Pathology of autoimmune myelofibrosis. A report of three cases and a review of the literature

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.

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.

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.

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.

Bone marrow involvement in systemic lupus erythematosus

BACKGROUND

Besides peripheral cytopenias, bone marrow abnormalities, such as fibrosis, pure red cell aplasia and aplastic anemia have been reported in patients with systemic lupus erythematosus (SLE), suggesting that bone marrow may be a 25 target organ in SLE.

AIM

Our objective was to describe this bone marrow involvement.

METHODS

This registry is a nationwide retrospective study. Centers provided data concerning medical history, SLE manifestations, type of hematologic disorder, treatments and outcome. Bone marrow aspirations and/or biopsies were transferred for centralized review.

RESULTS

Thirty patients from 19 centers were included. Central hematologic manifestations comprised bone marrow fibrosis (n = 17; 57%), pure red cell aplasia (n = 8; 27%), myelodysplastic syndrome (n = 3; 10%), aplastic anemia and agranulocytosis (n = 1; 3% each). Bone marrow involvement was diagnosed concomitantly with SLE in 12 patients. Bone marrow biopsies showed fibrosis in 19 cases, including one case of pure red cell aplasia and one case of agranulocytosis and variable global marrow cellularity. Treatments included corticosteroids (90%), hydroxychloroquine (87%), rituximab (33%), intravenous immunoglobulins (30%), mycophenolate mofetil (20%) and ciclosporine (20%). After a median follow-up of 27 months (range: 1-142), 24 patients manifested complete improvement. No patient died.

CONCLUSIONS

This registry comprises the largest series of SLE patients with bone marrow involvement. It demonstrates the strong link between SLE and bone marrow fibrosis. Patients with atypical or refractory cytopenia associated with SLE should undergo bone marrow examination to enable appropriate, and often effective, treatment. Long-term prognosis is good.

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.

Primary myelofibrosis: current therapeutic options

Primary myelofibrosis is a Philadelphia-negative myeloproliferative neoplasm characterized by clonal myeloid expansion, followed by progressive fibrous connective tissue deposition in the bone marrow, resulting in bone marrow failure. Clonal evolution can also occur, with an increased risk of transformation to acute myeloid leukemia. In addition, disabling constitutional symptoms secondary to the high circulating levels of proinflammatory cytokines and hepatosplenomegaly frequently impair quality of life. Herein the main current treatment options for primary myelofibrosis patients are discussed, contemplating disease-modifying therapeutics in addition to palliative measures, in an individualized patient-based approach.

Fibrogenesis in Primary Myelofibrosis: Diagnostic, Clinical, and Therapeutic Implications

Primary myelofibrosis is a stem cell-derived clonal malignancy characterized by unchecked proliferation of myeloid cells, resulting in bone marrow fibrosis, osteosclerosis, and pathologic angiogenesis. Bone marrow fibrosis (BMF) plays a central role in the pathophysiology of the disease. This review describes current issues regarding BMF in primary myelofibrosis, including the pathophysiology and impact of abnormal deposition of excess collagen and reticulin fibers in bone marrow spaces, the modified Bauermeister and the European Consensus grading systems of BMF, and the prognostic impact of BMF on the overall outcome of patients with primary myelofibrosis. The impact of novel therapeutic strategies, including JAK-STAT inhibitors and allogeneic stem cell transplant, on BMF is discussed.

Association of long-term tacrolimus (FK506) therapy with abnormal megakaryocytosis, bone marrow fibrosis, and dyserythropoiesis

Haematopoietic abnormalities associated with tacrolimus are relatively rare with reversible pure red cell aplasia being the most common. We report for the first time, to our best knowledge, tacrolimus therapy associated with bone marrow fibrosis, abnormal megakaryocytosis, and dyserythopoiesis in a 17-year-old male treated with tacrolimus for nephrotic syndrome.

Autoimmune myelofibrosis and systemic lupus erythematosus in a middle-aged male presenting only with severe anemia: a case report

Autoimmune myelofibrosis is a distinct clinicopathologic entity that occasionally occurs with autoimmune disorders such as systemic lupus erythematosus (SLE) and rheumatoid arthritis. Most cases of autoimmune myelofibrosis have been reported in female patients with a known history of SLE. We report a case of a middle-aged male patient with an unusual presentation of SLE and autoimmune myelofibrosis who presented only with severe anemia initially and was later diagnosed with SLE and autoimmune myelofibrosis. The patient's condition improved dramatically after treatment with corticosteroids.SLE and autoimmune myelofibrosis is a rare but potentially devastating condition. Anemia maybe the only presenting symptom in addition to bone marrow fibrosis and careful clinical and laboratory assessment is imperative. Corticosteroids maybe useful and spare patients from bone marrow transplantation.

