Serum procalcitonin as a marker of neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD).

BACKGROUND: Neonatal Intrahepatic Cholestasis (NICCD), as the early-age stage of Citrin deficiency involving liver dysfunction, lacks efficient diagnostic markers. Procalcitonin (PCT) has been identified as a biomarker for infection as well as various organ damage. This study aimed to explore the potential of PCT as a biomarker for NICCD. METHODS: In a single-center retrospective case-control study. Serum PCT concentrations before and after treatment of 120 NICCD patients, as the study group, were compared to the same number of cholestatic hepatitis patients, as the control group. The potential value of PCT to discriminate NICCD from control disease was further explored using Receiver Operating Characteristic (ROC) curve analysis and compared to those of other inflammatory markers. RESULTS: There was a significantly higher level of PCT in NICCD patients than in the control group. PCT concentrations were only weakly correlated with neutrophil counts and CRP levels (p ˂ 0.05). At a cut-off value of 0.495 ng/mL, PCT exhibited a significantly higher diagnostic value compared to other inflammatory markers for discriminating NICCD from the control, with a sensitivity of 90.8 % and specificity of 98.3 %. CONCLUSION: PCT might be used as an initial biomarker to discriminate children with NICCD from another hepatitis disease.

Dietary Management, Clinical Status and Outcome of Patients with Citrin Deficiency in the UK.

BACKGROUND: Little is known about the optimal dietary treatment for citrin deficiency. Our aim is to describe the management of UK citrin deficiency patients. METHODS: A longitudinal retrospective review was performed. Data were collected from medical records on presenting signs and symptoms, dietary management and clinical outcome. RESULTS: data were collected on 32 patients from 21 families. 50% were females (16/32). Median age at diagnosis was 4 y (5 days-35 y) with 12 patients diagnosed in the neonatal period with neonatal intrahepatic cholestasis (NICCD), eight later in childhood (FTTDCD) and 12 by family screening based on index cases from five families. No patient had adult-onset type II citrullinemia. The patient age at the time of data collection was a median of 11 y (1-44 y). 91% (29/32) of patients had normal physical and neurological development, 47% (15/32) experienced recurrent unexplained abdominal pain and 9% (3/32) episodes of hypoglycaemia. Siblings had different phenotypes (5 families had > 1 affected patient). Most patients preferred high protein foods, limiting sugar-containing foods. Only 41% (13/32) were prescribed a low CHO, high protein, high fat diet (restriction varied) and two used medium chain triglyceride (MCT) supplements. No patient was prescribed drug therapy. Twenty-five per cent (8/32) of patients were underweight and 41% (13/32) had height <-1 z-scores. CONCLUSIONS: patients presented with various phenotypes, symptoms and suboptimal growth. Symptoms and biochemical markers improved with age, but height remained low in some. More research is necessary to assess the effectiveness of dietary approaches in improving clinical outcomes and symptoms in citrin deficiency.

[Newborn screening program and blood amino acid profiling in early neonates with citrin deficiency].

