Hoyer, James D.

Abstract Abstract 986 In 2011, we described the TEMPI syndrome in three patients, a rare condition characterized by the pentad of (1) Telangiectasias, (2) elevated Erythropoietin and resulting erythrocytosis, (3) Monoclonal gammopathy, (4) Perinephric fluid collections, and (5) Intrapulmonary shunting. Since this publication, two additional living patients have been identified. Of note, all patients carried a diagnosis of unexplained polycythemia for many years to decades prior to the realization that the erythrocytosis was only one part of a more complex syndrome. The underlying pathophysiology of the TEMPI syndrome is unknown. Given that the patients did not exhibit symptoms until their 3rd or 4th decade, we felt that the TEMPI syndrome was more likely to be acquired and less likely to be congenital. We hypothesized that the monoclonal paraprotein may play a role in triggering this very unusual pattern of symptoms. Based on this hypothesis, the patients began empiric treatment with the proteasome inhibitor bortezomib, either alone, or as part of an induction regimen prior to autologous stem cell transplantation. The first patient to receive bortezomib, a 48 year old woman, received 8 cycles of intravenous bortezomib, given in standard fashion. Her telangiectasias, which were concentrated over her lips and torso, disappeared rapidly. Her bilateral perinephric fluid collections disappeared and her serum erythropoietin normalized from a peak of >5000 mIU/ml. By the end of the 8 cycles, her IgG kappa paraprotein became undetectable. Before treatment, she was hypoxic to such a degree that she required a wheelchair and continuous supplemental oxygen. Following treatment, her intrapulmonary shunting resolved, her oxygen saturation normalized, and she has resumed jogging. She remains in a complete remission, now fifteen months after her last dose of bortezomib. The second patient, a 55 year old woman, had undergone surgical fenestration of the renal capsule to allow for drainage of the perinephric fluid into her abdomen. The fluid was produced at such a rate that she required regular paracentesis to remove the resulting ascites. She received 6 cycles of intravenous bortezomib. Her telangiectasias resolved, her serum erythropoietin normalized from a peak of 507 mIU/ml, her paO2 improved, and production of perinephric fluid decreased. However, after four months off treatment, the concentration of her IgG kappa paraprotein began to increase, as did her serum erythropoietin. Furthermore, she has developed pulmonary hypertension, which we suspect may represent a rare paraneoplastic condition seen in some patients with multiple myeloma. The third patient, a 52 year old man, has received ten cycles of intravenous bortezomib. He has tolerated therapy well without side-effects. His serum erythropoietin has decreased from 5500 to 2500 mIU/ml. However, he has not shown the same dramatic reduction in the level of his IgG kappa paraprotein, nor has he shown resolution of his telangiectasias, perinephric fluid, or intrapulmonary shunting. The response of the fourth patient to bortezomib was recently described as a letter to the editor in the New England Journal of Medicine. The fifth patient, a 49 year old woman, was referred for evaluation of unexplained and progressive hypoxia requiring the use of continuous supplemental oxygen. She had been diagnosed at age 34 with polycythemia vera and treated with periodic phlebotomy. Telangiectasias were present on the face, chest, abdomen, and back. Erythropoietin was elevated to >8000 mIU/ml and an IgG-kappa paraprotein was identified. Her cardiovascular shunt fraction was 27%. Given the variable response of the other patients to single-agent bortezomib, she began an induction regimen that included cyoclophosphamide, bortezomib, and dexamethasone (CyBorD) with plans for autologous SCT. The efficacy of treatment with bortezomib, as well as the reversible nature of the symptoms, lends support to the hypothesis that the abnormal plasma cell clone and monoclonal gammopathy are the cause of the TEMPI syndrome. Efforts to identify the antigenic target of the paraprotein are underway, using protein microarray and immunohistochemical techniques. We suspect that more patients with the TEMPI syndrome exist. The constellation of the described pentad should raise the potential of this syndrome. We welcome any reader insights into this unusual condition. Disclosures: Raje: Onyx: Consultancy; Celgene: Consultancy; Millennium: Consultancy; Acetylon: Research Funding; Amgen: Research Funding; Eli-Lilly: Research Funding. Somer:BioPat Holdings, Inc.: Consultancy. Off Label Use: We use bortezomib in the treatment of a newly described syndrome, the TEMPI syndrome.

