Case reports of successful pregnancy in women with maple syrup urine disease and propionic acidemia.

We report on 2 women with organic acidemias, one with classical maple syrup urine disease and another with mild propionic acidemia in which protein restricted diets and carnitine supplementation were successfully employed to manage pregnancies. Healthy infants were delivered without maternal metabolic decompensation.     

Adenoviral-mediated correction of methylmalonyl-CoA mutase deficiency in murine fibroblasts and human hepatocytes

Background  

Methylmalonic acidemia (MMA), a common organic aciduria, is caused by deficiency of the mitochondrial localized, 5'deoxyadenosylcobalamin dependent enzyme, methylmalonyl-CoA mutase (MUT). Liver transplantation in the absence of gross hepatic dysfunction provides supportive therapy and metabolic stability in severely affected patients, which invites the concept of using cell and gene delivery as future treatments for this condition.     

Elevated methylmalonic acidemia (MMA) screening markers in Hispanic and preterm newborns

Analysis of California newborn screening (NBS) data revealed a high prevalence of Hispanic infants testing positive for methylmalonic acidemia (MMA), a trend seen for both true- and false-positive cases. Here we show that Hispanic infants have significantly higher levels of MMA screening markers than non-Hispanics. Preterm birth and increased birth weight were found to be associated with elevated MMA marker levels but could not entirely explain these differences. While the preterm birth rate was higher in Blacks than Hispanics, Black infants had on average the lowest MMA marker levels. Preterm birth was associated with lower birth weight and increased MMA marker levels suggesting that gestational age is the stronger predictive covariate compared to birth weight. These findings could help explain why MMA false-positive results are more likely in Hispanic than in Black infants, which could inform screening and diagnostic procedures for MMA and potentially other disorders in newborns.     

Case reports of successful pregnancy in women with maple syrup urine disease and propionic acidemia

We report on 2 women with organic acidemias, one with classical maple syrup urine disease and another with mild propionic acidemia in which protein restricted diets and carnitine supplementation were successfully employed to manage pregnancies. Healthy infants were delivered without maternal metabolic decompensation. © 1992 Wiley-Liss, Inc.     

Combining newborn metabolic and DNA analysis for second-tier testing of methylmalonic acidemia

PurposeImproved second-tier tools are needed to reduce false-positive outcomes in newborn screening (NBS) for inborn metabolic disorders on the Recommended Universal Screening Panel (RUSP).MethodsWe designed an assay for multiplex sequencing of 72 metabolic genes (RUSPseq) from newborn dried blood spots. Analytical and clinical performance was evaluated in 60 screen-positive newborns for methylmalonic acidemia (MMA) reported by the California Department of Public Health NBS program. Additionally, we trained a Random Forest machine learning classifier on NBS data to improve prediction of true and false-positive MMA cases.ResultsOf 28 MMA patients sequenced, we found two pathogenic or likely pathogenic (P/LP) variants in a MMA-related gene in 24 patients, and one pathogenic variant and a variant of unknown significance (VUS) in 1 patient. No such variant combinations were detected in MMA false positives and healthy controls. Random Forest–based analysis of the entire NBS metabolic profile correctly identified the MMA patients and reduced MMA false-positive cases by 51%. MMA screen-positive newborns were more likely of Hispanic ethnicity.ConclusionOur two-pronged approach reduced false positives by half and provided a reportable molecular finding for 89% of MMA patients. Challenges remain in newborn metabolic screening and DNA variant interpretation in diverse multiethnic populations.     

