia from autoimmune myelofibrosis (AIMF) in SLE is a rare condition. Here we present a case of AIMF associated with SLE and aim to emphasize on the other cause of cytopenia in SLE.

The myeloproliferative neoplasms, unclassifiable: clinical and pathological considerations

In this study, we investigate in detail the morphological, clinical and molecular features of 71 consecutive patients with a diagnosis of myeloproliferative neoplasms, unclassifiable. We performed a meticulous morphological analysis and found that most of the cases displayed a hypercellular bone marrow (70%) with normal erythropoiesis without left-shifting (59%), increased granulopoiesis with left-shifting (73%) and increased megakaryocytes with loose clustering (96%). Megakaryocytes displayed frequent giant forms with hyperlobulated or bulbous nuclei and/or other maturation defects. Interestingly, more than half of the cases displayed severe bone marrow fibrosis (59%). Median values of hemoglobin level and white blood cells count were all within the normal range; in contrast, median platelets count and lactate dehydrogenase were increased. Little less than half of the patients (44%) showed splenomegaly. JAK2V617F mutation was detected in 72% of all patients. Among the JAK2-negative cases, MPLW515L mutation was found in 17% and CALR mutations in 67% of the investigated cases, respectively. Finally, by multiple correspondence analysis of the morphological profiles, we found that all but four of the cases could be grouped in three morphological clusters with some features similar to those of the classic BCR-ABL1-negative myeloproliferative neoplasms. Analysis of the clinical parameters in these three clusters revealed discrepancies with the morphological profile in about 55% of the patients. In conclusion, we found that the category of myeloproliferative neoplasm, unclassifiable is heterogeneous but identification of different subgroups is possible and should be recommended for a better management of these patients.

A 2-Year, Longitudinal, Prospective Study of the Effects of Eltrombopag on Bone Marrow in Patients with Chronic Immune Thrombocytopenia

BACKGROUND

The long-term effects of eltrombopag on bone marrow (BM) reticulin and/or collagen deposition in previously treated adults with chronic immune thrombocytopenia (ITP) were assessed.

METHODS

Three BM biopsies were collected at baseline and after 1 and 2 years of eltrombopag treatment. Specimens were centrally processed, stained for reticulin and collagen, independently reviewed by 2 hematopathologists, and rated according to the European Consensus 0-3 scale of marrow fibrosis (MF).

RESULTS

Of 162 patients enrolled, 93 completed all 3 protocol-specified BM biopsies. All patients with a baseline assessment were negative for collagen. Of 159 patients assessed at baseline, 150 (94%) had normal reticulin (MF-0) and 9 (6%) had minimally increased reticulin (MF-1). After 2 years, 83/93 patients (89%) with BM biopsies had MF-0, 10 (11%) had MF-1, and none had MF-2 or MF-3. Five out of 127 patients (4%) at 1 year and 1 out of 93 (1%) at 2 years had collagen deposition. None of the patients had clinical symptoms typical of BM dysfunction or abnormalities of clinical concern based on white blood cell count or peripheral blood smear.

CONCLUSION

For most patients with chronic ITP, eltrombopag is not associated with clinically relevant increases in BM reticulin or collagen formation.

Primary autoimmune myelofibrosis with severe thrombocytopenia mimicking immune thrombocytopenia: A case report

Patients presenting with bone marrow fibrosis not accompanied by well-established autoimmune diseases, such as systemic lupus erythematosus, or malignant diseases, are considered to have primary autoimmune myelofibrosis (AIMF). Primary AIMF has been reported to follow a benign course and responds well to treatment with immunosuppressive agents. Immune thrombocytopenia (ITP) is also an autoimmune disorder characterized by antiplatelet-antibody-mediated thrombocytopenia in the absence of other causes of thrombocytopenia. We herein present a rare case of a female patient who was diagnosed with primary AIMF. The patient presented with severe thrombocytopenia, which was initially misdiagnosed as ITP. The symptoms of the disease resolved completely following steroid treatment. After withdrawal of the treatment at 1 year from the diagnosis, the bone marrow examination showed no evidence of bone marrow fibrosis or other abnormalities. To date, the patient has been followed up for 2 years without evidence of disease.

Idiopathic Acquired Osteosclerosis in a Middle-Aged Woman With Systemic Lupus Erythematosus

Widely distributed osteosclerosis is an unusual radiographic finding with multiple causes. A 42-year-old premenopausal Spanish woman gradually acquired dense bone diffusely affecting her axial skeleton and focally affecting her proximal long bones. Systemic lupus erythematosus (SLE) diagnosed in adolescence had been well controlled. She had not fractured or received antiresorptive therapy, and she was hepatitis C virus antibody negative. Family members had low bone mass. Lumbar spine bone mineral density (BMD) measured by dual-photon absorptiometry (DPA) at age 17 years, while receiving glucocorticoids, was 79% the average value of age-matched controls. From ages 30 to 37 years, dual-energy X-ray absorptiometry (DXA) BMD Z-scores steadily increased in her lumbar spine from +3.8 to +7.9, and in her femoral neck from -1.4 to -0.7. Serum calcium and phosphorus levels were consistently normal, 25-hydroxyvitamin D (25OHD) <20 ng/mL, and parathyroid hormone (PTH) sometimes slightly increased. Her reduced estimated glomerular filtration rate (eGFR) was 38 to 55 mL/min. Hypocalciuria likely reflected positive mineral balance. During increasing BMD, turnover markers (serum bone-specific alkaline phosphatase [ALP], procollagen type 1 N propeptide [P1NP], osteocalcin [OCN], and carboxy-terminal cross-linking telopeptide of type 1 collagen [CTx], and urinary amino-terminal cross-linking telopeptide of type 1 collagen [NTx and CTx]) were 1.6- to 2.8-fold above the reference limits. Those of bone formation seemed increased more than those of resorption. FGF-23 was slightly elevated, perhaps from kidney disease. Serum osteoprotegerin (OPG) and TGFβ1 levels were normal, but sclerostin (SOST) and receptor activator of nuclear factor kappa-B ligand (RANKL) were elevated. Serum multiplex biomarker profiling confirmed a high level of SOST and RANKL, whereas Dickkopf-1 (DKK-1) seemed low. Matrix metalloproteinases-3 (MMP-3) and -7 (MMP-7) were elevated. Iliac crest biopsy revealed tetracycline labels, no distinction between thick trabeculae and cortical bone, absence of peritrabecular fibrosis, few osteoclasts, and no mastocytosis. Then, for the past 3 years, BMD Z-scores steadily decreased. Skeletal fluorosis, mastocytosis, myelofibrosis, hepatitis C-associated osteosclerosis, multiple myeloma, and aberrant phosphate homeostasis did not explain her osteosclerosis. Mutation analysis of the LRP5, LRP4, SOST, and osteopetrosis genes was negative. Microarray showed no notable copy number variation. Perhaps her osteosclerosis reflected an interval of autoimmune-mediated resistance to SOST and/or RANKL. © 2016 American Society for Bone and Mineral Research.