Non-anaemic iron deficiency

Iron deficiency without anaemia is common.Patients may present with unexplained, non-specific symptoms.Iron studies will usually show a low ferritin and low transferrin saturation with a normal haemoglobin concentration.The cause of the iron deficiency should be identified and managed.There is limited evidence about the benefits of giving iron to people who do not have anaemia.If there is iron deficiency, most people can be given oral iron supplements.Iron studies are repeated after 60-90 days of oral iron supplements.Further investigations are needed if the iron deficiency has not been corrected.Some patients, including those who have not responsed to oral supplements may benefit from intravenous iron.There is no role for intramuscular injections of iron. Non-anaemic iron deficiency Presenting problemsIron is an essential element, required for several metabolic pathways and responsible for the delivery of oxygen to organs and body tissues.A deficiency can therefore result in a wide range of symptoms that are non-specific and may not be initially recognised as being due to iron deficiency.Iron deficiency without anaemia has been associated with:• weakness, fatigue, reduced exercise performance, difficulty in concentrating, and poor work productivity 5• neurocognitive dysfunction including irritability 6• fibromyalgia syndrome 7• restless legs syndrome 8• symptom persistence in patients treated for hypothyroidism 9• poor neurodevelopmental outcomes in infants born to mothers with iron deficiency.10 Diagnosing iron deficiencyIron deficiency can occur secondary to inadequate dietary intake, increased requirements (e.g.pregnancy and breastfeeding), impaired absorption (e.g.coeliac disease, bariatric surgery), or blood loss (e.g.menstrual, blood donation, gastrointestinal).A drug history should be taken particularly regarding anticoagulants, over-thecounter non-steroidal anti-inflammatory drugs and antiplatelet drugs.The underlying cause of iron deficiency should always be sought and managed.