Dataset Information

Selective screening for lysosomal storage diseases with dried blood spots collected on filter paper in 4,700 high-risk colombian subjects.

ABSTRACT: Lysosomal storage disorders (LSDs) are a very heterogeneous group of hereditary disorders. The diagnostic process usually involves complex sampling, processing, testing, and validation procedures, performed by specialized laboratories only, which causes great limitations in reaching a diagnosis for patients affected by these diseases.There are few studies about LSDs in Colombia. The diagnostic limitations often make medical practitioners disregard the possibility of these disorders while diagnosing their patients. The current study documents the results of a 7-year screening in high-risk patients, aimed to detect LSDs using dried blood spots (DBS) collected on filter paper, with a micromethodology that facilitates diagnosis even with a large number of samples.The activities of ?-galactosidase A, ? glucosidase, ?-L-iduronidase, arylsulfatase B, ?-galactosidase, ?-glucosidase, total hexosaminidase, iduronate sulfatase, and chitotriosidase were analyzed in high-risk patients for lysosomal disease. The catalytic activity was evaluated with fluorometric micromethods using artificial substrates marked with 4-methylumbelliferone.The reference values for a control population were established for the enzymes listed above, and 242 patients were found to have an enzyme deficiency, guiding to the following diagnoses: Fabry disease (n = 31), Pompe disease (n = 16), Hurler Syndrome (n = 15), Maroteaux-Lamy Syndrome (n = 34), GM1 Gangliosidosis (n = 10), Morquio B (n = 1), Gaucher disease (n = 101), Sandhoff disease (n = 1), Mucolipidosis (n = 2), and Hunter Syndrome (n = 31). In conclusion, this protocol provides a comprehensive diagnostic approach which could be carried out in Colombia and made it available to medical services spread around the country, enabling the identification of a large number of patients affected by LSDs, which could potentially benefit from the therapeutic tools already available for many of these diseases.

SUBMITTER: Uribe A

PROVIDER: S-EPMC3755556 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Selective screening for lysosomal storage diseases with dried blood spots collected on filter paper in 4,700 high-risk colombian subjects.

Uribe Alfredo A Giugliani Roberto R

JIMD reports 20130423

Lysosomal storage disorders (LSDs) are a very heterogeneous group of hereditary disorders. The diagnostic process usually involves complex sampling, processing, testing, and validation procedures, performed by specialized laboratories only, which causes great limitations in reaching a diagnosis for patients affected by these diseases.There are few studies about LSDs in Colombia. The diagnostic limitations often make medical practitioners disregard the possibility of these disorders while diagnos ...[more]

PMID: 23609959

Similar Datasets

Project description:BACKGROUND: Real-time quantitative nucleic acid sequence-based amplification (QT-NASBA) is a sensitive method for detection of sub-microscopic gametocytaemia by measuring gametocyte-specific mRNA. Performing analysis on fresh whole blood samples is often not feasible in remote and resource-poor areas. Convenient methods for sample storage and transport are urgently needed. METHODS: Real-time QT-NASBA was performed on whole blood spiked with a dilution series of purified in-vitro cultivated gametocytes. The blood was either freshly processed or spotted on filter papers. Gametocyte detection sensitivity for QT-NASBA was determined and controlled by microscopy. Dried blood spot (DBS) samples were subjected to five different storage conditions and the loss of sensitivity over time was investigated. A formula to approximate the loss of Pfs25-mRNA due to different storage conditions and time was developed. RESULTS: Pfs25-mRNA was measured in time to positivity (TTP) and correlated well with the microscopic counts and the theoretical concentrations of the dilution series. TTP results constantly indicated higher amounts of RNA in filter paper samples extracted after 24 hours than in immediately extracted fresh blood. Among investigated storage conditions freezing at -20°C performed best with 98.7% of the Pfs25-mRNA still detectable at day 28 compared to fresh blood samples. After 92 days, the RNA detection rate was only slightly decreased to 92.9%. Samples stored at 37°C showed most decay with only 64.5% of Pfs25-mRNA detectable after one month. The calculated theoretical detection limit for 24 h-old DBS filter paper samples was 0.0095 (95% CI: 0.0025 to 0.0380) per ?l. CONCLUSIONS: The results suggest that the application of DBS filter papers for quantification of Plasmodium falciparum gametocytes with real-time QT-NASBA is practical and recommendable. This method proved sensitive enough for detection of sub-microscopic densities even after prolonged storage. Decay rates can be predicted for different storage conditions as well as durations.

