74Серед всіх гормонів, що відповідають за зріст дити-ни, ключовими є гормон росту і тканинні ростові фак-тори, головним чином, інсуліноподібний фактор росту.Гормон росту -одноланцюговий поліпептид з двома поперечними дисульфідними зв'язками між цистеїнових групами, який секретується в клітинах передньої долі аденогіпофізу. Ген, відповідальний за синтез ГР (GR1), локалізований на довгому пле-чі 17-ї хромосоми (17q 22-24). Найбільш активною формою ГР є 22К-ГР з молекулярної масою 21500 дальтон, що складається з 191 амінокислоти. На частку цієї форми припадає до 95% загальної кіль-кості ГР. Форма 20К, що включає 176 амінокислот і має молекулярну масу 20 тис. дальтон, володіє зна-чно меншою активністю. Фізіологічна роль інших форм ГР незначна [1,2].Біологічні ефекти ГР досить різноманітні. У ді-тей і підлітків основним ефектом є стимуляція поздо-вжнього (лінійного) росту трубчастих і в меншій мірі губчастих кісток. Показано, що ГР здатний стимулю-вати ріст кісткової тканини без паралельної актива-ції ІФР-1 у печінці, проте не виключається і можлива роль ІФР-1, який утворюється безпосередньо в ділян-ці епіфізарної ростової пластинки (O.G.P. Isaksson, 1982). Крім того, існує гіпотеза так званого подвій-ного ефекту гормону росту (H. Green і співавт., 1985), згідно з якою ГР спочатку ініціює диференціювання різних клітин-попередників сполучної тканини, після чого ІФР-1 впливає на ріст клону цих клітин.Крім прискорення поздовжнього росту кісток, ГР бере участь в системі регуляції метаболізму кістко-вої тканини. ГР впливає на білковий, вуглеводний, жировий обміни і водно-електролітний баланс; во-лодіє анаболічною дією, посилює синтез білка, не впливаючи на протеоліз, збільшує число клітин в м'язовій тканині, сприяє затримці азоту в організмі; має виражену ліполітичну дію, підвищуючи число адипоцитів, але в той же час має ряд ефектів, спря-мованих на зменшення розмірів зрілих адипоцитів, що, в кінцевому підсумку, призводить до зниження загального обсягу жирової тканини [3,4].Генетично зумовлені форми дефіциту СТГ можна поділити на: автосомно-рецесивні, автосомно-домі-нантні та зчеплені з Х-хромосомою. До автосомно-рецесивних форм відносять -тип IA: делеція гену СТГ, тип ІБ, карликовість Коварскі та нанізм Ларо-на. Тип II -це автосомно домінантна форма дефі-циту СТГ. Х-зчеплений рецесивний тип -це тип III.Автосомно-рецесивні форми дефіциту СТГ Тип ІА. (Син.: ізольований дефіцит гормону рос-ту, примордіальний нанізм, гіпофізарний нанізм І) (ОМІМ 262400) Уперше ця форма недостатності СТГ описана Іл-лігом у 1970 році.Виникає внаслідок мутації в гені гормону росту GH1 (МІМ 139250), який розташований на 17q23.3. Делеції рамки зчитування, і нонсенс мутації призво-дять до відсутності ГР із тяжкою карликовістю; при введенні екзогенного гормону росту у пацієнтів часто утворюються антитіла до ГР [5,6].Клінічно проявляється пропорційною низько-рослістю із зниженням швидкості зросту, що є про-відною ознакою захворювання [7,8]. Затримка кіст-кового віку і відсутність кісткових дисплазій та хронічних захворювань є додатковими критеріями...
Introduction. Inborn Errors of Metabolism (IEM) are constituted a group of genetic diseases that are associated with defects in the synthesis or catabolism of complex molecules, impaired intermediary metabolism and energy production/utilization processes. The clinical manifestation of IEM is nonspecific, that looks similar to septicemia, and most often occurs in the neonatal period with life-threatening acute metabolic crises. Expanded Newborn Screening (ENS) – a biochemical study of the blood of all newborns without exception with the purpose to identify molecular markers of these diseases proved to be the most effective instrument of early IEM diagnostics. The quality of the biological samples (dried blood spots, DBS) in great extent determines the timing, accuracy, and reliability of the results of biochemical measurements. Obtaining of equivocal results in the case of analysis of poor quality DBS requires repeated laboratory tests, that delays the diagnostic process and postpones the start of specific treatment, which usually results in irreversible damage of the brain and internal organs of the child. The aim of this work is to (i) review the first results of the implementation of Expanded Newborn Screening in Ukraine (pilot part of the Baby Screen Project), and to analyze literature data regarding the negative impact of poor quality DBS on laboratory determination of IEM marker substances contents in the specimens, (ii) to characterize the typical errors in blood sampling and drying of blood spots, and (iii) to provide practical recommendations for the proper performance of these procedures. Materials and methods. Own data of retrospective analysis of the questionable ENS results was superimposed with dried blood specimens, that were investigated in the Pharmbiotest ENS Lab to outline most common inaccuracies. Based on the comparison of these data with the relevant publications it was formulated the practical recommendations for improving quality of DBS preparation to ensure the accuracy and reliability of laboratory measurements and speed up IEM diagnostics. Results. The quality of biomaterial selection is an important part of obtaining reliable results during expanded newborn screening. Capillary blood is collected in the maternity hospital from 48-72 hours (full-term) and for 7-11 days (in preterm babies) after the birth from the heel of babies. In this case, a few drops of blood are applied to a special test card made of filter paper, which is dried and sent to the laboratory. Blood tests are performed using a highly sensitive and accurate method of chemical analysis - tandem mass spectrometry in the laboratory "Pharmbiotest", located in Ukraine. Taking into analysis the low-quality samples lead to questionable results, which requires repeated DBS sampling and re-examining. This proved to be the most common cause of delaying IEM detection, diagnosis establishment, and initiation of treatment, which can be fatal for a child with severe IEM forms. Conclusions. Informing healthcare professionals and parents about the current results of laboratory monitoring of dried blood spots quality, typical errors in blood sampling and following on-site procedures and negative consequences of its improper performance, as well as providing clear practical recommendations of how these procedures should be done is a proven way of improving and speeding up IEM diagnostics.