Autoimmune Myelofibrosis in Systemic Lupus Erythematosus Report of Two Cases and Review of the Literature

Autoimmune myelofibrosis (AIMF) is a rare entity of steroid-responsive bone marrow fibrosis that accompanies a variety of autoimmune diseases, particularly systemic lupus erythematosus (SLE). Rarely it may occur in patients with autoimmune markers but no definable autoimmune disease (Primary-AIMF). We report the cases of two young women with SLE-associated AIMF (SLE-AIMF). The first patient was a young woman who had pancytopenia, massive splenomegaly and reticulin fibrosis in the marrow biopsy. The pancytopenia and splenomegaly resolved completely within weeks of treatment with corticosteroids. Repeat marrow biopsy showed marked regression of marrow fibrosis. The second patient was a young woman with fever, anasarca, bicytopenia and reticulin fibrosis in the marrow biopsy. Steroid therapy resulted in rapid clinical improvement and resolution of pancytopenia. A review of the literature revealed a total of 30 patients with SLE-AIMF reported to-date. Patients with SLE-AIMF are young women with SLE and blood cytopenia who are found to have increased bone marrow reticulin on marrow biopsy. Steroid therapy results in rapid hematological recovery and regression of marrow fibrosis. Whether AIMF is one of several hematological complications of SLE, or represents a unique and distinct subset of patients with SLE in not clear. Prospective studies with longer follow-up are needed to better define the prevalence and clinical spectrum of SLE-AIMF.

Aplastic anemia as a feature of systemic lupus erythematosus: a case report and literature review

Peripheral cytopenias are common in systemic lupus erythematosus, but bone marrow involvement is rarely reported. Aplastic anemia is the result of immune-mediated destruction of hematopoietic stem cells causing pancytopenia and characterized by an empty bone marrow. This rare but serious disease has been described as an unusual manifestation of systemic lupus erythematosus. We reviewed the 25 cases published in the English language literature and discuss the clinical presentation, outcome, treatment, and pathophysiology of aplastic anemia as a complication of systemic lupus erythematosus. We report here the first case of aplastic anemia associated with systemic lupus erythematosus treated with an allogeneic hematopoietic stem cell transplant. Over one half of patients received concomitantly the diagnoses of systemic lupus erythematosus and aplastic anemia. No clinical or histological features can distinguish primary aplastic anemia from aplastic anemia occurring in systemic lupus erythematosus patients. The overall mortality is about 15% and corticosteroid-based therapy alone or in combination with other immunomodulatory drugs can restore bone marrow function. Systemic lupus erythematosus may be complicated by bone marrow involvement. The diagnosis of peripheral cytopenias should be confirmed by bone marrow aspiration. All these patients should receive cortisone as a first treatment. Plasma exchanges seem to have some efficacy. Other different immunomodulatory therapies were used with variable results.

Bone marrow fibrosis as a feature of systemic lupus erythematosus: a case report and literature review

Introduction

Peripheral cytopenias are common in systemic lupus erythematosus (SLE), but bone marrow involvement is rarely reported. Myelofibrosis is a rare disorder characterized by reticulin fibrosis of the bone marrow, which usually occurs in response to clonal proliferation of hematopoietic stem cells in myeloproliferative disorders. However, bone marrow fibrosis has also been described in association with auto-immune diseases, especially SLE.

Method

We will report here a new case of bone marrow fibrosis associated with SLE. We also reviewed the 27 cases published in the English language literature, and will discuss the clinical presentation, outcome, treatment, and pathophysiology of bone marrow fibrosis occurring in association with SLE.

Results

Over one half of patients were diagnosed concomitantly with bone marrow fibrosis and SLE. Epidemiological, clinical and biological features of lupus were unremarkable. Except for the presence of reticulin fibrosis, the findings from the bone marrow biopsies proved highly variable. Overall mortality was about 14% but corticosteroid-based therapy lead to clinical improvement and reverted bone marrow fibrosis in most cases. Data on the usefulness of other immunomodulatory therapies are inconclusive.

Conclusions

SLE may be complicated by bone marrow involvement, of a likely autoimmune origin. Bone marrow fibrosis occurring with SLE is probably similar to “primary autoimmune myelofibrosis” and may respond to steroid and immunomodulatory therapies. Further studies with standardised proofreading of bone marrow aspirations and biopsies are needed to delineate the clinical and biological features of this rare complication of SLE.

