[Myelofibrosis: A review]. / Les myélofibroses.

Myelofibrosis is a BCR-ABL1-negative chronic myeloproliferative neoplasm that includes primary myelofibrosis, post-polycythemia vera myelofibrosis, and post-essential thrombocythemia myelofibrosis. It is characterized by stem cell-derived clonal proliferation that is often, but not always, accompanied by somatic mutations, which are classified into driver mutations (JAK2, CALR, or MPL), subclonal mutations and fibrosis on bone marrow biopsy. Myelofibrosis commonly demonstrates splenomegaly, constitutional symptoms, anemia, thrombocytosis, or thrombocytopenia. Patients may also be asymptomatic. Complications as thromboembolic or hemorrhagic events can reveal the disease. Primary myelofibrosis is the least common myeloproliferative neoplasm but is associated with poor survival and acute leukemic transformation. In contrast to the significant progress made in understanding the disease's pathogenesis, treatment for myelofibrosis remains largely palliative. The JAK2 inhibitor, ruxolitinib is not sufficient in eliminating the underlying myeloid progenitor clone, as disease inevitably returns with therapy discontinuation. Allogeneic hematopoietic stem cell transplantation is the only therapeutic option that offers potential cure. The development of novel treatment strategies aimed at slowing or even reversing disease progression, prolonging patient survival and preventing evolution to blast-phase are still lacking.

[Polyarteritis nodosa, an alternative diagnosis of giant cell arteritis in cases of temporal arteritis]. / La périartérite noueuse, un diagnostic alternatif à l'artérite gigantocellulaire devant une artérite temporale.

INTRODUCTION: Weight loss, myalgias, neurologic manifestations and arterial hypertension are common features of polyarteritis nodosa (PAN) at diagnosis. Temporal arteritis is a rarer manifestation of PAN, more suggestive of giant cell arteritis (GCA). CASE: We report the case of a 77-year-old woman who presented with fatigue, weight loss, fever, neck pain, jaw claudication and cough, diagnosed with giant cell arteritis. Diagnosis was reconsidered in favour of a medium and small-sized vessels necrotizing vasculitis corresponding to PAN because of steroid dependence, mononeuritis and suggestive histological features. CONCLUSION: Although temporal arteritis is suggestive of GCA, other causes of temporal arteritis can be identified with temporal artery biopsy.