Intravenous Administration of Mesenchymal Stem Cell-Derived Exosome Alleviates Spinal Cord Injury by Regulating Neutrophil Extracellular Trap Formation through Exosomal miR-125a-3p.

Spinal cord injury (SCI) leads to devastating sequelae, demanding effective treatments. Recent advancements have unveiled the role of neutrophil extracellular traps (NETs) produced by infiltrated neutrophils in exacerbating secondary inflammation after SCI, making it a potential target for treatment intervention. Previous research has established that intravenous administration of stem cell-derived exosomes can mitigate injuries. While stem cell-derived exosomes have demonstrated the ability to modulate microglial reactions and enhance blood-brain barrier integrity, their impact on neutrophil deactivation, especially in the context of NETs, remains poorly understood. This study aims to investigate the effects of intravenous administration of MSC-derived exosomes, with a specific focus on NET formation, and to elucidate the associated molecular mechanisms. Exosomes were isolated from the cell supernatants of amnion-derived mesenchymal stem cells using the ultracentrifugation method. Spinal cord injuries were induced in Sprague-Dawley rats (9 weeks old) using a clip injury model, and 100 µg of exosomes in 1 mL of PBS or PBS alone were intravenously administered 24 h post-injury. Motor function was assessed serially for up to 28 days following the injury. On Day 3 and Day 28, spinal cord specimens were analyzed to evaluate the extent of injury and the formation of NETs. Flow cytometry was employed to examine the formation of circulating neutrophil NETs. Exogenous miRNA was electroporated into neutrophil to evaluate the effect of inflammatory NET formation. Finally, the biodistribution of exosomes was assessed using 64Cu-labeled exosomes in animal positron emission tomography (PET). Rats treated with exosomes exhibited a substantial improvement in motor function recovery and a reduction in injury size. Notably, there was a significant decrease in neutrophil infiltration and NET formation within the spinal cord, as well as a reduction in neutrophils forming NETs in the circulation. In vitro investigations indicated that exosomes accumulated in the vicinity of the nuclei of activated neutrophils, and neutrophils electroporated with the miR-125a-3p mimic exhibited a significantly diminished NET formation, while miR-125a-3p inhibitor reversed the effect. PET studies revealed that, although the majority of the transplanted exosomes were sequestered in the liver and spleen, a notably high quantity of exosomes was detected in the damaged spinal cord when compared to normal rats. MSC-derived exosomes play a pivotal role in alleviating spinal cord injury, in part through the deactivation of NET formation via miR-125a-3p.

Efficacy and Safety of Single-dose Pegfilgrastim for CD34 + Cell Mobilization in Healthy Volunteers: A Phase 2 Study.

BACKGROUND: Pegfilgrastim, a long-acting form of granulocyte-colony stimulating factor, with a convenient single-injection dosage, is being investigated for peripheral blood stem cell (PBSC) mobilization in healthy volunteers. However, data on the adequate dose of pegfilgrastim for PBSC mobilization are limited. This phase 2, single-arm study evaluated the efficacy and safety of pegfilgrastim for PBSC mobilization in healthy volunteers. METHODS: The study comprised 2 phases: pilot (steps 1-3, dose escalation, a single subcutaneous dose of 3.6, 7.2, and 10.8 mg pegfilgrastim, respectively) and evaluation (step 4, efficacy and safety assessments). The primary endpoint was the proportion of subjects who achieved mobilization of ≥20 × 10 6 /L cluster of differentiation 34 positive (CD34 + ) cells. RESULTS: Thirty-five subjects (6 each in steps 1 and 2 and 23 in step 4) were included. In the pilot phase, step 3 with a 10.8 mg dose was not conducted due to favorable outcomes in step 2 (desired CD34 + cell count), at 7.2 mg pegfilgrastim, which was identified as the optimal dose for the evaluation phase. In the evaluation phase, successful CD34 + mobilization was achieved in all 23 subjects. The mean peripheral blood CD34 + cells count peaked on day 5. Back pain, thrombocytopenia, transient elevations of alkaline phosphatase, and lactate dehydrogenase were the most common adverse events. All adverse events were mild, and none led to study discontinuation. CONCLUSIONS: A single-dose pegfilgrastim successfully mobilized an optimal number of CD34 + cells and was well tolerated. Pegfilgrastim could be an alternative option for PBSC mobilization in healthy volunteers. The trial was registered at www.clinicaltrials.gov (NCT03993639).

