Group-specific expressions of co-feeding tolerance in bonobos and chimpanzees preclude dichotomous species generalizations

Bonobos are typically portrayed as more socially tolerant than chimpanzees, yet the current evidence supporting such a species-level categorization is equivocal. Here, we used validated group-level co-feeding assays to systematically test expressions of social tolerance in sixteen groups of zoo- and sanctuary-housed bonobos and chimpanzees. We found that co-feeding tolerance substantially overlaps between the species, thus precluding categorical inference at the species level. Instead, marked differences were observed between groups, with some bonobo communities exhibiting higher social tolerance than chimpanzee communities, and vice versa. Moreover, considerable intergroup variation was found within species living in the same environment, which attests to Pan's behavioral flexibility. Lastly, chimpanzees showed more tolerance in male-skewed communities, whereas bonobos responded less pronounced to sex-ratio variation. We conclude that the pervasive dichotomy between the tolerant bonobo and the belligerent chimpanzee requires quantitative nuance, and that accurate phylogenetic tracing of (human) social behavior warrants estimations of intraspecific group variation.

Chimpanzee Extraversion scores vary with epigenetic modification of dopamine receptor gene D2 (DRD2) and early rearing conditions

Chimpanzees have consistent individual differences in behaviour, also referred to as personality. Similar to human personality structure, five dimensions are commonly found in chimpanzee studies that show evidence for convergent and predictive validity (Dominance, Openness, Extraversion, Agreeableness, and Reactivity/Undependability). These dimensions are to some extent heritable, indicating a genetic component that explains part of the variation in personality scores, but are also influenced by environmental factors, such as the early social rearing background of the individuals. In this study, we investigated the role of epigenetic modification of the dopamine receptor D2 gene (DRD2) as a potential mechanism underlying personality variation in 51 captive chimpanzees. We used previously collected personality trait rating data and determined levels of DRD2 CpG methylation in peripheral blood samples for these same individuals. Results showed that DRD2 methylation is most strongly associated with Extraversion, and that varying methylation levels at specific DRD2 sites are associated with changes in Extraversion in nursery-reared, but not mother-reared, individuals. These results highlight the role of dopaminergic signalling in chimpanzee personality, and indicate that environmental factors, such as social experiences early in life, can have long-lasting behavioural effects, potentially through modification of the epigenome. These findings add to the growing evidence demonstrating the importance of the experience-dependent methylome for the development of complex social traits like personality.

Mapping the contact area of the patellofemoral joint: the relationship between stability and joint congruence

AIMS

The aim of this study was to determine and compare the congruency of the articular surface contact area of the patellofemoral joint (PFJ) during both active and passive movement of the knee with the use of an MRI mapping technique in both the stable and unstable PFJ.

PATIENTS AND METHODS

A prospective case-control MRI imaging study of patients with a history of PFJ instability and a control group of volunteers without knee symptoms was performed. The PFJs were imaged with the use of an MRI scan during both passive and active movement from 0° through to 40° of flexion. The congruency through measurement of the contact surface area was mapped in 5-mm intervals on axial slices. In all, 40 patients were studied. The case group included 31 patients with symptomatic patellofemoral instability and the control group of nine asymptomatic volunteers. The ages were well matched between the case and control groups. The mean age was 25 years (16 to 42; sd 6.9) in the case group and 26 years (19 to 32; sd 5.1) in the control group. There were 19 female and 12 male patients in the case group.

RESULTS

The unstable PFJs were demonstrably less congruent than the stable PFJs throughout the range of knee movement. The greatest mean differences in congruency between unstable and stable PFJ's were observed between 11° and 20° flexion (1.73 cm² vs 4.00 cm²; p < 0.005).

CONCLUSION

The unstable PFJ is less congruent than the stable PFJ throughout the range of knee movement studied. This approach to mapping PFJ congruency produces a measurable outcome and will allow the assessment of pre- and postoperative results following surgical intervention. This may facilitate the design of new procedures for patients with PFJ instability. If a single axial series is to be obtained on MRI scan, the authors recommend 11° to 20° of tibiofemoral flexion, as this was shown to have the greatest difference in contact surface area between the case and control groups. Cite this article: Bone Joint J 2019;101-B:552-558.

