[The value of re-evaluation and thorough family history taking for the diagnostic work-up of chorea]. / Het diagnostisch proces bij chorea: het belang van heroverwegen en de familieanamnese.

The differential diagnosis of chorea encompasses a broad range of disorders. In psychiatry, tardive dyskinesia may be difficult to discern from other causes, particularly when the family history is negative. A 59-year-old man with an unclear medical history had been using risperidone for over a decade when we first saw him. He presented with severe dyskinesia in all extremities. The family history for neuropsychiatric disorders was negative. We interpreted the movement disorder as tardive dyskinesia, but later he turned out to suffer from Huntington’s disease. To improve diagnostic accuracy, we should have more frequently re-evaluated the differential diagnosis and our family history should have been more thorough. We outline the diagnostic considerations in patients presenting with chorea. Finally, we highlight the value of diagnostic re-evaluation and thorough family history taking to optimize diagnostic accuracy in neuropsychiatry.

Similar outcomes to primary total knee arthroplasty achievable for aseptic revision using the same primary posterior-stabilised prosthesis at a mean follow-up of 49 months.

PURPOSE: The aim of the study was to compare clinical and radiological outcomes between primary and aseptic revision TKAs using the same posterior-stabilised (PS) prosthesis. The authors hypothesised similar outcomes between both groups for selected patients. METHODS: This retrospective, case-control study assessed 36 patients who underwent aseptic revision TKA compared to a match group of 72 primary TKA. Both groups had the same PS design implant (ANATOMIC®, Amplitude, Valence, France). The International Knee Society (IKS) score, radiological outcomes (postoperative alignment, patellar tilt and radiolucent lines), re-intervention and revision rate were compared between the two groups with a minimum follow-up of 3 years. RESULTS: The final study cohort included 29 patients and 63 patients respectively in the revision and primary group, with a mean follow-up of 49.1 months (range 36.1-69). Postoperatively, there was no significant difference in IKS scores between the two groups [169.8 for the revision group and 179.6 for the primary group (p = 0.09)]. No statistical difference was observed for post-operative satisfaction 86.2% versus 92.1% (p = 0.46). Between the two groups, there was no difference in mean radiological assessment, including radiolucent lines (p = 0.7). There was no significant difference for overall implant survivorship 96.5% versus 100% (p = 0.13) at 36 months. CONCLUSION: Similar clinical, radiological and survivorship outcomes were found between rTKA and primary TKA groups using the same PS level of constraint in patients undergoing revision surgery for aseptic indications at 3-year follow-up. Use of PS implants in rTKA for the correct indication suggests this to be a safe approach at least in the medium term. LEVEL OF EVIDENCE: IV, retrospective case-control study.

Further audiovestibular characterization of DFNB77, caused by deleterious variants in LOXHD1, and investigation into the involvement of Fuchs corneal dystrophy.

This study focuses on further characterization of the audiovestibular phenotype and on genotype-phenotype correlations of DFNB77, an autosomal recessive type of hearing impairment (HI). DFNB77 is associated with disease-causing variants in LOXHD1, and is genetically and phenotypically highly heterogeneous. Heterozygous deleterious missense variants in LOXHD1 have been associated with late-onset Fuchs corneal dystrophy (FCD). However, up to now screening for FCD of heterozygous carriers in DFNB77 families has not been reported. This study describes the genotype and audiovestibular phenotype of 9 families with DFNB77. In addition, carriers within the families were screened for FCD. Fifteen pathogenic missense and truncating variants were identified, of which 12 were novel. The hearing phenotype showed high inter- and intrafamilial variation in severity and progression. There was no evidence for involvement of the vestibular system. None of the carriers showed (pre-clinical) symptoms of FCD. Our findings expand the genotypic and phenotypic spectrum of DFNB77, but a clear correlation between the type or location of the variant and the severity or progression of HI could not be established. We hypothesize that environmental factors or genetic modifiers are responsible for phenotypic differences. No association was found between heterozygous LOXHD1 variants and the occurrence of FCD in carriers.

Psychological impact of a genetic diagnosis on hearing impairment-An exploratory study.

