Clinical diagnostic exome sequencing in dystonia: Genetic testing challenges for complex conditions.

Patients with dystonia are particularly appropriate for diagnostic exome sequencing (DES), due to the complex, diverse features and genetic heterogeneity. Personal and family history data were collected from test requisition forms and medical records from 189 patients with reported dystonia and available family members received for clinical DES. Of them, 20.2% patients had a positive genetic finding associated with dystonia. Detection rates for cases with isolated and combined dystonia were 22.4% and 25.0%, respectively. 71.4% of the cohort had co-occurring non-movement-related findings and a detection rate of 24.4%. Patients with childhood-onset dystonia trended toward higher detection rates (31.8%) compared to infancy (23.6%), adolescence (12.5%), and early-adulthood onset (16%). Uncharacterized gene findings were found in 6.7% (8/119) of cases that underwent analysis for genes without an established disease relationship. Patients with intellectual disability/developmental delay, seizures/epilepsy and/or multifocal dystonia were more likely to have positive findings (P = .0093, .0397, .0006). Four (2.1%) patients had findings in two genes, and seven (3.7%) had reclassification after the original report due to new literature, new clinical information or reanalysis request. Pediatric patients were more likely to have positive findings (P = .0180). Our observations show utility of family-based DES in patients with dystonia and illustrate the complexity of testing.

Clinical validity assessment of genes for inclusion in multi-gene panel testing: A systematic approach.

BACKGROUND: Advances in sequencing technology have led to expanded use of multi-gene panel tests (MGPTs) for clinical diagnostics. Well-designed MGPTs must balance increased detection of clinically significant findings while mitigating the increase in variants of uncertain significance (VUS). To maximize clinical utililty, design of such panels should include comprehensive gene vetting using a standardized clinical validity (CV) scoring system. METHODS: To assess the impact of CV-based gene vetting on MGPT results, data from MGPTs for cardiovascular indications were retrospectively analyzed. Using our CV scoring system, genes were categorized as having definitive, strong, moderate, or limited evidence. The rates of reported pathogenic or likely pathogenic variants and VUS were then determined for each CV category. RESULTS: Of 106 total genes, 42% had definitive, 17% had strong, 29% had moderate, and 12% had limited CV. The detection rate of variants classified as pathogenic or likely pathogenic was higher for genes with greater CV, while the VUS rate showed an inverse relationship with CV score. No pathogenic or likely pathogenic findings were observed in genes with a limited CV. CONCLUSION: These results demonstrate the importance of a standardized, evidence-based vetting process to establish CV for genes on MGPTs. Using our proposed system may help to increase the detection rate while mitigating higher VUS rates.

Investigating the effect of AS03 adjuvant on the plasma cell repertoire following pH1N1 influenza vaccination.

Influenza pandemics require rapid deployment of effective vaccines for control. Adjuvants such as AS03 improve vaccine immunogenicity, but this mechanism is poorly understood. We used high-throughput B cell receptor sequencing of plasma cells produced following AS03-adjuvanted and non-adjuvanted 2009 pandemic H1N1 vaccination, as well as pre-pandemic seasonal influenza vaccination to elucidate the effect of the adjuvant on the humoral immune response. By analyzing mutation levels, it was possible to distinguish sequences from cells that were recently activated from naïve B cells from those that were activated by memory recall. We show that the adjuvant functions through two mechanisms. First, the adjuvant stimulates increased activation of naïve B cells, thus reducing immune interference with previous vaccine responses. Second, the adjuvant is able to increase the adaptability of the recalled cells to give improved specificity to the new vaccine antigen. We thus show how AS03 enhances pH1N1 immune responses, and reduces immune interference.

Endoscopic endonasal approach for the treatment of schwannomas of the pterygopalatine fossa: case report and review of the literature.

INTRODUCTION: Pterygopalatine fossa (PPF) schwannomas are rare lesions most often arising from branches of the trigeminal nerve. Symptomatic lesions have been traditionally treated by conventional external approaches. However, the development of an expanded endonasal approach (EEA) enables skull base surgeons to reach these deeply seated lesions via a different route with its own advantages and drawbacks. METHODS: Case report and review of the literature. CASE DESCRIPTION: A 41-year-old woman presented with a 6-year history of right facial pain and numbness. Her symptoms had increased progressively over a year, and she recently had developed right-sided otalgia. MRI revealed a right PPF mass, hypointense on T1 and T2 sequences with homogeneous enhancement following the use of gadolinium. A biopsy, attempted at another institution, was considered non-diagnostic. We totally removed the lesion through an endoscopic endonasal transmaxillary approach. Final pathology confirmed the diagnosis of schwannoma. Post-operatively, the patient noted a significant improvement of her facial pain (V2 territory). CONCLUSION: The endonasal endoscopic transmaxillary approach provides adequate access to the PPF, thus enabling safe tumor removal with less morbidity than conventional routes.

The supraorbital approach for recurrent or residual suprasellar tumors.

