Clinical features and genetic analysis of a child with acute form of Tyrosinemia type I due to a novel variant of FAH gene / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical phenotype and genetic basis for a child with acute form of tyrosinemia type I (TYRSN1).@*METHODS@#A child with TYRSN1 who presented at the Gansu Provincial Maternal and Child Health Care Hospital in October 2020 was selected as the subject. The child was subjected to tandem mass spectrometry (MS-MS) and urine gas chromatography-mass spectrometry (GC-MS) for the detection of inherited metabolic disorders, in addition with whole exome sequencing (WES). Candidate variants were validated by Sanger sequencing.@*RESULTS@#The child's clinical features included abdominal distension, hepatomegaly, anemia and tendency of bleeding. By mass spectrometry analysis, her serum and urine tyrosine and succinylacetone levels have both exceeded the normal ranges. WES and Sanger sequencing revealed that she has harbored c.1062+5G>A and c.943T>C (p.Cys315Arg) compound heterozygous variants of the FAH gene, which were inherited from her father and mother, respectively. Among these, the c.943T>C was unreported previously.@*CONCLUSION@#Considering her clinical phenotype and result of genetic testing, the child was diagnosed with TYRSN1 (acute type). The compound heterozygous variants of the FAH gene probably underlay the disease in this child. Above finding has further expanded the spectrum of FAH gene variants, and provided a basis for accurate treatment, genetic counseling and prenatal diagnosis for her family.

Tyrosinemia type iii: a case report of siblings and literature review / Tirosinemia tipo iii: descrição de caso clínico em irmãos e revisão da literatura

ABSTRACT Objective: Tyrosinemia type III (HT III) is the rarest form of tyrosinemia, and the full clinical spectrum of this disorder is still unknown. The neurological involvement varies, including intellectual impairment and attention deficit disorder with hyperactivity (ADHD). We report the case of two siblings diagnosed with HT III at different ages. Case description: The index case was diagnosed by newborn screening for endocrine and metabolic disorders, starting a low-protein diet immediately, with a consistent decrease in tyrosine levels. By the age of three, the child displayed a hyperactive behavior, starting treatment for ADHD two years later. At seven years of age, he shows a slight improvement in terms of behavior and attention span and has a cognitive performance slightly lower than his peers, despite maintaining acceptable tyrosine levels. His sister, who had a history of ADHD since age five, was diagnosed with HT III after family screening at the age of eight. Despite initiating a dietetic treatment, her behavior did not improve, and she has a mild intellectual impairment. Comments: This is the first case report describing siblings with HT III who underwent nutritional treatment with a low-protein diet in different phases of life, with a better neurological and behavioral evaluation in the patient who started treatment earlier.

RESUMO Objetivo: A tirosinemia tipo III (TT III) é a forma mais rara das tirosinemias e o espectro clínico desta entidade não está totalmente esclarecido. O envolvimento neurológico é variável, incluindo o atraso cognitivo ou transtorno do déficit de atenção com hiperatividade (TDAH). Descrevemos o caso de dois irmãos que foram diagnosticados com TT III em idades diferentes. Descrição dos casos: O caso índice foi diagnosticado no contexto do rastreio endócrino-metabólico neonatal, tendo iniciado imediatamente dieta hipoproteica, com redução consistente dos níveis de tirosina. Por volta dos três anos, foi detectado um comportamento hiperativo, tendo iniciado dois anos depois tratamento para o TDAH. Aos sete anos, apresenta leve melhora de comportamento e da atenção e avaliação cognitiva levemente inferior ou pouco abaixo quando comparado a crianças da mesma faixa etária, apesar de manter níveis aceitáveis de tirosina. A sua irmã, com história de TDAH desde os cinco anos, foi diagnosticada de TT III aos oito anos no contexto do rastreio de familiares. Apesar de iniciar tratamento dietético, nenhum efeito foi notado em termos de comportamento e a doente apresenta leve atraso cognitivo. Comentários: Este é o primeiro caso clínico descrito de irmãos com TT III que iniciaram terapêutica dietética com dieta hipoproteica em diferentes fases da vida, com melhor avaliação em termos neurológicos e comportamentais no doente que iniciou tratamento mais precocemente.