Abstract P3-01-21: Circulating tumor cells of breast cancer origin identified by fluorescence in situ hybridization and may be an early predictor of therapy failure in early breast cancer

Background: Most modern methods of detecting circulating tumor cells (CTCs) involve identifying cells with epithelial markers. This approach presents challenges, as not all epithelial cells found in circulation originate from the tumor and not all CTCs express epithelial markers. We propose using a size-exclusion filtration system to enrich for CTCs in peripheral blood followed by fluorescence in situ hybridization (FISH) of the filtered cells to identify cells of tumor origin in the early-stage breast cancer patients. We further hypothesize that the presence of CTCs may be indicators of therapy failure in early-stage breast cancer patients.

Methods: Patients diagnosed with breast cancer (n = 9) were consented for CTC evaluation. Primary tumor DNA was analyzed by the Affymetrix OncoscanTM genome-wide microarray platform and investigated for somatic copy-number alterations (SCNAs). For each patient, two FISH probes were then identified for two regions of gain or a region of gain and a region of loss from the microarray results. Blood samples from patients were obtained before surgery, radiation therapy, endocrine therapy, and at 6-month or 1-year follow-up visits. Blood samples were filtered using ScreenCell® Cyto V2 devices, and FISH was performed. Cells were categorized as normal (diploid for all FISH probes), suspicious (single SCNA detected by FISH), or CTC (two SCNAs detected by FISH). Patients were identified as having CTCs present in their circulation when ≥2 CTCs were observed or when one CTC and &gt;15 suspicious cells were observed.

Results: The microarray data revealed that luminal A tumors ranged from 2-43 SCNAs; luminal B tumors ranged from 15-20 SCNAs; and ER+, PR+, HER2+ tumors ranged from 46-98 SCNAs. Although a correlation appears to exist between tumor genetic complexity and molecular subtype, the degree of complexity was highly varied within each subtype. We found that neither complexity of tumor profile, molecular subtype, nor stage could predict the presence of CTCs in patients.

Molecular SubtypeSCNAsCTCsSuspicious Cells OnlyLuminal A2-433/52/5Luminal B15-200/21/2ER+, PR+, HER2+46-982/20/2

In pre-surgical blood samples, we detected CTCs in 63% of patients with stage 1 disease and in 60% of patients with luminal A tumors, 0% of patients with luminal B tumors, and 100% of patients with triple-positive tumors.

StageCTCsSuspicious Cells OnlyIA/B5/82/8IIA0/11/1

Although limited in number, ongoing investigation revealed that one of our patients in early follow-up with a luminal A, stage IB tumor was identified to have persistent CTCs at 1-year after starting hormonal adjuvant therapy, suggesting residual tumor burden not detected by standard clinical modalities; this finding also suggests that this patient may be at highest risk for relapse and should be considered for additional therapies.

Conclusion: Size-exclusion filtration followed by FISH analysis can accurately identify CTCs in early-stage breast cancer patients. Tumor complexity, molecular subtype, and stage did not predict the presence of CTCs in circulation. Our method for CTC detection may be able to serve as a diagnostic tool for treatment failure.

Citation Format: Liu C, Althof PA, Maroni D, Stevens JM, Grabow CE, VanDyke AZ, Price JD, Sanmann JN, Thayer SP. Circulating tumor cells of breast cancer origin identified by fluorescence in situ hybridization and may be an early predictor of therapy failure in early breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-01-21.

Marine spatial planning makes room for offshore aquaculture in crowded coastal waters

Marine spatial planning (MSP) seeks to reduce conflicts and environmental impacts, and promote sustainable use of marine ecosystems. Existing MSP approaches have successfully determined how to achieve target levels of ocean area for particular uses while minimizing costs and impacts, but they do not provide a framework that derives analytical solutions in order to co-ordinate siting of multiple uses while balancing the effects of planning on each sector in the system. We develop such a framework for guiding offshore aquaculture (bivalve, finfish, and kelp farming) development in relation to existing sectors and environmental concerns (wild-capture fisheries, viewshed quality, benthic pollution, and disease spread) in California, USA. We identify > 250,000 MSP solutions that generate significant seafood supply and billions of dollars in revenue with minimal impacts (often < 1%) on existing sectors and the environment. We filter solutions to identify candidate locations for high-value, low-impact aquaculture development. Finally, we confirm the expectation of substantial value of our framework over conventional planning focused on maximizing individual objectives.