Objective: To investigate the profiles of blood amino acid and acylcarnitine in early neonates with neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) and the sensitivity of newborn screening, and to explore potential biochemical metabolic markers for newborn screening program. Methods: Amino acid and acylcarnitine profiles in dried blood spots of newborn screening program were analyzed by tandem mass spectrometry (MS/MS). A total of 158 651 neonates born in Guangzhou from January 1, 2015 to June 30, 2019 were enrolled in this newborn screening program, and additionally 55 patients with NICCD confirmed by SLC25A13 gene analysis in Guangzhou Women and Children Medical Center were included in this study. NICCD screen-positive was defined as the cutoff value of citrulline (Cit) ≥ 30 µmol/L. The values of blood sampling time of the true positive group and those of the false negative group were compared by t-test. The levels of amino acid and acylcarnitine among different groups, including true positive group (Cit≥30 µmol/L), false negative group (Cit 21-<30 µmol/L and Cit<21 µmol/L) and the normal control group, were analyzed by F test, respectively. Results: Among 158 651 neonates, 39 neonates were positive for NICCD screening. Three of them were confirmed NICCD and 4 cases were found to be false negatives. The positive predictive value was 7.7% and the sensitivity was about 43.0%. Among 55 patients with NICCD, 18 cases (18/55, 32.7%) were true positives and 37 cases (37/55, 67.3%) were false negatives based on the cutoff value of citrulline in the dried blood spots for newborn screening. The blood sampling time was significantly different between true positive group and false negative group ((4.28±1.6) vs. (2.98±0.74) d, t=4.06, P<0.01). The increased levels of tyrosine((176.0±98.4) µmol/L), methionine ((37.0±26.9) µmol/L) and phenylalanine ((133.0±80.9)µmol/L) in Cit≥30 µmol/L group (n=18) were significantly different as compared with those in the other three groups, respectively (F=117.0, 58.5, 135.0, P<0.01). The levels of arginine ( (10.0±9.2) , (11.0±9.3) , (9.0±17.8) µmol/L), valine ( (119.0±29.8) , (107.6±14.1) , (102±68) µmol/L) and leucine ( (167.0±37.1) , (161.0±37.7) , (163.5±180.6) µmol/L) were not statistically significant among groups of Cit≥30 µmol/L(n=18), Cit21-<30 µmol/L(n=7) and Cit<21µmol/L(n=30,P>0.05), but they were significantly higher than those of the normal control group ((4±3), (78±21), (114.0±31.5) µmol/L, n=1 000), respectively(F=30.1, 23.0, 29.8, P<0.01). Alanine (Ala) ( (150±50) , (156.0±30.2), (168±105), (152±52) µmol/L) levels showed no significant difference (F=0.86, P>0.05) but the ratios of Ala/Cit (1.52±1.44, 6.82±1.56, 12.06±7.71, 19.42±6.27) decreased significantly among the four groups (F=69.0, P<0.05). The acylcarnitine levels showed no statistically significant results among the different groups (P>0.05). With Cit≥30 µmol/L and Ala/Cit<7.5 as cutoff values, the number of screen-positive cases reduced from 39 to 22 cases with no additional false negative case. With Cit≥21 µmol/L and Ala/Cit<7.5 as cutoff values the number of screen-positive cases increased to 117 cases with 1 additional true positive. Conclusions: The profiles of blood amino acid in early neonates with NICCD present the increased levels of multiple amino acids including citrulline, tyrosine, methionine and phenylalanine, and decreased ratio of Ala/Cit. Taking citrulline and ratio of Ala/Cit as screening markers can improve the positive predictive value appropriately. The limited sensitivity of NICCD newborn screening may be related to early blood sampling time.

A 6-Year-Old Child With Citrin Deficiency and Advanced Hepatocellular Carcinoma.

We report the case of a 6-year-old boy with citrin deficiency and advanced hepatocellular carcinoma diagnosed by using imaging. He exhibited intrahepatic cholestasis 2 days after his birth and was misdiagnosed with inspissated bile syndrome at that time. The symptoms of jaundice spontaneously resolved when he was 5 months old. However, his transaminase levels remained elevated for ∼6 years, for which he received no treatment. He preferred a high-protein, high-fat, low-carbohydrate diet, which has been observed in many patients with citrin deficiency, but no clinical features of adult-onset type II citrullinemia were observed. At the age of 6 years, he was admitted to our hospital with a nonviral infection and high α-fetoprotein level; results from an abdominal MRI and computed tomography revealed multiple tumors in the liver. Because of his history of intrahepatic cholestasis in the neonatal period, he was suspected to have citrin deficiency. A genetic analysis of solute carrier family 25, member 13 revealed the presence of a homozygous 851del4 mutation, and a diagnosis of citrin deficiency was made. The patient did not qualify for liver transplantation and died 2 months later, after discharge from our hospital. Thus, this case reveals that not all patients with neonatal intrahepatic cholestasis spontaneously and totally improve, and this case is used to emphasize that patients with neonatal intrahepatic cholestasis should be managed carefully, especially in the stage of failure to thrive and dyslipidemia caused by citrin deficiency, which may lead to advanced hepatocellular carcinoma.

[Identification of a homozygous ASS1 mutation in a child with citrullinemia type â with high-melting curve method].

