Exacerbation of autoimmune hemolytic anemia associated with pure red cell aplasia after COVID-19: A case report

Autoimmune hemolytic anemia (AIHA) and pure red cell aplasia (PRCA) are rare complications of coronavirus disease 2019 (COVID-19). Herein, we report the case of a 28-year-old Japanese man who showed severe AIHA exacerbation associated with PRCA after COVID-19. AIHA was diagnosed and maintained for 5 years. Approximately 4 weeks after COVID-19, the patient developed severe anemia (hemoglobin level, 3.4 g/dL). Laboratory test results confirmed hemolytic exacerbation of IgG-mediated warm-type AIHA. Despite the hemolysis phase, the bone marrow revealed extreme hypoplasia of erythroblasts with a decreased reticulocyte count, similar to that observed in patients with PRCA. During oral prednisolone treatment, the patient recovered from anemia and showed increased reticulocyte count and reduced hypoplasia of marrow erythroblasts. Exacerbation of AIHA and PRCA was triggered by COVID-19 because other causes were ruled out. Although this case report highlights that COVID-19 could lead to hematological complications such as AIHA and PRCA, the exact mechanisms remain unclear.     

Pure red cell aplasia caused by parvovirus B19 in two patients without chronic hemolysis

Infection with human parvovirus B19 (PVB19) induces acquired pure red cell aplasia (PRCA). Chronic hemolytic anemia is well known as an underlying condition. However, additional factors have been recognized to accompany parvoviral PRCA; however, there are only limited reports on iron-deficiency anemia (IDA) and rituximab-induced B-cell dysfunction. We report two patients with PVB19-associated PRCA confirmed by positivity of viral DNA. Although they had no chronic hemolysis, patient 1 had IDA, and patient 2 had remitted small-lymphocytic lymphoma treated with rituximab-containing chemotherapy. Absence of reticulocytes in peripheral blood and marked depletion of erythroid precursors in bone marrow were observed both. Whereas patient 1 received only symptomatic therapy because anemia was not severe, patient 2 was treated with steroids, as PRCA etiology was at first uncertain, and immunological PRCA was not excluded. Both showed rapid increase of reticulocyte counts and recovery from anemia. Although immunoglobulin is considered effective for parvoviral PRCA, notable adverse reactions have been reported. When anemic symptom is not severe, reticulocyte observation only is recommended. The effects of steroids should also be re-evaluated. Optimal treatment according to disease severity remains to be established.     

口服环磷酰胺治疗难治性T细胞大颗粒淋巴细胞白血病合并纯红细胞再生障碍性贫血的疗效

目的:探讨小剂量环磷酰胺口服治疗难治性T-大颗粒淋巴细胞白血病(T-LGLL)伴纯红细胞再生障碍性贫血(PRCA)的疗效。方法:报告1例T-LGLL合并PRCA患者的临床表现、实验室检查特征,及应用环孢素A联合强的松无效后给予口服小剂量环磷酰胺的治疗经过,并结合文献进行讨论。结果:患者为老年女性,临床进展缓慢,以贫血为主要表现,骨髓红系细胞增生显著低下,血涂片以大颗粒淋巴细胞为主,免疫分型及基因重排符合T-LGLL,应用环孢素A联合强的松治疗5个月无效,需要依赖反复输血。二线改用环磷酰胺100 mg/d口服,血红蛋白恢复至正常水平,停药1年仍维持疗效。结论:T-LGLL合并PRCA少见,小剂量环磷酰胺可作为有效的治疗方案。     

Immune reconstitution to parvovirus B19 and resolution of anemia in a patient treated with highly active antiretroviral therapy