A challenging case of hereditary type 1 tyrosinaemia associated with persistent diarrhoea: Case report and literature review

Hereditary tyrosinaemia type 1 (HT1) is a rare inherited genetic disorder attributed to deficiency of the enzyme fumarylacetoacetate hydrolase (FAH). HT1 may present with diarrhoea in its acute form. We report on a 2.5-year-old Egyptian girl diagnosed with HT1. At the age of 1 year and 9 months, the patient started to have persistent diarrhoea with marked abdominal distension, anorexia and irritability, and with no fever or vomiting. At the onset of diarrhoea, liver synthetic functions deteriorated and ascites progressed, requiring frequent paracentesis. These manifestations did not improve after starting specific treatment for HT1 (2-(2-nitro-4-trifluoromethylbenzoyl)- 1,3-cyclohexanedione) (NTBC). Coeliac disease was diagnosed; this disorder was not previously reported as having an association with HT1

Screening for hereditary tyrosinemia and genotype analysis in newborns / 浙江大学学报·医学版

OBJECTIVE@#To analyze the results of screening for hereditary tyrosinemia (HT) in newborns and its clinical features and genotype.@*METHODS@#The HT screening was conducted among 2 188 784 newborns from November 2013 to November 2018. The tyrosine (TYR)/ succinylacetone (SA) levels were detected by tandem mass spectrometry (MS-MS). The clinical characteristics, genetic results and following up data of identified patients were analyzed.@*RESULTS@#The normal ranges (0.5%-95.5%) of TYR and SA were 34.5-280.0 μmol/L and 0.16-2.58 μmol/L, respectively. Three HT cases were confirmed with a detection rate of 1∶729 595. There was 1 case of tyrosinemia type Ⅰ (HTⅠ) (homozygous variations of c.455G>A in gene), 1 case of tyrosinemia type Ⅱ(HTⅡ) (heterozygous variations of c.890G>T and c.408+1G>A in gene), and 1 case of tyrosinemia type Ⅲ (HT Ⅲ) (homozygous variations of c.257T>C in gene). The variations of c.890G>T, c.4081G>A of and c.257T>C of were novel. The positive predictive value of the screening was 3.4%. Case 1 (HTⅠ) with TYR and SA values of 666.9 μmol/L and 3.87 μmol/L respectively, presented cholestasis, mild elevated of liver enzyme and lactic acid, who were although fed with TYR and phenylalanine free milk, but died at 2 months of age. Case 2 (HTⅡ) with higher TYR (625.6 μmol/L) and normal SA at screening, received medical milk treatment; during the 7 months of follow-up the baby showed normal score of Bayley assessment and normal TYR without eye and skin symptoms. Case 3 (HT Ⅲ) with TYR of 1035.3 μmol/L and normal SA at screening; during the 29 months of follow-up the value of TYR fluctuated from 532.1 μmol/L to 1060.3 μmol/L due to irregular medical milk treatment, while the score of Bayley assessment was normal.@*CONCLUSIONS@#HT is rare in the southern Chinese population, and the gene spectrum is scattered. Early treatment with nitisinone is recommended in children with HTⅠ, otherwise the prognosis is poor; the prognosis of children with HTⅡ is good when early treated with special diet; the prognosis of children with HTⅢ needs to be determined with more data.

