Microcephaly, an etiopathogenic vision

Microcephaly is defined by an occipital-frontal head circumference (OFD) 2 standard deviations (SD) smaller than the average expected for age, gender and population. Its incidence has been reported between 1.3 150 cases per 100,000 births. Currently, new clinical characteristics, causes pathophysiological mechanisms related to microcephaly continue be identified. etiology varied heterogeneous, with genetic non-genetic factors that produce alterations in differentiation, proliferation, migration, repair of damage deoxyribonucleic acid neuronal apoptosis. It requires a multidisciplinary diagnostic approach includes medical history, detailed prenatal postnatal evaluation, cerebral magnetic resonance imaging, neuropsychological some complementary tests such as metabolic screening, rule out infectious processes testing. 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XI (Available https://www.yumpu.com/en/document/read/53708588/alteraciones-del-perimetro-craneal-microcefalia-y-macrocefalia): 701-716Google Both types acquired.4Passemard Primary (PM) tends static result loss balance proliferation progenitor cells death.4Passemard Most PM disability varying degrees, progressive, without neurological, alterations.1Mochida Scholar,3Mahmood Scholar,4Passemard Scholar,40Roberts E. Hampshire D.J. Pattison Springell Jafri Corry al.Autosomal analysis locus phenotypic variation.J 39: 718-721Crossref (102) secondary (SM), birth, decreases postnatally evident first year life. often involves neurodegeneration and/or cells.4Passemard SM, progressive cognitive impairment present seizures.41Woods Human microcephaly.Curr 112-117Crossref (146) all cases, weight height should evaluated, since these 3rd percentile proportionate/symmetric if only altered disproportionate/asymmetric microcephaly.6Harris important evaluate whether extracranial (complex/syndromic isolated) present1Mochida integrate known syndromic diagnosis.42Stevenson R.E. Hall J.G. malformations anomalies. York2006Google also intrinsic (in genetic) extrinsic/environmental wide variety degeneration previously (Figure 1).42Stevenson listed below:a)Microcephaly hereditary Non-syndromic vera rare, genetically heterogeneous disorder.4Passemard According Online Mendelian Inheritance Man (OMIM) database,43OMIMOnline Man. online catalog genes disorders.https://www.omim.orgGoogle far 25 (MCPH) identified, respective involved.b)Microcephaly impaired migration occur neurons do migrate correct position within central system.41Woods Multiple which, presenting mutations, lissencephaly, pachygyria heterotopia bands (Table A, supplementary information).c)Microcephaly deficiency ventricular subventricular areas system. cross-links, strand breakage, base distortion helices stem progenitors, different biochemical pathways lesions prevent spread damage.44McKinnon P.J. Caldecott K.W. break disease.Annu 8: 37-55Crossref (201) Scholar,45McKinnon disease.Nat 100-112Crossref Defects neuropathological type moment they occur, being commonly observed characteristics patients defects single rupture, double caused nucleotide cleavage B, information).4Passemard Scholard)Microcephaly Several inborn errors metabolism microcephaly; actual prevalence children anomaly unknown (some studies delay estimated 1–5%).5von enzymes carbohydrates, proteins lipids accumulation toxic metabolites essential intrauterine C, information).e)Acquired congenital Acquired occurs after exposure extrinsic (ischemic processes, radiation substances maternal disease) pregnancy affect 1). Prenatal susceptibility composition, genetic-environmental interaction, intensity duration exposure.46Brassier Ottolenghi Boddaert Sonigo Attié-Bitach T. Millischer-Bellaiche A.E. al.Prenatal symptoms inherited diseases.Arch Pediatr. 19 ([Article French]): 959-969Crossref (14) However, possible determine exact amount each agent required induce brain. Thus, more vulnerable effects two trimesters pregnancy, differentiation greater, process organization synaptogenesis.4Passemard Scholar,47Graf W.D. Kekatpure M.V. Kosofsky B.E. Prenatal-onset toxins, nutritional deficiencies, illness.Handb 143-159Crossref (10) ScholarTable 1Common ScholarPrenatal infections systemAgent, factor diseaseBrain abnormalitiesPresence calcificationsOther anomaliesCytomegalovirusVentriculomegaly, subependymal cysts disordersYesChorioretinitis, hearing loss, hyperechogenic bowel, restriction (IUGR) oligohydramniosHerpes simplex virusHydrocephalus, porencephalic cyst cystsYesChorioretinitis