Propionic acidemia: a neuropathology case report and review of prior cases

Propionic acidemia is a disorder of branch-chain amino acid and odd-chain fatty acid metabolism. The clinical features typically begin shortly after birth, with rare cases presenting in young adulthood. This disorder most commonly is characterized by episodic decompensations with dehydration, lethargy, nausea, and vomiting as well as a risk for neurologic sequelae. The defect is in the propionyl-CoA carboxylase enzyme with a resultant accumulation of toxic organic acid metabolites. Neuropathologic findings in this inborn error of metabolism have not been extensively characterized but include white matter spongiosis in neonates and a variable appearance in older children. We describe the pertinent literature on the neuropathology of propionic acidemia and a case report of a 4-year-old girl who had widespread gray matter vacuolization at postmortem examination. Although a previously unreported finding in propionic acidemia, diffuse gray matter vacuolization has been described in other fatty acid metabolic disorders.     

Mental health aspects of emergency medical services for children: summary of a consensus conference.

OBJECTIVE: To address the mental health needs of children involved in emergency medical services (EMS). METHODS: A multidisciplinary consensus conference convened to identify mental health needs of children and their families related to pediatric medical emergencies, to examine the impact of psychological aspects of emergencies on recovery and satisfaction with care, and to delineate research questions related to mental health aspects of medical emergencies involving children. RESULTS: The consensus group found that psychological and behavioral factors affect physical as well as emotional recovery after medical emergencies. Children's reactions are critically affected by age and developmental level, characteristics of the emergency medical event, and parent reactions. As frontline health care providers, EMS staff members are in a pivotal position to recognize and effectively manage the mental health needs of patients and their families. CONCLUSIONS: Ecological changes in emergency departments, such as linkages to mental health follow-up services, training of EMS providers and mental health professionals, and focused research that provides an empirical basis for practice, are necessary components for improving current standards of health care.     

Propionic acidemia: identification of twenty-four novel mutations in Europe and North America

Propionic acidemia is an inherited metabolic disease caused by the deficiency of the mitochondrial protein propionyl-CoA carboxylase (PCC), one of the four biotin-dependent enzymes. PCC is a multimeric protein composed of two different alpha- and beta-PCC subunits, nuclearly encoded by the PCCA and PCCB genes, respectively. Mutations in either gene cause the clinically heterogeneous disease propionic acidemia. In this work we describe the mutational analysis of PCCA and PCCB deficient patients from different European countries (Spain, Italy, Belgium, Croatia, and Austria) and from America (mainly USA). We report 24 novel PA mutations, nine affecting the PCCA gene and 15 affecting the PCCB gene. They include six missense mutations, one nonsense mutation, one point exonic mutation affecting splicing, seven splicing mutations affecting splice sequences, and nine short insertions or deletions, only two in-frame. We have found a highly heterogenous spectrum of PCCA mutations, most of the PCCA deficient patients are homozygous carrying a unique genotype. The PCCA mutational spectrum includes a high proportion of short insertions or deletions affecting one nucleotide. In the PCCA mutant alleles analyzed we have also found one single nucleotide change, a novel nonsynonymous SNP. On the other hand, the PCCB deficient patients carry a more reduced spectrum of mutations, 50% of them are missense. This work represents an extensive update of the mutational study of propionic acidemia providing important information about the worldwide distribution of PA mutations and representing another essential part in the study of the phenotype-genotype correlations for the prediction of the metabolic outcome and for the implementation of treatments tailored to each PA patient.     

Propionic acidemia: analysis of mutant propionyl-CoA carboxylase enzymes expressed in Escherichia coli

Deficiency of propionyl-CoA carboxylase (PCC) results in propionic acidemia, an autosomal recessive disorder characterized by ketoacidosis sufficiently severe to cause neonatal death. PCC is involved in the catabolism of branched-chain amino acids, odd-chain fatty acids, and cholesterol. The enzyme is a biotin-dependent mitochondrial protein composed of two heterologous subunits arranged into an 800-kDa alpha(6 )beta(6) dodecameric structure. Approximately 60 mutations have been reported in the nuclear genes PCCA and PCCB that encode the two PCC subunits. The vast majority of these mutations have not been examined at the protein level. We present an initial characterization of 13 mutations located in exons 1, 3-7, and 12-14 of PCCB. After expression in E. coli, these recombinant mutant enzymes were analyzed for stability, biotinylation, alpha-beta subunit interaction, and activity. Our results show a functional dichotomy in these PCCB mutations with some mutants (R44P, S106R, G131R, G198D, V205D, I408del, and M442T) capable of varying degrees of assembly but forming catalytically inactive PCC proteins. Other PCCB mutants (R165W, E168K, D178H, P228L, and R410W) that are PCC deficient in patient-derived fibroblasts, were found to be capable of expressing wild-type level PCC activity when assembled in our chaperone-assisted E. coli expression system. This result indicates that these mutations exert their pathogenic effect due to an inability to assemble correctly in patients' cells. This initial screen has identified a range of mutant PCC proteins that are sufficiently stable to be purified and subsequently used for structure-function analysis to further elucidate the complex relationship between genotype and phenotype in propionic acidemia.     

