Iron-deficiency anaemia can be caused by various factors, including:
- An iron-poor diet: A child obtains iron from food, but only a small amount is actually absorbed by the body. Full-term newborns born to healthy mothers store iron during the final three months of pregnancy. However, babies born to mothers with anaemia or other health problems may not accumulate enough iron, and premature babies have particularly low iron stores.
- Changes in the body: During periods of rapid growth, the body needs more iron to produce new red blood cells. Babies aged 4 to 6 months begin to use up the iron stores accumulated during pregnancy, so there is a risk of deficiency during this period.
- Gastrointestinal problems: Impaired iron absorption may occur after certain gastrointestinal operations or as a result of diseases that affect intestinal function. Most iron is absorbed in the upper part of the small intestine, and any disruption to this process may lead to anaemia.
The most common symptoms of anaemia in children include:
- Pale skin,
- irritability and nervousness,
- Fatigue or lack of energy,
- Increased heart rate,
- Pain or swelling of the tongue,
- An enlarged spleen,
- A desire to eat unusual substances, such as soil or ice.
The American Academy of Pediatrics (AAP) recommends screening all babies at 12 months of age for anaemia using a haemoglobin-level test. The screening should also include a risk assessment involving questions about feeding problems, faltering growth and other specific health needs. If the haemoglobin level is low, further blood tests may be performed, such as:
- Haemoglobin and haematocrit levels: This is a basic screening test that measures the amount of haemoglobin and red blood cells in the blood.
- Complete blood count (CBC): this more detailed test checks the numbers of red and white blood cells, platelets and young red blood cells (reticulocytes). A CBC also includes haemoglobin and haematocrit, as well as detailed information about red blood cells.
- Peripheral blood smear: a small blood sample is analysed under a microscope to assess the shape and appearance of blood cells.
- Iron-status tests: specific tests assess the amount of iron in a child's body.
Early detection and appropriate treatment of iron deficiency can prevent more serious health complications.
Ferritin: What Is Considered a Normal Level?
Studies conducted in paediatric sleep clinics increasingly focus on measuring serum ferritin levels in children with sleep disorders, such as restless legs syndrome (RLS), periodic limb movements during sleep (PLMD), or in children reported to have restless sleep. Ferritin, a protein that stores iron, is treated as an indicator of the body’s iron stores. However, the question remains: what ferritin level in children can be considered ‘normal’ ?
One study by Dr Rosen and colleagues analysed the effect of iron supplementation in children with RLS and ferritin levels below 50 ng/mL, which was defined as a biochemical indicator of iron deficiency. The results showed that supplementation increased ferritin levels and reduced the severity of RLS symptoms; however, no direct correlation was found between changes in ferritin levels and clinical improvement.
Ferritin Levels in Children
Studies from paediatric sleep clinics report that ferritin is routinely measured as an indicator of iron stores in children with restless legs syndrome (RLS), periodic limb movement disorder (PLMD) and restless sleep. Researchers also study children who do not meet the criteria for RLS or PLMD but have reported symptoms of restless sleep and daytime consequences. One unpublished study collected ferritin data from children who underwent sleep studies, excluding those with sleep apnoea. The source reports the following mean serum ferritin levels:
- 24.7 ng/mL (for children aged 1–5 years),
- 31.4 ng/mL (for children aged 6-11 years),
- 35.0 ng/mL (for children aged 12–19 years).
These values are very close to the ferritin levels recorded in the general population of children in the United States, suggesting that if a level below 50 ng/mL were considered iron deficiency, most children would fall into this category.
Ferritin and clinical symptoms
Although most studies suggest that children with RLS, PLMD and restless sleep may improve after iron supplementation, serum ferritin levels do not always correlate directly with symptom improvement. One possible explanation is that serum ferritin does not accurately reflect iron stores in the brain, which may play a key role in the development of these disorders. Studies of adults with RLS found significant differences in ferritin levels in cerebrospinal fluid, while serum ferritin levels remained similar in people with and without RLS.
Restful sleep can support a young child's wellbeing, which is why the source recommends our blankets and pillows Sleepee, which will provide softness and comfort every night. Another ideal solution for babies will be carrycot sheets, created with calm and safe sleep in mind from the very first moments of life.
Interpretation of ferritin levels
An important aspect of interpreting ferritin results is how they are communicated to parents. Describing ferritin levels in the range of 20-30 ng/mL as ‘low’ or indicating ‘iron deficiency’ may cause unnecessary concern about the child's health. Instead, it is suggested that such values be described as ‘suboptimal’ in the context of sleep disorders, without indicating full iron deficiency.
Emilia Adamczyk