Clinical and genetic analysis of a patient with tyrosinemia type I but without elevated succinylacetone / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical manifestation and genetic mutation of a child with tyrosinemia type I but without elevated succinylacetone.@*METHODS@#Clinical data of the patient was collected. Tandem mass spectrometry and gas chromatography mass spectrometry were used to analyze the blood amino acid and urine organic acid component of the proband. DNA was extracted from the child and his parents and used for mutation analysis.@*RESULTS@#The proband was of acute type, with features including hepatomegaly, jaundice, anemia and tendency of bleeding. Serum levels of Tyrosine, Methionine and Phenylalanine were 397.12 μmol/L, 896.16 μmol/L and 292.52 μmol/L, respectively, which all distinctly exceeded the normal levels. The level of phenyllactic acid and 4-hydroxyphenyl-lactic acid of proband's urine were 17.4 μmol/L and 417.0 μmol/L, respectively, which also exceeded the normal levels, but the level of succinylacetone was within the normal range. Compound heterozygous mutations of the FAH gene, namely c.634delT (p.L212Wfs*20) and c.455G>A (p.W152X), were detected in the proband, which were both predicted to be pathogenic and were inherited from her father and mother, respectively.@*CONCLUSION@#For children with tyrosinemia type I, detection of urine succinylacetone by gas phase mass spectrometry can be negative. The diagnosis of tyrosinemia type I must rely on genetic testing and/or enzymatic assaying.

Tirosinemia de tipo 1 en un lactante / Type 1 Tyrosinemia in an infant

Se describe el caso clínico de una paciente de 2 meses de edad, quien nació a término y normopeso; se alimentaba con lactancia materna exclusiva y tuvo antecedente de 2 ingresos previos (anemia severa y catarro común). Fue hospitalizada en el Servicio de Terapia Intensiva del Hospital Infantil Sur Dr Antonio María Béguez César por presentar edemas generalizados y ascitis, con evolución rápida hacia un cuadro de insuficiencia hepática aguda. Las pruebas metabólicas de orina y sangre permitieron confirmar el diagnóstico de tirosinemia de tipo 1. A pesar de brindarle la atención requerida, la paciente evolucionó desfavorablemente.

The case report of a 2 months of age patient is described who was born at term and normal in weight; she fed with exclusive breast feeding and she had a history of 2 previous admissions (severe anemia and common cold). She was hospitalized in the Intensive Therapy Service of Dr Antonio María Béguez Caesar Southern Pediatric Hospital due to widespread edemas and ascites, with a fast clinical course to an acute liver failure. The metabolic tests of urine and blood allowed to confirm the diagnosis of type 1 tyrosinemia. In spite of offering her the required care, the patient had an unfavourable clinical course.

Measurement of Succinylacetone Using HPLC-Tandem Mass Spectrometry and Establishment of a Cut-off Value

BACKGROUND: Newborn screening of tyrosinemia type 1 is important for identifying infants at risk for developing this disease before life-threatening symptoms occur. It is difficult to differentiate between tyrosinemia type 1 and transient neonatal tyrosinemia (TNT) by analyzing tyrosine alone. Thus, succinylacetone must be analyzed. In this study, we measured succinylacetone in dried blood spot (DBS) by HPLC-tandem mass spectrometry (HPLC-MS/MS) and established cut-off values. METHODS: We used the hydrazine derivatization method to measure succinylacetone in 127 DBSs showing normal results in the newborn screening test and 93 DBSs showing increased tyrosine levels. We established cut-off values using the 99.9th percentile value or median+5 standard deviation value. RESULTS: Succinylacetone levels determined by our method were well-correlated with the results recommended by the Centers for Disease Control and Prevention for proficiency testing (r=0.9968). The succinylacetone levels in normal newborn DBSs were significantly lower than those in DBSs with high tyrosine levels (P < 0.001). The cut-off values were calculated to be 1.3 µM from the results of 127 normal DBS samples and 2.2 µM from 220 DBSs, including in 93 newborns with TNT. CONCLUSIONS: Measurement of succinylacetone in DBSs by HPLC-MS/MS is useful in individuals with increased tyrosine concentrations and can be used for rapid differential diagnosis of tyrosinemia when an appropriate cut-off value is established.