Immune reconstitution inflammatory syndrome (IRIS) is an unsolved problem in the treatment of human immunodeficiency virus (HIV)-1 infection. Despite the high seroprevalence of parvovirus B19 (PVB19) among HIV-1-positive patients, reports on PVB19-induced anemia, especially that associated with PVB19-related IRIS, in these patients are limited. We present the case of a man with acquired immunodeficiency syndrome who developed severe transfusion-dependent anemia and was seropositive and borderline positive for immunoglobulin-M and IgG antibodies against PVB19, respectively. PVB19-DNA was also detected in his serum. The patient was diagnosed with pure red cell anemia (PRCA) caused by a primary PVB19 infection and was treated with periodical blood transfusions. However, he subsequently tested negative for IgG antibodies and developed chronic severe anemia with high levels of PVB19 viremia. This indicated a transition from primary to persistent infection. After initiation of highly active antiretroviral therapy, the patient showed an inflammatory reaction with rapid deterioration of anemia and seroconversion of the IgG antibody to PVB19. Subsequently, PRCA was completely resolved, but the patient’s serum still contained low levels of PVB19-DNA. Thus, this was a case of IRIS associated with PVB19 infection. Our report highlights the significance of seroconversion to PVB19 in the diagnosis of IRIS and re-emphasizes the finding that persistently high levels of PVB19 viremia after primary infection are probably because of the lack of protective antibodies.     

A clinical review of antibody-mediated pure red cell aplasia.

Pure red cell aplasia (PRCA) is a rare hematologic disorder characterized by severe anemia from selectivefailure of the bone marrow to produce mature red blood cells. This disorder can be congenital or acquired from various causes. The development of PRCA in patients with chronic kidney disease receiving recombinant erythropoietin (rHuEPO) for renal anemia has increased in recent years. This review will enable nurses to recognize the pathogenesis, clinical manifestations, and therapeutic options for rHuEPO-induced PRCA.     

重组人促红细胞生成素致纯红细胞再生障碍性贫血5例临床观察

目的观察重组人促红细胞生成素致纯红细胞再生障碍性贫血(PRCA)患者经激素/环孢素干预的临床疗效。方法回顾性分析2008年4月至2011年4月在吉林大学第二医院血液净化中心透析且明确诊断为PRCA的5例患者,给予激素/环孢素干预,并观察用药前后贫血纠正情况、用药情况及临床疗效。结果 5例患者中2例单独使用足量激素干预有效,2例无效患者将激素减至中等剂量并加用环孢素后贫血改善。此4例患者血红蛋白维持在70-90g/L不再继续上升,重新应用促红细胞生成素后血红蛋白恢复到正常水平。该4例患者在停用激素/环孢素后随访8个月以上未复发。另一例(病例5)患者口服激素45mg/日,应用3个月后无效,换用环孢素,贫血得到初步改善,未应用促红细胞生成素,血红蛋白维持在70-80g/L。结论足量激素对部分患者有效,部分无效患者加用环孢素能够有效改善贫血,在病情得到稳定控制后,可加用促红细胞生成素进一步纠正贫血。     

First case of convalescent plasma transfusion in a child with COVID-19-associated severe aplastic anemia

We present the case of a six-year-old girl with severe COVID-19, in whom SARS-CoV-2 was successfully eliminated after convalescent plasma transfusion. Children show a variable clinical course of COVID-19, from asymptomatic to critical. In our patient, we diagnosed COVID-19-associated aplastic anemia with severe pancytopenia. The correlation between SARS-CoV-2 infection with aplastic anemia remains unclear. At the beginning of the disease, we used antiviral drugs and immune modulators as therapy but without any positive results. After providing a transfusion of convalescent plasma, the elimination of SARS-CoV-2 was observed. We did not observe any adverse events of this treatment. The girl still has a diagnosis of aplastic anemia and requires specialist therapy.     

Hypersensitivity syndrome and pure red cell aplasia following allopurinol therapy in a patient with chronic kidney disease

OBJECTIVE: To report a rare case of combined hypersensitivity syndrome and pure red cell aplasia (PRCA) following allopurinol therapy. CASE SUMMARY: A 43-year-old woman with underlying mesangioproliferative glomerulonephritis developed fever, generalized morbilliform rash, leukocytosis with marked eosinophilia, and hepatic dysfunction 3 weeks after starting allopurinol therapy (300 mg/day for 3 days followed by 200 mg/day) for hyperuricemia and arthritis. The clinical findings were judged to be a probable drug reaction according to the Naranjo probability scale. The drug-induced hypersensitivity syndrome (DHS) resolved after withdrawal of allopurinol and initiation of systemic corticosteroid therapy. However, there was progressive worsening of anemia with reticulocytopenia; PRCA was suspected. PRCA was judged to be a possible drug reaction according to the Naranjo probability scale. The patient refused blood transfusion and bone marrow biopsy. Recombinant human erythropoietin was initiated in addition to prednisolone 15 mg daily. Eleven days later (approximately 7 wk after allopurinol withdrawal), both the hemoglobin level and reticulocyte count began to rise. The patient consented to a bone marrow study at that time, which confirmed the presence of dysplasia involving only the erythroid lineage. DISCUSSION: Allopurinol may induce DHS, aplastic anemia, and, in rare instances, PRCA. We report the first case of PRCA concurrent with allopurinol-induced DHS in a patient with chronic kidney disease. Discontinuation of allopurinol is the first step in the treatment of such cases. The slow recovery of PRCA might be partly attributed to her underlying chronic kidney disease. CONCLUSIONS: To minimize serious DHS, proper indications for treatment and dosage adjustment should be closely observed when starting allopurinol therapy in patients with chronic kidney disease.     