OBJECTIVE: Genetic testing for hereditary hearing impairment has become more routinely available as a diagnostic tool in the outpatient clinic. However, little is known about the psychological impact of a genetic diagnosis. To evaluate this impact, an exploratory study was conducted. DESIGN: Prospectively, 48 individuals who underwent genetic testing for hereditary hearing impairment were included in this study. Study participants were asked to fill out the following questionnaires: Hospital Anxiety Depression Scale, Impact of Event Scale, Self-Efficacy 24, Illness Cognition Questionnaire and the Inventory for Social Reliance. Questionnaires were filled out on three occasions: before genetic testing, directly after counselling on either positive or negative test results, and six weeks thereafter. RESULTS: No significant differences were found between the group that received a genetic diagnosis for their hearing impairment and the group that did not. CONCLUSION: This study did not demonstrate differences between receiving a genetic diagnosis or not; however, special attention to psychological well-being should be offered to hearing-impaired patients who seek a genetic diagnosis for their hearing impairment. Additionally, the psychological impact of sensorineural hearing impairment might be greater than the impact of a genetic diagnosis itself. Based on the current exploratory study, there are no psychological reasons in favour of or against genetic testing for hereditary hearing impairment.

Features of autosomal recessive non-syndromic hearing impairment: a review to serve as a reference.

OBJECTIVE: Non-syndromic sensorineural hearing impairment is inherited in an autosomal recessive fashion in 75-85% of cases. To date, 61 genes with this type of inheritance have been identified as related to hearing impairment, and the genetic heterogeneity is accompanied by a large variety of clinical characteristics. Adequate counselling on a patient's hearing prognosis and rehabilitation is part of the diagnosis on the genetic cause of hearing impairment and, in addition, is important for the psychological well-being of the patient. TYPE OF REVIEW: Traditional literature review. DATA SOURCE: All articles describing clinical characteristics of the audiovestibular phenotypes of identified genes and related loci have been reviewed. CONCLUSION: This review aims to serve as a summary and a reference for counselling purposes when a causative gene has been identified in a patient with a non-syndromic autosomal recessively inherited sensorineural hearing impairment.

Genotype phenotype correlations for hearing impairment: approaches to management.

Hearing impairment is an extremely heterogeneous disorder, with both environmental as well as genetic causes. This review describes the known genes involved in non-syndromic hearing impairment and their genotype-phenotype correlations where possible. Furthermore, some of the more frequent syndromic forms of hearing impairment are described, in particular where they overlap with the non-syndromic forms. Given the heterogeneity of the disorder, together with the indistinguishable phenotypes for many of the genes, it is suggested that testing for mutations is performed using massive parallel sequencing techniques, either by a large targeted set of genes or by an exome wide analysis.

Genotype-phenotype correlations in spastic paraplegia type 7: a study in a large Dutch cohort.

Spastic paraplegia type 7 is an autosomal recessive neurodegenerative disorder mainly characterized by progressive bilateral lower limb spasticity and referred to as a form of hereditary spastic paraplegia. Additional disease features may also be observed as part of a more complex phenotype. Many different mutations have already been identified, but no genotype-phenotype correlations have been found so far. From a total of almost 800 patients referred for testing, we identified 60 patients with mutations in the SPG7 gene. We identified 14 previously unreported mutations and detected a high recurrence rate of several earlier reported mutations. We were able to collect detailed clinical data for 49 patients, who were ranked based on a pure versus complex phenotype, ataxia versus no ataxia and missense versus null mutations. A generally complex phenotype occurred in 69% of all patients and was associated with a younger age at onset (trend with P = 0.07). Ataxia was observed in 57% of all patients. We found that null mutations were associated with the co-occurrence of cerebellar ataxia (trend with P = 0.06). The c.1409 G > A (p.Arg470Gln) mutation, which was found homozygously in two sibs, was associated with a specific complex phenotype that included predominant visual loss due to optical nerve atrophy. Neuropathology in one of these cases showed severe degeneration of the optic system, with less severe degeneration of the ascending tracts of the spinal cord and cerebellum. Other disease features encountered in this cohort included cervical dystonia, vertical gaze palsy, ptosis and severe intellectual disability. In this large Dutch cohort, we seem to have identified the first genotype-phenotype correlation in spastic paraplegia type 7 by observing an association between the cerebellar phenotype of spastic paraplegia type 7 and SPG7 null alleles. An overlapping phenotypic presentation with its biological counterpart AFG3L2, which when mutated causes spinocerebellar ataxia type 28, is apparent and possibly suggests that abnormal levels of the SPG7 protein impact the function of the mitochondrial ATPases associated with diverse cellular activities-protease complex (formed by SPG7 and AFG3L2) in the cerebellum. In addition, a missense mutation in exon 10 resulted in predominant optical nerve atrophy, which might suggest deleterious interactions of this SPG7 variant with its substrate OPA1, the mutated gene product in optic atrophy type 1. Functional studies are required to further investigate these interactions.