Mutation analysis of FAH gene in patients with tyrosinemia type 1 / 中华儿科杂志

<p><b>OBJECTIVE</b>To investigate the clinical features and mutations of the FAH gene.</p><p><b>METHOD</b>Clinical records of two cases were collected, and diagnosis was made according to the diagnostic criteria of the International Organization for Rare Disorders (NORD). Genomic DNA was extracted from peripheral blood leukocytes with QIAamp DNA Mini Kit. The DNA extracts were subjected to direct sequencing for 14 exons together with adjacent fragments of FAH gene using ABI Prism 3730 Genetic Analyzer (Applied Biosystems, Foster City, CA) after PCR based on genomic DNA. The mutation source was verified by analyzing parents' exons corresponding to patients' mutation exons. The homology between human FAH enzyme and that of other species was surveyed using software Clustal X(European Bioinformatics Institute, Hinxton, Saffron Walde, UK). Polyphen (Polymorphism Phenotyping), available online, were used to predict possible impact of an amino acid substitution on structure and function of FAH enzyme. Polyphen calculates position-specific independent counts (PISC) scores for two amino acid variants in polymorphic position. A PISC scores that differ by > 2 were regarded as indicating the probability of damaging variants.</p><p><b>RESULT</b>Patient 1 was a 5 months and 21 days-old boy who suffered from persistent diarrhea, hepatomegaly, ascites; Alpha-fetoprotein > 1210 µg/L, levels of tyrosine in blood and succinylacetone in urine were 110.8 µmol/L and 83.7 µmol/L. His sister suffered from tyrosinemia type 1. Direct sequencing showed a G to A transition in CDS position 455 and 1027. He was compound heterozygous for the mutation c.455G > A/c.1027G > A, which predicts a change from tryptophan to a stop codon (TGG > TAG) at position 152 (W152X) and a change from glycine to arginine (GGG > AGG) at position 343 respectively. Patient 2 was a 6 year and 1 month-old girl with late-onset rickets who had signs of hepatosplenomegaly, rachitic rosary, windswept knees. Hypophosphatemia and alkaline phosphatase 1620 IU/L were detected. Alpha-fetoprotein 412.8 µg/L, levels of tyrosine in blood and succinylacetone in urine were 835.8 µmol/L and 27.48 µmol/L. Rickets did not improve after administration of calcium and vitamine D3. She is homozygous for the mutation c.1027G > A/c.1027G > A, which predicts G343R. The parents were mutation carriers. Analysis by Clustal X on the alignment of amino acids residual reservation among different species showed that the locative amino acid was highly conserved. Polyphen software predicted G343R was probably damaging (PISC score 3.235).</p><p><b>CONCLUSION</b>Children with tyrosinemia type 1 can have manifestations of persistent diarrhea or late-onset rickets. Physical examination can reveal hepatosplenomegaly, laboratory tests indicate markedly elevated serum concentration of alpha-fetoprotein and alkaline phosphatase in plasma and succinylacetone in urine, other members in family may have tyrosinemias or parents are consanguineous. Mutations c.455G > A and c.1027G > A can be detected in FAH gene of Chinese children.</p>

Evolución clínica de pacientes chilenos con tirosinemia tipo I tratados con 2-(2-nitro-4-trifluorometilbenzoil)-1,3-ciclohexanediona (NTBC) / Clinical follow up of Chilean patients with tyrosinemia type 1 treated with 2-(2-nitro-4-trifluoromethylbenzoyl)-1,3-ciclohexanedione (NTBC)

Background: Tyrosinemia type I is an inborn error of metabolism due to deficiency of fumarilacetoacetase. Acute presentation is with liver failure, hypophosphatemic rickets and peripheral neuropathy. Chronic presentation is with visceromegaly and subclinical rickets. The most severe complications are hepatic cancer and acute neurological crises. Without treatment, tyrosinemia type 1 is fatal. In 1992 treatment for tyrosinemia type 1 with 2-(2-nitro-4-trifluoromethybenzoyl)-1,3-ciclohexanedione (NTBC) was proposed. A clinical response was reported in 90% of patients. In cases that did not respond, a successful liver transplantation was performed, reducing mortality to 5%. Aim: To report the follow up of 12 patients treated with NTBC. Patients and Methods: Review of clinical records of 12 Chilean cases treated with NTBC at the Instituto de Nutrición y Tecnología de los Alimentos (INTA) from January 2004 until June 2010. Results: In all patients, a rapid metabolic control was achieved. Two patients developed hepatocarcinoma. One of these patients died and one was successfully treated with liver transplantation. One patient died after receiving a liver transplantation. Nine patients have at present good liver function, but 2 had peripheral neuropathy due to late diagnosis and discontinuing NTBC treatment. Conclusions: Treatment with NTBC allows metabolic normalization in tyrosinemia type 1, prevents liver cirrhosis and hepatic cancer, improving survival rates and quality of life in the patients. Neonatal screening is essential for the early diagnosis of this treatable disease, that otherwise may be lethal.

