Propionic acidemia: neonatal versus selective metabolic screening

BACKGROUND

Whereas propionic acidemia (PA) is a target disease of newborn screening (NBS) in many countries, it is not in others. Data on the benefit of NBS for PA are sparse.

STUDY DESIGN

Twenty PA patients diagnosed through NBS were compared to 35 patients diagnosed by selective metabolic screening (SMS) prompted by clinical findings, family history, or routine laboratory test results. Clinical and biochemical data of patients from 16 metabolic centers in Germany, Austria, and Switzerland were evaluated retrospectively. Additionally, assessment of the intelligent quotient (IQ) was performed. In a second step, the number of PA patients who have died within the past 20 years was estimated based on information provided by the participating metabolic centers.

RESULTS

Patients diagnosed through NBS had neither a milder clinical course regarding the number of metabolic crises nor a better neurological outcome. Among NBS patients, 63% were already symptomatic at the time of diagnosis, and <10% of all patients remained asymptomatic. Among all PA patients, 76% were found to be at least mildly mentally retarded, with an IQ <69. IQ was negatively correlated with the number of metabolic decompensations, but not simply with the patients' age. Physical development was also impaired in the majority of patients. Mortality rates tended to be lower in NBS patients compared with patients diagnosed by SMS.

CONCLUSION

Early diagnosis of PA through NBS seems to be associated with a lower mortality rate. However, no significant benefit could be shown for surviving patients with regard to their clinical course, including the number of metabolic crises, physical and neurocognitive development, and long-term complications.

Mutation analysis in 54 propionic acidemia patients

Deficiency of propionyl CoA carboxylase (PCC), a dodecamer of alpha and beta subunits, causes inherited propionic acidemia. We have studied, at the molecular level, PCC in 54 patients from 48 families comprised of 96 independent alleles. These patients of various ethnic backgrounds came from research centers and hospitals in Germany, Austria and Switzerland. The thorough clinical characterization of these patients was described in the accompanying paper (Grünert et al. 2012). In all 54 patients, many of whom originated from consanguineous families, the entire PCCB gene was examined by genomic DNA sequencing and in 39 individuals the PCCA gene was also studied. In three patients we found mutations in both PCC genes. In addition, in many patients RT-PCR analysis of lymphoblast RNA, lymphoblast enzyme assays, and expression of new mutations in E.coli were carried out. Eight new and eight previously detected mutations were identified in the PCCA gene while 15 new and 13 previously detected mutations were found in the PCCB gene. One missense mutation, p.V288I in the PCCB gene, when expressed in E.coli, yielded 134% of control activity and was consequently classified as a polymorphism in the coding region. Numerous new intronic polymorphisms in both PCC genes were identified. This study adds a considerable amount of new molecular data to the studies of this disease.

STATISTICAL INFORMATION CHARACTERIZATION OF CONSERVED NON-CODING ELEMENTS IN VERTEBRATES

Recently, a set of highly conserved non-coding elements (CNEs) has been derived from a comparison between the genomes of the puffer fish, Takifugu or Fugu rubripes, and man. In order to facilitate the identification of these conserved elements in silico, we characterize them by a number of statistical features.

We found a pronounced information pattern around CNE borders; although the CNEs themselves are AT rich and have high entropy (complexity), they are flanked by GC-rich regions of low entropy (complexity). We also identified the most abundant motifs within and around of CNEs, and identified those that group around their borders. Like in human promoter regions, the TBP, NF-Y and some other binding motifs are clustered around CNE boundaries, which may suggest a possible transcription regulatory function of CNEs.

Tumour epithelial vimentin expression and outcome of pancreatic ductal adenocarcinomas

PURPOSE

Tumour epithelial vimentin expression is a marker of mesenchymal differentiation and may be a useful marker of carcinomas with more aggressive behaviour. The aim of this study was to determine the extent and prognostic significance of vimentin expression in pancreatic ductal adenocarcinomas.

METHODS

Vimentin expression was detected by immunohistochemistry on tissue microarrays of surgically resected pancreatic ductal adenocarcinomas from 387 patients. The percentage of vimentin-immunolabelled neoplastic cells was correlated with outcome and with clinico-pathological factors using the Kaplan-Meier method and Cox multivariate survival models.

RESULTS

In all, 45% of primary pancreatic adenocarcinomas contained neoplastic cells that expressed vimentin, and in 27.5% of the cancers >10% of cells expressed vimentin. Vimentin expression was correlated with poor histological differentiation. By both uni- and multivariate survival analysis, neoplastic vimentin expression (P<0.01, HR 1.52, 95% confidence interval 1.14-2.04) was an indicator of a shorter postsurgical survival independent of other clinico-pathological variables.

CONCLUSION

The presence of vimentin-expressing tumour epithelial cells in surgically resected pancreatic adenocarcinomas independently predicted a shorter postsurgical survival.