Male pseudohermaphroditism due to a homozygous missense mutation of the luteinizing hormone receptor gene.

Leydig cell hypoplasia is a rare autosomal recessive condition that interferes with normal development of male external genitalia in 46,XY individuals. We have studied two Leydig cell hypoplasia patients (siblings born to consanguineous parents), and found them to be homozygous for a missense mutation (Ala593Pro) in the sixth transmembrane domain of the luteinizing hormone (LH) receptor gene. In vitro expression studies showed that this mutated receptor binds human choriogonadotropin with a normal KD, but the ligand binding does not result in increased production of cAMP. We conclude that a homozygous LH receptor gene mutation underlies the syndrome of autosomal recessive congenital Leydig cell hypoplasia in this family. These results have implications for the understanding of the development of the male genitalia.

Mutations in PTPN11, encoding the protein tyrosine phosphatase SHP-2, cause Noonan syndrome.

Noonan syndrome (MIM 163950) is an autosomal dominant disorder characterized by dysmorphic facial features, proportionate short stature and heart disease (most commonly pulmonic stenosis and hypertrophic cardiomyopathy). Webbed neck, chest deformity, cryptorchidism, mental retardation and bleeding diatheses also are frequently associated with this disease. This syndrome is relatively common, with an estimated incidence of 1 in 1,000-2,500 live births. It has been mapped to a 5-cM region (NS1) [corrected] on chromosome 12q24.1, and genetic heterogeneity has also been documented. Here we show that missense mutations in PTPN11 (MIM 176876)-a gene encoding the nonreceptor protein tyrosine phosphatase SHP-2, which contains two Src homology 2 (SH2) domains-cause Noonan syndrome and account for more than 50% of the cases that we examined. All PTPN11 missense mutations cluster in interacting portions of the amino N-SH2 domain and the phosphotyrosine phosphatase domains, which are involved in switching the protein between its inactive and active conformations. An energetics-based structural analysis of two N-SH2 mutants indicates that in these mutants there may be a significant shift of the equilibrium favoring the active conformation. This implies that they are gain-of-function changes and that the pathogenesis of Noonan syndrome arises from excessive SHP-2 activity.

Localization of the gene for Cowden disease to chromosome 10q22-23.

Cowden disease (CD) (MIM 158350), or multiple hamartoma syndrome, is a rare autosomal dominant familial cancer syndrome with a high risk of breast cancer. Its clinical features include a wide array of abnormalities but the main characteristics are hamartomas of the skin, breast, thyroid, oral mucosa and intestinal epithelium. The pathognomonic hamartomatous features of CD include multiple smooth facial papules, acral keratosis and multiple oral papillomas. The pathological hallmark of the facial papules are multiple trichilemmomas. Expression of the disease is variable and penetrance of the dermatological lesions is assumed to be virtually complete by the age of twenty. Central nervous system manifestations of CD were emphasized only recently and include megalencephaly, epilepsy and dysplastic gangliocytomas of the cerebellum (Lhermitte-Duclos disease, LDD). Early diagnosis is important since female patients with CD are at risk of developing breast cancer. Other lesions include benign and malignant disease of the thyroid, intestinal polyps and genitourinary abnormalities. To localize the gene for CD, an autosomal genome scan was performed. A total of 12 families were examined, resulting in a maximum lod score of 8.92 at theta = 0.02 with the marker D10S573 located on chromosome 10q22-23.