Marine spatial planning is used to co-ordinate multiple ocean uses, and is frequently informed by tradeoffs and composite metrics. Here, Lester et al. introduce an approach that plans for multiple uses simultaneously whilst balancing individual objectives, using a case study of aquaculture development in California.

Relationship quality in captive bonobo groups

We use Principal Component Analyses (PCA) to describe components of social relationship quality in bonobos. We find a three component structure, with the first two components, labelled Value and Compatibility, closely matching the theoretical constructs as well as components reported for chimpanzees and other primates. The third component differed but was abandoned based on Parallel Analysis. Among bonobos, female–female dyads have higher Value and Compatibility. Relationships between males are characterised by low Value and Compatibility. Dyads that had been housed together for a longer time and maternally related ones also have more valuable relationships, while individuals close in rank have low compatibility. The results confirm the strong bonds among female bonobos, but for the first time can describe how they differ qualitatively from close bonds reported for captive chimpanzee females. We suggest future studies should also include Parallel Analysis to more accurately describe the number of components in relationship quality.

Embryos whose polar bodies contain isolated reciprocal chromosome aneuploidy are almost always euploid

STUDY QUESTION

When a chromosome aneuploidy is detected in the first polar body and a reciprocal loss or gain of the same chromosome is detected in the second polar body, is the resulting embryo usually aneuploid for that chromosome?

SUMMARY ANSWER

When reciprocal aneuploidy occurs in polar bodies, the resulting embryo is usually normal for that chromosome, indicating that premature separation of sister chromatids (PSSC)—not non-disjunction—likely occurred in meiosis I.

WHAT IS KNOWN ALREADY

Single-nucleotide polymorphism-based microarray analysis can be used to accurately determine the chromosomal status of polar bodies and embryos. Sometimes, the only abnormality found is a reciprocal gain or loss of one or two chromosomes in the two polar bodies. Prediction of the status of the resulting embryo in these cases is problematic.

STUDY DESIGN, SIZE, DURATION

Blinded microarray analysis of previously diagnosed aneuploid embryos that had reciprocal polar body aneuploidy.

MATERIALS, SETTING, METHODS

IVF cycles were performed between 2008 and 2011 in patients aged 40 ± 3 years (range 35–47 years) with an indication for polar body-based aneuploidy screening. Thirty-five aneuploid vitrified Day 3 embryos were warmed, cultured to Day 5 and biopsied for microarray analysis. Predictions were made for the ploidy status of the embryo if PSSC or non-disjunction had occurred. The signal intensity for the aneuploid chromosome in the first polar body was compared between those that resulted in euploid and aneuploid embryos.

MAIN RESULTS AND THE ROLE OF CHANCE

Among 34 embryos with evaluable results, 31 were euploid on re-analysis. Of 43 chromosomes that had reciprocal aneuploidy in the polar bodies, 41 were disomic in the embryo, indicating that PSSC was likely to have occurred 95% (95% confidence interval 85–99%) of the time. The log 2 ratio signal intensity from the chromosomes that underwent non-disjunction, resulting in unbalanced embryos, were outliers when compared with those that underwent PSSC.

LIMITATIONS, REASONS FOR CAUTION

Although most embryos with reciprocal aneuploid polar bodies were euploid, it is unknown whether they maintain equivalent reproductive potential when transferred. Further study is needed to determine whether these embryos should be re-biopsied and considered for transfer.

WIDER IMPLICATIONS OF THE FINDINGS

This study is consistent with increasing evidence that PSSC is the primary cause of meiosis I errors in embryos from women of advanced reproductive age. Clinicians should be cautious in interpreting results from polar body aneuploidy screening, especially when only the first polar body is tested.

STUDY FUNDING/COMPETING INTEREST(S)

None.

Texture Analysis of Ultrasonic Images of Symptomatic Carotid Plaques can Identify Those Plaques Associated with Ipsilateral Embolic Brain Infarction

OBJECTIVES

The aim of our study was to determine the association between objective, computerised texture analysis of carotid plaque ultrasonic images and embolic CT-brain infarction in patients presenting with hemispheric neurological symptoms.

DESIGN

Cross-sectional study in patients with 50%-99% (ECST) carotid stenosis.