OBJECTIVE: To carry out rapid genetic diagnosis for a child affected with citrullinemia type Ⅰ. METHODS: Peripheral venous blood samples were obtained from the two-day-old child and his parents as well as 100 healthy controls. Serum ammonia and citrulline was determined by biochemical test and tandem mass spectrometry. Sixteen pairs of primers were designed for high-resolution melting (HRM) analysis of all exons and adjacent intronic sequences of the ASS1 gene in the proband, parents and healthy controls. Suspected mutations were confirmed by DNA sequencing, while the mRNA transcripts of the ASS1 gene were determined by reverse transcription (RT)-PCR. Functional impact of the mutation sites was predicted with PolyPhen-2 and SIFT Blink software. RESULTS: Blood ammonia and citrulline of the proband have respectively reached 286 µmol/L and 487.69 µmol/L, which far superseded the normal values. HRM analysis and DNA sequencing have identified in the child a homozygous c.380G>A (p.R127Q) mutation in exon 6 of the ASS1 gene, in addition with a homozygous IVS8+60G>A substitution in intron 8, while his parents were heterozygous carriers for both mutations. RT-PCR assay indicated that the IVS8+60G>A mutation did not result in abnormal splicing of the ASS1 gene transcripts. Bioinformatic analysis suggested that the site for p.R127Q was conserved among 45 species of vertebrates and may play a crucial role in citrulline metabolism. CONCLUSION: The severe urea cycle disorder in the proband was probably due to the compound homozygous R127Q and IVS8+60G>A mutations of the ASS1 gene.

Biochemical markers and neuropsychological functioning in distal urea cycle disorders.

Urea cycle disorders often present as devastating metabolic conditions, resulting in high mortality and significant neuropsychological damage, despite treatment. The Urea Cycle Disorders Longitudinal Study is a natural history study that collects data from regular clinical follow-up and neuropsychological testing. This report examines links between biochemical markers (ammonia, glutamine, arginine, citrulline) and primary neuropsychological endpoints in three distal disorders, argininosuccinic acid synthetase deficiency (ASD or citrullinemia type I), argininosuccinic acid lyase deficiency (ASA or ALD), and arginase deficiency (ARGD). Laboratory results and test scores from neuropsychological evaluations were assessed in 145 study participants, ages 3 years and older, with ASD (n = 64), ASA (n = 65) and ARGD (n = 16). Mean full scale IQ was below the population mean of 100 ± 15 for all groups: (ASD = 79 ± 24; ASA = 71 ± 21; ARGD = 65 ± 19). The greatest deficits were noted in visual performance and motor skills for all groups. While ammonia levels remain prominent as prognostic biomarkers, other biomarkers may be equally valuable as correlates of neuropsychological functioning. Cumulative exposure to the biomarkers included in the study proved to be highly sensitive indicators of neuropsychological outcomes, even when below the cut-off levels generally considered toxic. Blood levels of biomarkers obtained on the day of neuropsychological evaluations were not correlated with measures of functioning for any disorder in any domain. The importance of cumulative exposure supports early identification and confirms the need for well-controlled management of all biochemical abnormalities (and not just ammonia) that occur in urea cycle disorders.

Metabolically based liver damage pathophysiology in patients with urea cycle disorders - A new hypothesis.

The underlying pathophysiology of liver dysfunction in urea cycle disorders (UCDs) is still largely elusive. There is some evidence that the accumulation of urea cycle (UC) intermediates are toxic for hepatocyte mitochondria. It is possible that liver injury is directly caused by the toxicity of ammonia. The rarity of UCDs, the lack of checking of iron level in these patients, superficial knowledge of UC and an underestimation of the metabolic role of fumaric acid, are the main reasons that are responsible for the incomprehension of the mechanism of liver injury in patients suffering from UCDs. Owing to our routine clinical practice to screen for iron overload in severely ill neonates, with the focus on the newborns suffering from acute liver failure, we report a case of citrullinemia with neonatal liver failure and high blood parameters of iron overload. We hypothesize that the key is in the decreased-deficient fumaric acid production in the course of UC in UCDs that causes several sequentially intertwined metabolic disturbances with final result of liver iron overload. The presented hypothesis could be easily tested by examining the patients suffering from UCDs, for liver iron overload. This could be easily performed in countries with a high population and comprehensive national register for inborn errors of metabolism. CONCLUSION: Providing the hypothesis is correct, neonatal liver damage in patients having UCD can be prevented by the supplementation of pregnant women with fumaric or succinic acid, prepared in the form of iron supplementation pills. After birth, liver damage in patients having UCDs can be prevented by supplementation of these patients with zinc fumarate or zinc succinylate, as well.

Bile acid profiles in neonatal intrahepatic cholestasis caused by citrin deficiency.