Booster effect of a third mRNA-based COVID-19 vaccine dose in patients with myeloid malignancies.

BACKGROUND: We have reported that seroconversion rates after the second dose of mRNA-based COVID-19 vaccines for myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) were 100% and 95% respectively, with no significant difference from healthy controls (HCs).However, there are very limited data for the response to a third vaccine dose in those patients. AIMS: In this complementary study, we investigated the booster effect of a third mRNA-based COVID-19 vaccine dose in patients with myeloid malignancies. MATERIALS & METHODS: A total 58 patients including 20 patients with MDS and 38 patients with AML were enrolled. Anti-SARS-CoV-2S immunoassays were performed at 3, 6, and 9 months after the second vaccine dose. RESULTS: Seventy-five percent of the MDS patients and 37% of the AML patients were receiving active treatment at the time of the third vaccination. Both the initial and third vaccine response in AML patients were comparable to those in HCs. In MDS patients, although the initial vaccine immunogenicity was inferior to that in HCs and AML patients, the third vaccine improved the response to a level not inferior to those in HCs and AML patients. Of note, the third vaccine resulted in a significant increase of antibodies in actively treated MDS patients who had shown a response inferior to that in untreated patients after two doses of vaccination. DISCUSSION: In patients with myeloid malignancies, the third vaccine dose showed a booster effect, and disease- and therapy-related factors associated with the booster response have been identified. CONCLUSION: The third dose of an mRNA-based COVID-19 vaccine showed a booster effect in patients with myeloid malignancies. Such a good booster response has not been reported in other haematological malignancies.

Calcineurin inhibitor inhibits tolerance induction by suppressing terminal exhaustion of donor T cells after allo-HCT.

Calcineurin inhibitor-based graft-versus-host disease (GVHD) prophylaxis is standard in allogeneic hematopoietic stem cell transplantation (HCT) but fails to induce long-term tolerance without chronic GVHD (cGVHD) in a considerable number of patients. In this study, we addressed this long-standing question in mouse models of HCT. After HCT, alloreactive donor T cells rapidly differentiated into PD-1+ TIGIT+ terminally exhausted T cells (terminal Tex). GVHD prophylaxis with cyclosporine (CSP) suppressed donor T-cell expression of TOX, a master regulator to promote differentiation of transitory exhausted T cells (transitory Tex), expressing both inhibitory receptors and effector molecules, into terminal Tex, and inhibited tolerance induction. Adoptive transfer of transitory Tex, but not terminal Tex, into secondary recipients developed cGVHD. Transitory Tex maintained alloreactivity and thus PD-1 blockade restored graft-versus-leukemia (GVL) activity of transitory Tex and not terminal Tex. In conclusion, CSP inhibits tolerance induction by suppressing the terminal exhaustion of donor T cells, while maintaining GVL effects to suppress leukemia relapse.

Safety and efficacy of tisagenlecleucel in patients with relapsed or refractory B-cell lymphoma: the first real-world evidence in Japan.

BACKGROUND: Tisagenlecleucel, an autologous CD19-directed T-cell immunotherapy, can induce a durable response in adult patients with relapsed/refractory (r/r) B-cell lymphoma. METHODS: To elucidate the outcome of chimeric antigen receptor (CAR) T-cell therapy in Japanese, we retrospectively analyzed the outcomes of 89 patients who received tisagenlecleucel for r/r diffuse large B-cell lymphoma (n = 71) or transformed follicular lymphoma (n = 18). RESULTS: With a median follow-up of 6.6-months, 65 (73.0%) patients achieved a clinical response. The overall survival (OS) and event-free survival (EFS) rates at 12 months were 67.0% and 46.3%, respectively. Overall, 80 patients (89.9%) had cytokine release syndrome (CRS), and 6 patients (6.7%) had a grade ≥ 3 event. ICANS occurred in 5 patients (5.6%); only 1 patient had grade 4 ICANS. Representative infectious events of any grade were cytomegalovirus viremia, bacteremia and sepsis. The most common other adverse events were ALT elevation, AST elevation, diarrhea, edema, and creatinine elevation. No treatment-related mortality was observed. A Sub-analysis showed that a high metabolic tumor volume (MTV; ≥ 80 ml) and stable disease /progressive disease before tisagenlecleucel infusion were both significantly associated with a poor EFS and OS in a multivariate analysis (P < 0.05). Notably, the combination of these 2 factors efficiently stratified the prognosis of these patients (HR 6.87 [95% CI 2.4-19.65; P < 0.05] into a high-risk group). CONCLUSION: We report the first real-world data on tisagenlecleucel for r/r B-cell lymphoma in Japan. Tisagenlecleucel is feasible and effective, even in late line treatment. In addition, our results support a new algorithm for predicting the outcomes of tisagenlecleucel.

