Background. The study of anemia causes in children born prematurely remains the urgent problem due to the continuous search for effective ways to prevent and treat it.

Objective. The aim of the study is to study the anemia severity in premature infants, peripheral blood test results (MCV, MCH, MCHС), serum iron, and ferritin at different gestational periods.

Materials and methods. 82 medical records of preterm infants were analyzed. 12 children were extremely premature (EР), 36 were very premature (VP), 27 were moderately premature (MP), and 7 were late premature (LP). The frequency of anemia, its severity, and laboratory indicators of iron metabolism were studied.

Results. In EР infants, anemia developed in 100% (severe and moderate form in 16.7%, mild in 66.6%), in VP — in 94.6% (of which severe form in 5.6%, moderate — 22%, mild — 67%). Severe forms were not detected in children over 32 weeks of gestation. In infants with ЕР, the iron level at 2 weeks Me (median) 10.6 μmol/l [8.8–12.1], which is lower than in the comparison groups: VP — 15.9 [12.3–18.9] (p = 0.007), MP — 18,7 [15.8–20.5] (p = 0.0002), LP — 14,0 [16.2–23.8] (p = 0.011). Serum ferritin in the EР group is 58.4 μg/l [52.8–71.7], lower than the level in children with OH — 165.5 μg/l [77.3–195] (p = 0.03). The indicators MCV, MCH did not reflect the etiology of anemia, MCHC is reduced in all groups. With oral subsidization of 3-valent iron, its level increase in EР: before treatment — 10.65 μmol/l [8.2–12.1], after 2 weeks — 21.95 μmol/l [17.8–23,9] (p = 0.011).

Conclusion. Severe and moderate degrees of early anemia of prematurity are diagnosed in the EР and VP groups. Significant deficiency of serum iron was detected in EР at the age of 2 weeks. MCHC less than 33.1% was registered in all gestational periods, it can be the marker of early anemia of prematurity. Iron supplement is required for EР.

Background. Anemia affects one third of the world's population. Many scientific publications are devoted to anemia. Side issues of morbidity and prevalence of rare forms of anemia (RFA) and severe iron deficiency anemia (IDA) in children are not sufficiently covered due to difficulties with its assessment.

Objective. The aim of the study is to study incidence and prevalence of severe IDA and RFA among children of Orel.

Materials and methods. Cohort epidemiological study of primary blood system diseases in children aged from 5 days to 18 years was conducted based on the only children's department of hematology in Orel region. Inclusion of new patients and event fixation (recovery, death, relapse, loss for observation) were performed prospectively. According to the obtained data, incidence and prevalence rates were calculated. Follow-up duration was 1–5 years.

Results. 175 novel cases of blood diseases were recorded over 5 years. 160 were subject for analysis, including 28 cases of severe IDA and 27 cases of RFA. The mean incidence rate of severe IDA was almost equal to its prevalence and was 4.1 (standard deviation (SD) = 1.5), RFA — 4.0 (SD = 2.1) per 100,000 of children population. Mean incidence rate of hereditary spherocytosis was 1.48 (SD = 2.1), megaloblastic anemia (V12-DA) — 0.74 (SD = 0.90) acquired aplastic anemia (AA) — 0.59 (SD = 0.81), beta-thalassemia — 0.45 (SD = 0.66), autoimmune hemolytic anemia (AIHA) — 0.44 (SD = 0.66), congenital АА — 0.30 (SD = 066) per 100,000 of children population.

Conclusion. The incidence and prevalence of severe IDA and RFA among children of Orel region is comparable to the world literature data. The incidence rate of children with megaloblastic anemia was calculated for the first time.