The Diagnostics and Management of Bronchopulmonary Sequestration: An International Survey among Specialized Caregivers.

BACKGROUND: Our objective was to explore the treatment preferences for bronchopulmonary sequestration (BPS) among an international group of specialized caregivers. METHODS: Sixty-three participants from 17 countries completed an online survey concerning the diagnostics, treatment, and follow-up. Recruitment took place among members of the Collaborative Neonatal Network for the first European Congenital Pulmonary Airway Malformation Trial Consortium and through the Association for European Pediatric and Congenital Cardiology working group database. RESULTS: Most of the 63 participants were pediatric surgeons (52%), followed by pediatric pulmonologists (22%), and pediatric cardiologists (19%). The majority (65%) treated more than five cases per year and 52% standardly discussed treatment in a multidisciplinary team. Half of the participants (52%) based the management on the presence of symptoms, versus 32% on the intralobar or extralobar lesion localization. Centers with both surgical and interventional cardiac/radiological facilities (85%) preferred resection to embolization in symptomatic cases (62 vs. 15%). In asymptomatic cases too, resection was preferred over embolization (38 vs. 9%); 32% preferred noninterventional treatment, while 11% varied in preference. These treatment preferences were significantly different between surgeons and nonsurgeons (p < 0.05). Little agreement was observed in the preferred timing of intervention as also for the duration of follow-up. CONCLUSIONS: This survey demonstrates a variation in management strategies of BPS, reflecting different specialist expertise. Most centers treat only a handful of cases per year and follow-up is not standardized. Therefore, management discussion within a multidisciplinary team is recommended. Recording patient data in an international registry for the comparison of management strategies and outcomes could support the development of future guidelines. LEVEL OF EVIDENCE: Level IV.

Evaluating effects of different control strategies for Infectious Salmon Anaemia (ISA) in marine salmonid farming by scenario simulation using a disease transmission model.

Infectious salmon anaemia (ISA) is an important viral disease causing economic losses and reduced welfare in farmed Atlantic salmon. Here, we present a spatio-temporal stochastic model for the spread of ISA between and within marine aquaculture farms. The model is estimated on historical production data for all marine salmonid farms in Norway from 2004 to February 2019. In this time 142 outbreaks of ISA occurred. We find that transmission from infected neighbouring farms accounts for around 50% of the infections, whereas transmission from "non-specified sources" accounts for around 40%. We hypothesise that the most important of the latter are viruses mutating from the non-virulent ISAV HPR0 to the virulent ISAV HPRdel. The model is used for scenario simulation, or what-if analysis, to investigate the effects of potential strategies to combat ISA, including screening, vaccination and culling. Changing from the current strategy of culling farms with detected ISA-outbreaks to mandatory screening and culling when virus is detected will reduce the fraction of cohorts with a clinical ISA outbreak from 3.8 to 0.36%. Introducing mandatory vaccination would have approximately the same effect as the current stamping-out strategy. The scenario simulation is a useful tool for deciding on appropriate mitigation measures.

The epidemiology of pancreas disease in salmonid aquaculture: a summary of the current state of knowledge.

Pancreas disease (PD) is a viral disease caused by Salmonid alphavirus (SAV) that affects farmed Atlantic salmon (Salmo salar L.) and rainbow trout (Oncorhynchus mykiss (Walbaum)) in the seawater phase. Since its first description in Scotland in 1976, a large number of studies have been conducted relating to the disease itself and to factors contributing to agent spread and disease occurrence. This paper summarizes the currently available, scientific information on the epidemiology of PD and its associated mitigation and control measures. Available literature shows infected farmed salmonids to be the main reservoir of SAV. Transmission between seawater sites occurs mainly passively by water currents or actively through human activity coupled with inadequate biosecurity measures. All available information suggests that the current fallowing procedures are adequate to prevent agent survival within the environment through the fallowing period and thus that a repeated disease outbreak at the same site is due to a new agent introduction. There has been no scientific evaluation of currently used on-site biosecurity measures, and there is limited information on the impact of available mitigation measures and control strategies.

rRNA Operon Copy Number Can Explain the Distinct Epidemiology of Hospital-Associated Methicillin-Resistant Staphylococcus aureus.