Humoral response to mRNA-based COVID-19 vaccine and booster effect of a third dose in patients with mature T cell and NK-cell neoplasms.

Patients with lymphoid malignancies have impaired humoral immunity caused by the disease itself and its treatment, placing them at risk for severe coronavirus disease-19 (COVID-19) and reduced response to vaccination. However, data for COVID-19 vaccine responses in patients with mature T cell and NK-cell neoplasms are very limited. In this study of 19 patients with mature T/NK-cell neoplasms, anti-severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) spike antibodies were measured at 3 months, 6 months, and 9 months after the second mRNA-based vaccination. At the time of the second and third vaccinations, 31.6% and 15.4% of the patients were receiving active treatment. All patients received the primary vaccine dose and the third vaccination rate was 68.4%. In patients with mature T/NK-cell neoplasms, both seroconversion rate (p < 0.01) and antibody titers (p < 0.01) after the second vaccination were significantly lower than those in healthy controls (HC). In individuals who received the booster dose, patients had significantly lower antibody titers than those in HC (p < 0.01); however, the seroconversion rate in patients was 100%, which was the same as that in HC. The booster vaccine resulted in a significant increase of antibodies in elderly patients who had shown a response that was inferior to that in younger patients after two doses of vaccination. Since higher antibody titers and higher seroconversion rate reduced the incidence of infection and mortality, vaccination more than three times may have the advantage for patients with mature T/NK-cell neoplasms, especially in elderly patients. Clinical trial registration number: UMIN 000,045,267 (August 26th, 2021), 000,048,764 (August 26th, 2022).

Humoral response to mRNA-based COVID-19 vaccine in patients with immune thrombocytopenia.

Data for COVID-19 vaccine response in patients with immune thrombocytopenia (ITP) are very limited. In a study of 28 patients with ITP, anti-severe acute respiratory syndrome coronavirus 2 spike antibody titres were measured after vaccination. The seroconversion rate for ITP patients was 91.3%, comparable to that in healthy controls (HCs). However, the antibody titre in ITP patients was significantly lower than that in HCs and declined with ageing. Furthermore, the antibody titre in ITP patients who received a minimum prednisolone dose of at least 5 mg/day at any time-point at or after initial vaccination was lower than that in other patients.

Reactive granulopoiesis depends on T-cell production of IL-17A and neutropenia-associated alteration of gut microbiota.

Granulopoiesis in the bone marrow adjusts cellular output as demand for neutrophils changes. Reactive granulopoiesis is induced by profound neutropenia, but its mechanism remains to be clarified. We herein explored its mechanisms using mouse models of syngeneic hematopoietic stem cell transplantation (SCT) and 5-fluorouracil-induced neutropenia. After SCT, T cell production of IL-17A was up-regulated. Neutrophil recovery was significantly delayed in IL-17A-deficient or T cell-deficient RAG1-/- mice, and adoptive transfer of wild-type (WT) T cells facilitated neutrophil engraftment. Gut decontamination with oral antibiotics suppressed T cell production of IL-17A and impaired neutrophil recovery. Transplantation of fecal microbiota collected from neutropenic, not naive, mice promoted neutrophil recovery in these mice, suggesting that neutropenia-associated microbiota had a potential to stimulate reactive granulopoiesis. Our study uncovered a cross talk between gut microbiota and neutropenia after SCT and chemotherapy.

High CRP-albumin ratio predicts poor prognosis in transplant ineligible elderly patients with newly diagnosed acute myeloid leukemia.