BACKGROUND: Suprasellar tumors can be removed through a variety of approaches including conventional frontotemporal craniotomies, the transsphenoidal route, or the supraorbital (SO) eyebrow craniotomy. Herein we assess the utility of the SO route for recurrent or residual suprasellar tumors previously treated by an alternative route. MATERIAL AND METHODS: A retrospective analysis of all consecutive patients who underwent an SO approach for removal of a recurrent/residual tumor was undertaken. RESULTS: Between December 2007 and February 2010, 11 patients underwent an SO craniotomy for a recurrent or growing residual tuberculum sellae meningioma (n=7) or craniopharyngioma (n=4). All 11 patients had prior craniotomies, 5 had transsphenoidal surgery, 6 had radiation treatment, and 1 had chemotherapy. In the last 5 cases, the endoscope was used in addition to the microscope for intraoperative visualization. 3 patients underwent decompression of multicystic craniopharyngiomas and the remaining 8 patients had tumor debulking, all achieving 70% or more tumor removal. Of 9 patients with preoperative visual deterioration, 6 (67%) had improvement and no patient had visual worsening. No new adenohypophysis or neurohypophysis dysfunction was noted. One patient had a postoperative CSF leak requiring reoperation. CONCLUSION: The SO approach should be considered as a safe and effective alternative route for recurrent or residual suprasellar tumors previously treated by conventional craniotomy or TS surgery. It typically offers a simplified trajectory that minimizes scar tissue from prior approaches and provides excellent access for optic apparatus decompression. Endoscopy is helpful to visualize hidden tumor remnants and maximize safe tumor removal.

Haemophilus influenzae type b carriage and novel bacterial population structure among children in urban Kathmandu, Nepal.

Haemophilus influenzae type b (Hib) is a major cause of invasive bacterial infection in children that can be prevented by a vaccine, but there is still uncertainty about its relative importance in Asia. This study investigated the age-specific prevalence of Hib carriage and its molecular epidemiology in carriage and disease in Nepal. Oropharyngeal swabs were collected from children in Kathmandu, Nepal, from 3 different settings: a hospital outpatient department (OPD), schools, and children's homes. Hib was isolated using Hib antiserum agar plates, and serotyping was performed with latex agglutination. Hib isolates from children with invasive disease were obtained during active microbiological surveillance at Patan Hospital, Kathmandu, Nepal. Genotyping of disease and carriage isolates was undertaken using multilocus sequence typing (MLST). Swabs were taken from 2,195 children, including 1,311 children at an OPD, 647 children attending schools, and 237 children in homes. Overall, Hib was identified in 5.0% (110/2,195; 95% confidence interval [95% CI], 3.9% to 6.4%). MLST was performed on 108 Hib isolates from children carrying Hib isolates and 15 isolates from children with invasive disease. Thirty-one sequence types (STs) were identified, and 20 of these were novel STs. The most common ST isolates were sequence type 6 (ST6) and the novel ST722. There was marked heterogeneity among the STs from children with disease and children carrying Hib. STs identified from invasive infections were those commonly identified in carriage. This study provides evidence of Hib carriage among children in urban Nepal with genetically diverse strains prior to introduction of universal vaccination. The Hib carriage rate in Nepal was similar to the rates observed in other populations with documented high disease rates prior to vaccination, supporting implementation of Hib vaccine in Nepal in 2009.

Clinical profile of invasive pneumococcal diseases in Patan Hospital, Nepal.

BACKGROUND: Pneumococcal infection is one of the leading causes of pneumonia, meningitis and septicemia in developing countries. It accounts for one million deaths each year in children. OBJECTIVES: The objective of this study is to see the clinical profile of invasive pneumococcal disease, antibiotics sensitivity pattern and prevalent serotypes in children admitted at Patan Hospital. METHODS: This is a retrospective analytical study conducted in the department of Paediatrics, Patan hospital. The lab data of those children who grew pneumococci in their blood, cerebrospinal fluid or body fluids over a period of 3 years (January 2007 to Dec 2009) were collected and the case files were then studied. RESULTS: Out of 42 cases of invasive pneumococcal diseases studied admitted diagnoses included pneumonia, febrile seizure, bacteremia or septicemia, meningitis, acute gastroenteritis and glomerulonephritis. Twenty seven of them were children under five. The male to female ratio was 1.7:1. On investigation 64%, 52% and 5% of the patients had leucocytosis, anaemia, and leucopenia respectively. Twenty six of them had radiological changes suggestive of pneumonia. Streptococcus pneumoniae grew in 38 blood samples, 5 cerebrospinal fluid and 3 pleural fluids. Almost all of these isolates were sensitive to penicillin, cefotaxime, amoxycillin, choloramphenicol, erythromycin and ofloxacin and resistant to cotrimoxazole and gentamicin. Pneumococcal serotypes found in our study were 1, 14, 5, 23B, 6B, 8, 9A, 9V, 10A, 15 and 23F (11 serotypes). CONCLUSIONS: Penicillin is still the most effective antibiotic for streptococcal infection in our study. Of the pneumococcal serotypes identified; 36% were covered by the 7-valent pneumococcal conjugate vaccine, 54% each by PCV-10 and PCV-13, and 72% by the e 23 valent vaccines.