伴有自身免疫性溶血性贫血及纯红系再生障碍性贫血的血管免疫母细胞性T细胞淋巴瘤

血管免疫母细胞性T细胞淋巴瘤（AITL）是一种外周T细胞淋巴瘤,常合并自身免疫现象,如免疫相关性血细胞减少症,是NHL中的少见类型。为了研究AITL的临床特征,病理表现和有效的治疗方法,对1例37岁男性患者进行了血常规检查、骨髓检测、单个核细胞的流式细胞术检测、Coombs试验、血清学检测、CT和免疫组织化学测定等。结果查明,患者有广泛淋巴结肿大、肝脾肿大,颈部淋巴结活检表明为血管免疫母细胞性T细胞淋巴瘤;患者重度贫血,网织红细胞降低,Coombs实验阳性,骨髓红系增生低下,提示并发温抗体型自身免疫性溶血性贫血（AIHA）和纯红系再生障碍性贫血（PRCA）;经过CHOP-E方案化疗后,合并的AIHA和PRCA以及AITL浸润症状均消失。结论：成功地确诊了合并有AIHA和PRCA的AITL,淋巴结活检和骨髓检测意义大,CHOP-E化疗方案对此种AITL有一定治疗效果。     

T细胞大颗粒淋巴细胞白血病合并纯红细胞再生障碍的临床特征

目的 提高对T细胞大颗粒淋巴细胞白血病(T-LGLL)合并纯红细胞再生障碍(PRCA)的认识.方法 回顾性分析我院2000年1月至2006年8月间确诊的T-LGLL合并PRCA患者临床及实验室检查特征.结果14例T-LGLL合并PRCA患者中男7例,女7例,中位年龄61岁.患者呈慢性病程,主要表现贫血症状,9例患者脾脏轻、中度肿大,1例患者同时伴轻度肝脏肿大,1例患者浅表淋巴结肿大.初诊时患者中位Hb 61.5 g/L,中位WBC 4.30(2.70～7.95)×109/L,中位淋巴细胞比例0.59(0.30～0.87),外周血大颗粒淋巴细胞中位比例和中位绝对值分别为0.36(0.14～0.77)和1.9(0.4～4.5)×109/L,骨髓有核细胞中大颗粒淋巴细胞中位比例0.165(0.085～0.410).部分患者血清学检查异常.12例患者常规染色体检查无异常.给予环孢素和(或)糖皮质激素为主的免疫抑制治疗,患者总有效率91%.结论 合并PRCA的T-LGLL患者临床及实验室特征与经典T-LGLL者相似,以贫血为突出表现,脾脏肿大多见.外周血白细胞正常或减少,大颗粒淋巴细胞相对增多.对免疫抑制治疗反应良好.     

Pure red cell aplasia and myelofibrosis in B-cell neoplasm

We describe an unusual case of B-cell neoplasm accompanied by pure red cell aplasia (PRCA) and myelofibrosis in a 67-year-old male presenting with severe anaemia. A few unclassified, myeloperoxidase-negative blastoid cells were seen on bone marrow aspiration, and erythroid cell hypoplasia and myelofibrosis on bone marrow biopsy. An autoimmune PRCA was suspected, as serum CH50, C3 and C4 levels were consistently low. Ciclosporin was effective in treating the anaemia, but anaemia returned when the drug was discontinued. Thirteen months later, the patient was admitted with pleural effusion and ascites that contained monoclonal CD19+ CD20+ immature blast cells with a complex karyotype, thought to be neoplastic B-cells. The unclassified blastoid cells seen earlier may therefore have been from the same origin. The patient deteriorated rapidly and died. Only one case of non-Hodgkin's lymphoma with PRCA and myelofibrosis has been reported previously. We discuss the possibility that dysregulated T-cells induced by neoplastic B-cells may have given rise to concomitant PRCA and myelofibrosis.     