Balloon valvuloplasty in the treatment of congenital aortic valve stenosis--a retrospective multicenter survey of more than 1000 patients

BACKGROUND

The value of balloon valvuloplasty of the aortic valve in childhood is still under debate.

OBJECTIVE

To evaluate the results of the procedure in a retrospective multicenter survey of a large cohort over a long time interval.

METHODS

Retrospective analysis of 1004 patients with balloon valvuloplasty of the aortic valve performed between 9/1985 and 10/2006 at 20 centers in Germany, Austria and Switzerland. Amongst others, the following parameters were evaluated before and after the procedure as well as at the end of follow-up or before surgery: clinical status, left ventricular function, transaortic pressure gradient, degree of aortic regurgitation, freedom from re-intervention or surgery.

PATIENTS

Patients from 1 day to 18 years of age with aortic valve stenosis were divided into four groups: 334 newborns (1-28 days); 249 infants (29-365 days); 211 children (1-10 years), and 210 adolescents (10-18 years).

RESULTS

Median follow-up was 32 months (0 days to 17.5 years). After dilatation the pressure gradient decreased from 65 (± 24)mm Hg to 26 (± 16)mm Hg and remained stable during follow-up. The newborns were the most affected patients. Approximately 60% of them had clinical symptoms and impaired left ventricular function before intervention. Complication rate was 15% in newborns, 11% in infants and 6% in older children. Independently of age, 50% of all patients were free from surgery 10 years after intervention.

CONCLUSIONS

In this retrospective multicenter study, balloon valvuloplasty of the aortic valve has effectively postponed the need for surgery in infants, children and adolescents up to 18 years of age.

Imaging findings in a 3-year-old girl with type III pleuropulmonary blastoma

Pleuropulmonary blastoma (PPB) is a rare dysembryonic intrathoracic neoplasm in children. It is a malignant tumour originating from the mesenchyme with a poor prognosis. We report on a 3-year-old girl who presented with respiratory symptoms and was diagnosed as having a type III PPB according to histological results attained by open biopsy. Imaging by CT and MRI revealed the exact size of the tumour involving the left lower lobe with displacement of the mediastinum and the diaphragm. Additional FDG-PET was important to evaluate tumour vitality and to decide the time of surgery, which was performed after 12 weeks of chemotherapy with the CWS2002P protocol. After R0 resection without complications and postoperative chemotherapy, the child continues to be in complete remission. This case underlines the importance of radical surgery of the aggressive neoplasm in combination with chemotherapy and the usefulness of multimodal imaging for the optimal planning of local therapy.

[Fabry disease: demographic data since introduction of enzyme replacement therapy]

BACKGROUND AND OBJECTIVE

Fabry's disease is a rare, X-chromosome linked recessive lysosomal storage disorder. In its course multiple organ damage occurs, e.g. in skin, nerves, kidneys and heart. The disease not only markedly impairs the quality of life but also shortens life expectancy if untreated. As it is a rare and not widely known disease with considerable variability of its symptoms it is often not or only belatedly diagnosed. Since 2001, enzyme replacement has become available as an option in the causal treatment. It was the aim of this study to analyse the demography and clinical expression of the disease.

PATIENTS AND METHODS

Data were obtained from the Fabry Outcome Survey (FOS), a Europe-wide data bank for the documentation of the disease's clinical course, on 262 patients (130 males, 132 females; mean age 37.5 and 34 years, respectively on entry in the FOS) in Germany, Switzerland and Austria.

RESULTS

Typical symptoms - acroparesthesias, joint pain, hypohidrosis, fever and angiokeratoma - have their onset in childhood (mean age nine years). Symptoms start significantly earlier in males than females. The interval between onset of the first symptoms and establishment of the diagnosis is about 15 years. The severity of the clinical picture, as measured in the POS Mainz severity score index (MSSI), correlates significantly with the person's age (p = 0.0001). Main causes of morbidity and death in Fabry's disease are involvement of the kidneys or heart, the one or other occurring in 75% of patients. 171 patients (38 [65.3%]: 92 males, 79 females) are at present being continually treated with enzyme-replacement (ERT), agalsidase-a, i.e. 70.8% of all male and 59.8 of all female patients in the FOS.

CONCLUSIONS

It is of great importance for the prognosis and quality that Fabry's disease is diagnosed as early as possible and treated adequately before the onset of organ damage. If the listed symptoms by themselves remain unexplained, Fabry's disease should be considered in the differential diagnosis. National and international observational studies, such as the FOS, significantly contribute to gaining important clinical data on this heterogeneous disease.

Non-invasive assessment of tumor proliferation using triple quantum filtered 23/Na MRI: technical challenges and solutions

We address the development of triple-quantum-filtered sodium MRI as a non-invasive surrogate measure for cell proliferation in brain tumors. We demonstrate that through careful consideration of the theoretical description of the signal, triple-quantum-filtered sodium images of adequate signal-to-noise ratio (SNR) can be acquired in clinically acceptable imaging times.