Vidian nerve neurofibroma removed via a transpterygoid approach.

BACKGROUND: Lesions originating in the vidian canal are extremely rare. Most frequently, they are extensions from contiguous carcinomas. We present a rare case of a vidian nerve neurofibroma and discuss its surgical management. CASE REPORT: A 62-year-old woman with a history of a basal cell skin cancer was evaluated for bilateral tinnitus. Imaging revealed a left-sided lesion at the medial aspect of the pterygoid process base, over the vidian canal. Under image-guidance, an endonasal endoscopic transpterygoid approach was performed. The histopathological examination supported the diagnosis of neurofibroma. CONCLUSION: Benign nerve sheath tumors of the vidian nerve should be considered in the differential diagnosis of a vidian canal lesion. Given the propensity of more aggressive tumors, a tissue diagnosis should be warranted in order to coordinate appropriate subsequent treatment. The expanded endonasal transpterygoid approach offers a safe, less invasive, and effective route to perform the excisional biopsy of such a lesion.

Seroprotection against serogroup C meningococcal disease in adolescents in the United Kingdom: observational study.

OBJECTIVE: To determine the persistence of bactericidal antibody titres following immunisation with serogroup C meningococcal glycoconjugate vaccine at age 6-15 years in order to examine changes in persistence of antibodies with age. DESIGN: Observational study. SETTING: Secondary and tertiary educational institutions in the United Kingdom. PARTICIPANTS: Healthy adolescents aged 11-20 years previously immunised between 6 and 15 years of age with one of the three serogroup C meningococcal vaccines. INTERVENTION: Serum obtained by venepuncture. MAIN OUTCOME MEASURES: Percentage of participants with (rabbit complement) serum bactericidal antibody titres of at least 1:8; geometric mean titres of serogroup C meningococcal serum bactericidal antibody. RESULTS: Five years after immunisation, 84.1% (95% confidence interval 81.6% to 86.3%) of 987 participants had a bactericidal antibody titre of at least 1:8. Geometric mean titres of bactericidal antibody were significantly lower in 11-13 year olds (147, 95% confidence interval 115 to 188) than in 14-16 year olds (300, 237 to 380) and 17-20 year olds (360, 252 to 515) (P<0.0001 for both comparisons). Within these age bands, no significant difference in geometric mean titres of bactericidal antibody between recipients of the different serogroup C meningococcal vaccines was seen. More than 70% of participants had received a vaccine from one manufacturer; in this cohort, geometric mean titres were higher in those immunised at aged 10 years or above than in those immunised before the age of 10. CONCLUSIONS: Higher concentrations of bactericidal antibody are seen five years after immunisation with serogroup C meningococcal vaccine at age 10 years or above than in younger age groups, possibly owing to immunological maturation. This provides support for adolescent immunisation programmes to generate sustained protection against serogroup C meningococcal disease not only for the vaccine recipients but also, through the maintenance of herd immunity, for younger children.

Neuropathological findings in cats with clinically suspect but histologically unconfirmed feline spongiform encephalopathy.

Central nervous system (CNS) tissues from 192 cats with neurological signs were examined histologically, and tissues from 173 of them were later examined immunohistochemically as part of a survey to determine the prevalence of feline spongiform encephalopathy (FSE). One of the cats was from Norway and the others were from Great Britain. The most commonly recorded clinical signs were ataxia, behavioural changes and epilepsy, but none of the cats had histopathological evidence of FSE. The most common organic CNS lesions were non-suppurative encephalomyelitis in 28 per cent, neoplasia in 15 per cent and a heterogeneous group of degenerative encephalopathies in 9 per cent of the cats. A range of minor histological lesions of uncertain significance was also observed. No histological lesions were observed in the tissues of 63 (33 per cent) of the cats. Disease-specific prion protein (PrP(Sc)) was observed in only one of the 173 cats examined by immunohistochemistry.

Adrenal necrosis in a dog receiving trilostane for the treatment of hyperadrenocorticism.

Clinical and biochemical changes suggestive of hypoadrenocorticism were observed in a 10-year-old male neutered Staffordshire bull terrier shortly after beginning therapy with trilostane for the treatment of hyperadrenocorticism. The dog's condition was stabilised with intravenous fluids, fludrocortisone and prednisolone. An exploratory laparotomy and excisional biopsy of the left adrenal gland were performed. Histopathological analysis showed adrenal cortical necrosis with reactive inflammation and fibrosis. Trilostane is a reversible inhibitor of steroid synthesis and this complication has not been reported previously. Clinicians should be aware that trilostane therapy may result in adrenal necrosis but that prompt treatment might correct a life-threatening situation.