获得性纯红细胞再生障碍性贫血患者的T淋巴细胞亚群分析及疗效观察

目的 探讨获得性纯红细胞再生障碍性贫血(PRCA)患者的T淋巴细胞亚群分布和外周血、骨髓中大颗粒淋巴细胞(LGL)绝对细胞数及比例,评估获得性PRCA患者的免疫功能状态与免疫抑制剂疗效.方法 选取2002年1月至2015年11月于新疆维吾尔自治区人民医院血液科住院治疗的25例初诊获得性PRCA患者为研究对象,纳入研究组.其中,5例患者为T细胞型大颗粒淋巴细胞白血病(T-LGLL)继发PRCA,其余20例为原发性PRCA.研究组患者纳入标准:符合《血液病诊断及疗效标准》中有关获得性PRCA的诊断标准;临床资料完整.排除标准:其他具有贫血表现的疾病;临床资料不全者.采用简单随机抽样法选择同期于本院体检中心进行体检的25例健康个体纳入对照组.对照组受试者纳入标准:血常规检查、生化检查结果均在正常参考值范围者.排除标准:血常规检查结果异常及罹患免疫性疾病、肿瘤者.采用流式细胞术对两组受试者进行T淋巴细胞亚群检测;对研究组获得性PRCA患者于治疗前、后进行血常规及骨髓检查;对研究组获得性PRCA患者的骨髓、外周血中LGL绝对细胞数及比例结果和环孢素A等药物治疗疗效进行回顾性分析,并进行统计学比较.本研究遵循的程序符合新疆维吾尔自治区人民医院人体试验委员会所制定的伦理学标准,得到该委员会批准.两组受试者年龄、性别构成比等一般临床资料相比,差异均无统计学意义(P＞0.05).结果 ①研究组获得性PRCA患者的辅助性T淋巴细胞(Th)比例、Th/抑制性T淋巴细胞(Ts)值均低于对照组,Th比例:(36.6土3.8)％比(45.1±2.1)％,Th/Ts值:1.2±0.2比2.2土0.4,并且差异均有统计学意义(t=9.161、12.174,P=0.032、0.021).研究组Ts比例高于对照组,分别为(30.5±2.8)％比(20.2±1.9)％,并且差异亦有统计学意义(t=13.460,P=0.021).两组自然杀伤(NK)细胞比例相比,分别为(11.3士1.8)％比(10.3±1.3)％,差异无统计学意义(t=1.572,P=0.344).研究组中,5例T-LGLL继发PRCA患者的Th比例、Th/Ts值均低于其余20例原发性PRCA患者,Th比例:(36.1±3.7)％比(39.1±6.1)％,Th/Ts值:1.0土0.2比1.2±0.1,但差异却均无统计学意义(t=2.293、2.513,P=0.301、0.297);5例T-LGLL继发PRCA患者的Ts比例则高于其余20例原发性PRCA患者,分别为(31.0±2.7)％比(28.4±2.0)％,但差异无统计学意义(t=1.472,P=0.384);T-LGLL继发PRCA患者的NK细胞比例与其余20例原发性PRCA患者相比,分别为(11.3±1.8)％比(11.1％±2.7)％,差异亦无统计学意义(t=1.572,P=0.364).②研究组中,外周血淋巴细胞比例增高患者为16例(64％,16/25),其中有2～3颗粗大颗粒的LGL者为10例(40％,10/25);LGL占淋巴细胞总数20％以上者为8例(32％,8/25).研究组中,骨髓有2～3颗粗大颗粒LGL患者为4例(16％,4/25),LGL占淋巴细胞总数20％以上者为3例(12％,3/25).研究组25例获得性PRCA患者外周血检出LGL比例较骨髓中检出比例高,并且差异有统计学意义(x2=6.595,P=0.003).③治疗后,25例获得性PRCA患者中血常规检查结果恢复至正常参考值范围患者为18例,其中4例患者的骨髓检查结果亦恢复至正常参考值范围,另14例患者骨髓检查结果显示红系细胞增生程度仍减低,但较治疗前有所增高.研究组疗效评价结果显示,获得基本治愈的获得性PRCA患者为4例,获得缓解者为14例,获得明显进步者为6例,无效者为1例;治疗总有效率为96％(24/25).5例T-LGLL继发PRCA患者治疗后脱离输血,但不同于原发性PRCA患者,其血红蛋白(Hb)水平均未恢复至正常参考值范围内.结论 获得性PRCA患者T淋巴细胞亚群比例失调导致其细胞免疫功能紊乱,外周血检出LGL对获得性PRCA的诊断具有一定意义.环孢素A治疗对于获得性PRCA疗效显著,但对T-LGLL继发PRCA患者的疗效差于原发性PRCA患者.     

