Planum temporale, planum parietale and dichotic listening in dyslexia

A reduction or reversal of the normal leftward asymmetry of the planum temporale (PT) has been claimed to be typical of dyslexia, although some recent studies have challenged this view. In a population-based study of 20 right-handed dyslexic boys and 20 matched controls, we have measured the PT and the adjacent planum parietale (PP) region in sagittal magnetic resonance images. For the PT, mean left and right areas and asymmetry coefficients were compared. Since a PP area often could not be identified in one or both hemispheres, a qualitative comparison was used for this region. The total planar area (sum of PT and PP) was also compared between the two groups. A dichotic listening (DL) test with consonant–vowel syllables was administered to assess functional asymmetry of language. The results showed a mean leftward PT asymmetry in both the dyslexic and the control group, with no significant difference for the degree of PT asymmetry. Planned comparisons revealed however, a trend towards smaller left PT in the dyslexic group. In control children, but not in the dyslexic children, a significant correlation between PT asymmetry and reading was observed. A mean leftward asymmetry was also found for the total planar area, with no difference between the groups for the degree of asymmetry. Significantly fewer dyslexic children than control children showed a rightward asymmetry for the PP region. Both groups showed a normal right ear advantage on the DL task, with no significant difference for DL asymmetry. No significant correlation was observed between PT asymmetry and DL asymmetry. The present population-based study adds to recent reports of normal PT asymmetry in dyslexia, but indicates that subtle morphological abnormalities in the left planar area may be present in this condition.     

Vitamin D receptor allele combinations influence genetic susceptibility to type 1 diabetes in Germans

Vitamin D has been shown to exert manifold immunomodulatory effects. Because type 1 diabetes is regarded to be immune-mediated and vitamin D prevents the development of diabetes in the NOD mouse, we investigated the role of the vitamin D receptor (VDR) gene as a candidate for type 1 diabetes susceptibility. A total of 152 Caucasian families with at least one affected offspring were genotyped for four VDR restriction-site polymorphisms (FokI, BsmI, ApaI, and TaqI). Whereas the BsmI, ApaI, and TaqI polymorphisms are in strong linkage disequilibrium with each other, no significant linkage disequilibrium with the FokI site was observed. Extended transmission disequilibrium testing (ETDT) was used to detect preferential transmission of allelic combinations to affected offspring. We found significant haplotype-wise ETDT results for the BsmI/ApaI/TaqI (chi2 = 18.886, df = 7, P = 0.0086), the BsmI/TaqI (chi2 = 8.373, df = 3, P = 0.0389), and theApaI/TaqI (chi2 = 17.182, df = 3, P = 0.0006) haplotypes. The "At" and "Bt" alleles confer an increased risk, whereas "AT" and "at" are protective. The combination with the strongest susceptibility was the "BAt" haplotype (64% transmitted, P = 0.0106). Analysis of the FokI site does not provide more information on susceptibility (FokI/BsmI/ApaI/TaqI [chi2 = 24.702, df = 15, P = 0.0541]). These findings suggest a linkage of VDR itself or a nearby gene with type 1 diabetes susceptibility in Germans, confirming respective observations previously made in Indian Asians.     

Risk and risk factors for epilepsy in shunt-treated children with hydrocephalus

ObjectEpilepsy is a major comorbidity in children with hydrocephalus (HC) and has a serious impact on their developmental outcomes. There are variable influencing factors, thus the individual risk for developing epilepsy remains unclear. Our aim was to analyse risk factors for developing epilepsy in children with shunted HC.MethodsA retrospective, single-centre analysis of 361 patients with the diagnosis of HC was performed. Age at HC diagnosis, shunt treatment, development of epilepsy, epilepsy course, and the aetiology of HC were considered. The influence of shunt therapy, including its revisions and complications, on the development of epilepsy was investigated.ResultsOne-hundred forty-three patients with HC (n = 361) had a diagnosis of epilepsy (39.6%). The median age at the first manifestation of epilepsy was 300 days (range:1–6791; Q1:30, Q3: 1493). The probability of developing epilepsy after HC decreases with increasing age. The most significant influence on the development of epilepsy is that of the HC itself and its underlying aetiology (HR 5.9; 95%-CI [3–10.5]; p < 0.001). Among those, brain haemorrhage is associated with the highest risk for epilepsy (HR 7.9; 95%-CI [4.2–14.7]; p < 0.01), while shunt insertion has a lower influence (HR 1.5; 95%-CI [0.99; 2.38]; p = 0.06). The probability of epilepsy increases stepwise per shunt revision (HR 2.0; p = 0.03 after 3 or more revisions). Five hundred days after the development of HC, 20% of the children had a diagnosis of epilepsy. Shunt implantation at a younger age has no significant influence on the development of epilepsy nor does sex.ConclusionChildren with HC are at high risk for developing epilepsy. The development of epilepsy is correlated mainly with HC's underlying aetiology. The highest risk factor for the development of epilepsy seems to be brain haemorrhage. The age at shunt implantation appears to be unrelated to the development of epilepsy, while structural brain damage at a young age, shunt revisions and complications are independent risk factors. The onset of epilepsy is most likely to take place within the first 500 days after the diagnosis of HC.     

