Coombs-negative Autoimmune Hemolytic Anemia Followed by Anti-erythropoetin Receptor Antibody-associated Pure Red Cell Aplasia: A Case Report and Review of Literature

Immune checkpoint inhibitor-induced pure red cell aplasia: Case series and large-scale pharmacovigilance analysis

INTRODUCTION

Impressive advances in immunotherapy, especially immune checkpoint inhibitors (ICIs), have made great progress in treating multiple cancers. However, ICIs can also cause serious, even incurable, immune-related adverse events (irAEs), most often in patients with colitis, dermatitis, hepatitis, and thyroiditis. Rare autoimmune hematologic toxicities have been reported in the literature but are poorly described. Pure red cell aplasia (PRCA) induced by ICIs is a life-threatening autoimmune disease; however, only a few cases have been reported in the literature.

OBJECTIVE

To characterize and evaluate PRCA associated with different ICI regimens in a public database and to review the relevant literature.

METHODS

We described a case series of patients experiencing PRCA while on ICIs. We also mined the Food and Drug Administration's Adverse Event Reporting System (FAERS) and used reporting odds ratio (ROR), proportional reporting ratio (PRR), Bayesian confidence propagation neural network (BCPNN), and multi-item gamma Poisson shrinker (MGPS) algorithms to analyze the data of the suspected adverse events of PRCA induced by ICIs between January 2011 and June 2022.

RESULTS

Fifteen patients with PRCA events while on ICIs were included in our case series. In FAERS, a total of 41 individual case safety reports (ICSRs) with different ICI regimens were retrieved, among which 28 (68.3%) were related to monotherapy and three (7.3%) involved a fatal outcome. Signals of PRCA for all four ICI monotherapies (nivolumab, pembrolizumab, durvalumab, and atezolizumab) and ICI combination therapy (ipilimumab/nivolumab) were detected. Ipilimumab/nivolumab presented a higher reporting signal than nivolumab.

CONCLUSIONS

There is a significant reporting signal of PRCA with several ICI agents. Clinicians should be aware of and monitor this potentially fatal adverse event.

A case of pure red cell aplasia during nivolumab therapy for cardiac metastatic melanoma

Nivolumab is an antibody against programmed cell death 1 and functions as an immune checkpoint inhibitor for various malignancies, including unresectable melanomas. Nivolumab causes several immune-related adverse events, which typically include skin rash, pneumonitis, thyroid dysfunction, hepatitis, and colitis; in rare cases, anemia may be present. There are several reports of autoimmune hemolytic anemia that has developed in response to nivolumab; however, there are few reports of pure red cell aplasia (PRCA). We describe a patient who developed PRCA during nivolumab administration. A 70-year-old Japanese woman received nivolumab for cardiac metastasis from malignant melanoma from an unknown site. Twenty-one months after nivolumab administration (31 courses), treatment was discontinued because she developed severe anemia. Blood test results indicated normocytic, normochromic anemia, and reticulocytopenia, but all other components were normal. Bone marrow aspiration showed increased megakaryocytes and decreased erythroblasts; these findings were consistent with PRCA. Anemia improved without recurrence after treatment with corticosteroids and blood transfusions. The steroid dosage was reduced gradually, and to date, the patient has not experienced recurrence of anemia. The tumor decreased in size and the patient has shown a continued response to treatment with decrease in disease for 3 years. Although it is unclear how nivolumab causes PRCA, hematological toxicities have been reported in patients treated with immunotherapy drugs. PRCA might be an unrecognized immune-mediated adverse event that did not manifest during the clinical trial phase.

Pure red cell aplasia induced by erythropoietin

Introduction: Recombined human erythropoietin has been present in clinical practice for more than 20 years, in these therapeutic indications: anemia in kidney insufficiency, anemia during chemotherapy of tumors, prevention of anemias that appear in premature born babies, it is used for increasing autologous blood cell levels before blood transfusion, AIDS joined anemia (intensified by zidovudine), anemia joined with chronic inflammatory conditions such as rheumatoid arthritis(still in research phase). During the course of Erythropoietin treatment side effects have been noticed, that include multiple organ systems, and have different levels of frequency. Major number of studies shows connection between erythropoietin treatment and bone marrow aplasia, but small number of them states clearly defined side-effect that explains this phenomenon. Objective: Goal of this paper is to analyze available case studies of bone marrow aplasia during erythropoietin application, access their quality and causality of every study. Method: Research of literature used for the preparation of this systematic review has been conducted during the period of November-December 2017. In search for literature medical base PubMed has been used. Inclusion criteria were: available full article, publications in English language, publications conducted on humans, and case report studies. Eight studies passed selection. Results: results were presented by 5 charts: documentation size, credibility, number of case study reports of side-effects in the paper that was graded, Naranjo causality score, data extraction chart. Mean grade value of the studies quality was 7,0, while mean Naranjo score was 6,6.