PATIENTS AND METHODS

Carotid plaque ultrasonic images (n=54, 26 with TIAs and 28 with stroke) obtained during carotid ultrasound were normalised and standardised for resolution and subsequently assessed visually for the presence of discrete echogenic or juxtaluminal echolucent components and overall echogenicity (plaque type). Using computer software, 51 histogram/textural features of the plaque outlines were calculated. Factor analysis was subsequently applied to eliminate redundant variables. Small cortical, large cortical and discrete subcortical infarcts on CT-brain scan were considered as being embolic.

RESULTS

Twenty-five cases (46%) had embolic infarcts. On logistic regression, grey-scale median (GSM), a measure of echolucency, spatial grey level dependence matrices (SGLDM) correlation and SGLDM information measure of correlation-1, measures of homogeneity were significant (p<0.05), but not grey level runlength statistics (RUNL) Run Percentage (RP), stenosis severity, type of symptoms or echolucent juxtaluminal components. Using ROC curves methodology, SGLDM information measure of correlation-1 improved the value of GSM in distinguishing embolic from non-embolic CT-brain infarction.

CONCLUSION

Computerised texture analysis of ultrasonic images of symptomatic carotid plaques can identify those that are associated with brain infarction, improving the results achieved by GSM alone. This methodology could be applied to prospective natural history studies of symptomatic patients not operated on or randomised trials of patients undergoing carotid angioplasty and stenting in order to identify high-risk subgroups for cerebral infarction.

Covalent cofactor attachment to proteins: cytochrome c biogenesis

Haem (Fe-protoporphyrin IX) is a cofactor found in a wide variety of proteins. It confers diverse functions, including electron transfer, the binding and sensing of gases, and many types of catalysis. The majority of cofactors are non-covalently attached to proteins. There are, however, some proteins in which the cofactor binds covalently and one of the major protein classes characterized by covalent cofactor attachment is the c-type cytochromes. The characteristic haem-binding mode of c-type cytochromes requires the formation of two covalent bonds between two cysteine residues in the protein and the two vinyl groups of haem. Haem attachment is a complex post-translational process that, in bacteria such as Escherichia coli, occurs in the periplasmic space and involves the participation of many proteins. Unexpectedly, it has been found that the haem chaperone CcmE (cytochrome c maturation), which is an essential intermediate in the process, also binds haem covalently before transferring the haem to apocytochromes. A single covalent bond is involved and occurs between a haem vinyl group and a histidine residue of CcmE. Several in vitro and in vivo studies have provided insight into the function of this protein and into the overall process of cytochrome c biogenesis.

Quantitative MRI measurement of superior cerebellar peduncle in progressive supranuclear palsy

BACKGROUND

Postmortem studies have shown atrophy of the superior cerebellar peduncle (SCP) to distinguish progressive supranuclear palsy (PSP) from other neurodegenerative diseases. It is not clear whether MRI-based measurements can differentiate this relative atrophy of the SCP during life.

METHODS

Volumetric MRI was acquired prospectively in 53 subjects: 19 with PSP, 10 with multiple system atrophy (MSA), 12 with Parkinson disease (PD), and 12 healthy controls. SCP volume was assessed by detailed quantitative volumetric measurement and independently by blinded visual rating of SCP atrophy.

RESULTS

The mean SCP volume, corrected for total intracranial volume, was lower in patients with PSP than controls (p < 0.001), patients with MSA (p = 0.001), and patients with PD (p = 0.003). There was an overlap between individual SCP volume measurements in the PSP subjects and the other groups. Neuroradiologic rating correctly identified PSP cases based on the presence of SCP atrophy with a sensitivity of 74% and a specificity of 94%.

CONCLUSIONS

The authors propose that together with other radiologic features of progressive supranuclear palsy (PSP) such as midbrain atrophy, a visual assessment of the superior cerebellar peduncle may help increase the clinical diagnostic accuracy in PSP.

Mapping the onset and progression of atrophy in familial frontotemporal lobar degeneration

BACKGROUND

Frontotemporal lobar degeneration (FTLD) may be inherited as an autosomal dominant disease. Studying patients "at risk" for developing FTLD can provide insights into the earliest onset and evolution of the disease.