Analysis of clinical data and genetic mutations in three Chinese patients with tyrosinemia type I / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To analyze clinical data and gene mutations in 3 Chinese patients with tyrosinemia type I, and to explore the correlation between genotypes and phenotypes.</p><p><b>METHODS</b>Three patients suspected with tyrosinemia I were tested by tandem mass spectrometry for the level of tyrosine, phenylalanine and succinylacetone in the blood, and by gas chromatography-mass spectrometry to determine the level of succinylacetone and organic acid in their urine. With the diagnosis established, the FAH gene was analyzed with polymerase chain reaction (PCR) and direct sequencing.</p><p><b>RESULTS</b>Two patients had acute onset of the disease, while another had subacute onset of the disease, with features including hepatomegaly and remarkably increased tyrosine and succinylacetone in the blood. Five mutations were detected in the FAH gene, which included c.455G>A (W152X), c.520C>T (R174X), c.974_976delCGAinsGC, c.1027 G>A (G343R) and c.1100 G>A (W367X), among which c.455G>A (W152X), c.974_976delCGAinsGC and c.1100 G>A (W367X) were not reported previously.</p><p><b>CONCLUSION</b>Tyrosinemia type I may be effectively diagnosed with the level of tyrosine and succinylacetone by tandem mass spectrometry and succinylacetone in the urine by gas chromatography mass spectrometry. Detection of underlying mutations mutations will be helpful for genetic counseling and further research.</p>

Compound mutations (R237X and L375P) in the fumarylacetoacetate hydrolase gene causing tyrosinemia type I in a Chinese patient / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Mutations in fumarylacetoacetate hydrolase (FAH) gene can lead to tyrosinemia type 1 (HT1), a relatively rare autosomal recessive disorder. To date, no molecular genetic defects of HT1 in China have been described. We investigated a Chinese family with a HT1 child to identify mutations in FAH.</p><p><b>METHODS</b>DNA sequencing was used for mutations screening in FAH gene. Real-time polymerase chain reaction (PCR) was performed to determine the FAH gene expression level. To confirm the presence of degradation by the nonsense-mediated mRNA decay pathway (NMD), the fragments containing R237X mutations were analyzed by primer introduced restriction analysis-polymerase chain reaction (PIRA-PCR) and cDNA sequencing. Finally, the effects of the mutations reported in this study were predicted by online softwares.</p><p><b>RESULTS</b>A boy aged 3 years and 8 months was diagnosed clinically with HT1 based on his manifestations and biochemical abnormalities. Screening of FAH gene revealed two heterozygous mutations R237X and L375P transmitted from his mother and father respectively. In this pedigree, the amount of FAH mRNA relative to a healthy control was 0.44 for the patient, 0.77 for his mother and 1.07 for his father. Moreover, both PIRA-PCR and cDNA sequencing showed significant reduction of the FAH mRNA with R237X nonsense mutation. The missense mutation of L375P was not reported previously and prediction software showed that this mutation decreased the stability of protein structure and affected protein function.</p><p><b>CONCLUSIONS</b>This is the first case of HT1 analyzed by molecular genetics in China. The R237X mutation in FAH down- regulates the FAH gene expression, and the L375P mutation perhaps interrupts the secondary structure of FAH protein.</p>

Application of succinylacetone levels measurement in the blood and urine in the diagnosis of tyrosinemia type 1 / 中华儿科杂志