Myelofibrosis-related arthritis successfully treated with hydroxyurea

A 62-year-old woman suffering from one-year lasting, nonerosive peripheral arthritides with general health impairment and high acute-phase reactant levels was admitted to rheumatology department. The patient had suffered from chronic polyarthralgia and a thrombocytosis had been discovered 9 years before, with a recent increase in platelet count. All immunological blood tests were negative. Corticosteroid and methotrexate treatments improved pain, swollen joint count, and systemic inflammation. However, joints remained stiff and painful with two swollen wrists and persistent thrombocytosis. An iliac bone marrow biopsy was performed, showing primary myelofibrosis. Hydroxyurea treatment (500 mg per day) allowed to achieve complete and prolonged clinical and biological remission. After 6 months, a new disease flare occurred. The patient reached remission again after hydroxyurea dose increased to 1500 mg per day. This supports the hypothesis of idiopathic myelofibrosis-associated seronegative polyarthritis. This is the first reported case in which haemopathy-targeted treatment using hydroxyurea induced arthritis remission.

Autoimmune myelofibrosis accompanied by Sjögren's syndrome in a 47, XXX/46, XX mosaic woman

This report describes a patient with autoimmune myelofibrosis accompanied by Sjögren's syndrome (SS). A 36-year-old woman was admitted due to petechiae, purpura, gingival bleeding, dyspnea on exertion, and a lack of concentration. She had pancytopenia and was diagnosed with SS. A bone marrow study showed hypercellular marrow with reticulin fibrosis. Lymphocytic infiltrates and aggregates composed of a mixture of T and B cells in the marrow were also observed. A chromosomal analysis of the marrow cells showed 47, XXX and an analysis of peripheral lymphocytes revealed 47, XXX/46, XX mosaic results. The patient's cytopenia resolved following treatment with oral prednisolone.

Bone Marrow Examination for Unexplained Cytopenias Reveals Nonspecific Findings in Patients With Collagen Vascular Disease

Context.—Collagen vascular diseases are frequently included in the differential diagnosis for unexplained cytopenias and often prompt a bone marrow biopsy in this patient population to exclude malignancy. Few large-scale studies have characterized the bone marrow morphology in patients with collagen vascular disease, and most are limited to systemic lupus erythematosus or rheumatoid arthritis.

Objective.—To identify morphologic and immunohistochemical abnormalities specific to each of a wide range of collagen vascular disease cases.

Design.—We examined 102 cases of collagen vascular disease and 38 controls and evaluated the complete blood count, peripheral blood morphology, bone marrow morphology, as well as immunohistochemical staining, for numerous cell lineages.

Results.—Bone marrow findings, including abnormalities such as lymphoid aggregates, lipogranulomas, or abnormal localization of immature precursors, were not significantly different as compared to the control group.

Conclusions.—Bone marrow examination in patients with collagen vascular disease with cytopenias seldom provides new information. Caution should be exercised in interpreting morphologic findings suggestive of myelodysplasia since these are of a reactive nature in up to 27% of patients with collagen vascular disease. In a cost-effective diagnostic strategy, successful utilization may favor postponing a bone marrow biopsy while a more standardized autoimmune diagnostic panel is being performed.

The differential diagnosis and bone marrow evaluation of new-onset pancytopenia

New-onset pancytopenia can be caused by a wide variety of etiologies, leading to a diagnostic dilemma. These etiologies range from congenital bone marrow failure to marrow space-occupying lesions, infection, and peripheral destruction, to name a few. Bone marrow examination, in addition to a detailed clinical history, is often required for an accurate diagnosis. The purpose of this review is to provide a brief overview of many of the causes of new-onset pancytopenia in adults and children, with emphasis on bone marrow findings and recommendations of additional testing and clinical evaluation when needed, with the overall aim of aiding the pathologist's role as a consultant to the patient's treating physician.

Bone marrow fibrosis: pathophysiology and clinical significance of increased bone marrow stromal fibres

In bone marrow biopsies, stromal structural fibres are detected by reticulin and trichrome stains, routine stains performed on bone marrow biopsy specimens in diagnostic laboratories. Increased reticulin staining (reticulin fibrosis) is associated with many benign and malignant conditions while increased trichrome staining (collagen fibrosis) is particularly prominent in late stages of severe myeloproliferative diseases or following tumour metastasis to the bone marrow. Recent evidence has shown that the amount of bone marrow reticulin staining often exhibits no correlation to disease severity, while the presence of type 1 collagen, as detected by trichrome staining, is often associated with more severe disease and a poorer prognosis. It was originally thought that increases in bone marrow stromal fibres themselves contributed to the haematopoietic abnormalities seen in certain diseases, but recent studies suggest that these increases are a result of underlying cellular abnormalities rather than a cause. A growing body of evidence suggests that increased deposition of bone marrow stromal fibres is mediated by transforming growth factor-beta and other factors elaborated by megakaryocytes, but it is likely that other cells, cytokines and growth factors are also involved. This suggests new avenues for investigation into the pathogenesis of various disorders associated with increased bone marrow stromal fibres.