Methylmalonic and propionic aciduria

Methylmalonic and propionic aciduria (PA) are the most frequent forms of branched-chain organic acidurias. These autosomal recessive disorders result from deficient activity of methylmalonyl-CoA mutase and propionyl-CoA carboxylase, respectively. Clinically, acute or chronic neurologic signs are caused by the accumulation of toxic compounds proximal to the metabolic block. Phenotype varies from severe neonatal-onset forms with high mortality and poor outcome to milder forms with a later onset. In both cases the clinical course is dominated by the risk of relapses of life-threatening episodes of metabolic decompensation and of severe organ failure. Despite improvement of treatment, the overall outcome remains disappointing with no major differences between the two diseases. The diagnosis is based on the presence of characteristic compounds in body fluids as detected by organic acid analysis in urine and acylcarnitine profile in blood. Therapy is based on low-protein high-energy diet, carnitine supplementation, and metronidazole. Some patients with methylmalonic aciduria (MMA) respond to pharmacological doses of vitamin B12. Given the poor long-term prognosis, liver transplantation has been recently attempted as an alternative therapy to conventional medical treatment to cure the underlying metabolic defect. Nevertheless, the overall experience to date does not clearly demonstrate its effectiveness in preventing further deterioration or improving survival and quality of life. The recent implementation of neonatal screening by electrospray tandem mass spectrometry has decreased early mortality and improved the short-term outcome, without changing the detection rate of both diseases in the screening population compared to clinically detected cases. However, the limited number of patients and the short duration of their follow-up do not yet permit drawing final conclusions on its effect on the long-term outcome of methylmalonic and propionic acidemia.     

大鼠内毒素性和败血症性休克时某些血中代谢物变化的探讨

内毒素性和败血症性休克都有高乳酸和高氮质血症。不同的是，前者在注射内毒素后３０ｍｉｎ／血糖和动脉血压同步地进行性下降，血胰岛素水平不变，后者血糖轻度升高，血胰岛素水平降低。预先应用山莨菪硷后两型休克的高乳酸症均被有效预防，血糖变化被调整，但对高氮质血症却无影响，因为含氮物的升高是由于早期肾血管收缩所致。山莨菪硷虽能保护细胞并可因此而改善微循环，但却不能消除低动力型氧供不足，表明代谢变化不是乏氧可用     

Neurologic considerations in propionic acidemia

Propionic acidemia (PA) is an organic acidemia which has a broad range of neurological complications, including developmental delay, intellectual disability, structural abnormalities, metabolic stroke-like episodes, seizures, optic neuropathy, and cranial nerve abnormalities. As the PA consensus conference hosted by Children's National Medical Center progressed from January 28 to 30, 2011, it became evident that neurological complications were common and a major component of morbidity, but the role of imaging and the basis for brain pathophysiology were unclear. This paper reviews the hypothesized pathophysiology, presentation and uses the best available evidence to suggest programs for treatment, imaging, and monitoring the neurological complications of PA.     

Furosemide is associated with acute kidney injury in critically ill patients

Acute kidney injury (AKI) is common in critically ill patients. Diuretics are used without any evidence demonstrating a beneficial effect on renal function. The objective of the present study is to determine the incidence of AKI in an intensive care unit (ICU) and if there is an association between the use of furosemide and the development of AKI. The study involved a hospital cohort in which 344 patients were consecutively enrolled from January 2010 to January 2011. A total of 132 patients (75 females and 57 males, average age 64 years) remained for analysis. Most exclusions were related to ICU discharge in the first 24 h. Laboratory, sociodemographic and clinical data were collected until the development of AKI, medical discharge or patient death. The incidence of AKI was 55% (95%CI = 46-64). The predictors of AKI found by univariate analysis were septic shock: OR = 3.12, 95%CI = 1.36-7.14; use of furosemide: OR = 3.27, 95%CI = 1.57-6.80, and age: OR = 1.02, 95%CI = 1.00-1.04. Analysis of the subgroup of patients with septic shock showed that the odds ratio of furosemide was 5.5 (95%CI = 1.16-26.02) for development of AKI. Age, use of furosemide, and septic shock were predictors of AKI in critically ill patients. Use of furosemide in the subgroup of patients with sepsis/septic shock increased (68.4%) the chance of development of AKI when compared to the sample as a whole (43.9%)     