<p><b>OBJECTIVE</b>To establish the diagnostic method of tyrosinemia type 1 and evaluate its value, the succinylacetone levels in the blood of suspected patients with tyrosinemia were tested by tandem mass spectrometry, and the succinylacetone in the urine was tested by gas chromatography-mass spectrometry.</p><p><b>METHOD</b>A total of 190 patients suspected of having tyrosinemia, were tested by tandem mass spectrometry for measurement of the level of succinylacetone in the blood, and detected by gas chromatography-mass spectrometry for measurement of the level of succinylacetone and organic acid in the urine. The method of measuring the level of succinylacetone in blood by tandem mass spectrometry as follows: After the diameter of 3 mm dry blood spots were punched into wells of 96-well plate, 100 µl 80% acetonitrile were added into each well, which contained hydrazine monohydrate and the internal standard of succinylacetone. The supernatant fluid were transferred to another 96-well plate and dried under heated nitrogen, after the plate was incubated for 30 min at 65°C. The residual hydrazine reagent was removed by addition of 100 µl methanol to each well and evaporated under heated nitrogen. The mobile phase (80% acetonitrile) was added to each well and 20 µl samples were tested by tandem mass spectrometry. The diagnostic terms were the clinical manifestation and the high level of succinylacetone in both blood and urine.</p><p><b>RESULT</b>Eleven patients were diagnosed as tyrosinemia type 1, with 9 males and 2 females. Their ages ranged from 2 months to 6 years. The succinylacetone levels in the blood of the patients were remarkably increased (7.26-31.09 µmol/L), with an average of (14.2 ± 7.8)µmol/L. Seven patients were tested for the level of succinylacetone in the urine by gas chromatography-mass spectrometry, and 4 were positive and 3 negative. Their tyrosine levels in the blood were 190-543 µmol/L(Normal: 20 - 100 µmol/L), with an average of (327.3 ± 125.8) µmol/L. All the patients presented the symptoms of hepatomegaly. Among them, 9 patients died and 2 patients were improved after treatment.</p><p><b>CONCLUSION</b>The higher levels of succinylacetone in the blood or urine is a remarkable evidence for the diagnosis of tyrosinemia type 1. Determination of succinylacetone in the dry blood spots using tandem mass spectrometry was a good method for diagnosis of tyrosinemia type 1. To test succinylacetone in urine by gas chromatography-mass spectrometry may yield a false-negative result for tyrosinemia type 1.</p>

Tyrosinemia type 1: clinical and biochemical analysis of cases with poor treatment outcome

Tyrosinemia Type I [TT1] is a metabolic disorder with impaired activity of fumarylacetoacetate hydrolase enzyme. The causes of death are liver failure, pseudo porphyric crisis and hepatocarcinoma. The treatment is based on diet restriction, liver transplantation and the NTBC. Aim: To review the clinical presentation, biochemical analysis and expose the causes of failure of treatment in 3 patients with TT1. By studying the clinical and biochemical data of 3 dead patients with TT1 [part of the total 15 patients with the same diagnosis], during [October 2001 to October 2009].The diagnosis was established by high tyrosin in the blood and succinylacetone in the urine. Monitoring was based on the combination of liver imaging, and alpha feto protein as tumor marker. Two patients were treated by NTBC and diet restriction [patients 1 and 2] while the 3rd patient was treated by diet restriction only. Overall survival rate was 80% [85.7% in those treated by NTBC]. The age at onset was respectively 8, 5 and 1.5 months .The age at diagnosis was 40, 6 and 6 months. All three patients were presented with severe liver failure. [PT ranged from 21% to 24%], patient 1 was treated with NTBC for 4 months and died after 2 months of stopping NTBC. The second patient did not respond to NTBC and died after 5 months of treatment. The third patient died after 2 months of treatment. A. Poor prognosis in patient 1 and 2 could be explained by [1] The dose was less than 2mg/kg/d [2] Late diagnosis in patient 1. [3] Difficulty of management and monitoring. B. Poor prognosis in patient 3 was on diet restriction as in the literature. C. Slow decrease of alpha feto protein can explain the possibility of hepatocarcinoma in patient 1 and 2 but the duration of the treatment was short to conclude, the increase in patient 3 is well known as a part of hepatocarcinoma mechanism. [1] Early diagnosis and starting NTBC with diet restriction give good prognosis. [2] Starting neonatal metabolic screening