Acute myeloid leukemia (AML) patients older than 65 years have a poor prognosis. Recently, CAR (C-reactive-protein/albumin ratio) has been actively reported as a prognostic index reflecting the nutritional and inflammatory status of elderly patients with solid tumors, but the usefulness of this index as a prognostic indicator in transplant-ineligible elderly AML patients has not been investigated. We studied genetic alterations and CARs in 188 newly diagnosed AML patients aged 65 years or older who were treated in a multicenter setting and had treated without HSCT. Both NCCN 2017 risk group, reflecting the genetic component of the tumor, and CAR, reflecting the inflammatory and nutritional status of the patient, successfully stratified the overall survival (OS) of the patients (2-year OS; CAR low vs high, 42.3% vs 17.8%, P < 0.001). Furthermore, in multivariate analysis, NCCN 2017 poor group and high CAR were extracted as independent poor prognostic factors predicting 2-year OS in the current study. We found, for the first time, that CAR at diagnosis predicted the prognosis of elderly patients with newly diagnosed AML treated without HSCT.

Dynamic change in peripheral blood WT1 mRNA levels within three cycles of azacitidine predict treatment response in patients with high-risk myelodysplastic syndromes.

Azacitidine (AZA) improves overall survival (OS) in patients with high-risk myelodysplastic syndromes (MDS). However, predictive factors for response to AZA remain largely unknown. To elucidate whether dynamic change in peripheral blood (PB) Wilms' Tumor 1 (WT1) mRNA levels could predict response to AZA, we retrospectively identified 75 treatment-naïve patients with high-risk MDS who received at least 3 cycles of AZA. We classified patients into 4 groups, low-increase (LI), low-stable (LS), high-decrease (HD), and high-stable (HS) based on the dynamic change in PB WT1 mRNA levels within 3 cycles of AZA. Cumulative incidence of overall response after 10 cycles of AZA was significantly higher in LS/HD than in HS/LI (75.5% vs 4.5%, P < 0.001). The median OS for LS/HD was 18.2 months (95% CI, 12.8-28.1 months), whereas it was 11.6 months for HS/LI (95% CI, 6.6-14.1 months; P < 0.001). Multivariate analysis demonstrated that poor-/very poor-IPSS-R cytogenetic risk and HS/LI were independently associated with poor OS (poor-/very poor-IPSS-R cytogenetic risk: HR, 2.26; 95% CI, 1.10-4.68, P = 0.03, HS/LI: HR, 2.32; 95% CI, 1.21-4.46, P = 0.01). Patients with HS/LI did not show any further response to continuous AZA, and they should be considered for alternative therapy from earlier cycles.

Gilteritinib enhances graft-versus-leukemia effects against FLT3-ITD mutant leukemia after allogeneic hematopoietic stem cell transplantation.

Allogeneic hematopoietic stem cell transplantation (allo-SCT) is a potentially curative therapy for FLT3 internal tandem duplication mutant (FLT3-ITD+) acute myeloid leukemia, but relapse rate is high. A recent study showed that sorafenib, a first generation FLT3 and multikinase inhibitor, enhanced graft-versus-leukemia (GVL) effects against FLT3-ITD+ leukemia via interleukin-15 (IL-15) production. However, it remains to be clarified whether this effect could be mediated by selective FLT3 inhibition. We investigated whether gilteritinib, a selective FLT3 inhibitor, could enhance GVL effects against FLT3-ITD transfected Ba/F3 leukemia (Ba/F3-FLT3-ITD) in mice. Oral administration of gilteritinib from day +5 to +14 after allo-SCT reduced expression of the co-inhibitory receptors PD-1 and TIGIT on donor CD8+ T cells and enhanced IL-15 expression in Ba/F3-FLT3-ITD. Bioluminescent imaging using luciferase-transfected Ba/F3-FLT3-ITD demonstrated that gilteritinib significantly suppressed leukemia expansion after allo-SCT, whereas it did not impact the morbidity or mortality of graft-versus-host disease (GVHD), resulting in significant improvement of overall survival. In conclusion, short-term administration of gilteritinib after allo-SCT enhanced GVL effects against FLT3-ITD+ leukemia without exacerbating GVHD.

A novel nutritional index "simplified CONUT" and the disease risk index independently stratify prognosis of elderly patients with acute myeloid leukemia.