BACKGROUND: Neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) is characterized by conjugated hyperbilirubinemia and increased plasma bile acid concentrations. However, the underlying mechanisms remain unclear. We established a liquid chromatography tandem mass spectrometry (LC-MS/MS) method for simultaneously quantifying plasma bile acids and examined bile acid profiles in NICCD infants. METHODS: We measured 15 bile acids within 15min and found a wide linear range for individual bile acids. RESULTS: The within-run and run-to-run CV of all bile acids was 1.2-10.9% and 3.1-10.8%, respectively, with a mean recovery of 90.5-112.6%. Compared to infants with citrullinemia without mutations in SLC25A13 (non-NICCD), NICCD infants showed increased plasma total bile acid concentrations (mean: 201 vs. 42µM, p<0.001), with a distinct bile acid profile characterized by increased conjugated primary bile acid concentrations. The calculated ratios, including primary/secondary bile acid (714 vs. 235, p<0.05) and conjugated/free bile acid (371 vs. 125, p<0.05) ratios, were higher in NICCD infants. The area under receiver operating characteristic curve for conjugated/free bile acid ratio to identify infants with NICCD was 0.871 (95% confidence interval, 0.713-1.0). CONCLUSIONS: Together, our findings indicated plasma bile acid profile as a potential noninvasive diagnostic biomarker for NICCD.

Blood glucose and insulin and correlation of SLC25A13 mutations with biochemical changes in NICCD patients.

Neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) is a hereditary metabolic disease arising from biallelic mutations of SLC25A13. This study aimed to explore the characteristics of fasting blood glucose (FBG), fasting insulin (FINS) and C-peptide (C-P) levels in NICCD infants, analyze their SLC25A13 genetic mutations and further discuss the correlation between SLC25A13 genetic mutations and biochemical changes. Seventy-two cases of infants with cholestasis disease were gathered. Among them, 36 cases with NICCD diagnosis were case group. Meanwhile, 36 cases with unknown etiology but excluded NICCD were control group. FBG, FINS, C-P, ALT, AST, GGT, ALP, TG, HDL-C, LDL-C and Non-HDL-C were collected from all subjects, and DNA was extracted from venous blood for SLC25A13 mutations detection. The incidence of hypoglycemia was 3% in NICCD group. There were no significant statistical difference of FBG, FINS and C-P between NICCD and INC groups ( P > 0.05). ALT, LDL-C and Non-HDL-C levels in NICCD group were lower than the INC group, while SLC25A13 mutations were associated with the level of GGT ( P < 0.05). Ten different SLC25A13 genetic mutations were detected, among which, 851del4, IVS16ins3kb, IVS6+5 G > A and 1638ins23 mutations made up 82% of all mutations. The incidence of hypoglycemia may be higher in small gestational age infants with NICCD. Low LDL-C may be one of the characteristics of dyslipidemia in NICCD infants. There was a correlation between SLC25A13 gene mutations distribution and the GGT level, but the meaning of this finding remains to be further in-depth study. Impact statement This study aims to compare FBG, FINS, C-P, other biochemical and clinical manifestations between NICCD and non-NICCD infants, and discuss differential diagnosis of NICCD and INC beyond the genetic analysis. And investigate the correlation between SLC25A13 genetic mutations and biochemical changes. This work presented that incidence of hypoglycemia may be higher in small gestational age infants with NICCD. Low LDL-C may be one of the characteristics of dyslipidemia in NICCD infants. There was a correlation between SLC25A13 gene mutations distribution and the GGT level.

Intestinal dysfunction in the critical trauma patients - An early and frequent event.

BACKGROUND: Small-bowel dysfunction exerts a relevant prognostic impact in the critically ill patients. Citrullinemia has been used in the evaluation of the intestinal function and it is considered an objective parameter of the functional enterocyte mass. Present study proposes to determine the intestinal dysfunction prevalence and the citrullinemia kinetic profile in severe trauma patients and to investigate its correlation with severity indicators and clinical outcome. METHODS: A prospective study including 23 critical trauma patients was performed. Aminoacidemias were quantified, by ion exchange chromatography, at the admission and at the first and third days. Severity and outcome parameters were registered. RESULTS: In severe trauma patients, severe hypocitrullinemia (< 20 µmol/L) prevalence at admission was high (69.6%) and mean citrullinemia was low (19.5 ± 11.1 µmol/L). Baseline citrullinemia was inversely and significantly correlated with shock index (r = -55.1%, p = 0.008) and extent of invasive ventilation support (r = -42.7%, p = 0.042). Citrullinemia < 13.7 µmol/L at admission, observed in 17.4% of patients, was associated with higher shock index (1.27 ± 0.10 versus 0.75 ± 0.18, p = 0.0001) and longer duration of invasive ventilation support (20.3 ± 7 versus 11.2 ± 7.1 days, p = 0.029) and intensive care unit stay (22 ± 5.9 versus 12.2 ± 8.8 days, p = 0.048). A citrullinemia decrease in the first day after admittance superior to 12.7% constituted a significant predictive factor of in-hospital mortality (75 versus 14.3%, p = 0.044; odds ratio = 7.8; accuracy = 65.2%; specificity = 92.3%; negative predictive value = 85.7%] and lower actuarial survival (69.8 ± 41.6 versus 278.1 ± 37.4 days, p = 0.034). CONCLUSIONS: Those results confirm the high prevalence and the prognostic relevance of hypocitrullinemia, considered a biomarker of enterocyte dysfunction, in severe trauma patients.