Affinity purification of in vivo assembled whirlin-associated protein complexes from the zebrafish retina.

Mutations in WHRN lead to Usher syndrome type 2d or to non-syndromic hearing impairment. The WHRN-encoded gene product whirlin directly interacts with the intracellular regions of the other two Usher syndrome type 2-associated proteins, usherin and ADGRV1. In photoreceptor cells, this protein complex constitutes fibrous links between the periciliary membrane and the connecting cilium. However, the molecular mechanism(s) of retinal degeneration due to compromised formation and function of the USH2-associated protein complex remains elusive. To unravel this pathogenic mechanism, we isolated and characterized whirlin-associated protein complexes from zebrafish photoreceptor cells. We generated transgenic zebrafish that express Strep/FLAG-tagged Whrna, a zebrafish ortholog of human whirlin, under the control of a photoreceptor-specific promoter. Affinity purification of Strep/FLAG-tagged Whrna and associated proteins from adult transgenic zebrafish retinas followed by mass spectrometry identified 19 novel candidate associated proteins. Pull down experiments and dedicated yeast two-hybrid assays confirmed the association of Whrna with 7 of the co-purified proteins. Several of the co-purified proteins are part of the synaptic proteome, which indicates a role for whirlin in the photoreceptor synapse. Future studies will elucidate which of the newly identified protein-protein interactions contribute to the development of the retinal phenotype observed in USH2d patients. SIGNIFICANCE: Since protein-protein interactions identified using targeted in vitro studies do not always recapitulate interactions that are functionally relevant in vivo, we established a transgenic zebrafish line that stably expresses a Strep/FLAG-tagged ortholog of human whirlin (SF-Whrna) in photoreceptor cells. Affinity purification of in vivo-assembled SF-Whrna-associated protein complexes from retinal lysates followed by mass spectrometry, identified 19 novel candidate interaction partners, many of which are enriched in the synaptic proteome. Two human orthologs of the identified candidate interaction partners, FRMPD4 and Kir2.3, were validated as direct interaction partners of human whirlin using a yeast two-hybrid assay. The strong connection of whirlin with postsynaptic density proteins was not identified in previous in vitro protein-protein interaction assays, presumably due to the absence of a biologically relevant context. Isolation and identification of in vivo-assembled whirlin-associated protein complexes from the tissue of interest is therefore a powerful methodology to obtain novel insight into tissue specific protein-protein interactions and has the potential to improve significantly our understanding of the function of whirlin and the molecular pathogenesis underlying Usher syndrome type 2.

A novel DFNB1 deletion allele supports the existence of a distant cis-regulatory region that controls GJB2 and GJB6 expression.

Eleven affected members of a large German-American family segregating recessively inherited, congenital, non-syndromic sensorineural hearing loss (SNHL) were found to be homozygous for the common 35delG mutation of GJB2, the gene encoding the gap junction protein Connexin 26. Surprisingly, four additional family members with bilateral profound SNHL carried only a single 35delG mutation. Previously, we demonstrated reduced expression of both GJB2 and GJB6 mRNA from the allele carried in trans with that bearing the 35delG mutation in these four persons. Using array comparative genome hybridization (array CGH), we have now identified on this allele a deletion of 131.4 kb whose proximal breakpoint lies more than 100 kb upstream of the transcriptional start sites of GJB2 and GJB6. This deletion, del(chr13:19,837,344-19,968,698), segregates as a completely penetrant DFNB1 allele in this family. It is not present in 528 persons with SNHL and monoallelic mutation of GJB2 or GJB6, and we have not identified any other candidate pathogenic copy number variation by arrayCGH in a subset of 10 such persons. Characterization of distant GJB2/GJB6 cis-regulatory regions evidenced by this allele may be required to find the 'missing' DFNB1 mutations that are believed to exist.

Hereditary spastic paraplegia due to SPAST mutations in 151 Dutch patients: new clinical aspects and 27 novel mutations.