Screening for methylmalonic aciduria in Alberta: a voluntary program with particular significance for the Hutterite Brethren

A selective, voluntary urine screening program has been established to facilitate detection and early treatment of infants with methylmalonic acidurias (MMA), a group of rare, potentially lethal, autosomal recessive disorders of organic acid metabolism. The laboratory methods have been modified for newborn infants so that urine specimens can be collected on filter paper in the diaper and tested by the thin-layer chromatography method. One Hutterite child was previously known to have methylmalonyl-coenzyme A (MMCoA) mutase deficiency (mut0) which is unresponsive to vitamin B12 but is responsive to diet and other therapeutic measures. No undiagnosed existing cases of MMA were identified by the voluntary screening program among 1,165 Hutterite infants and preschool children.     

Extracorporeal membrane oxygenation support of a severe metabolic crisis in a child with methylmalonic acidemia

A 9-year-old female, with mut phenotype of methylmalonic acidemia who developed severe vasoplegic shock during a metabolic crisis, was successfully supported with venoarterial extracorporeal membrane oxygenation.     

Glutaric acidemia type II. Comparison of pathologic features in two infants

Glutaric acidemia type II (GA II) is a metabolic disorder caused by deficiency of electron transport flavoprotein or its oxyreductase. It is characterized by acidosis, hypoglycemia, hyperammonemia, organic aciduria, and "sweat-sock" odor. Neonatal GA II differs from most inborn metabolic errors in that there are prominent congenital malformations. We recently observed two infants at autopsy with GA II whose malformations included: subcortical renal glomerular cysts, renal medullary dysplasia, cerebral pachygyria, pulmonary hypoplasia, and facial dysmorphism. In addition, there was lipid accumulation in liver, heart, and renal tubular epithelium, tissues that use fatty acids as a primary source of energy. Review of previous reports of 12 patients showed that these lesions are typical of neonatal GA II. The pattern of lesions, in particular the striking localization of renal dysplasia to the medulla, suggests that the malformations may be the consequence of an accumulation of toxic metabolites that is not corrected by placental transfer.     

Long-term liver disease in methylmalonic and propionic acidemias

Background and objectives

Patients affected with methylmalonic acidemia (MMA) and propionic acidemia (PA) exhibit diverse long-term complications and poor outcome. Liver disease is not a reported complication. The aim of this study was to characterize and extensively evaluate long-term liver involvement in MMA and PA patients.

Severe adenovirus pneumonia in immunocompetent adults: a case report and review of the literature

Adenovirus is a frequent cause of mild self-limiting upper respiratory tract infection, gastroenteritis, and conjunctivitis in infants and young children. Fatal infections (severe pneumonia progressing to respiratory failure, septic shock and/or encephalitis) are rare among immunocompetent adults. We report a case of severe adenovirus pneumonia in a young immunocompetent male who presented with sudden onset respiratory distress that progressed rapidly to respiratory failure and made a successful recovery on supportive measures. Systematic review of the literature identified 14 cases of severe adenovirus pneumonia (defined as respiratory failure requiring ventilatory support at any point during the course of illness) in otherwise healthy immunocompetent adults both in epidemic and community settings. We describe the clinical characteristics, radiological features, and outcome of identified cases.     

