Anaemia of the elderly (AOE): does it exist and does it matter in clinical practice?

Normal and pathological erythropoiesis in adults: from gene regulation to targeted treatment concepts

Pathological erythropoiesis with consequent anemia is a leading cause of symptomatic morbidity in internal medicine. The etiologies of anemia are complex and include reactive as well as neoplastic conditions. Clonal expansion of erythroid cells in the bone marrow may result in peripheral erythrocytosis and polycythemia but can also result in anemia when clonal cells are dysplastic and have a maturation arrest that leads to apoptosis and hinders migration, a constellation typically seen in the myelodysplastic syndromes. Rarely, clonal expansion of immature erythroid blasts results in a clinical picture resembling erythroid leukemia. Although several mechanisms underlying normal and abnormal erythropoiesis and the pathogenesis of related disorders have been deciphered in recent years, little is known about specific markers and targets through which prognosis and therapy could be improved in anemic or polycythemic patients. In order to discuss new markers, targets and novel therapeutic approaches in erythroid disorders and the related pathologies, a workshop was organized in Vienna in April 2017. The outcomes of this workshop are summarized in this review, which includes a discussion of new diagnostic and prognostic markers, the updated WHO classification, and an overview of new drugs used to stimulate or to interfere with erythropoiesis in various neoplastic and reactive conditions. The use and usefulness of established and novel erythropoiesis-stimulating agents for various indications, including myelodysplastic syndromes and other neoplasms, are also discussed.

Anemia at older age: etiologies, clinical implications, and management

Anemia is quite frequently diagnosed in older individuals and is a key indicator of various reactive and clonal conditions. Many underlying diseases, like myelodysplastic syndrome (MDS), develop preferentially in elderly individuals. The prevalence of anemia at older age is increasing, and this is mainly attributable to more frequently applied diagnostics and demographic changes in our societies. The etiology of anemia at older age is complex and ranges from bone marrow failure syndromes to chronic kidney disease, and from nutritional deficiencies to inflammatory processes including inflammaging in immunosenescence. In a smaller number of cases, no clear-cut etiology is identified. These patients are referred to as unexplained anemia or idiopathic cytopenia of unknown significance. In others, somatic mutations in leukocytes are found, but diagnostic criteria for MDS or other hematologic diseases are not fulfilled, a condition termed clonal cytopenia of undetermined significance. Management of anemias at older age depends on (1) the severity of the anemia, (2) underlying condition(s), and (3) patient-related factors, including comorbidities. Even a mild anemia may substantially affect physical and cognitive capacities and quality of life. An underestimated aspect is that because of age-related changes, organ function such as erythropoietin production in the kidney may become suboptimal. Management and treatment of anemia in older patients often require a multidisciplinary approach and detailed investigations of organ function. In this article, we review current concepts around anemias at older age, with special emphasis on etiologies, clinical implications, and innovative concepts in the management of these patients.

Low blood counts: immune mediated, idiopathic, or myelodysplasia

Traditionally, cytopenias are classified as deficiency mediated, immune mediated, BM failure induced, renal, or idiopathic, with the latter including the so-called idiopathic cytopenias of undetermined significance (ICUS). Clinical findings, symptoms, blood counts, BM findings, and other laboratory parameters are usually sufficient to reveal the type and cause of a marked cytopenia. However, in patients with chronic mild cytopenia, it may be a challenge for the physician to establish a correct diagnosis. In such patients, laboratory features and findings often reflect a diagnostic interface, so that criteria that are otherwise robust may hardly be applicable or are not helpful. Even if the BM is examined, the diagnosis often remains uncertain in these patients. In addition, more than one potential cause of cytopenia may be present, especially in the elderly. A myelodysplastic syndrome (MDS) or another BM disorder, but also an overt autoimmune or other inflammatory disease, may develop during follow-up in these patients. A key problem is that in an early phase of MDS, most laboratory and clinical signs are “nonspecific.” One of the very few reliable peripheral blood parameters distinguishing between an early or “pre-phase” of MDS and most other causes of a mild cytopenia are the numbers of circulating colony-forming progenitor cells. In addition, flow cytometric and molecular investigations may sometimes assist in the delineation between clonal and reactive conditions underlying mild cytopenias. This review provides an overview of diagnostic approaches and algorithms for patients with mild unexplained cytopenia(s).

Idiopathic cytopenia of undetermined significance (ICUS) and idiopathic dysplasia of uncertain significance (IDUS), and their distinction from low risk MDS

It is now generally appreciated that hematologic neoplasms can develop over many years if not decades, often being initially occult or showing minimal (subdiagnostic) abnormalities. However, whereas such early neoplastic conditions have been defined in some detail in lymphoproliferative neoplasms, little is known about minimal lesions preceding the manifestation of an overt myeloid neoplasm, about underlying mechanisms, the clinical course and outcome, and the prognostic significance of such conditions. Members of several groups have recently described two 'premalignant' myeloid conditions, namely idiopathic cytopenia of undetermined significance (ICUS) and idiopathic bone marrow dysplasia of uncertain significance (IDUS). At least in some patients these are neoplastic conditions. Both conditions may progress to an overt myelodysplastic syndrome (MDS), but may also progress to another myeloid neoplasm such as acute myeloid leukemia, a myeloproliferative neoplasm (MPN), or a mast cell disorder (mastocytosis). In ICUS the dysplasia is mild and does not fulfill the WHO criteria for MDS but cytopenias can be severe. In IDUS the dysplasia is prominent but cytopenias, if detectable, are mild. In both conditions it is possible that a neoplastic clone has already replaced most or all of normal bone marrow cells when ICUS or IDUS is detected, but evidence to support this possibility is not necessarily available. For both groups of patients we recommend a thorough hematologic follow up because of the potential of disease-manifestation and the unpredictable form and time of progression. In the present review, we discuss current concepts relating to ICUS and IDUS as well as diagnostic approaches and available criteria.