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Megaloblastny anemias - Practical hematology of children's age

Table of contents
Practical hematology of children's age
Embryonal hemopoiesis
Morfofunktsionalny characteristic of cells of marrow and peripheral blood
Marrow parenchyma cells
Peripheral blood of children of different age
The system of a hemostasis is normal
Etiology and pathogeny of leukoses
Acute leukoses
Acute leukoses - a preleukosis
Possibilities of a predictive assessment of a course of an acute lymphoblastoid leukosis at children
General principles of treatment of an acute leukosis
Chemotherapeutic drugs
Treatment of an acute lymphoblastoid leukosis
Treatment of myeloid forms of an acute leukosis
Infectious complications and symptomatic therapy of an acute leukosis
Consolidation and maintenance therapy of an acute leukosis
Immunotherapy
Remission and recurrence of an acute leukosis
Inborn leukosis
Neuroleukosis
Myelosis
Lymphogranulomatosis
Gematosarkoma
Macrofollicular lymphoma
Angioimmunoblastny lymphadenopathy
Leukemoid tests
Infectious lymphocytosis
Infectious mononucleosis
Leukemoid tests of different types
Dysfunctions of granulocytes
Leukopenias
Histiocytoses
Histiocytoses - an eosinophilic granuloma
Malignant histiocytosis
Family erythrophagocytal histiocytosis
Accumulation diseases
Nimann's illness — Peak
Angiopathies
Hemorrhagic vasculitis (Shenleyn's illness — Genokh)
Mayokki's purpura
Ataxy teleangiectasia
Entsefalotrigeminalny angiomatosis
Kortiko-meningealny diffusion angiomatosis
Cerebroretinal angiomatosis
Hypertrophic gemangiektaziya
Multiple and huge hemangiomas
Elastic fibrodisplaziya
Coagulopathies
Hereditary coagulopathies
Hemophilia And
Clinic of hemophilia
Treatment of hemophilia
Angiohemophilia
Cristmas disease (Kristmas's illness)
Hereditary deficit of factors of XI, XII, XIII and I
Dysfibrinogenemias
Hereditary deficit of factors of VII, X, V and II
Deficit K-vitaminozavisimykh of factors of coagulation
Syndrome of the disseminated intravascular coagulation
Clinic and diagnosis of the IDCS
Treatment of the IDCS
Thrombocytopenia
Idiopathic Werlhof's disease
Clinic and diagnosis of an idiopathic Werlhof's disease
Treatment of an idiopathic Werlhof's disease
Isoimmune Werlhof's disease
Transimmune Werlhof's disease of newborns
Trombogemolitichesky Werlhof's disease (syndrome Moshkovich)
Hereditary Werlhof's diseases
Trobotsitopatiya
Anemias
The anemias connected with blood loss
Chronic posthemorrhagic anemia
Iron deficiency anemias
Clinic and diagnosis of an iron deficiency anemia
Treatment of iron deficiency anemias
Sideroakhrestichesky, sideroblastny anemias
Megaloblastny anemias
Foliyevodefitsitny anemia
Hereditary forms of megaloblastny anemias
Hereditary dizeritropoetichesky anemias
The anemias connected with oppression of proliferation of cells of marrow
Hereditary hypoplastic anemias
Hemolitic anemias
Hemolitic anemias - an ovalocytosis, a hereditary stomatocytosis
Acanthocytosis, piknotsitoz
The hereditary hemolitic anemias connected with disturbance of activity of enzymes of erythrocytes
The hereditary hemolitic anemias connected with disturbance of structure or synthesis of hemoglobin
The acquired immune hemolitic anemias
Isoimmune hemolitic anemias
Treatment of a hemolitic illness of newborns
Autoimmune hemolitic anemias
List of references

The anemias connected with disturbance of synthesis of DNA and RNA (megaloblastny anemias)
Megaloblastny anemias integrate group of the acquired and hereditary anemias which characteristic symptom is existence of megaloblasts in marrow. In pediatric practice megaloblastny anemias meet more often than are diagnosed. At megaloblastny anemias define disturbance of synthesis of nucleic acids as a result of deficit of B12 vitamin or folic acid. The combined deficit of these factors meets seldom, only at disturbance of intestinal absorption. In other situations there is an isolated deficit or B12 vitamin, or folic acid. Despite complexity of diagnosis, these states it is necessary to try to differentiate as the differentiated approach to therapy depends on it.

B12-scarce anemia

V12yavlyaetsya vitamin the important factor participating in regulation of a haemo cytopoiesis. B12 vitamin is also called "external factor". Coming to an organism with food, he unites to "internal factor" (the glycoprotein cosecreted by covering cells of a stomach). The "external factor — an internal factor" connection is soaked up in an ileal gut. In a blood plasma B12 vitamin contacts proteins of plasma — transcobalamines. The fixed reserve assets of B12 vitamin are in a liver. And stocks are so big that can provide for several years requirements of a haemo cytopoiesis at already available exogenous deficit. B12 vitamin is a coenzyme of the fermental systems providing synthesis of pirimidinovy and purine bases and by that participates in synthesis of DNA and RNA. Deficit of B12 vitamin leads to emergence of the metabolic block at the level of 5-metilentetragidrofoliyevy acid. Synthesis of nucleic acids is broken and processes of normal proliferation of haemocytes are slowed down. And not only the erythrocytopoiesis, but also leykotsitopoez, a thrombocytopoiesis suffers.
As a result of kinetic researches of marrow the high level of an inefficient erythrocytopoiesis is found. The S-period of a cellular cycle is extended. Many cells perish, without having finished a S-phase.
There are several ways resulting in deficit of B12 vitamin and forming of a megaloblastny hemopoiesis.