Estresse oxidativo em porfiria hepâtica experimental disparadapor succinilacetona - urn inibidor da âcido 5-aminolevulinico desidratase / Oxidative stress in experimental hepatic porphyria triggered bysuccinylacetone — an inhibitor of 5-aminoluvulinic acid dehydratase

Para otimizar urn modelo experimental para o estudo do desbalanço redox em porfirias relacionadas ao acúmulo de ácido 5-aminolevulinico-(ALA), via inibição da ALA desidratase-(ALA-D), ratos foram tratados com o éster metílico de succinilacetona-(SAME), um catabólito da tirosina que inibe fortemente a ALA-D, mimetizando o estado metabólico observado nos portadores de porfirias e tirosinemias. Estabeleceram-se modelos de tratamento agudo por 36 e 18 h. No primeiro, os animais receberam 3 injeções de SAME (10, 40 ou 80 mg/kg, grupos All-IV). No segundo, os animais receberam 3 injeções de 40 mg/kg de SAME, ALA ou éster metílico de ALA (grupos BII-IV), ALA:SAME (30:10 mg/kg, grupo BV), ou 10 mg/kg SAME (grupo BVI). Paralelamente, avaliou-se se os sintomas neurológicos característicos das porfirias decorriam de danos oxidativos mitocondriais. Para isso, aplicou-se uma tecnologia óptica para medidas da difusão da depressão cortical que determinou a oxigenação e o estado redox do cit c em mitocôndrias do córtex cerebral de ratos submetidos ao tratamento crônico com ALA (40 mg/kg), SAME (10 e 40 mg/kg) e ALA:SAME (30:10 mg/kg), a cada 48 h, durante 30 dias. Tratamento agudo/36 h: Os níveis de ALA no plasma, fígado, cérebro e urina e o clearance renal do ALA aumentaram nos grupos tratados. A atividade de ALA-D e a coproporfirina urinaria reduziram. A marcação para proteínas carboniladas, ferro e ferritina aumentou no fígado e cérebro dos grupos tratados, especialmente no All. Os níveis de malondialdeído hepática aumentaram no grupo AIV. A razão GSH/GSH+GSSG e a atividade de GPx cerebrais aumentaram nos grupos AIV e AIII, respectivamente. Consistentemente com estes dados indicando um desbalanço oxidativo induzido pelo SAME, alterações mitocondriais e citosólicas ultraestruturais foram reveladas, especialmente no fígado./Tratamento agudo/18 h: Os níveis de ALA plasmáticos aumentaram nos grupos tratados, exceto em BIV. 0 grupo Bll mostrou aumento dos níveis hepáticos...

To optimize an experimental model for studying redox imbalance in porphyrias related to 5-aminolevulinic acid (ALA) accumulation through the inhibition of ALA dehydratase (ALA-D), rats were treated with methyl ester of succinylacetone (SAME), a tyrosine catabolite that strongly inhibits ALA-D, what mimics the metabolic state observed in patients suffering from porphyrias and tyrosinemias. Models of acute treatment were established during 36 and 18 h. In the first model, animals received 3 injections of SAME (10, 40 or 80 mg/kg, groups All-IV). In the second model, animals received 3 injections of 40 mg/kg SAME, ALA or methyl ester of ALA (groups BII-IV), ALA:SAME (30:10 mg/kg, group BV), or 10 mg/kg SAME (group BVI). Concomitantly, we evaluated if the neurologic symptoms characteristics of porphyrias were a consequence of the oxidative mitochondria! impairment. For this, an optical technology for the measurement of cortical spreading depression was applied. This techonology determined the cerebral oxygenation and the redox state of cit c in mitochondria of the cerebral cortex of rats submitted to a chronic treatment with ALA (40 mg/kg), SAME (10 and 40 mg/kg) and ALA:SAME (30:10 mg/kg), alternate days, during 30 days. Acute treatment/36 h: ALA levels in plasma, liver and urine and clearance of renal ALA increased in treated groups. ALA-D activities and urinary coproporphyrin were found to be decreased. Liver and brain proteins carbonyl, iron and ferritin were higher in the liver of treated groups, especially in All. Liver j malondialdehyde levels were higher in group AIV. Cerebral GSH/GSH+GSSG ratio and GPx activities increased in groups AIV and AIII, respectively. Consistently with these data indicating SAME-induced oxidative imbalance, mitochondrial and cytosolic ultrastructural changes were revealed, especially in the liver. Acute treatment/18 h: Plasma ALA levels increased in all treated groups but BIV. Group BII showed increased hepatic ALA levels…