Evaluation of mental retardation: Recommendations of a consensus conference

A Consensus Conference utilizing available literature and expert opinion sponsored by the American College of Medical Genetics in October 1995 evaluated the rational approach to the individual with mental retardation. Although no uniform protocol replaces individual clinician judgement, the consensus recommendations were as follows: 1. The individual with mental retardation, the family, and medical care providers benefit from a focused clinical and laboratory evaluation aimed at establishing causation and in providing counseling, prognosis, recurrence risks, and guidelines for management. 2. Essential elements of the evaluation include a three-generation pedigree: pre-, peri-, and post-natal history, complete physical examination focused on the presence of minor anomalies, neurologic examination, and assessment of the behavioral phenotype. 3. Selective laboratory testing should, in most patients, include a banded karyotype. Fragile X testing should be strongly considered in both males and females with unexplained mental retardation, especially in the presence of a positive family history, a consistent physical and behavioral phenotype and absence of major structural abnormalities. Metabolic testing should be initialed in the presence of suggestive clinical and physical findings. Neuroimaging should be considered in patients without a known diagnosis especially in the presence of neurologic symptoms, cranial contour abnormalities, microcephaly, or macrocephaly. In most situations MRI is the testing modality of choice. 4. Sequential evaluation of the patient, occasionally over several years, is often necessary for diagnosis, allowing for delineation of the physical and behavioral phenotype, a logical approach to ancillary testing and appropriate prognostic and reproductive counseling. Am. J. Med. Genet. 72:468–477, 1997. © 1997 Wiley-Liss, Inc.     

Asthma and the elite athlete: summary of the International Olympic Committee's consensus conference, Lausanne, Switzerland, January 22-24, 2008

Respiratory symptoms cannot be relied on to make a diagnosis of asthma and/or airways hyperresponsiveness (AHR) in elite athletes. For this reason, the diagnosis should be confirmed with bronchial provocation tests. Asthma management in elite athletes should follow established treatment guidelines (eg, Global Initiative for Asthma) and should include education, an individually tailored treatment plan, minimization of aggravating environmental factors, and appropriate drug therapy that must meet the requirements of the World Anti-Doping Agency. Asthma control can usually be achieved with inhaled corticosteroids and inhaled beta(2)-agonists to minimize exercise-induced bronchoconstriction and to treat intermittent symptoms. The rapid development of tachyphylaxis to beta(2)-agonists after regular daily use poses a dilemma for athletes. Long-term intense endurance training, particularly in unfavorable environmental conditions, appears to be associated with an increased risk of developing asthma and AHR in elite athletes. Globally, the prevalence of asthma, exercise-induced bronchoconstriction, and AHR in Olympic athletes reflects the known prevalence of asthma symptoms in each country. The policy of requiring Olympic athletes to demonstrate the presence of asthma, exercise-induced bronchoconstriction, or AHR to be approved to inhale beta(2)-agonists will continue.     

Physician manpower for rural America: summary of a WAMI region conference

Although legislators have intermittently focused their attention on physician manpower issues, the needs of rural America for physicians remain unmet. These needs will not be met unless there is an adequate supply of physicians receptive to and appropriately trained for the challenges and opportunities of practice in a rural community. A declining interest by matriculating and graduating medical students in primary care practice makes it problematic that the needs of rural America can be met in the near future unless medical schools attempt to reverse the trends in medical students' specialty choices. In October 1989, the University of Washington School of Medicine conducted a working conference on physician manpower issues facing rural communities in Washington, Alaska, Montana, and Idaho. The discussions and conclusions of this conference about increasing the percentage of graduates entering rural practice apply to other regions of the country, and this paper summarizes the conference's recommendations.     

Directions and needs in asbestos research: new insights: conference summary

The Center for Environmental Health Sciences (CEHS) Conference, entitled "Directions and Needs in Asbestos Research: New Insights," was held at the University of Montana in Missoula. Researchers, physicians, health care workers, and federal agency representatives from around the country met for a cross-disciplinary exploration of many issues related to asbestos research. Topics included community and psychosocial issues in biomedical research, asbestos exposure assessment, assessment and mechanisms of asbestos related diseases, and new research directions. This meeting report is a summary of the conference presentations, and of the topics identified for future research directions. This conference was a follow-up to one hosted by the CEHS in June 2002, and continued to take advantage of opportunities to work with a unique population in Libby MT, where significant asbestos exposures have occurred due to the mining of asbestos-contaminated vermiculite. The goals of this conference were to bring together experts from diverse fields to identify progress made since the last conference and to develop new research avenues that would allow us to address the research needs in emerging asbestos-exposed populations. Participants indicated that these objectives were met, and expressed enthusiasm for follow-up conferences to maintain the dialog that has been established regarding directions and needs in asbestos research. Selected papers from the conference are presented here.     