Arnold-Chiari malformation is a defectof the cervical-medullar transition characterized bydisplacement of the cerebellar tonsils and in a numberof cases when the stem and IV ventricle extend into theforamen magnum. There are four main types of pathology,and type II is found most often.The article presents a clinical case of type II ArnoldChiari malformation in siblings. The newborn girl born afterVII pregnancy and VII physiological delivery in the termof 39-40 weeks was under observation. US examination inthe terms of 20-21 and 34 weeks of gestation diagnoseda congenital developmental defect of the central nervoussystem characterized by a “lemon”-like shape of the brain,displacement of the brain structures in the portion of theforamen magnum, ventriculomegaly, a defect of the lumbarsacral portion with formation of hernia sac, and dropsy ofamnion. The family couple refused from interruption ofpregnancy and medical-genetic examination.The basic diagnosis of the child was congenitaldevelopmental defect of the central nervous system(type II Arnold-Chiari malformation: rachischisis andhydrocephalus) including complications such as inferiortorpid paraplegia and dysfunction of the pelvic organs.Investigation of hereditary anamnesis foundcompromised heredity on the mother’s side (her mother’ssibling has Down’s syndrome), and IV child in the familyis disabled from birth due to a congenital developmentaldefect of the central nervous system – type II Arnold-Chiarimalformation.The family couple refused from a comprehensivemedical-genetic consultation during the previous andcurrent pregnancies, and magnetic-resonance imaging ofthe child.
Summary. Edwards syndrome is a hereditary disease characterized by trisomy of the 18th chromosome (trisomy 18). The occurrence of Edwards syndrome is 1 per 6 000 live births, the proportion of girls to boys is 3:1. In 95 % of all the cases of Edwards syndrome development, an extra copy of the 18th chromosome is present in the cells (complete trisomy), in 2 % the translocation of another chromosome on the 18th one is found; in 3 % of cases “mosaic trisomy” is found when the additional 47th chromosome is found not in all the cells but in a part of them. The most important, but not a single risk factor promoting the development of trisomy 18 is a woman’s age over 40. Prenatal diagnostics of Edwards syndrome includes USD and biochemical screening of a pregnant woman during the 11-13th weeks of gestation studying the levels of β-chorionic human gonadotrophine and plasma protein А, associated with pregnancy, as well as karyotype detection of the fetus in pregnant women from risk groups. The article presents a clinical case of Edwards syndrome of a newborn girl born from I pregnancy (anemia of pregnancy, early toxicosis, maternal chronic pyelonephritis, parental contact with industrial harmful factors), І physiological labour on the 40-41st week with breech presentation, body weight of 1480 g and body length of 40 cm, and 4/4 Apgar score. The woman was found to be registered regarding pregnancy since the 15th week of gestation, she positively refused screening examinations. The first USD was performed during the 30th week of gestation. It found complicated congenital developmental defects of the heart and retarded development of the fetus syndrome. The risk of a child’s birth with congenital pathology was considered to be high. The child’s condition at birth and during the whole period of treatment and care in the neonatal resuscitation unit was assessed as severe with progressive negative dynamics at the expense of deterioration of multiple organ failure signs. Examination of the patients found multiple dysmorphic signs including narrow eyelid openings, low-set ears, microstomy, micrognathia, deformities of the limbs. By means of instrumental methods of examination semilobar shape of the holoprosencephaly (Patau's syndrome), double origin of the major vessels from the right ventricle, defect of the interatrial septum, subaortal defect, right ventricular hypertrophy, defect of the intraventricular septum, the signs of pulmonary hypertension were found; cytogenetic examination detected -47, ХХ, +18, Edwards syndrome. Considering the severity of multiple developmental defects, in spite of initiated treatment, the girl died at the age of 29 days 3 hours, and 30 minutes. The underlying disease and the cause of death of a term, morphologically immature girl with a low body weight at birth was the chromosome defect – trisomy 18 (Edwards syndrome) complicated by the development of multiple organ failure. The clinical case presented illustrates an untimely diagnostics of Edwards syndrome (trisomy 18) due to late registration of the pregnant woman, her refuse from screening examinations, including USD, and detection of levels of β-chorionic human gonadotropin and plasma protein A associated with pregnancy. Late prenatal diagnostics of multiple congenital developmental defects of the fetus, lack of prenatal invasive examination with cytogenetic analysis, and diagnostics of chromosome pathology of the child after birth are associated with the solution of ethical issues concerning the choice of “aggressive” therapeutic tactics or giving palliative aid to the child with Edwards syndrome.
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