Identification of three novel mutations in fourteen patients with citrullinemia type 1.

OBJECTIVES: Citrullinemia type 1 (CTLN1) is an autosomal recessive genetic disorder caused by mutations in the argininosuccinate synthetase 1 (ASS1) gene, which encodes for the argininosuccinate synthetase enzyme. Here, we report genetic and clinical characterizations of 14 patients with citrullinemia type 1. DESIGN & METHODS: The study group consisted of 14 patients (4 females, 10 males) diagnosed with citrullinemia type 1 from three centers in Turkey. Age of onset, clinical presentation, initial citrulline and ammonia levels, family history and molecular genetic analysis were retrospectively evaluated. RESULTS: The mean age of the cohort and the mean age at the time of diagnosis were 48.3±36.5months (min: 12days, max: 10years) and 11.6±26.2months (min: 3days, max: 8years), respectively. In four patients, a homozygous p.Gly390Arg pathogenic variant was detected. All patients homozygous for p.Gly390Arg were diagnosed during the newborn period with the clinical presentation of classical citrullinemia. In each two patients, homozygous p.Arg86His, c.773+49C>T and p.Gly362Val pathogenic variants were detected. Clinical presentation was compatible with the mild form of the disease in patients homozygous for c.773+49C>T and for Gly362Val. Novel compound heterozygous genotypes (p.Ala164Pro/p.Gly390Arg; p.Leu290Pro/p.Gly390Arg; p.Thr389Pro/p.Gly390Arg) were identified in five patients. Of these, three siblings with CTLN1 were diagnosed with the compound heterozygous genotype p.Ala164Pro/p.Gly390Arg at the age of 4days, 5days and 2years, respectively. The other two patients with novel compound heterozygous genotypes (p.Leu290Pro/p.Gly390Arg; p.Thr389Pro/p.Gly390Arg) were identified in the first month of life as neonatal onset form and were born to non-consanguineous parents. CONCLUSION: In our study, consistent with the literature, a correlation was found between homozygous p.Gly390Arg mutation and the classic neonatal onset form. Mild citrullinemia was detected in patients with c.773+49C>T or p.Gly362Val pathogenic variants. This study adds to our understanding of the molecular genetic background of patients with CTLN1, and allows to infer on the correlation between the genotype and phenotype of the disease.

Arginine Deprivation With Pegylated Arginine Deiminase in Patients With Argininosuccinate Synthetase 1-Deficient Malignant Pleural Mesothelioma: A Randomized Clinical Trial.