METHOD

We carried out approximately annual clinical, MRI, and neuropsychological assessments on an asymptomatic 51 year old "at risk" family member from a family with FTLD associated with ubiquitin-positive and tau-negative inclusion bodies. We used non-linear (fluid) registration of serial MRI to determine areas undergoing significant regional atrophy at different stages of the disease.

RESULTS

Over the first 26 months of the study, the patient remained asymptomatic, but subsequently developed progressive speech production difficulties, and latterly severe orofacial dyspraxia, dyscalculia, frontal executive impairment, and limb dyspraxia. Regional atrophy was present prior to the onset of symptoms, and was initially centred on the left dorsolateral prefrontal cortex and the left middle frontal gyrus. Latterly, there was increasing asymmetric left frontal and parietal atrophy. Imaging revealed excess and increasing global atrophy throughout the study. Neuropsychological evaluation revealed mild intellectual impairment prior to the onset of these clinical symptoms; frontal executive and left parietal impairment subsequently emerged, culminating in widespread cognitive impairment. Fluid registered MRI allowed the emerging atrophy patterns to be delineated.

CONCLUSION

We have demonstrated the onset and progressive pattern of in vivo atrophy in familial FTLD using fluid registered MRI and correlated this with the clinical features. Fluid registered MRI may be a useful technique in assessing patterns of focal atrophy in vivo and demonstrating the progression of degenerative diseases.

The influence of the steepness of dominance hierarchies on reciprocity and interchange in captive groups of bonobos (Pan paniscus)

Abstract

Biological market models explain variability in reciprocity and interchange between groups. In groups with a shallow dominance gradient, grooming will be mostly exchanged for itself (i.e. exchange will occur). In groups with steep dominance hierarchies, interchange is expected: individuals will groom higher ranking individuals to get access to limited resources or commodities such as support in conflicts, and grooming will be traded for these commodities.We examine patterns of reciprocity in grooming and support, and of interchange of grooming for support or for tolerance in six captive groups of bonobos. We test whether differences between groups in patterns of reciprocity and interchange can be attributed to differences in a measure of steepness of dominance hierarchies, which is based on dyadic agonistic interactions.We found that grooming was reciprocal in some, but not all groups. Support was highly reciprocal, but this was a side effect of dominance in most groups. Interchange between grooming and support was observed in some groups. Corroborating earlier findings, this was a side effect of individuals preferring high ranking individuals as grooming and support partners, possibly because these high-ranking individuals provide more efficient support in conflicts. There was no evidence for interchange of grooming for tolerance.Variability in grooming reciprocity was explained by differences in steepness of dominance hierarchies, as predicted by the biological market models. In groups with a shallow dominance hierarchy, grooming was more reciprocal. This was not true for reciprocity in support. There was some evidence that individuals groomed dominants more frequently in groups with a steep dominance hierarchy. The variation in interchange relations between grooming and support did not depend on the steepness of dominance hierarchies. We suggest that grooming in itself is a valuable commodity in bonobos, especially under captive conditions, which can be exchanged reciprocally. Bonobos may interchange grooming for another value equivalent, with food sharing as a very likely candidate. This interchange effects seem more dependent on potential to monopolise food than on steepness of dominance hierarchies per se.

Pathological substrate for regional distribution of increased atrophy rates in progressive supranuclear palsy

BACKGROUND

Most magnetic resonance imaging (MRI) studies of progressive supranuclear palsy (PSP) are cross-sectional and lack post mortem confirmation of the diagnosis. MRI features described previously in PSP correspond to regions of pathological involvement demonstrated in separate studies, but serial MRI with pathological follow up has not been undertaken.

OBJECTIVE

To investigate whether regions of increased atrophy rates demonstrated in PSP during life using fluid registered serial MRI correspond with pathological findings in confirmed PSP.

METHODS

A 59 year old male presented with a six month history of balance problems and dysarthria. He had a symmetrical, levodopa unresponsive akinetic-rigid syndrome with a vertical supranuclear gaze palsy. A clinical diagnosis of probable PSP was made. His disease progressed relentlessly and he died five years after onset. Two serial MRI scans undertaken during life were reviewed and fluid (non-linear) registration of the images carried out. Post mortem histopathological analysis of the brain was undertaken to definitively confirm the diagnosis and compare regional pathology with the serial imaging.

RESULTS

Fluid registration demonstrated greatest rates of atrophy in the brainstem and frontal cortex, in keeping with the distribution of pathology seen at autopsy.