Project description:BackgroundThe use of filter paper as a simple, inexpensive tool for storage and transportation of blood, 'Dried Blood Spots' or Guthrie cards, for diagnostic assays is well-established. In contrast, there are a paucity of diagnostic evaluations of dried cerebrospinal fluid (CSF) spots. These have potential applications in low-resource settings, such as Laos, where laboratory facilities for central nervous system (CNS) diagnostics are only available in Vientiane. In Laos, a major cause of CNS infection is Japanese encephalitis virus (JEV). We aimed to develop a dried CSF spot protocol and to evaluate its diagnostic performance using the World Health Organisation recommended anti-JEV IgM antibody capture enzyme-linked immunosorbent assay (JEV MAC-ELISA).Methodology and principal findingsSample volumes, spotting techniques and filter paper type were evaluated using a CSF-substitute of anti-JEV IgM positive serum diluted in Phosphate Buffer Solution (PBS) to end-limits of detection by JEV MAC-ELISA. A conventional protocol, involving eluting one paper punch in 200 μl PBS, did not detect the end-dilution, nor did multiple punches utilising diverse spotting techniques. However, pre-cut filter paper enabled saturation with five times the volume of CSF-substitute, sufficiently improving sensitivity to detect the end-dilution. The diagnostic accuracy of this optimised protocol was compared with routine, neat CSF in a pilot, retrospective study of JEV MAC-ELISA on consecutive CSF samples, collected 2009-15, from three Lao hospitals. In comparison to neat CSF, 132 CSF samples stored as dried CSF spots for one month at 25-30 °C showed 81.6% (65.7-92.3 95%CI) positive agreement, 96.8% (91.0-99.3 95%CI) negative agreement, with a kappa coefficient of 0.81 (0.70-0.92 95%CI).Conclusions/significanceThe novel design of pre-cut filter paper saturated with CSF could provide a useful tool for JEV diagnostics in settings with limited laboratory access. It has the potential to improve national JEV surveillance and inform vaccination policies. The saturation of filter paper has potential use in the wider context of pathogen detection, including dried spots for detecting other analytes in CSF, and other body fluids.

Project description:BackgroundGlobal estimates for cholera annually approximate 4 million cases worldwide with 95,000 deaths. Recent outbreaks, including Haiti and Yemen, are reminders that cholera is still a global health concern. Cholera outbreaks can rapidly induce high death tolls by overwhelming the capacity of health facilities, especially in remote areas or areas of civil unrest. Recent studies demonstrated that stool specimens preserved on filter paper facilitate molecular analysis of Vibrio cholerae in resource limited settings. Specimens preserved in a rapid, low-cost, safe and sustainable manner for sequencing provides previously unavailable data about circulating cholera strains. This may ultimately contribute new information to shape public policy response on cholera control and elimination.Methodology/principal findingsWhole genome sequencing (WGS) recovered close to a complete sequence of the V. cholerae O1 genome with satisfactory genome coverage from stool specimens enriched in alkaline peptone water (APW) and V. cholerae culture isolates, both spotted on filter paper. The minimum concentration of V. cholerae DNA sufficient to produce quality genomic information was 0.02 ng/μL. The genomic data confirmed the presence or absence of genes of epidemiological interest, including cholera toxin and pilus loci. WGS identified a variety of diarrheal pathogens from APW-enriched specimen spotted filter paper, highlighting the potential for this technique to explore the gut microbiome, potentially identifying co-infections, which may impact the severity of disease. WGS demonstrated that these specimens fit within the current global cholera phylogenetic tree, identifying the strains as the 7th pandemic El Tor.ConclusionsWGS results allowed for mapping of short reads from APW-enriched specimen and culture isolate spotted filter papers. This provided valuable molecular epidemiological sequence information on V. cholerae strains from remote, low-resource settings. These results identified the presence of co-infecting pathogens while providing rare insight into the specific V. cholerae strains causing outbreaks in cholera-endemic areas.

Dataset Information

Selective screening for lysosomal storage diseases with dried blood spots collected on filter paper in 4,700 high-risk colombian subjects.

Publications

Selective screening for lysosomal storage diseases with dried blood spots collected on filter paper in 4,700 high-risk colombian subjects.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets