Diagnosis of sideroblastic anemia

In hereditary forms in the hemogram, anemia of varying severity is revealed. As a rule, with age, anemia increases, has a hypochromic character (the color index is reduced to 0.4-0.6). In the smears, hypochromic erythrocytes are found, along with that, there are also normochromic ones among them; also determine anisocytosis with a tendency to microcytosis, poikilocytosis. The number of reticulocytes within the normal range. The number of leukocytes and platelets is within the normal range.

When lead intoxication in the hemogram reveals hypochromic anemia, hypochromic erythrocytes, target forms, anisocytosis with a tendency to microcytosis. The constant characteristic symptom of lead intoxication is the basophilic granularity of erythrocytes.

In the bone marrow there is hyperplasia of the erythroid sprout, the ratio of different forms of normocytes varies: the number of basophilic cells increases and the number of hemoglobinized oxyphilic normocytes decreases sharply. Pathognomonic is the increase (d 70% in hereditary forms) of the number of sideroblasts (identified with a special color), having a characteristic morphology. The iron granules in the cell encircle the nucleus-ring-shaped sideroblasts. This morphology is due to the accumulation of iron, not used for the synthesis of heme in the mitochondria of the cell.

At a biochemical research at all forms the increase of serum iron level in 2-4 times and more in comparison with norm is marked. The saturation ratio of transferrin by iron increases to 100 %.

Diagnosis of sideroblastic anemia

The diagnosis of hereditary forms of anemia is confirmed by the study of the content of porphyrins in erythrocytes. It was established that the hereditary forms of sidero-achestic anemia decreased the content of protoporphyrin of erythrocytes. The content of coproporphyrin erythrocytes is both elevated and low. Normally, the average level of protoporphyrin of erythrocytes in whole blood is 18 μg%, and the upper limit in the absence of anemia is 35 μg%. To study the content of iron stores and confirm hemosiderosis, a desferase test is used. After intramuscular injection of 500 mg of desferal, normally 0.6-1.2 mg of iron per day is excreted in the urine, and in patients with sideroblastic anemia 5-10 mg / day.

To diagnose lead poisoning, the level of lead in venous blood is determined; the level of protoporphyrin on erythrocytes in whole blood - a level above 100 μg%, usually indicates a toxic effect of lead.

In chronic lead poisoning on the radiographs of the knee joints, expansion and compaction of calcification sites in the distal sections of the femur, proximal sections of the tibia and fibula bones (lead lines) are observed. In case of acute poisoning due to swallowing of objects containing lead, they can be detected by means of an overview radiograph of the abdominal cavity in the anteroposterior projection. The x-ray of the knee joints in children under 3 years of age is difficult to interpret, as for the lead lines, normal bone changes can be made during a period of rapid growth. The characteristic localization of bone changes is highly likely to indicate chronic lead intoxication. Lead lines, as a rule, appear when the level of lead is longer - more than 6 weeks - exceeds 50 μg %.

With a moderate increase in lead levels in the blood (35-45 μg%), if the results of other studies are contradictory, a sample with EDTA is performed. Calcium disodium EDTA is administered at a dose of 1000 mg / m ² / day or 35 mg / kg / day intramuscularly or as an intravenous infusion for 1 hour. The test is considered positive if urine collected during the day contains 1 μg of lead per 1 mg of the administered EDTA dose. There is no sense in determining the concentration of lead in the urine. The diagnostic value is only the amount of lead excreted for a certain period of time, based on the administered dose of EDTA. When carrying out the test, it is necessary to ensure the intake of a sufficient amount of liquid and collect all the urine. In the general analysis of urine in lead intoxication, leukocyturia, cylindruria, glucosuria or aminoaciduria can be detected (usually when the concentration of lead in the blood exceeds 100 μg%).

Patient examination plan for sidero-achestic anemia

1. Analyzes confirming the presence of sidero-achestic anemia.
   • Clinical analysis of blood with determination of the number of reticulocytes and morphological characteristics of erythrocytes.
   • Myelogram with obligatory staining of smears on Berlin azure to reveal ring-shaped sideroblasts.
   • Biochemical blood test: "iron-complex", ALT, ACT, FMFA, bilirubin, sugar, urea, creatinine.
2. Analyzes that specify the form of sidero-achestic anemia.
   • The level of protoporphyrin erythrocytes in whole blood.
   • The level of lead in whole blood.
   • Desferal test.
   • Sample with EDTA.
   • Roentgenogram of knee joints.
3. Anamnesis of a child's life. Pay special attention to the place of residence, home conditions, the environment, the features of appetite, nutrition, behavior, the frequency of the chair. Clarify what medicines the child takes.
4. Family history - the presence of sideroblastic anemia in relatives.
5. General clinical examinations: analysis of urine, feces, ECG, examination of specialists, ultrasound of the abdominal cavity, kidney, heart and other examinations are carried out according to individual indications.

Clinical and laboratory signs of lead poisoning

	Lung	Moderate	Heavy
Source of lead	Dust or soil	Paints	Paints (eating with a perverse appetite)
Symptoms	None	Decreased appetite and behavioral disorders	Abdominal pain, irritability, drowsiness, fever, hepatosplenomegaly, ataxia, epileptic seizures, increased intracranial pressure, coma, signs of iron deficiency
Predisposing factors	Iron deficiency	Iron deficiency	Iron deficiency
Effects	Violation of cognitive abilities	Behavioral disorders, cognitive disorders	Persistent neurological disorders
Level of lead in whole blood, μg%	25-49	49-70	> 70
The level of protoporphyrin erythrocytes, μg%	35-125	125-250	> 250
Iron transferrin saturation ratio	<16	<16	<16
Serum ferritin level, ng / ml	<40	<20	<10
EDTA sample: lead content in daily urine per 1 mg of EDTA		1	> 1
Analysis of urine			Aminoaciduria, glkozuria
Radiographs of knee joints, kidneys, bladder	Without changes	Changes in knee joints	Changes in knee, kidney, bladder
Computer tomography of the head			Signs of increased intracranial pressure
Rate of excitation propagation along the nerve			Increased
General analysis and blood smear		Anemia of mild degree	Anemia, basophilic granulosis of erythrocytes

[1], [2], [3], [4], [5], [6], [7], [8],