Elderly patients aged 65 or older with acute myeloid leukemia (AML) have poor prognosis. The risk stratification based on genetic alteration has been proposed in national comprehensive cancer network (NCCN) guideline but its efficacy was not well verified especially in real world elderly patients. The nutritional status assessment using controlling nutritional status (CONUT) score is a prognostic biomarker in elderly patients with solid tumors but was not examined in elderly AML patients. We performed prospective analysis of genetic alterations of 174 patients aged 65 or older with newly diagnosed AML treated without hematopoietic stem cell transplantation (HSCT) and developed simplified CONUT (sCONUT) score by eliminating total lymphocyte count from the items to adapt AML patients. In this cohort, both the NCCN 2017 risk group and sCONUT score successfully stratified the overall survival (OS) of the elderly patients. A multivariable analysis demonstrated that adverse group in NCCN 2017 and high sCONUT score were independently associated with poor 2-year OS. Both risk stratification based on NCCN 2017 and sCONUT score predict prognosis in the elderly patients with newly diagnosed AML.

High metabolic heterogeneity on baseline 18FDG-PET/CT scan as a poor prognostic factor for newly diagnosed diffuse large B-cell lymphoma.

Metabolic heterogeneity (MH) can be measured using 18F-fluorodeoxyglucose (18FDG) positron emission tomography/computed tomography (PET/CT), and it indicates an inhomogeneous tumor microenvironment. High MH has been shown to predict a worse prognosis for primary mediastinal B-cell lymphoma, whereas its prognostic value in diffuse large B-cell lymphoma (DLBCL) remains to be determined. In the current study, we investigated the prognostic values of MH evaluated in newly diagnosed DLBCL. In the training cohort, 86 patients treated with cyclophosphamide, doxorubicin, vincristine, and prednisone-like chemotherapies were divided into low-MH and high-MH groups using receiver operating characteristic analysis. MH was not correlated with metabolic tumor volume of the corresponding lesion, indicating that MH was independent of tumor burden. At 5 years, overall survivals were 89.5% vs 61.2% (P = .0122) and event-free survivals were 73.1% vs 51.1% (P = .0327) in the low- and high-MH groups, respectively. A multivariate Cox-regression analysis showed that MH was an independent predictive factor for overall survival. The adverse prognostic impacts of high MH were confirmed in an independent validation cohort with 64 patients. In conclusion, MH on baseline 18FDG-PET/CT scan predicts treatment outcomes for patients with newly diagnosed DLBCL.

Salvage Transplantation with Cord Blood for Graft Rejection of Peripheral Blood Stem Cells due to Donor Specific Antibody.

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative therapy for various kinds of hematological malignancies and disorders. Recently, HLA-haploidentical stem cell transplantation with post-transplantation cyclophosphamide (PTCy-haplo HSCT) has been widely performed due to its safety and favorable immune recovery. However, graft rejection remains an obstacle to PTCy-haplo HSCT. Donor specific antibody (DSA) is considered to be a major factor of graft rejection of haplo HSCT. We herein present a case of graft rejection after PTCy haplo-HSCT due to DSA induced by pretransplant platelet transfusion after donor selection. The patient was dependent on platelet transfusion and had not received cytotoxic chemotherapy because he was diagnosed as myelodysplastic syndrome/myeloproliferative neoplasm-unclassifiable. We retrospectively confirmed the level of DSA just before the first transplantation and found that it was dramatically elevated, which was enough to cause graft rejection. We successfully performed cord blood transplantation of the HLA that was not the target of DSA, as salvage transplantation without any desensitization. This case illustrates that we have to confirm the presence of DSA immediately before the haplo-HSCT, particularly in high risk patients who are dependent on platelet transfusion and have no cytotoxic chemotherapy before HSCT.

Serum level of soluble interleukin-2 receptor is positively correlated with metabolic tumor volume on 18 F-FDG PET/CT in newly diagnosed patients with diffuse large B-cell lymphoma.