IMPORTANCE: Preclinical studies show that arginine deprivation is synthetically lethal in argininosuccinate synthetase 1 (ASS1)-negative cancers, including mesothelioma. The role of the arginine-lowering agent pegylated arginine deiminase (ADI-PEG20) has not been evaluated in a randomized and biomarker-driven study among patients with cancer. OBJECTIVE: To assess the clinical impact of arginine depletion in patients with ASS1-deficient malignant pleural mesothelioma. DESIGN, SETTING, AND PARTICIPANTS: A multicenter phase 2 randomized clinical trial, the Arginine Deiminase and Mesothelioma (ADAM) study, was conducted between March 2, 2011, and May 21, 2013, at 8 academic cancer centers. Immunohistochemical screening of 201 patients (2011-2013) identified 68 with advanced ASS1-deficient malignant pleural mesothelioma. INTERVENTIONS: Randomization 2:1 to arginine deprivation (ADI-PEG20, 36.8 mg/m2, weekly intramuscular) plus best supportive care (BSC) or BSC alone. MAIN OUTCOMES AND MEASURES: The primary end point was progression-free survival (PFS) assessed by modified Response Evaluation Criteria in Solid Tumors (RECIST) (target hazard ratio, 0.60). Secondary end points were overall survival (OS), tumor response rate, safety, and quality of life, analyzed by intention to treat. We measured plasma arginine and citrulline levels, anti-ADI-PEG20 antibody titer, ASS1 methylation status, and metabolic response by 18F-fluorodeoxyglucose positron-emission tomography. RESULTS: Median (range) follow-up in 68 adults (median [range] age, 66 [48-83] years; 19% female) was 38 (2.5-39) months. The PFS hazard ratio was 0.56 (95% CI, 0.33-0.96), with a median of 3.2 months in the ADI-PEG20 group vs 2.0 months in the BSC group (P = .03) (absolute risk, 18% vs 0% at 6 months). Best response at 4 months (modified RECIST) was stable disease: 12 of 23 (52%) in the ADI-PEG20 group vs 2 of 9 (22%) in the BSC group (P = .23). The OS curves crossed, so life expectancy was used: 15.7 months in the ADI-PEG20 group vs 12.1 months in the BSC group (difference of 3.6 [95% CI, -1.0 to 8.1] months; P = .13). The incidence of symptomatic adverse events of grade at least 3 was 11 of 44 (25%) in the ADI-PEG20 group vs 4 of 24 (17%) in the BSC group (P = .43), the most common being immune related, nonfebrile neutropenia, gastrointestinal events, and fatigue. Differential ASS1 gene-body methylation correlated with ASS1 immunohistochemistry, and longer arginine deprivation correlated with improved PFS. CONCLUSIONS AND RELEVANCE: In this trial, arginine deprivation with ADI-PEG20 improved PFS in patients with ASS1-deficient mesothelioma. Targeting arginine is safe and warrants further clinical investigation in arginine-dependent cancers. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01279967.

[Value of albumin in diagnosis of neonatal intrahepatic cholestasis caused by citrin deficiency].

Objective: To investigate the clinical value of albumin (Alb) in the diagnosis of neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD). Methods: A retrospective analysis was performed for the clinical data of 90 children with NICCD who visited Children's Hospital of Fudan University from January 2007 to December 2014, and according to the content of Alb, these children were divided into Alb < 30 g/L (LA) group with 20 children and Alb ≥30 g/L (NA) group with 70 children. The clinical manifestations, results of laboratory examination, results of blood tandem mass spectrometry and urine gas chromatography-mass spectrometry, and gene detection results were compared between the two groups. The t-test and the chi-square test were used for statistical analysis.. Results: There were significant differences between the LA group and the NA group in splenomegaly degree (3.28±1.95 cm vs 1.92±1.06 cm, P = 0.030), aspartate aminotransferase/alanine aminotransferase ratio [3.15 (0.38-5.93) vs 2.14 (0.26-6.67), P = 0.010], activated partial thromboplastin time (53.27±11.68 s vs 45.06±9.79 s, P = 0.003), and international normalized ratio (1.92±1.35 vs 1.29±0.33, P = 0.001). The SLC25A13 mutation I 851_854del4 was associated with Alb (χ2 = 4.76, P = 0.025). Conclusion: As for the children with Alb < 30g/L who are highly suspected of having NICCD, SLC25A13 gene detection and blood/urine mass spectrometry should be performed as early as possible, in order to initiate intervention treatment as soon as possible, prevent and treat complications, and improve prognosis.

Anesthetic experience of an adult male with citrullinemia type II: a case report.

BACKGROUND: Citrullinemia type II is an autosomal recessive urea cycle disorder and a subtype of citrin deficiency. However, the management of recurrent hyperammonemia with neurologic symptoms in patients with citrullinemia type II is quite different from the management of other types of urea cycle disorders. In pats with citrullinemia type II, regional anesthesia might be a good choice for the early detection of hyperammonemic symptoms and addressing psychic stress. CASE PRESENTATION: A 48-year-old male with adult onset citrullinemia type II was scheduled for urethral scrotal fistula repair. During the first operation, spinal anesthesia with conscious sedation using dexmedetomidine was used, a second operation was performed after confirmation of infection control and a stable neurologic condition. In this patient, dietary planning with close monitoring of serum ammonia level and close observation of neurologic conditions might lead to successful perioperative care. CONCLUSION: For anesthesia of patients with adult onset citrullinemia type II, close monitoring of neurologic signs and serum ammonia are important to reduce neurologic complications induced by hyperammonemia. Regional anesthesia with a proper dietary plan might reduce patient stress and prevent metabolic tragedy.

Idiopathic eruptive macular pigmentation in a child with citrin deficiency.