  1. One of the reasons — disturbance of the general absorption, including B12 vitamin (Jones and soavt., 1987) which is observed at a number of hereditary and acquired diseases: Gee's disease, spra, terminal ileitis, diverticulums, jejunum resection, universal epitelioz. As a rule, at these states the combined deficit of B12 vitamin and folic acid is observed.
  2. The hereditary or acquired decrease in secretion of an internal factor is observed at a resection of a stomach, a mucosal atrophy.
  3. The increased consumption of B12 vitamin in a digestive tract is noted when parasitizing in guts of some types of helminths, in particular a wide tape-worm which in a large number absorbs the B12 vitamin necessary for growth of a parasite. It is interesting that in a helminth body B12 vitamin can contain in the quantities sufficient for achievement of therapeutic remission at patients.
  4. At children B12-scarce anemia can develop against autoimmune process when in blood antibodies against an internal factor appear.
  5. Hereditary deficit of the transcobalamines which are carrying out transportation of B12 vitamin to bodies and fabrics is very rare reason of megaloblastny anemia.
  6. Exogenous deficit of B12 vitamin is observed when feeding children by milk powder or use for food of the children of chest age of goat milk, in insufficient quantities containing an external factor.

The clinical picture B12-scarce of anemia is characterized by symptoms of defeat of the hemopoietic system, a digestive tract and a nervous system. It is noted astheno - a vegetative syndrome — weakness, slackness, dizziness. Skin is pale, with an icteric shade. Subikterichna scleras. Subfebrile temperature is possible. Patients can complain of pain in language, burning. At survey find a glossitis. Over time there is an atrophy of nipples, language becomes smooth, with a brilliant surface — the "varnished" language. At laboratory research find sharp decrease in gastric secretion, reduction of acidity and content of pepsin in a gastric juice. According to A. K. Kasymov and coauthors (1976), at children anemia is not an obligatory sign. Defeat of a nervous system is shown by paresthesias (feeling of crawling of goosebumps, numbness in extremities etc.). The funicular myelosis which is noted at adults at children is not described.
In peripheral blood — hyperchromic anemia, a color indicator 1,2 — 1,4. Anemia of normokhromny character is also possible. In smears define a macrocytosis of erythrocytes, sometimes find dipsotherapies. In erythrocytes it is possible to see Joly's little bodies — the remains of nuclear chromatin, Cabot's ring — the remains of the nuclear envelope having a ringlet appearance, and Veydenreykh's motes — the remains of nuclear substance. The number of reticulocytes is lowered. Along with anemia are possible moderate leucio-and thrombocytopenia. The Megaloblastny type of a hemopoiesis is established only at research of marrow. Megaloblasts represent cells of the big sizes of which existence of a young kernel with a gentle net of chromatin and rather mature gemoglobinizirovanny cytoplasm is characteristic. That is there is a dissociation between degree of a maturity of a kernel and cytoplasm. Along with megaloblasts in marrow define huge forms of granulocytes and megacaryocytes. In a miyelogramma — the expressed hyperplasia of an erythroidal sprout, a leykotsitarnoeritrotsitarny ratio it is equal to 1:1; 1:2.
At B12-scarce anemia there is a moderate intra marrowy hemolysis of erythroidal cells that leads to increase of level of an indirect bilirubin.
For confirmation of the diagnosis determine the content of B12 vitamin in blood serum.
Treatment of B12-scarce of anemia should be begun with elimination of the reason: carrying out deworming, treatment of gastrointestinal diseases, purposes of a balanced diet etc. Pathogenetic therapy consists in purpose of drugs of B12 vitamin. The best effect is observed at intramuscular use of drugs. Cyanocobalamine enter in a daily dose 5 mkg/kg of weight to babies, 100 — 200 mkg — to children are more senior than year and 200 — 400 mkg — at youthful age. The course of treatment is continued by 3 — 4 weeks. Already by the end of the first week positive hematologic dynamics in the form of increase in peripheral blood of quantity of reticulocytes — reticulocytic crisis is noted. Criteria of kliniko-hematologic remission: normalization of composition of peripheral blood, a marrowy hemopoiesis, normal level of B12 vitamin in blood serum, lack of clinical signs of a disease. If the cause of B12-scarce of anemia is removed, then there is no need for further therapy. In other situations the maintenance therapy in the form of annual preventive courses is recommended.
If there is an isolated deficit of B12 vitamin, then administration of folic acid is inexpedient. At B12-foliyevodefitsitnoy hemotransfusion anemias, appoint according to vital indications (a heavy anemic hypoxia, an anemic prekoma or a coma). It is desirable to use a packed red cells or the washed erythrocytes.



 
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