Aplastic anemia and pure red cell aplasia

Aplastic anemia (AA) is a disorder characterized by the presence of pancytopenia and a hypocellular bone marrow. Acquired pure red cell aplasia (PRCA), a part of a unique form of AA, is a rare condition of profound anemia characterized by the absence of reticulocytes and the virtual absence of erythroid precursors in the bone marrow. AA can be effectively treated by either stem cell transplantation or immunosuppressive therapy. However, PRCA has so far been treated by several different regimens which are largely empirically selected since so little control data are available. This issue focuses on the current progress in the treatment of acquired AA and PRCA.     

Post-COVID-19 vaccination arm pain diagnosed as complex regional pain syndrome: A case report

As the vaccination efforts against the coronavirus disease-2019 (COVID-19) continue, more patients are likely to present with complications related to COVID-19 vaccination. We describe the first reported case of complex regional pain syndrome (CRPS), involving the upper extremities, that occurred after COVID-19 vaccination. The patient presented with acute-onset severe arm pain and swelling following vaccine administration. Based on the clinical, electrodiagnostic, and radionuclide three-phase bone scan findings, the patient was diagnosed with postvaccination CRPS. The COVID-19 vaccine possibly elicited an immune-mediated inflammatory response to the injected antigen in the patient, who was predisposed to CRPS due to inflammatory immunity. The COVID-19 vaccine elicited an immune-mediated inflammatory response to the injected antigen, resulting in CRPS following COVID-19 vaccination.     

获得性纯红细胞再生障碍性贫血的细胞免疫发病机制的研究进展

纯红细胞再生障碍性贫血是以骨髓单纯红系造血衰竭或紊乱为特征的一组导质性疾病，分为先天性和获得性两类。细胞免疫介导的红系造血损伤可能是获得性纯红细胞再生障碍性贫血的主要发病机制。本就近年来关于获得性纯红细胞再生障碍性贫血的T细胞异常、T细胞亚群改变、异常T细胞的克隆性以及细胞因子在发病过程中所起的作用做一综述。     

Epstein–Barr-virus-associated hepatitis with aplastic anemia: A case report

ABSTRACT BACKGROUND Hepatitis-associated aplastic anemia (HAAA) is a rare condition. Patients with HAAA usually present with acute hepatitis, jaundice and significantly increased transaminase. After 1–2 mo, hepatitis gradually improves, but progressive hemocytopenia, bone marrow hematopoietic failure, and severe or extremely severe aplastic anemia are manifest. Most cases of HAAA are fulminant and usually lethal if left untreated. The literature on Epstein–Barr virus (EBV)-associated HAAA is sparse. CASE SUMMARY We report a 30-year-old man who was admitted to our hospital because of pale yellow urine and skin with a simultaneous decrease in peripheral blood ternary cells. We made a diagnosis of EBV-associated HAAA. The treatment strategy for this patient included eltrombopag, an immunosuppressive regimen of rabbit anti-human thymocyte immunoglobulin, cyclosporine, and supportive care. The patient was discharged in normal physical condition after five months. A hemogram performed on follow-up revealed that he had achieved a complete response. CONCLUSION Eltrombopag plus anti-thymocyte globubin and cyclosporine may be a therapeutic option for EBV-associated HAAA.Larger studies are warranted to confirm.     