CONCLUSION

Fluid registration of serial MRI allows the topography and rates of regional atrophy in PSP to be delineated in life. Atrophy patterns correlated well with regional pathological load. These observations suggest that serial MRI with registration may help differentiate PSP from clinically similar conditions and supports its use as a surrogate marker of disease progression.

The regulation of integrin-linked kinase in human platelets: evidence for involvement in the regulation of integrin alpha 2 beta 1

BACKGROUND

Activation of the platelet integrin alpha 2 beta 1 is closely regulated due to the high thrombogenicity of its ligand. As a beta 1 interacting kinase, ILK represents a candidate intracellular regulator of alpha 2 beta 1 in human platelets.

OBJECTIVES

We investigated the regulation of ILK in human platelets and the role of ILK in regulating alpha 2 beta 1 activation in HEL cells, a megakaryocytic cell line.

METHODS

An in-vitro kinase assay was used to determine the effect of platelet agonists on ILK kinase activity together with the contribution of PI3K and PKC on ILK activation. Interaction of ILK with beta 1-integrin subunits was investigated by coimmunoprecipitation and the role of ILK in regulating alpha 2 beta 1 function assessed by overexpression studies in HEL cells.

RESULTS

We report that collagen and thrombin modulate ILK kinase activity in human platelets in an aggregation-independent manner. Furthermore, ILK activity is dually regulated by PI3K and PKC in thrombin-stimulated platelets and regulated by PI3K in collagen-stimulated cells. ILK associates with the beta 1-integrin subunits immunoprecipitated from platelet cell lysates, an association which increased upon collagen stimulation. Overexpression of ILK in HEL cells enhanced alpha 2 beta 1-mediated adhesion whereas overexpression of kinase-dead ILK reduced adhesion, indicating a role for this kinase in the positive regulation of alpha 2 beta 1.

CONCLUSIONS

Our findings that ILK regulates alpha 2 beta 1 in HEL cells, is activated in platelets and associates with beta 1-integrins, raise the possibility that it may play a key role in adhesion events upon agonist stimulation of platelets.

Diagnosis of aspergillus peritonitis in a renal dialysis patient by PCR and galactomannan detection

This report describes the use of the polymerase chain reaction (PCR) and galactomannan detection to detect aspergillus in the continuous ambulatory peritoneal dialysis (CAPD) fluid and blood of a patient with multiple myeloma on CAPD and immunosuppressive treatment. Diagnosis of aspergillosis was initially made by conventional culture of CAPD fluid, but the PCR and galactomannan assays also detected aspergillus DNA and antigen in the blood, respectively. This suggests that the PCR and galactomannan assays, previously suggested as useful in the management of invasive fungal infections in neutropenic haematological patients, may be suitable for application to a broad range of clinical situations and sample types.

The effect of a symptom related "gating policy" on ANCA requests in routine clinical practice

BACKGROUND

Most positive antineutrophil cytoplasmic antibody (ANCA) results are associated with non-vasculitic conditions, and guidelines have been proposed for the judicious use of this test. The outcome of applying similar guidelines in a routine laboratory is reported.

METHODS

All immunology requests (6500) over six months were selected, and those requesting ANCA were studied for the appropriateness of the clinical data supporting the request, the presence of ANCA in those samples tested, and the final diagnosis. Antibodies were detected by indirect immunofluorescence.

RESULTS

ANCA testing was requested in 287 samples. Application of a "gating policy", which refuses analysis on requests that are not supported by clinical data suggestive of systemic vasculitis, made clinicians more selective about the patients for whom they requested ANCA testing. The percentage of "appropriate" screens for systemic vasculitis was relatively high (212 of 287 requests: 72.5%). Only one of the remainder, for whom ANCA testing was initially refused, developed an ANCA related systemic vasculitis in the two years after the study, but the delay in reporting her positive ANCA was only two days. Most of the samples tested were negative (155 of 212), but most (42 of 57) of the patients with positive ANCA results were found to have a systemic vasculitis.

CONCLUSIONS

A gating policy to select requests supported by clinical data suggestive of systemic vasculitis makes ANCA testing more clinically relevant and cost effective. Studies where guidelines can be proposed and their effects measured are important in the light of clinical governance and evidence based medicine.