The clinical and molecular spectrum of galactosemia in patients from the Cape Town region of South Africa

BACKGROUND: The objective of this study was to document the clinical, laboratory and genetic features of galactosemia in patients from the Cape Town metropolitan region. METHODS: Diagnoses were based on thin layer chromatography for galactosuria/galactosemia and assays of erythrocyte galactose-1-phosphate uridyltransferase (GALT) and galactokinase activities. Patients were screened for the common S135L and Q188R transferase gene mutations, using PCR-based assays. Screening for the S135L mutation in black newborns was used to estimate the carrier rate for galactosemia in black South Africans. RESULTS: A positive diagnosis of galactosemia was made in 17 patients between the years 1980 to 2001. All had very low or absent galactose-1-phosphate uridyltransferase (GALT) activity, and normal galactokinase levels. The mean age at diagnosis was 5.1 months (range 4 days to 6.5 months). A review of 9 patients showed that hepatomegaly (9/9), and splenomegaly, failure to thrive, developmental delay, bilateral cataracts (6/9) were the most frequent features at diagnosis. Six had conjugated hyperbilirubinemia. Four experienced invasive E. coli infection before diagnosis. Ten patients were submitted to DNA analysis. All 4 black patients and 2 of mixed extraction were homozygous for the S135L allele, while all 3 white patients were homozygous for the Q188R allele. The remaining patient of mixed extraction was heterozygous for the Q188R allele. The estimated carrier frequency of the S135L mutation in 725 healthy black newborns was 1/60. CONCLUSIONS: In the absence of newborn screening the delay in diagnosis is most often unacceptably long. Also, carrier frequency data predict a galactosemia incidence of approximately 1/14 400 for black newborns in the Cape Metropole, which is much higher than the current detection rate. It is thus likely that many patients go undetected

Exceptional mobility of an advancing rhyolitic obsidian flow at Cordon Caulle volcano in Chile:observations from Cordón Caulle, Chile, 2011-2013.

The emplacement mechanisms of rhyolitic lava flows are enigmatic and, despite high lava viscosities and low inferred effusion rates, can result in remarkably, laterally extensive (>30 km) flow fields. Here we present the first observations of an active, extensive rhyolitic lava flow field from the 2011–2012 eruption at Cordón Caulle, Chile. We combine high-resolution four-dimensional flow front models, created using automated photo reconstruction techniques, with sequential satellite imagery. Late-stage evolution greatly extended the compound lava flow field, with localized extrusion from stalled, ~35 m-thick flow margins creating >80 breakout lobes. In January 2013, flow front advance continued ~3.6 km from the vent, despite detectable lava supply ceasing 6–8 months earlier. This illustrates how efficient thermal insulation by the lava carapace promotes prolonged within-flow horizontal lava transport, boosting the extent of the flow. The unexpected similarities with compound basaltic lava flow fields point towards a unifying model of lava emplacement

Avaliação econômica em saúde: triagem neonatal da galactosemia Newborn screening for galactosemia: a health economics evaluation

Este trabalho avalia a eficiência da adição do exame da galactosemia junto ao Teste do Pezinho. Baseado na incidência média estimada de galactosemia, de 1:19.984 recém-nascidos, no Estado de São Paulo, Brasil, este estudo desenvolve um modelo de análise de custo-benefício, utilizando a relação benefício/custo (B/C), a taxa de juros de 9,25% ao ano para descapitalização dos resultados obtidos. Também se realiza uma análise de sensibilidade, em função da variação da taxa de juros entre 0 e 20% e do intervalo de 95% de confiança da incidência da galactosemia (1:7.494 a 1:59.953 recém-nascidos). A economia obtida com a melhora da saúde das crianças doentes identificadas precocemente é superior aos custos (B/C = 1,33), caracterizando como eficiente a política de adição do exame neonatal para galactosemia no Teste do Pezinho. Quanto menor a taxa de juros vigente na economia, mais eficiente é a política de triagem neonatal, não considerados os custos sociais intangíveis evitados.<br>This study assesses the efficiency of the galactosemia add-on test in neonatal screening performed on regular Guthrie card blood spots. Based on estimated average incidence of galactosemia (1:19,984 newborns) in São Paulo State, Brazil, the study develops a cost-benefit analysis model, using a B/C ratio and a 9.25% annual interest rate in order to decapitalize the results. Sensitivity analysis is also performed, varying (as a function of the interest or discount rate) from 0 and 20% and according to the 95% confidence interval (1:7,494-1:59,953 newborns). The results show that the savings obtained by improved health of galactosemic patients detected early by add-on neonatal screening is superior to the costs (B/C=1.33), characterizing galactosemia add-on testing in neonatal screening as an efficient policy. The lower the prevailing interest rate in the economy, the more efficient the neonatal screening policy