BACKGROUND: In the clinically and genetically heterogeneous group of the hereditary spastic paraplegias (HSPs), mutations in the SPAST gene are most frequently found and cause a pure autosomal dominant form. OBJECTIVE: To provide the clinical and genetic characteristics of Dutch patients with HSP due to a SPAST mutation (SPG4). METHODS: SPAST mutation carriers were identified through a comprehensive national database search. Available medical records were reviewed. RESULTS: 151 mutation carriers carried 60 different changes in the SPAST gene, of which one was a known polymorphism, and 27 were novel. Missense mutations were most frequently found (39%). Clinical information was available from 72 mutation carriers. Age at onset ranged from 1 to 63 years with a bimodal peak distribution in the first decade and above age 30. The predominantly pure spastic paraplegia was accompanied by deep sensory disturbances and sphincter problems in almost 50%. An additional hand tremor was found in 10%. Patients with missense mutations and exon deletions did not reveal a distinctive phenotype. CONCLUSIONS: Dutch SPAST mutation carriers show a broad mutation spectrum, with 27 novel mutations in the present series. A bimodal peak distribution in age at onset was found and an accompanying tremor as peculiar feature of SPG4. The pathogenicity of S44L, the first exon 4 mutation, and a possible autosomal recessive mode of inheritance are discussed.

Postural instability in cerebellar ataxia: correlations of knee, arm and trunk movements to center of mass velocity.

The aim of this study was to investigate the correlations between body segment movements and center of mass (COM) velocity during pathological balance corrections of spinocerebellar ataxia (SCA) patients compared with controls, and to relate correlations indicating instability to EMG activity differences. Eighteen SCA patients and 21 age-matched controls were tested. Upright standing was perturbed using rotations of the support surface. We recorded body motion and surface EMG. For lateral perturbations peaks in COM lateral velocity were larger in SCA patients than controls. These peaks were correlated with increased ("hypermetric") trunk roll downhill and reduced uphill knee flexion velocity. Subsequent arm abduction partially corrected the lateral instability. Early balance correcting responses in knee and paraspinal muscles showed reduced amplitudes compared with normal responses. Later responses were consistent with compensation mechanisms for the lateral instability created by the stiffened knee and pelvis. We conclude that truncal hypermetria coupled with insufficient uphill knee flexion is the primary cause of lateral instability in SCA patients. Holding the knees and pelvis more rigid possibly permits a reduction in the controlled degrees of freedom and concentration on arm abduction to improve lateral instability. For backwards perturbations excessive posterior COM velocity coincided with marked trunk hypermetric flexion forwards. We concluded that this flexion and the ensuing backwards shift of the pelvis result from rigidity which jeopardizes posterior stability. Timing considerations and the lack of confirmatory changes in amplitudes of EMG activity suggest that lateral and posterior instability in SCA is primarily a biomechanical response to pelvis and knee rigidity resulting from increased muscle background activity rather than changed evoked responses.

CSF studies facilitate DNA diagnosis in familial Alzheimer's disease due to a presenilin-1 mutation.

In sporadic Alzheimer's disease (AD), cerebrospinal fluid (CSF) analysis is becoming increasingly relevant to establish an early diagnosis. We present a case of familial AD due to a presenilin-1 mutation in which CSF studies suggested appropriate DNA diagnostics. A 38 year old Dutch man presented with dementia, spastic paraparesis, and frontal executive function impairments, mimicking familial Creutzfeldt Jakob disease and frontotemporal dementia. CSF studies, revealing increased total tau and phosphorylated-tau levels with decreased amyloid-beta42, distinguished familial AD from Creutzfeldt Jakob disease and frontotemporal dementia. A causative p.L424R PSEN1 mutation was subsequently identified.

The fork in the road: HIV as a potential positive turning point and the role of spirituality.