Key points Haemoglobin affinity is an integral concept in exercise physiology that impacts oxygen uptake, delivery and consumption. How chronic alterations in haemoglobin affinity impact physiology is unknown. Using human haemoglobin variants, we demonstrate that the affinity of haemoglobin for oxygen is highly correlated with haemoglobin concentration. Using the Fick equation, we model how altered haemoglobin affinity and the associated haemoglobin concentration influences oxygen consumption at rest and during exercise via alterations in cardiac output and mixed‐venous . The combination of low oxygen affinity haemoglobin and reduced haemoglobin concentration seen in vivo may be unable to support oxygen uptake during moderate or heavy exercise. AbstractThe physiological implications, with regard to exercise, of altered haemoglobin affinity for oxygen are not fully understood. Data from the Mayo Clinic Laboratories database of rare human haemoglobin variants reveal a strong inverse correlation (r = −0.82) between blood haemoglobin concentration and P50, an index of oxygen affinity [Hb = −0.3135(P50) + 23.636]. In the present study, observed P50 values for high, normal and low oxygen‐affinity haemoglobin variants (13, 26 and 39 mmHg) and corresponding haemoglobin concentrations (19.5, 15.5 and 11.4 g dL−1 respectively) are used to model oxygen consumption as a fraction of delivery at rest ( = 0.25 L min−1, cardiac output = 5.70 L min−1) and during exercise ( = 2.75 L min−1, cardiac output = 18.9 l min−1). With high‐affinity haemoglobin, the model shows that normal levels of oxygen consumption can be achieved at rest and during exercise at the assumed cardiac output levels, with reduced oxygen extraction both at rest (16.8% high affinity vs. 21.7% normal) and during exercise (55.8% high affinity vs. 72.2% normal). With low‐affinity haemoglobin, which predicts low haemoglobin concentration, oxygen consumption at rest can be sustained with the assumed cardiac output, with increased oxygen extraction (31.1% low affinity vs. 21.7% normal). However, exercise at 2.75 l min−1 cannot be achieved with the assumed cardiac output, even with 100% oxygen extraction. In conclusion, the model indicates chronic alterations in P50 associate directly with Hb concentration, highlighting that human Hb variants can serve as ‘experiments of nature’ to address fundamental hypotheses on oxygen transport and exercise.

Abstract Pyruvate kinase deficiency (PKD) is the most common enzyme defect of glycolysis and an important cause of hereditary, nonspherocytic hemolytic anemia. The disease has a worldwide geographical distribution but there are no verified data regarding its frequency. Difficulties in the diagnostic workflow and interpretation of PK enzyme assay likely play a role. By the creation of a global PKD International Working Group in 2016, involving 24 experts from 20 Centers of Expertise we studied the current gaps in the diagnosis of PKD in order to establish diagnostic guidelines. By means of a detailed survey and subsequent discussions, multiple aspects of the diagnosis of PKD were evaluated and discussed by members of Expert Centers from Europe, USA, and Asia directly involved in diagnosis. Broad consensus was reached among the Centers on many clinical and technical aspects of the diagnosis of PKD. The results of this study are here presented as recommendations for the diagnosis of PKD and used to prepare a diagnostic algorithm. This information might be helpful for other Centers to deliver timely and appropriate diagnosis and to increase awareness in PKD.

Hereditary erythrocytosis is associated with high oxygen affinity hemoglobin variants (HOAs), 2,3‐bisphosphoglycerate deficiency and abnormalities in EPOR and the oxygen‐sensing pathway proteins PHD, HIF2α, and VHL. Our laboratory has 40 years of experience with hemoglobin disorder testing and we have characterized HOAs using varied protein and molecular techniques including functional assessment by p50 analysis. In addition, we have more recently commenced adding the assessment of clinically relevant regions of the VHL , BPGM, EPOR , EGLN1 (PHD2), and EPAS1 (HIF2A) genes in a more comprehensive hereditary erythrocytosis panel of tests. Review of our experience confirms a wide spectrum of alterations associated with erythrocytosis which we have correlated with phenotypic and clinical features. Through generic hemoglobinopathy testing, we have identified 762 patients with 81 distinct HOA Hb variants (61 β, 20 α), including 12 that were first identified by our laboratory. Of the 1192 cases received for an evaluation specific for hereditary erythrocytosis, approximately 12% had reportable alterations: 85 pathogenic/likely pathogenic mutations and 58 variants of unknown significance. Many have not been previously reported. Correlation with clinical and phenotypic data supports an algorithmic approach to guide economical evaluation; although, testing is expanded if the suspected causes are negative or of uncertain significance. Clinical features are similar and range from asymptomatic to recurrent headaches, fatigue, restless legs, chest pain, exertional dyspnea and thrombotic episodes. Many patients were chronically phlebotomized with reported relief of symptoms.