Herbal hepatotoxicity: Analysis of cases with initially reported positive re-exposure tests

BackgroundPositive re-exposure tests are diagnostic hallmarks for hepatotoxicity.ObjectiveTo test validity of positive re-exposures in herb induced liver injury.MethodsWe searched Medline database for cases of herb induced liver injury with positive re-exposures and analysed 34 cases for positive re-exposure test criteria of baseline alanine aminotransferase < 5N before re-exposure, and re-exposure alanine aminotransferase ≥ 2× baseline alanine aminotransferase. Re-exposure test was negative, if baseline alanine aminotransferase < 5N combined with re-exposure alanine aminotransferase < 2× baseline alanine aminotransferase, or if baseline alanine aminotransferase ≥ 5N regardless of the re-exposure alanine aminotransferase including no available re-exposure alanine aminotransferase result.ResultsIn 21/34 cases (61.8%), criteria for a positive re-exposure were fulfilled, with negative tests in 6/34 cases (17.6%) or uninterpretable ones in 7/34 cases (20.6%). Confirmed positive re-exposure tests established potential of herb induced liver injury for Aloe, Chaparral, Chinese herbal mixtures, Chinese Jin Bu Huan, Chinese Syo Saiko To, Germander, Greater Celandine, Green tea, Kava, Mistletoe, Polygonum multiflorum, and Senna, with up to 4 case reports per herb.ConclusionsAmong 34 cases of herb-induced liver injury with initially reported positive re-exposure tests, 61.8% of the cases actually fulfilled established test criteria and provided firm diagnoses of herb induced liver injury by various herbs.     

Limitations of platform assays to measure serum 25OHD level impact on guidelines and practice decision making

ContextLiquid Chromatography Mass Spectroscopy (LC-MS/MS) is the preferred method to measure 25 hydroxyvitamin D (25OHD) levels, but laboratories are increasingly adopting automated platform assays.ObjectiveWe assessed the performance of commonly used automated immunoassays, with that of LC-MS/MS, and the National Institute of Standards and Technology (NIST) reference values, to measure 25OHD levels.Methods/SettingWe compared serum 25OHD levels obtained from 219 elderly subjects, enrolled in a vitamin D trial, using the Diasorin Liaison platform assay, and the tandem LC-MS/MS method. We also assessed the performance of the Diasorin and Roche automated assays, expressed as mean % bias from the NIST standards, based on the vitamin D External Quality Assessment Scheme (DEQAS) reports, from 2013 to 2017.ResultsSerum 25OHD levels were significantly lower in the Diasorin compared to LC-MS/MS assay at baseline, 18.5 ± 7.8 vs 20.5 ± 7.6 ng/ml (p < 0.001), and all other time points. Diasorin (25OHD) = 0.76 × LC-MS/MS (25OHD) + 4.3, R² = 0.596. The absolute bias was independent of 25OHD values, and the pattern unfit for any cross-calibration. The proportion of subjects considered for vitamin D treatment based on pre-set cut-offs differed significantly between the 2 assays. There also was wide variability in the performance of both automated assays, compared to NIST reference values.ConclusionThe performance of most widely used automated assays is sub-optimal. Our findings underscore the pressing need to re-consider current practices with regard to 25OHD measurements, interpretation of results from research studies, meta-analyses, the development of vitamin D guidelines, and their relevance to optimizing health.     

Long‐term tooth loss in periodontally compromised but treated patients according to the type of prosthodontic treatment. A retrospective study

If prosthodontic treatment is considered after periodontal therapy, the questions arise i) does prosthodontic treatment affect the treatment outcome of the dentition in general and ii) which type of prosthesis is related to best treatment outcome of abutment teeth? Our goal was to compare long‐term tooth loss after comprehensive periodontal therapy in patients with or without prosthodontic treatment. Ninety patients' charts with a total of 1937 teeth who had received comprehensive periodontal treatment 5–17 years ago by the same periodontist were retrospectively evaluated. Sixty‐five patients received fixed dental prostheses (FDP; n = 29) and/or removable partial dentures anchored with clips (RPDC; n = 25) or double crowns (RPDD; n = 25). Twenty‐five patients were also periodontally compromised but treated without prosthodontic treatment and served as a control group. A total of 317 teeth and 70 abutment teeth were lost during 9·7 ± 4·1 years of observation. Thereof, 273 teeth and 48 abutment teeth were lost due to periodontal reasons. Mean tooth loss amounted to 1·2 ± 1·5 (controls) and 4·4 ± 3·4 (partial dentures). Abutment tooth loss was 0·4 ± 1·1 (FDP), 1·0 ± 1·2 (RPDC) and 1·3 ± 1·0 (RPDD). Poisson regressions identified prosthodontic treatment, age, socio‐economic status, diabetes mellitus, mean initial bone loss and aggressive periodontitis as factors significantly contributing to tooth loss. Age, diabetes and non‐compliance contributed to abutment tooth loss. Not considering biomechanical factors, patients with prosthodontic reconstructions under long‐term supportive periodontal therapy were at higher risk for further tooth loss than patients without prostheses. Not only the type of partial denture but also the patient‐related risk factors were associated with abutment tooth loss.