EURECCA consensus conference highlights about colorectal cancer clinical management: the pathologists expert review

Care for patients with colon and rectal cancer has improved in the last 20 years; however, a considerable variation still exists in cancer management and outcome between European countries. Large variation is also apparent between national guidelines and patterns of cancer care in Europe. Therefore, EURECCA, which is the acronym of European Registration of Cancer Care, is aiming at defining core treatment strategies and developing a European audit structure in order to improve the quality of care for all patients with colon and rectal cancer. In December 2012, the first multidisciplinary consensus conference about cancer of the colon and rectum was held. The expert panel consisted of representatives of European scientific organizations involved in cancer care of patients with colon and rectal cancer and representatives of national colorectal registries.     

Beyond consensus: a summary of the special series and future of the Combined-Integrated model

The articles that comprise this Special Series offer a comprehensive examination of the results and implications of the Consensus Conference and Combined-Integrated (C-I) model of doctoral training in professional psychology (see Shealy, Cobb, Crowley, Nelson, & Peterson, 2004). Given the scope of this effort, it may be helpful to provide a summary of the 12 preceding articles. Such a presentation should illustrate the complementarity of the diverse perspectives presented in this series, the essential coherence of this innovative and compelling model of education and training, and its timely relevance for the future of professional psychology. Following a summary of these articles, eight "future topics for discussion" also are presented.     

Priorities for antiretroviral therapy research in sub-Saharan Africa: a 2002 consensus conference in Zambia

BACKGROUND: A consensus conference was held to discuss priorities for antiretroviral therapy (ART) research in Zambia, one of the world's most heavily HIV-afflicted nations. Zambia, like other resource-limited settings, has increasing access to highly active antiretroviral therapy (HAART) because of declining drug costs, use of government-purchased generic medications, and increased global donations. For sustained delivery of care with HAART in a resource-constrained medical and public health context, operational research is required and clinical trials are desirable. The priority areas for research are most relevant today given the increasing availability of HAART. METHODS: A conference was held in Lusaka, Zambia, in January 2002 to discuss priority areas for ART research in Zambia, with participants drawn from a broad cross section of Zambian society. State-of-the-art reviews and 6 intensive small group discussions helped to formulate a suggested research agenda. RESULTS: Conference participants believed that the most urgent research priorities were to assess how therapeutic resources could be applied for the greatest overall benefit and to minimize the impact of nonadherence and viral resistance. Identified research priorities were as follows:Conference participants recommended that HIV-related clinical care and research be integrated within home-based care services and operated within the existing health delivery structures to ensure sustainability, reduce costs, and strengthen the structures. CONCLUSION: Our consensus was that antiretroviral clinical trials and operational research are essential for Zambia to address the new challenges arising from increasing ART availability. There is global consensus that antiretroviral clinical trials in resource-constrained countries are possible, and the capacity for such trials should be developed further in Africa.     

International society of urological pathology consensus conference on handling and staging of radical prostatectomy specimens

The 2009 International Society of Urological Pathology consensus conference on handling and staging of radical prostatectomy specimens issued recommendations for standardization of pathology reporting of radical prostatectomy specimens. The conference addressed specimen handling, T2 substaging, prostate cancer volume, extraprostatic extension, lymphovascular invasion, seminal vesicle invasion, lymph node metastases, and surgical margins. This review summarizes the conclusions and recommendations resulting from the consensus process.     

Glutaric acidemia type 1

Glutaric acidemias comprise different disorders resulting in an increased urinary excretion of glutaric acid. Glutaric acidemia type 1 (GA-1) is an autosomal recessive disorder of lysine, hydroxylysine, and tryptophan metabolism caused by deficiency of glutaryl-CoA dehydrogenase. It results in the accumulation of 3-hydroxyglutaric and glutaric acid. Affected patients can present with brain atrophy and macrocephaly and with acute dystonia secondary to striatal degeneration in most cases triggered by an intercurrent childhood infection with fever between 6 and 18 months of age. This disorder can be identified by increased glutaryl (C5DC) carnitine on newborn screening. Urine organic acid analysis indicates the presence of excess 3-OH-glutaric acid, and urine acylcarnitine profile shows glutaryl carnitine as the major peak. Therapy consists in carnitine supplementation to remove glutaric acid, a diet restricted in amino acids capable of producing glutaric acid, and prompt treatment of intercurrent illnesses. Early diagnosis and therapy reduce the risk of acute dystonia in patients with GA-1.     

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.     

Hyperpipecolic acidemia in neonatal adrenoleukodystrophy

Serum pipecolic acid was measured in patients with neonatal adrenoleukodystrophy (NALD), sex-linked ALD, and the cerebrohepatorenal syndrome of Zellweger. Pipecolic acid was elevated, often markedly, in most of the patients with NALD but in none of those with X-linked ALD or adrenomyeloneuropathy, or in normal adults and children, or children with cirrhosis or other neurodegenerative disorders. The demonstration of elevated serum pipecolic acid in NALD adds to the previously recognized elevation of very-long-chain fatty acids (another Zellweger syndrome sign) and suggests that generalized peroxisomal dysfunction may be a characteristic of NALD as it appears to be of Zellweger syndrome, which diseases share some clinical characteristics. The nosologic significance of these findings is discussed.