Idiopathic eruptive macular pigmentation (IEMP) is a rare dermatological disorder with generally unclear etiology and pathogenesis. A 5½-year-old girl was referred to hospital with a 10 month history of brown skin rashes. In early infancy, citrin deficiency had been diagnosed with the SLC25A13 genotype c.851_854del4/c.998G > A, but all clinical and laboratory abnormalities recovered following the introduction of a lactose-free and medium-chain triglyceride-enriched formula. Physical examination at referral indicated symmetric, multiple and non-scaly brown macules on the neck, trunk, buttocks and proximal parts of the extremities. Histopathology indicated epidermal basal layer hyperpigmentation with an irregular distribution, along with a large number of melanophages in the upper dermis. The diagnosis of IEMP was thus made. Within 2 years of follow up, the rashes disappeared spontaneously and gradually. To our knowledge, this is the first description of IEMP in a patient with silent citrin deficiency.

Citrin deficiency presenting as acute liver failure in an eight-month-old infant.

Citrin deficiency typically presents as neonatal intrahepatic cholestasis and resolves in late infancy. Here we report a case of citrin deficiency that presented as acute liver failure in late infancy in an apparently healthy child. The full-term male infant weighed 3400 g at birth, and exhibited normal development for eight months, at which time he contracted bronchial pneumonia. The infant developed jaundice and laboratory tests indicated elevated bilirubin and ammonia levels and an abnormal coagulation profile. Plasma amino acid analysis showed elevated levels of tyrosine, methionine, citrulline, and arginine. Citrin deficiency was suspected, and genomic DNA analysis revealed a mutation (IVS16ins3kb) in SLC25A13, which encodes a mitochondrial aspartate-glutamate carrier protein. The infant was immediately put on a lactose-free, medium-chain-triglyceride-enriched formula with ursodeoxycholic acid and lipid-soluble vitamins. However, cholestasis and abnormal laboratory indices persisted, and the infant died at the age of 11.5 mo, two days before a scheduled liver transplantation. This case demonstrates that citrin deficiency can present in late infancy as acute liver failure triggered by infection, and may require liver transplantation.

First Bulgarian case of citrin deficiency caused by one novel and one recurrent mutation in the SLC25A13 gene.

Citrin deficiency is an autosomal recessive disorder caused by mutations in the SLC25A13 gene and has three phenotypes: neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) in newborns, failure to thrive and dyslipidemia caused by citrin deficiency (FTTDCD) in older children, and recurrent hyperammonemia with neuropsychiatric symptoms in citrullinemia type II (CTLN2) in adults. NICCD presents in the first few weeks of life with cholestatic hepatitis syndrome, multiple aminoacidemia and hypergalactosemia. To date almost all reported patients were from East Asia and only few cases from Caucasian origin have been described. We report the first Bulgarian case of NICCD. Mutation screening of the SLC25A13 gene revealed the compound heterozygous mutations c.1081C>T (p.R361*) and c.74C>A (p. A25E) which confirmed the diagnosis of NICCD. The nonsense mutation c.1081C>T (p.R361*) is novel.

Neonatal citrullinemia: novel, reversible neuroimaging findings correlated with ammonia level changes.

BACKGROUND: Citrullinemia type I is an autosomal recessive disorder of the urea cycle in which a patient lacks the cytosolic enzyme, argininosuccinic acid synthetase. This enzyme deficiency results in elevated levels of ammonia, glutamine, and citrulline. The accumulation of ammonia and glutamine causes neurodegenerative changes that are detectible on magnetic resonance imaging. This is the first case report of citrullinemia with repeat magnetic resonance images and electroencephalographs in the acute phase of hyperammonemia. CASE: This 3800 g white boy was born at 40 weeks 4 days gestation to a 25-year-old mother. He was delivered at home to a certified midwife with no reported complications. He was doing well until day of life 4, when the mother reported he would no longer latch to feed. He was observed to have markedly elevated ammonia levels and ultimately diagnosed with citrullinemia type I. The initial magnetic resonance image was markedly abnormal. After aggressive medical management, his repeat magnetic resonance image revealed marked improvement in the acute setting. CONCLUSION: Early and aggressive management of hyperammonemia can result in improved magnetic resonance imaging findings in the acute setting. It is too early to know if this will translate to an improved clinical outcome. Clinical suspicion must remain high for urea cycle disorders in neonates with magnetic resonance image changes similar to those resulting from hypoxic-ischemic injury.

[Characteristics of the plasma amino acid spectrum of neonatal intrahepatic cholestasis caused by citrin deficiency].