感染性和内毒素性休克大鼠动脉组织中硫化氢的变化

探讨内源性硫化氢 (H2 S)在感染性和内毒素性休克大鼠血管组织中的含量变化及意义。用盲肠结扎穿孔法制备大鼠感染性休克模型和静脉注射内毒素法制备内毒素休克大鼠模型 ,观察大鼠血液动力学、代谢变化及测定内源性硫化氢含量和一氧化氮含量 ,并计算其相关性。感染性及内毒素性休克大鼠的血液动力学参数均明显低于对照组 ,而左室舒张末压明显高于对照组 (P <0 0 1) ,血糖明显低于对照组 (P <0 0 1) ,血乳酸水平明显高于对照组(P <0 0 1)。感染性和内毒素性休克大鼠动脉组织中H2 S含量明显高于对照组 ,(均P <0 0 1)。休克大鼠血管H2 S含量与血压、心功能及低血糖的程度呈高度负相关 (均P <0 0 1)。以上结果说明内源性H2 S可能参与休克过程中的病理生理调节     

Natural history of propionic acidemia

Propionic acidemia is an organic acidemia that can lead to metabolic acidosis, coma and death, if not treated appropriately in the acute setting. Recent advancements in treatment have allowed patients with propionic acidemia to live beyond the neonatal period and acute presentation. The natural history of the disease is just beginning to be elucidated as individuals reach older ages. Recent studies have identified the genomic mutations in the genes PCCA and PCCB. However, as of yet no clear genotype-phenotype correlations are known. As patients age, the natural progression of propionic acidemia illuminates intellectual difficulties, increased risk for neurological complications, including stroke-like episodes, cardiac complications, and gastrointestinal difficulties, as well as a number of other complications. This article reviews the available literature for the natural history of propionic acidemia.     

Pharmacologic amino acid acylation in the acute hyperammonemia of propionic acidemia

An infant with propionic acidemia presented at one month of age with hyperammonemic coma. Treatment by two double-volume exchange transfusions did not have an appreciable effect, but hemodialysis led to a substantial reduction of the serum concentration of ammonia on two occasions. Nevertheless, continued therapy with sodium benzoate, arginine-HCl, carnitine and lactulose did not have any observable effect on the blood concentration of ammonia. Treatment with sodium phenylacetate was followed by a reduction in serum concentrations of ammonia to normal levels which were maintained. These observations demonstrate the dramatic reduction in serum concentrations of ammonia that may be obtained in patients with organic acidemia by hemodialysis. They suggest that pharmacologic acylation therapy with phenylacetate may be of lasting benefit in the management of this complication.     

Genetic and genomic systems to study methylmalonic acidemia

Methylmalonic acidemia (MMAemia) is the biochemical hallmark of a group of genetic metabolic disorders that share a common defect in the ability to convert methylmalonyl-CoA into succinyl-CoA. This disorder is due to either a mutant methylmalonyl-CoA mutase apoenzyme or impaired synthesis of adenosylcobalamin, the cofactor for this enzyme. In this article, we will provide an overview of the pathways disrupted in these disorders, discuss the known metabolic blocks with a particular focus on molecular genetics, and review the use of selected model organisms to study features of methylmalonic acidemia.     

Extracellular heat shock protein 60 (Hsp60) levels in children with septic shock

Objective and design: Recent data suggest that extracellular Hsp60 modulates the host innate immune response. We analyzed plasma Hsp60 levels in children admitted to a level III tertiary care PICU with septic shock. Materials and subjects: Blood samples were obtained from children meeting criteria for septic shock (n = 63), critically ill children without septic shock (n = 10), and healthy controls (n = 24). Treatment: Not applicable. Methods: Hsp60 levels were measured in the plasma using a commercially available ELISA. Differences between groups were analyzed with a Kruskal-Wallis one way ANOVA due to the non-parametric nature of the data. A p value ≤ 0.05 was considered significant. Results: Extracellular Hsp60 levels were significantly higher in children with septic shock (median, 16.7 ng/mL) compared to both critically ill children without septic shock (median, 0 ng/mL) and healthy controls (median, 0 ng/mL, p <0.001). Conclusions: Extracellular Hsp60 levels are significantly elevated in children with septic shock compared with both healthy controls and critically ill children without sepsis. Extracellular Hsp60 may play a role in the pathogenesis of sepsis in children. Received 3 July 2006; returned for revision 18 October 2006; accepted by K. Visvanathan 6 December 2006