We interviewed 147 HIV-positive people regarding their key life-changing experiences - involving profound changes in attitudes, behaviors, beliefs (including spiritual beliefs), or self-views - to determine the prominence of HIV as the key positive/negative turning point. HIV was the key turning point, for 37% (26% positive, 11% negative), whereas for 63% of our sample it was not. Characteristics associated with perceiving HIV as the most positive turning point included having a near-death experience from HIV, increasing spirituality after HIV diagnosis, and feeling chosen by a Higher Powerto have HIV. Notably, perceived antecedents of viewing HIV as the key positive turning point were hitting rock bottom and calling on a Higher Power. Conversely, viewing HIV as the most negative turning point was associated with declining spirituality after diagnosis. Spirituality can both negatively and positively affect coping with HIV. Promoting positive spiritual coping may offer new counseling approaches. Further, for the majority of the participants, HIV is not the key turning point, which may be an indicator of the normalization of HIV with the advent of effective treatment.

Flat threshold and mid-frequency hearing impairment in a Dutch DFNA8/12 family with a novel mutation in TECTA. Some evidence for protection of the inner ear.

A novel TECTA mutation (c.5331G>A) was identified affecting alpha-tectorin just N-terminally of the zona pellucida domain in a Dutch family with nonsyndromic autosomal dominant sensorineural hearing impairment. The present mutation is clearly associated with a flat-threshold type of hearing impairment. Intriguingly, our results demonstrated that the present TECTA mutation had a significant protective effect against presbyacusis. Substantial protection against presbyacusis is a novel finding in a family with autosomal dominant hearing impairment.

HIV or HIV-therapy? Causal attributions of symptoms and their impact on treatment decisions among women and men with HIV.

OBJECTIVES: Among people with HIV, we examined symptom attribution to HIV or HIV-therapy, awareness of potential side effects and discontinuation of treatment, as well as sex/gender differences. METHODS: HIV-patients (N=168, 46% female) completed a comprehensive symptom checklist (attributing each endorsed symptom to HIV, HIV-therapy, or other causes), reported reasons for treatment discontinuations and potential ART-related laboratory abnormalities. RESULTS: Main symptom areas were fatigue/sleep/energy, depression/mood, lipodystrophy, and gastrointestinal, dermatological, and neurological problems. Top HIV-attributed symptoms were lack of stamina/energy in both genders, night sweats, depression, mood swings in women; and fatigue, lethargy, difficulties concentrating in men. Women attributed symptoms less frequently to HIV than men, particularly fatigue (p<.01). Top treatment-attributed symptoms were lipodystrophy and gastrointestinal problems in both genders. Symptom attribution to HIV-therapy did not differ between genders. Over the past six months, 22% switched/interrupted ART due to side effects. In women, side effect-related treatment decisions were more complex, involving more side effects and substances. Remarkably, women took predominantly protease inhibitor-sparing regimens (p=.05). Both genders reported only 15% of potential ART-related laboratory abnormalities but more than 50% had laboratory abnormalities. Notably, women had fewer elevated renal parameters (p<.01). CONCLUSIONS: Men may attribute symptoms more often to HIV and maintain a treatment-regimen despite side effects, whereas women may be more prudent in avoiding treatment side effects. Lacking awareness of laboratory abnormalities in both genders potentially indicates gaps in physician-patient communication. Gender differences in causal attributions of symptoms/side effects may influence treatment decisions.

A clinical diagnostic algorithm for early onset cerebellar ataxia.

Early onset cerebellar Ataxia (EOAc) comprises a large group of rare heterogeneous disorders. Determination of the underlying etiology can be difficult given the broad differential diagnosis and the complexity of the genotype-phenotype relationships. This may change the diagnostic work-up into a time-consuming, costly and not always rewarding task. In this overview, the Childhood Ataxia and Cerebellar Group of the European Pediatric Neurology Society (CACG-EPNS) presents a diagnostic algorithm for EOAc patients. In seven consecutive steps, the algorithm leads the clinician through the diagnostic process, including EOA identification, application of the Inventory of Non-Ataxic Signs (INAS), consideration of the family history, neuro-imaging, laboratory investigations, genetic testing by array CGH and Next Generation Sequencing (NGS). In children with EOAc, this algorithm is intended to contribute to the diagnostic process and to allow uniform data entry in EOAc databases.