Bruno Fattizzo

Outcomes for patients with hematologic malignancy infected with COVID-19 have not been aggregated. The objective of this study was to perform a systematic review and meta-analysis to estimate the risk of death and other important outcomes for these patients. We searched PubMed and EMBASE up to 20 August 2020 to identify reports of patients with hematologic malignancy and COVID-19. The primary outcome was a pooled mortality estimate, considering all patients and only hospitalized patients. Secondary outcomes included risk of intensive care unit admission and ventilation in hospitalized patients. Subgroup analyses included mortality stratified by age, treatment status, and malignancy subtype. Pooled prevalence, risk ratios (RRs), and 95% confidence intervals (CIs) were calculated using a random-effects model. Thirty-four adult and 5 pediatric studies (3377 patients) from Asia, Europe, and North America were included (14 of 34 adult studies included only hospitalized patients). Risk of death among adult patients was 34% (95% CI, 28-39; N = 3240) in this sample of predominantly hospitalized patients. Patients aged ≥60 years had a significantly higher risk of death than patients <60 years (RR, 1.82; 95% CI, 1.45-2.27; N = 1169). The risk of death in pediatric patients was 4% (95% CI, 1-9; N = 102). RR of death comparing patients with recent systemic anticancer therapy to no treatment was 1.17 (95% CI, 0.83-1.64; N = 736). Adult patients with hematologic malignancy and COVID-19, especially hospitalized patients, have a high risk of dying. Patients ≥60 years have significantly higher mortality; pediatric patients appear to be relatively spared. Recent cancer treatment does not appear to significantly increase the risk of death.

The clinical outcome, response to treatment, and occurrence of acute complications were retrospectively investigated in 308 primary autoimmune hemolytic anemia (AIHA) cases and correlated with serological characteristics and severity of anemia at onset. Patients had been followed up for a median of 33 months (range 12-372); 60% were warm AIHA, 27% cold hemagglutinin disease, 8% mixed, and 5% atypical (mostly direct antiglobulin test negative). The latter 2 categories more frequently showed a severe onset (hemoglobin [Hb] levels ≤6 g/dL) along with reticulocytopenia. The majority of warm AIHA patients received first-line steroid therapy only, whereas patients with mixed and atypical forms were more frequently treated with 2 or more therapy lines, including splenectomy, immunosuppressants, and rituximab. The cumulative incidence of relapse was increased in more severe cases (hazard ratio 3.08; 95% confidence interval, 1.44-6.57 for Hb ≤6 g/dL; P < .001). Thrombotic events were associated with Hb levels ≤6 g/dL at onset, intravascular hemolysis, and previous splenectomy. Predictors of a fatal outcome were severe infections, particularly in splenectomized cases, acute renal failure, Evans syndrome, and multitreatment (4 or more lines). The identification of severe and potentially fatal AIHA in a largely heterogeneous disease requires particular experienced attention by clinicians.

Several hemolytic markers are available to guide the differential diagnosis and to monitor treatment of hemolytic conditions. They include increased reticulocytes, an indicator of marrow compensatory response, elevated lactate dehydrogenase, a marker of intravascular hemolysis, reduced haptoglobin, and unconjugated hyperbilirubinemia. The direct antiglobulin test is the cornerstone of autoimmune forms, and blood smear examination is fundamental in the diagnosis of congenital membrane defects and thrombotic microangiopathies. Marked increase of lactate dehydrogenase and hemosiderinuria are typical of intravascular hemolysis, as observed in paroxysmal nocturnal hemoglobinuria, and hyperferritinemia is associated with chronic hemolysis. Prosthetic valve replacement and stenting are also associated with intravascular and chronic hemolysis. Compensatory reticulocytosis may be inadequate/absent in case of marrow involvement, iron/vitamin deficiency, infections, or autoimmune reaction against bone marrow-precursors. Reticulocytopenia occurs in 20-40% of autoimmune hemolytic anemia cases and is a poor prognostic factor. Increased reticulocytes, lactate dehydrogenase, and bilirubin, as well as reduced haptoglobin, are observed in conditions other than hemolysis that may confound the clinical picture. Hemoglobin defines the clinical severity of hemolysis, and thrombocytopenia suggests a possible thrombotic microangiopathy or Evans' syndrome. A comprehensive clinical and laboratory evaluation is advisable for a correct diagnostic and therapeutic workup of the different hemolytic conditions.

We retrospectively studied 232 patients with cold agglutinin disease (CAD) at 24 centers in 5 countries. In Norway and a northern region of Italy, the study was close to being population-based. For the first time, we demonstrate fourfold differences between cold and warmer climates regarding prevalence (20 vs 5 cases/million) and incidence (1.9 vs 0.48 cases/million per year). Mean baseline hemoglobin level was 9.3 g/dL, but 27% had hemoglobin <8 g/dL. Identification of typical features of CAD-associated lymphoproliferative disorder in the bone marrow was greatly increased by centralized biopsy assessment. CAD seems to be associated with a slightly increased risk of venous thrombosis. This work includes a follow-up study of therapies, focusing on the long-term outcomes of the rituximab plus bendamustine and rituximab plus fludarabine regimens. Rituximab plus bendamustine therapy resulted in responses in 35 (78%) of 45 patients; 24 (53%) achieved complete response. Interestingly, these rates were still higher than observed in the original (2017) prospective trial, and we also found a shift toward deeper responses with time. This is explained by the prolonged time to response seen in many patients, probably related to long-lived plasma cells. In patients responding to rituximab-bendamustine, median response duration was not reached after 88 months, and estimated 5-year sustained remission was 77%. The regimen appeared safe regarding late-occurring malignancies. Rituximab plus fludarabine therapy seems to carry a higher risk of long-term adverse effects.

This prospective study investigated the efficacy, safety, and response duration of low-dose rituximab (100 mg fixed dose for 4 weekly infusions) together with a short course of steroids as first- or second-line therapy in 23 patients with primary autoimmune hemolytic anemia (AIHA). The overall response was 82.6% at month +2, and subsequently stabilized to ∼ 90% at months +6 and +12; the response was better in warm autoimmune hemolytic anemia (WAIHA; overall response, 100% at all time points) than in cold hemagglutinin disease (CHD; average, 60%); the relapse-free survival was 100% for WAIHA at +6 and +12 months versus 89% and 59% in CHD, respectively, and the estimated relapse-free survival at 2 years was 81% and 40% for the warm and cold forms, respectively. The risk of relapse was higher in CHD and in patients with a longer interval between diagnosis and enrollment. Steroid administration was reduced both as cumulative dose (∼ 50%) and duration compared with the patient's past history. Treatment was well tolerated and no adverse events or infections were recorded; retreatment was also effective. The clinical response was correlated with amelioration biologic markers such as cytokine production (IFN-γ, IL-12, TNF-α, and IL-17), suggesting that low-dose rituximab exerts an immunomodulating activity. This study is registered at www.clinicaltrials.gov as NCT01345708.