Peripheral monocytes and CD4+ cells are potential sources for increased circulating levels of TGF-beta and substance P in autoimmune myelofibrosis

Myelofibrosis is an uncommon phenomenon associated with a variety of neoplastic and inflammatory processes. Although there is evidence that cytokines elaborated by clonal malignant hematopoietic cells are implicated in myelofibrosis in primary hematologic disorders, there has been little data to date on the pathophysiology of myelofibrosis in autoimmune disorders. Here we report a case of autoimmune myelofibrosis with pancytopenia. Peripheral blood monocytes and CD4-positive lymphocytes produced significantly elevated levels of transforming growth factor beta (TGF-beta) compared to similar cells from healthy volunteer controls. TGF-beta has been implicated in the pathogenesis of myelofibrosis associated with primary hematological malignancies. Furthermore, substance P, previously linked to myelofibrosis, was also detected in elevated levels in the patient's serum and correlated negatively with the levels of the patient's blood counts. These findings suggest a role for both TGF-beta and substance P in the pathophysiology of autoimmune myelofibrosis. This is the first report of deregulated production of TGF-beta by monocytes in the pathobiology of autoimmune myelofibrosis.

Paroxysmal cold haemoglobinuria as a tardive complication of idiopathic myelofibrosis

Paroxysmal cold haemoglobinuria (PCH) is an autoimmune haemolytic anaemia caused by the Donath-Landsteiner antibody. It is classically described in association with chronic syphilis or after acute viral infections. We describe the first case of PCH presented as a late manifestation of advanced myelofibrosis associated with antiphospholipid syndrome, that promptly responded to high dosage of prednisone.

Dermatomyositis and myelodysplastic syndrome with myelofibrosis responding to methotrexate therapy

Dermatomyositis (DM) has not yet been reported as a complication of myelodysplastic syndrome (MDS). A 50-year-old man was diagnosed as having MDS because of the presence of anemia, the appearance of immature cells in peripheral blood, and the abnormal cellular morphology. A few months later, high fever, myalgia and erythema developed. Although DM symptoms were resistant to high-dose corticosteroid administration, methotrexate (MTX) therapy improved not only the symptoms of DM but also hematologic findings related to MDS. This indicates that immunosuppressive therapy including MTX administration can be useful for patients with MDS with autoimmune symptoms.

Primary autoimmune myelofibrosis: definition of a distinct clinicopathologic syndrome

Myelofibrosis is characterized by reticulin fibrosis of the bone marrow with resulting features of myelophthisis. Besides hematopoietic malignancies and other neoplasms involving the bone marrow, myelofibrosis has been described in association with autoimmune disorders, especially systemic lupus erythematosus. We describe the clinicopathologic features of a primary form of autoimmune myelofibrosis (AIMF) in patients who do not have systemic lupus erythematosus or another well-defined autoimmune syndrome. Absence of marked splenomegaly, peripheral blood cytopenias with mild teardrop poikilocytosis and leukoerythroblastosis, bone marrow lymphoid aggregates, and presence of autoantibodies are some of the salient features of primary AIMF. AIMF should especially be differentiated from chronic idiopathic myelofibrosis, a neoplastic myeloproliferative disease. Primary AIMF appears to have an excellent prognosis, with all patients reported in this series responding to a short course of corticosteroid therapy.

Idiopathic myelofibrosis associated with ulcerative colitis

A patient with ulcerative colitis (UC) who developed idiopathic myelofibrosis (IM) is reported. The initial diagnosis of UC was established by colonoscopy and large bowel biopsy, performed after a one-month history of abdominal pain and bloody diarrhea. The patient showed a favorable response to prednisone and mesalamine treatment and six months later he developed a new episode of UC, which was successfully controlled with treatment. However, two years later splenomegaly and anemia were observed, with aniso-poikilocytosis, tear-drop cells, immature myeloid precursors in the peripheral blood, and increased serum LDH, arising the suspicion of IM, a diagnosis that was confirmed by bone marrow biopsy. The present case represents a new association of IM with an autoimmune disease and gives support to the hypothesis of a possible immune basis of some IM cases.