Dr K. N. Agarwal, Professor Pediatrics
University College Medical Sciences & GTBH, Delhi-110095.
Email: kna_noida@hotmail.com

Iron deficiency in infancy and childhood : (3,4)
Iron deficiency without anemia (impaired hemoglobin production), includes children whose hemoglobin has fallen but not below the cut off to meet the definition of anemia: Their growth, physical activity and mental functions could be affected. On administration of iron rise in hemoglobin, confirms the diagnosis of iron deficiency (Responders). Further, in childhood to meet the needs of growth iron stores may be low or absent (Low/ no bone marrow iron), with reduced serum Ferritin (But not below the cut off level of < 10 ug/l). These were not iron deficient but vulnerable to develop. Once anemia sets in clinical manifestations appear as described below.

The prevalence of iron deficiency anemia is around 50-70% in rural as well as urban studies. In an ICDS block of northeast Delhi in the proximity of a medical school operative since 1979, in 523 children of 9-36 months of age, found 63.5% with <11.0g/dl of hemoglobin (7.8% had hemoglobin < 7.0g/dl) and 87.1% had serum ferritin < 10ug/l. This shows apathy in recognizing and controlling the most common nutritional anemia which is manageable.

Clinical manifestations in iron deficiency (anemia) : (1, 2)

• Impairs growth in infancy
• Fatigue, irritability, palpitation, dizziness, breathlessness and headache
• Impairs muscular performance (Reduced levels of - glycerophosphate oxidase in muscle produces lactic acidosis).
• Impairs psychomotor development and cognitive functions (See above neurotransmitter alterations). Develop 'Pica' for mud, clay fibre etc.
• Poor body temperature maintenance - due to reduced conversion of thyroxine (T4) to triiodothyronine.
• Rarely increased intracranial pressure
• Epithelial changes(in order of frequency): gastritis and achlorhydria; tongue- papillary atrophy, nails - softness, flattening, koilonychias (rare below 5 years of age-iron is supplied for tissue growth by breakdown of hemoglobin) and dysphagia (common in females- Plummer-Vinson syndrome) for solid foods, with discomfort in neck near the cricoid cartilage. The condition is reversible on iron therapy before formation of web/stricture.
• Spleen is palpable in 10%
• Skeletal changes like those in chronic hemolytic anemia (33).

Iron requirements : (1,2)

In pregnancy:- the red cell mass increases by 17-25% with an overall increase in blood volume by 43% (maximum by 24 wk) and to maintain PCV levels of 40-50% as much as 450 mg of iron is needed. The additional needs were fetus 280 mg, placenta and umbilical cord 90 mg, maternal blood loss 150 mg obligatory blood loss from gut, etc - 230 mg (Total 1200 mg). It is estimated that 2/3 of the fetal iron is utilized in the formation of hemoglobin, while 1/3 is stored in the liver as ferritin to serve as iron deposit for first year of life.

In growing children: A newborn baby has 0.25 to 0.30 g of iron (80-90 mg/kg) as compared to adult male 3.5 g (50 mg/kg) and female 2.1 g (35 mg/kg). To make up this, atleast 0.8 mg must be absorbed daily for over 15 years of age. During 4-12 months of age 0.8 mg of iron daily provides 0.6 mg for growth and 0.2 mg to balance losses. Breast and cow milk contain around 1.5 mg of iron per 1000 calories (0.5-1.0 mg/l), the high bioavailability (49% absorption) from the former provides sufficient iron till the infant doubles birth weight. Iron supplementation is required in cow milk fed babies (10-12% absorption of available iron). An adult meets iron requirements by 95% recycled iron, in contrast an infant of 1 year needs 30% iron from the dietary sources as available recycled iron is 70% only. Thus, iron rich diet during weaning and in growing years of life is very important. The iron requirements at different age and stage of growth were summarized below:

Age	Iron needs in mg/kg	Start at age	Note
Birth weight gm< 1000	4	1 Month	Vitamin E deficiency
Birth weight gm1000-1500	3	1 Month	Vitamin E deficiency
Low birth weight	2	2 Months	Nil
Full term	1	4 Months	Nil
Upto 10 years	10 mg/ day
> 11 years (Girls)	15 mg/day
> 11years (Boys)	12 mg/day
Pregnant	30 mg/day

Lactation needs are met by saving of 20-25 mg of iron in amenorrhea every month. Fortunately, in India cow's milk is always boiled before feed, this removes heat labile milk component causing sub-clinical bleeding in gut. In addition, boiling in cast iron utensils provides easily absorbable dietary iron.