Neonatal presentation of a rare metabolic liver disease.

Tyrosinemia is a rare paediatric metabolic liver disorder. A 15-days-old neonate born of a third degree consanguineous marriage presented with jaundice due to tyrosinemia, which progressed to fatal hepatic encephalopathy. The diagnosis was based on very high alpha-fetoprotein level, with urine aminoacidogram revealing tyrosine spot and liver biopsy depicting cirrhosis. Very early neonatal presentation and rapid progression were the unusual features of this case.

Cytomegalovirus infection in twin pregnancy and coincidence of type i tyrosinemia in one of twins

Cytomegalovirus [CMV] is the most common cause of congenital infection. Although most of the involved neonates are asymptomatic but virus can cause a range of problems from mild to severe illness with involvement of different organs like central nervous system, gastrointestinal and liver. Proneness to CMV is very high [up to 1% of neonates]. In the other hand trosinemia type I is a rare metabolic disorder with involvement of liver, neurologic, bone and other organs. A 3-month-old infant, product of twin pregnancy was hospitalized because of jaundice, FTT, hepatomegaly and sepsis. The other twin showed normal growth with no problems. Work up for cholestasis and FTT was suggestive of two different entities. Polymerase chain reaction for CMV in liver tissue and serum was positive. Meanwhile laboratory findings for metabolic disorder led to the diagnosis of type 1 tyrosinemia. The other twin was infected with CMV too. Although coexistence of two causes for cholestasis is very rare, it is sometimes necessary to study more to rule out other entities like metabolic disease including tyrosinemia [if any symptoms exist]

Unusual dendritic keratitis.

Bilateral pseudo-dendritic keratitis in infancy can be due to tyrosinemia, a rare metabolic disorder. Ocular involvement may be the earliest presenting manifestation of this disease. Early diagnosis is essential because dietary modifications can result in complete reversal of the manifestations of this disorder. This disease must be suspected in all cases of non-responsive dendritic keratitis in the pediatric age group, especially if it is associated with cutaneous lesions such as patmoplantar keratosis. Serum tyrosine levels must be done in these cases.

The etiologies of neonatal cholestasis / 소아과

Any infant noted to be jaundiced at 2 weeks of age should be evaluated for cholestasis with measurement of total and direct serum bilirubin. With the insight into the clinical phenotype and the genotype-phenotype correlations, it is now possible to evaluate more precisely the neonate who presents with conjugated hyperbilirubinemia. Testing should be performed for the specific treatable causes of neonatal cholestasis, specifically sepsis, galactosemia, tyrosinemia, citrin deficiency and endocrine disorders. Biliary atresia must be excluded. Low levels of serum gamma-glutamyl transferase in the presence of cholestasis should suggest progressive familial intrahepatic cholestasis type 1, 2, or arthrogryposis- renal dysfunction-cholestasis syndrome. If the serum bile acid level is low, a bile acid synthetic defect should be considered. Molecular genetic testing and molecular-based diagnostic strategies are in evolution.

Richner Hanhart syndrome.

Richner Hanhart syndrome is a rare inherited disorder involving the metabolism of tyrosine, a semi-essential amino acid and it should be considered in the differential diagnosis of a child presenting with ocular and skin lesions. We report a case of Richner Hanhart syndrome in a 19-month-old child, who presented with ocular and skin lesions.