OBJECTIVE: To investigate the plasma amino acid spectrum in infants more than 1-year-old with neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) in order to identify potential diagnostic markers of NICCD. METHODS: Infants less than 1 year of age who had been referred to our hospital for investigation of suspected conjugated hyperbilirubinemia between June 2003 and June 2009 were eligible for enrollment. A total of 182 infants were enrolled and divided into three groups: infants diagnosed with NICCD (n = 24), according to gene testing and/or western blotting results; infants diagnosed with biliary atresia (BA; n = 20), according to intra-operative cholangiography findings; and infants diagnosed with idiopathic neonatal intrahepatic hepatitis (INH; n = 138), according to exclusionary findings for diseases affecting the extrahepatic biliary system and no positive serology results to indicate infections with hepatitis B, C, A or E, toxoplasmosis, rubella, herpes simplex, human immunodeficiency virus-1, or syphilis. The plasma amino acid spectrum of each infant was analyzed by tandem mass spectrometry (MS/MS). The concentrations of 18 amino acids, as well as the ratio of each amino acid to total amino acids, were compared among the three groups. Selected ratios of amino acids were analyzed by receiver operating characteristic (ROC) curve analysis. RESULTS: Compared with the BA and INH groups, the NICCD group had significantly lower levels of alanine (Ala; 175.7 and 205.7 vs. 136.3 mumol/L, P = 0.0001), aspartic acid (Asp; 47.5 and 43.1 vs. 31.55 mumol/L, P = 0.0041), glutamic acid (Glu; 276.16 and 263.24 vs. 175.71 mumol/L, P = 0.0075) and tryptophan (Trp; 41.90 and 47.97 vs. 28.51 mumol/L, P = 0.0003), but significantly higher levels of methionine (Met; 28.24 and 29.35 vs. 71.40 mumol/L, P = 0.0390), tyrosine (Tyr; 55.8 and 57.02 vs. 116.81 mumol/L, P = 0.0072) and citrulline (Cit; 15.09 and 15.65 vs. 97.42 mumol/L, P = 0.0001). The ratio of each amino acid to total amino acids showed the same trends for the NICCD group. The calculated areas under the ROC curves of the ratios of Cit, Tyr, and Met to the total amino acids were 0.874 (95% CI: 0.752 - 0.996), 0.814 (95% CI: 0.706 - 0.923), and 0.705 (95% CI: 0.535 - 0.875) respectively. The calculated area under the ROC curve of the ratio of Cit to Ala was 0.893 (95% CI: 0.781 - 1.005), and when the cut-off value of the ratio of Cit to Ala was 0.14 for diagnosis of NICCD, the sensitivity and specificity were 75% and 95% respectively. CONCLUSION: The plasma amino acid spectrum may represent a diagnostic indicator for NICCD, particularly the ratio of Cit to Ala.

Multiple ovarian antral follicles in a preterm infant with neonatal intrahepatic cholestasis caused by citrin deficiency: a clinical, genetic and transcriptional analysis.

Neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) is an autosomal recessive disease caused by the dysfunction of citrin, an aspartate/glutamate carrier encoded by the SLC25A13 gene. Considerable progress has been made on the diagnosis and treatment of NICCD, but its clinical and molecular features still remain far from being completely elucidated and generally understood. The infant, a preterm female delivered at a gestational age of 31 weeks, was referred to our hospital at the age of 8 months because of jaundice lasting for 4.5 months and ovarian masses uncovered for 3 months. Besides serum indices indicating cholestasis, elevated serum levels of luteinizing hormone, follicle stimulating hormone and estradiol were also detected. Abdominal magnetic resonance imaging demonstrated bilateral multi-cystic ovarian masses, with the largest size being 7.4 × 6.2 × 9.6 mm(3). SLC25A13 gene analysis revealed that the patient was a compound heterozygote of c.1177+1G>A and c.754G>A. The paternally-inherited mutation c.754G>A was a novel one with a carrier rate of less than 1%. SLC25A13 transcriptional study in peripheral blood lymphocytes (PBLs) documented a novel splice variant r.616_848del which resulted from c.754G>A, with another variant r.1019_1177del from the maternally-inherited c.1177+1G>A mutation. The diagnoses were NICCD and multiple ovarian antral follicles (minipuberty), and the patient responded well to a galactose-free and medium chain triglyceride (MCT)-enriched formula. The findings in this paper expanded the clinical and molecular spectrum of the SLC25A13 gene, and lent support to the concept that PBLs could be taken as a feasible specimen source for SLC25A13 transcriptional analysis.