Safety of Ferric Carboxymaltose in Children: Report of a Case Series from Greece and Review of the Literature

Parenteral iron therapy in children with iron deficiency anemia

Iron deficiency anemia (IDA) continues to be a global public health problem. Oral iron is the universally accepted first-line therapy, and most children have a prompt and favorable response to oral formulations. In subsets of children who fail to respond due to intolerance, poor adherence, or inadequate intestinal absorption, parenteral iron is indicated. Despite numerous studies in adults with IDA of diverse etiologies, pediatric studies on parenteral iron use are very limited. Although mostly retrospective and small, these studies have documented the efficacy and safety profile of intravenous iron formulations. In this editorial the author comments on the most important published data and underscores the need to seriously consider parenteral iron use in children unresponsive to oral therapy.

Management of Childhood Iron Deficiency Anemia in a Developed Country-A Multi-Center Experience from Croatia

Iron deficiency anemia (IDA) continues to be a global public health concern, mostly in the developing countries. However, precise epidemiological data on childhood IDA in Croatia are lacking. In order to establish its frequency, underlying etiologies, the rationale for tertiary care visits, diagnostic practices, and current treatment regimens of IDA, medical records of children referred to pediatric hematologists for iron deficiency in a five-year period at tertiary institutions (Zagreb, Rijeka, Split, Osijek) throughout Croatia were retrospectively analyzed. Eight hundred and sixty-four children, predominately of preschool age, were referred mainly by the primary care pediatricians, who, in general, performed basic diagnostics but failed to initiate oral iron therapy in half of the patients. Approximately one-third of patients were symptomatic, with inadequate nutrition prevailing as underlying etiology. Dextriferron was the preferred iron formulation among hematologists, with a median dose of 5 mg/kg, with acceptable compliance rates (63.5-93.2%). Hospital admission rates varied among the centers (9.4-35%), and so did transfusion policies (6.4-22.9%). The greatest difference was observed in the frequency of parenteral iron administration (0.3-21.5%). In conclusion, the burden of childhood IDA, even in a high-income country, remains substantial, necessitating consistent implementation of national guidelines and additional education of primary health care providers.

Intravenous Iron Therapy for Children With Iron Deficiency Anemia

Iron deficiency anemia in children is a public health problem. Although oral iron treatment is the first choice, common side effects and compliance problems can cause the treatment to be interrupted. This study retrospectively evaluated children treated with intravenous (IV) iron sucrose or ferric carboxymaltose (FCM) and compared the treatment processes and efficacy. The demographic characteristics and treatment details of the 44 children with iron deficiency anemia were retrospectively evaluated. Iron sucrose was administered to 25 patients and FCM was administered to 19 patients. The IV iron infusion was applied to 64% of the patients because of unresponsiveness to oral treatment, 25% of the patients because of compliance problems, and 11% of the patients because of severe anemia. IV iron therapy increased hemoglobin, mean corpuscular volume, mean corpuscular hemoglobin, red-cell distribution width, and serum ferritin levels and decreased platelet count. The mean number of infusions per patient in the FCM group was lower, and the total treatment time was shorter. In conclusion, IV iron sucrose or FCM can be used in children with nonadherence to oral therapy and severe anemia in addition to specific indications.

High-Dose Intravenous Iron with Either Ferric Carboxymaltose or Ferric Derisomaltose: A Benefit-Risk Assessment

The intravenous iron formulations ferric carboxymaltose (FCM) and ferric derisomaltose (FDI) offer the possibility of administering a large amount of iron in one infusion. This results in faster correction of anemia and the formulations being better tolerated than oral iron formulations. This triad of logistic advantages, improved patient convenience, and fast correction of anemia explains the fact that intravenous iron formulations nowadays are frequently prescribed worldwide in the treatment of iron deficiency anemia. However, these formulations may result in hypophosphatemia by inducing a strong increase in active fibroblast growth factor-23 (FGF-23), a hormone that stimulates renal phosphate excretion. This effect is much more pronounced with FCM than with FDI, and therefore the risk of developing hypophosphatemia is remarkably higher with FCM than with FDI. Repeated use of FCM may result in severe osteomalacia, which is characterized by bone pain, Looser zones (pseudofractures), and low-trauma fractures. Intravenous iron preparations are also associated with other adverse effects, of which hypersensitivity reactions are the most important and are usually the result of a non-allergic complement activation on nanoparticles of free labile iron-Complement Activation-Related Pseudo-Allergy (CARPA). The risk on these hypersensitivity reactions can be reduced by choosing a slow infusion rate. Severe hypersensitivity reactions were reported in < 1% of prospective trials and the incidence seems comparable between the two formulations. A practical guideline has been developed based on baseline serum phosphate concentrations and predisposing risk factors, derived from published cases and risk factor analyses from trials, in order to establish the safe use of these formulations.

Hypersensitivity to Intravenous Iron Preparations

Intravenous iron is widely used for the treatment of iron deficiency anemia when adherence to oral iron replacement is poor. Acute hypersensitivity reactions during iron infusions are very rare but can be life threatening. Major risk factors for hypersensitivity reactions include a previous reaction to an iron infusion, a fast iron infusion rate, multiple drug allergies, atopic diseases, high serum tryptase levels, asthma, and urticaria. The management of iron infusions requires meticulous observation, and, in the event of an adverse reaction, prompt recognition and severity-related interventions by well-trained medical and nursing staff. Avoidance of IV iron products in patients with iron hypersensitivity reactions may not be considered as a standard practice.