Deletion of the long arm of chromosome 20 (20q‐) is a frequent finding in bone marrow karyotypes, mainly associated with myeloid neoplasms (MNs). Its clinical significance in the setting of normal bone marrow morphology is unclear. We described the clinical characteristics, cytogenetic findings, and outcome of 102 such patients seen at our institution from 2000‐2014. Their median age was 66 years. The indication for bone marrow biopsy was either unexplained cytopenias (48%) or hematologic cancer staging/reevaluation (52%). In 88 (86%) patients, 20q‐ was an isolated finding. Thirty‐nine (38%) patients previously received chemotherapy and 88 (86%) had cytopenias at the time of 20q‐ finding. After a median of 35 months, 12 (13%) patients developed MNs: 10 myelodysplastic syndromes, one acute myeloid leukemia and one myeloproliferative neoplasm. None of 14 patients with normal blood counts, but 7 of 35 (20%) with mild cytopenias, and 5 of 53 (9%) with moderate/severe cytopenias developed MNs. We did not find an association between the number of metaphases with 20q‐ and the development of MN. The incidental finding of 20q‐ in the bone marrow generally does not portend an early stage MN. Particularly, those without cytopenias at the time of diagnosis may have a good prognosis. Am. J. Hematol. 91:556–559, 2016. © 2016 Wiley Periodicals, Inc.

Abstract Annexin-1 and T-bet are recently described immunohistochemical stains that reportedly assist in the diagnosis of hairy cell leukemia (HCL). Our objective was to assess the sensitivity and specificity of a panel of immunohistochemical stains in distinguishing HCL from other B-cell neoplasms, particularly splenic and extranodal marginal zone lymphomas (SMZL and ENMZL, respectively). The study included 234 bone marrow biopsy specimens: 101 HCL, 13 SMZL, and 10 ENMZL cases were assessed with CD20, tartrate-resistant acid phosphatase (TRAP), DBA.44, a-1, T-bet, and cyclin D1, and 110 control cases were assessed with annexin-1 and T-bet. Our study showed that annexin-1 is a specific and sensitive marker for HCL; however, interpretation is limited by positivity within myeloid precursors. T-bet, DBA.44, and TRAP immunohistochemical stains lack sufficient sensitivity and specificity to differentiate HCL from either form of marginal zone lymphoma. However, our data suggest that the addition cyclin D1 to the immunostaining panel will increase the sensitivity and specificity of HCL diagnosis.

Abstract POEMS is an uncommon syndromic disorder characterized by polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, and skin changes. There are few descriptions of the bone marrow pathology of POEMS; therefore, peripheral blood smears and bone marrow aspirates and biopsies from 87 patients (143 total, 67 pretreatment, 76 posttreatment cases) with POEMS were studied. Plasma cell clonality was analyzed by flow cytometry, immunohistochemistry, and/or in situ hybridization. Monotypic plasma cells were detected in 44 pretreatment cases (66%); the majority of plasma cells expressed λ light chain (91%). The monotypic plasma cells typically were present in a background of increased polytypic plasma cells. Lymphoid aggregates were found in 33 (49%) pretreatment cases and in most cases were rimmed by plasma cells (97%). Megakaryocyte hyperplasia (36 cases) and clusters (62 cases) were frequent; however, none of the 43 cases tested had the JAK2V617F mutation. In summary, we have identified a novel constellation of features that should strongly suggest POEMS syndrome as part of the differential diagnosis. The constellation of λ-restricted monoclonal gammopathy, plasma cell rimming around lymphoid aggregates, and megakaryocytic hyperplasia in a bone marrow is highly suggestive of this diagnosis, especially in the context of a peripheral neuropathy.