microphthalmiaRubellaSubependymal cystsYesHearing cataracts, retinopathy, cardiac abnormalities IUGRToxoplasmosisHydrocephalus (aqueductal stenosis)YesChorioretinitis optic atrophySyphilisHydrocephalus pseudoparalysisYesHearing dental anomalies pulmonary hemorrhageVaricella zosterHydrocephalus atrophyNoMicrophthalmia, chorioretinitis, skeletal abnormalities, limb hypoplasia, IUGR scarsAcquired immunodeficiency syndromeCerebral atrophy, ventriculomegaly white matter abnormalitiesYesLong palpebral fissures, hypertelorism, blue sclera, depressed nasal bridge, deep philtrum, prominent vermilion border IUGRZika virusCortical ventriculomegaly, corpus callosum enlargement subarachnoid space, cerebellar mega cisterna magna delayed myelinationYesHypertonia/spasticity, hyperreflexia, epileptogenic activity, arthrogryposis, visual disturbancesPrenatal drugs substancesAlcoholAgenesis abnormal gyrationNoDysmorphic facial features, renal anomalies, scoliosis IUGRCocaineIntracranial hemorrhage encephaloceleNoCraniofacial abnormalitiesAnti-epileptic (carbamazepine, phenytoin, barbiturates sodium valproate)Spina bifidaNoDysmorphic cleft, digital IUGRMaternal diseases factorsPhenylketonuriaAbnormal gyrationNoSmall gestational dysmorphic esophageal atresia, vertebral defects, bladder exstrophy, IUGRPlacental insufficiency, malnutrition, anemia systemic diseaseImpaired axonal cytoarchitecture, neurodegeneration, porencephaly, periventricular leukomalacia tube defectsNoAcute encephalopathy, hypotonia, microphthalmia, sensorineural anemia, IUGRHypoxic-ischemic (pre postnatal)/Intraventricular hemorrhageBasal ganglia, thalamus, cortex hypoplasia callosum, dilatation diffuse gray abnormalitiesYesEpileptogenic hypotonia hypertonia, hemiplegia, diplegia quadriplegia, behavioral Open table tab During ultrasonographic skull end second third trimester.3Mahmood proper directly estimation age calculation OFC. Alternatively, calculated biparietal diameter (BPD) = 1.62 × (BPD + OFD).3Mahmood acceptable plane measurement OFC, BPD OFD cross-sectional view level thalami where symmetrical appearance both hemispheres broken midline echo continuity cavum septum pellucidum (“box-like” CSP) “V-shaped” ambient cistern (AC), show entire cerebellum (CBL). To measure calipers placed outer edge superior inferior parietal bones through widest part OFD, edges point midline.48Loughna Chitty Evans Chudleigh Fetal dating: charts recommended obstetric practice.Ultrasound. 17: 160-166Crossref (130) Scholar,49Kim H.P. Lee S.M. Kwon J.Y. Park Y. Kim K.C. Seo Automatic biometry ultrasound images using machine learning.Physiol Meas. 2019; 40065009Crossref (24) calculating boundary ellipse drawn around outside calvarium 2). recorded plotted international curve INTERGROWTH-21 calculate age.50The global health networkINTERGROWTH-21st.https://intergrowth21.tghn.orgGoogle As performed placing non-elastic measuring tape cm above eyebrows (glabella), occiput ears (without touching them). Since thickness cephalic soft tissues (edema, cephalohematoma, caput succedaneum) modify it, confirmed 24 h birth.6Harris sex group patient having curves standardized World Health Organization), later SD. A (maternal–fetal medicine physician, pediatrician, neurologist geneticist) history included, family least three previous generations. structural examination performed, birth.4Passemard Cerebral imaging suggested sensitive method identify microcephaly.5von perform 90% except origin, find persons intelligence.3Mahmood performance indicated those demonstrated: electroencephalogram, ophthalmological echocardiogram, auditory toxoplasmosis others -syphilis, chickenpox parvovirus-, rubella, cytomegalovirus herpes (TORCH), conventional cytogenetic G bands, fluorescence situ hybridization (FISH), comparative genomic microarray-hybridization (CGH), microarray-polymorphism (SNP) exome sequencing.4Passemard Regardless surveillance curve. periodic evaluations order monitor development. prevented, example, surgery release sutures younger 1 age.6Harris All referred service confirm purpose support members, help understand natural disease, and, available. critical explain risk recurrence contributes disease course, taking educational cultural parents. values, beliefs, goals relationships affected relative members services, psychology appropriate.51López-Muñoz Becerra-Solano L.E. amniotic sequence.Arch Argent 2018; 116 English, Spanish]): e409-e420PubMed make since, even prevented appropriate patients. Finally, identification makes establish comprehensive plan families.