抗T淋巴细胞单克隆抗体对重型再生障碍性贫血造血祖细胞的影响

报告抗Ｔ淋巴细胞单克隆抗体（ＭｃＡｂ－Ｔ）对重型再生障碍性贫血（ＳＡＡ）造血祖细胞的影响。发现经ＭｃＡｂ－Ｔ体外清除（ＳＡＡ）骨髓中的ＣＤ＿３或ＣＤ＿８细胞后，１９例ＳＡＡ中有１０例患者的粒－单核系祖细胞集落及红系祖细胞集落产量明显增多（Ｐ＜０．０１）。提示部分ＳＡＡ的发病与Ｔ淋巴细胞的免疫抑制有关。在体内应用ＭｃＡｂ－Ｔ（抗ＣＤ＿３和抗ＣＤ＿８）治疗后，该１０例患者临床疗效显著，其中基本治愈、缓解共６例，明显进步４例。结果表明，ＭｃＡｂ－Ｔ能特异性地抑制相应的Ｔ淋巴细胞，解除Ｔ淋巴细胞对造血功能的直接或间接抑制作用，从而使ＳＡＡ患者的造血功能得以恢复。     

环磷酰胺联合环孢霉素介导的获得性再生障碍性贫血小鼠模型的建立

目的:建立较稳定的获得性再生障碍性贫血小鼠模型。方法:雌性6月龄BALB/C小鼠经连续14 d腹腔注射环磷酰胺和环孢霉素后,观察其外周血三系细胞数、血红蛋白浓度以及骨髓有核细胞数量、骨髓涂片、骨髓病理切片等指标。结果:经腹腔注射环磷酰胺和环孢霉素的BALB/C小鼠外周血三系细胞数及血红蛋白浓度均显著减少,其中白细胞、血小板表现得尤为明显;骨髓涂片示骨髓有核细胞数量明显下降,骨髓增生低下;骨髓病理切片示造血细胞减少,脂肪细胞等非造血细胞增多。结论:通过环磷酰胺联合环孢霉素腹腔注射的小鼠模型,其各项检测指标均达到获得性再生障碍性贫血的诊断标准,可作为获得性再生障碍性贫血发病机制及治疗研究的小鼠模型。     

Surgically treated reactive arthritis of the ankle after COVID-19 infection: A case report

A 37-year-old man developed right ankle pain and swelling six days after being diagnosed with coronavirus disease (COVID-19). Despite conservative treatment, his ankle symptoms persisted. Magnetic resonance imaging and computed tomography showed synovial hypertrophy and bone erosion in the ankle. Following arthroscopic synovectomy, performed 69 days after the COVID-19 diagnosis, the pain improved significantly. The clinical course was consistent with that of reactive arthritis following severe acute respiratory syndrome coronavirus 2 infection. The pathological findings resembled rheumatoid nodules. The bone erosion may have originated from the inflammatory pathway, which resembles the mechanism of rheumatoid arthritis.     

On-admission anemia predicts mortality in COVID-19 patients: A single center,retrospective cohort study

ObjectivesWe investigated the impact of anemia based on admission hemoglobin (Hb) level as a prognostic risk factor for severe outcomes in hospitalized patients with coronavirus disease 2019 (COVID-19).MethodsA single-center, retrospective cohort study was conducted from a random sample of 733 adult patients (age ≥ 18 years) obtained from a total of 4356 laboratory confirmed SARS-CoV-2 cases who presented to the Emergency Department of Montefiore Medical Center between March–June 2020. The primary outcome was a composite endpoint of in-hospital severe outcomes of COVID-19. A secondary outcome was in-hospital all-cause mortality.ResultsAmong the 733 patients included in our final analysis, 438 patients (59.8%) presented with anemia. 105 patients (14.3%) had mild, and 333 patients (45.5%) had moderate-severe anemia. Overall, 437 patients (59.6%) had a composite endpoint of severe outcomes. On-admission anemia was an independent risk factor for all-cause mortality, (Odds Ratio 1.52, 95% CI [1.01–2.30], p = 0.046) but not for composite severe outcomes. However, moderate-severe anemia (Hb < 11 g/dL) on admission was independently associated with both severe outcomes (OR1.53, 95% CI [1.05–2.23], p = 0.028) and mortality (OR 1.67, 95% CI [1.09–2.56], p = 0.019) during hospitalization.ConclusionAnemia on admission was independently associated with increased odds of all-cause mortality in patients hospitalized with COVID-19. Furthermore, moderate-severe anemia (Hb <11 g/dL) was an independent risk factor for severe COVID-19 outcomes. Moving forward, COVID-19 patient management and risk stratification may benefit from addressing anemia on admission.