Diffuse large B-cell lymphoma (DLBCL) is the most frequent subtype of non-Hodgkin lymphoma. High total metabolic tumor volume (TMTV) calculated using 18 F-FDG PET/CT images at diagnosis predicts poor prognosis of patients with DLBCL. However, high cost and poor access to the imaging facilities hamper wider use of 18 F-FDG PET/CT. In order to explore a surrogate marker for TMTV, we evaluated the correlation between the serum levels of soluble interleukin-2 receptor (sIL-2R) and TMTV in 64 patients with DLBCL, and the results were verified in an independent validation cohort of 86 patients. Serum levels of sIL-2R were significantly correlated with TMTV. ROC analysis revealed that the cutoff value of TMTV ≥150 cm3 or sIL-2R ≥ 1300 U/mL could predict failure to achieve EFS24 with areas under the curve (AUC) 0.706 and 0.758, respectively. Each of TMTV ≥150 cm3 and sIL-2R ≥1300 U/mL was significantly associated with worse 5-year overall survival and event-free survival. Importantly, each of sIL-2R <1300 U/mL or TMTV <150 cm3 identified patients with favorable prognosis among NCCN-IPI high-intermediate and high-risk group. Serum level of sIL-2R represents a convenient surrogate marker to estimate metabolic tumor burden measured by 18 F-FDG PET/CT that can predict treatment outcomes of patients with DLBCL.

Acquired hemophilia A developing cerebral infarction 36 days after the frequent administration of bypass hemostatic agents.

A 74-years-old male who was a smoker and received treatment for hypertension, dyslipidemia, peripheral arterial disease and idiopathic interstitial pneumonia complained of subcutaneous hemorrhage of the right lower thigh. Marked anemia (hemoglobin 5.5 g/dL) and prolonged activated partial thromboplastin time (≥130 seconds) were noted. The factor VIII activity level was reduced to 1.2%, and the factor VIII inhibitor titer was 285.3 BU/mL, a diagnosis of acquired hemophilia A (AHA) was made. Then, hematomas of 5 intra-muscles were recurred. Hemostasis became difficult despite frequent and high-dose administration of recombinant human coagulation factor VIIa (total: 18 days, 305 mg). Hemostasis was achieved by switching to activated prothrombin complex concentrate (for 3 days, 18,000 units), however, cerebral infarction occurred after 36 days. After the frequent administration of bypass hemostatic agents on elderly AHA patients with several risk factors for ischemic stroke, the risk of subsequent thrombotic events may persist for 1 month.

Hyperferritinemia: causes and significance in a general hospital.

OBJECTIVE: To elucidate conditions which cause elevation of the serum ferritin, extent of the elevation in each condition, and clinical relevance of hyperferritinemia in general practice. METHODS: We retrospectively studied medical records of all patients who had at least one serum ferritin measurement above 500 µg L-1. Patients who had a marked elevation of the serum ferritin over 10,000 µg L-1 were studied separately. RESULTS: We studied 1394 patients to identify the etiologies of hyperferritinemia. Median serum ferritin level was 1024 µg L-1 and 49.2% had ferritin levels of 501-1000 µg L-1. The most frequent cause of hyperferritinemia was non-human immunodeficiency virus infection followed by solid tumor, liver dysfunction, renal failure, and hematological malignancy. The distributions of the causes were different among groups stratified by the ferritin level. Forty-one percent had multiple causes and there was a tendency that the more underlying causes a patient had, the higher the ferritin level. Each condition led to a wide range of the ferritin level, and some patients could present with marked hyperferritinemia. Seventy percent of 111 patients with marked hyperferritinemia had multiple etiologies and a variety of diseases could lead to marked hyperferritinemia by themselves. DISCUSSION: Patients with hyperferritinemia frequently had multiple conditions. The level of the serum ferritin was determined by the underlying conditions to a certain extent; however, the variation was significant. While patients with marked hyperferritinemia mostly had multiple underlying causes, various diseases could cause hyperferritinemia by themselves. CONCLUSION: Hyperferritinemia is associated with both etiology and the number of underlying causes.

Simultaneous Presentation of Giant Cell Arteritis and Myelodysplastic Syndrome in an Elderly Japanese Man.

An 81-year-old Japanese man presented with constitutional symptoms and anemia and was diagnosed with giant cell arteritis (GCA) and myelodysplastic syndrome (MDS) simultaneously. His symptoms and anemia improved promptly with steroids; however, the MDS rapidly progressed to overt leukemia. While MDS patients are at an increased risk of autoimmune diseases, an association with GCA has rarely been reported. This case illustrates the importance of considering GCA as a cause of anemia in elderly patients if MDS is already diagnosed, even in countries where the prevalence of GCA is very low. The simultaneous development of GCA and MDS suggests a common pathogenetic link between these two diseases.