The distinct epidemiology of original hospital-associated methicillin-resistant Staphylococcus aureus (HA-MRSA) and early community-associated MRSA (CA-MRSA) is largely unexplained. S. aureus carries either five or six rRNA operon copies. Evidence is provided for a scenario in which MRSA has adapted to the hospital environment by rRNA operon loss (six to five copies) due to antibiotic pressure. Early CA-MRSA, in contrast, results from wild-type methicillin-susceptible S. aureus (MSSA) that acquired mecA without loss of an rRNA operon. Of the HA-MRSA isolates (n = 77), 67.5% had five rRNA operon copies, compared to 23.2% of the CA-MRSA isolates (n = 69) and 7.7% of MSSA isolates (n = 195) (P < 0.001). In addition, 105 MSSA isolates from cystic fibrosis patients were tested, because these patients are repeatedly treated with antibiotics; 32.4% of these isolates had five rRNA operon copies. For all subsets, a correlation between resistance profile and rRNA copy number was found. Furthermore, we showed that in vitro antibiotic pressure may result in rRNA operon copy loss. We also showed that without antibiotic pressure, S. aureus isolates containing six rRNA copies are more fit than isolates with five copies. We conclude that HA-MRSA and cystic fibrosis isolates most likely have adapted to an environment with high antibiotic pressure by the loss of an rRNA operon copy. This loss has facilitated resistance development, which promoted survival in these niches. However, strain fitness decreased, which explains their lack of success in the community. In contrast, CA-MRSA isolates retained six rRNA operon copies, rendering them fitter and thereby able to survive and spread in the community.

Clinical manifestations of pancreas disease outbreaks in Norwegian marine salmon farming - variations due to salmonid alphavirus subtype.

Pancreas disease (PD) in Norwegian salmonid aquaculture has traditionally been caused by salmonid alphavirus (SAV) subtype 3. Following the isolation of a novel SAV subtype in 2010, marine SAV2, two separate endemic areas have developed. It has been debated whether disease outbreaks due to marine SAV2 result in milder clinical manifestations compared to outbreaks caused by SAV3. The aim of this study was to descriptively investigate site-level differences in the clinical manifestations of marine SAV2 and SAV3 at Norwegian seawater sites diagnosed with PD in 2012. The findings suggest that Norwegian PD outbreaks caused by marine SAV2 result in lower mortality and milder clinical signs compared to outbreaks caused by SAV3. For sites without reported PD-related mortality, there was no difference in the mortality levels between sites infected by marine SAV2 and SAV3. The results also indicate that there are no differences in grading quality at slaughter between the SAV subtypes.

Pancreas disease (PD) in sea-reared Atlantic salmon, Salmo salar L., in Norway; a prospective, longitudinal study of disease development and agreement between diagnostic test results.

A prospective longitudinal study was performed on three cages at each of three Norwegian Atlantic salmon seawater sites that experienced outbreaks of pancreas disease (PD). Once salmonid alphavirus (SAV) ribonucleic acid (RNA) was detected by real-time RT-PCR (Rt RT-PCR) at a site, it became detected in all studied cages and was persistently found until the end of the study period up to 19 months after first detection. SAV-specific antibodies were detected at all sites until the end of the study period and were also found at a high prevalence in broodfish at the time of stripping. No evidence of increased viral activity was detected in these broodfish. One site tested negative over several months prior to the first detection of SAV by Rt RT-PCR and SAV-specific antibody, which occurred 1 month prior to clinical manifestations of PD. Moribund fish or thin fish/runts that were sampled after the first PD diagnosis had almost twice the risk of testing positive by one or more diagnostic tests compared to that of randomly selected apparently healthy individuals. This paper describes the first detailed investigation of the disease development of PD at site and cage level in Norway, as well as an assessment of the performance and agreement of the commonly used diagnostic tests.

Salmonid alphavirus (SAV) and pancreas disease (PD) in Atlantic salmon, Salmo salar L., in freshwater and seawater sites in Norway from 2006 to 2008.

A cohort study was initiated in the spring of 2006 to investigate epidemiological aspects and pathogenesis of salmonid alphavirus (SAV) subtype 3 infections and pancreas disease (PD). The aims were to assess involvement of the freshwater production phase, the extent and frequency of subclinical infections and to follow PD-affected populations throughout the entire seawater production cycle, as well as investigate possible risk factors for PD outbreaks. Fish groups from 46 different Atlantic salmon freshwater sites in six counties were sampled once prior to seawater transfer and followed onto their seawater sites. A total of 51 Atlantic salmon seawater sites were included, and fish groups were sampled three times during the seawater production phase. SAV subtype 3 was not identified by real-time RT-PCR from samples collected in the freshwater phase, nor were any SAV-neutralizing antibodies or histopathological changes consistent with PD. In the seawater phase, SAV was detected in samples from 23 of 36 (63.9%) studied sites located within the endemic region. No SAV subtype 3 was detected in samples from seawater sites located outside the endemic region. The cumulative incidence of PD during the production cycle amongst sites with SAV detected was 87% (20 of 23 sites). Average fish weight at time of PD diagnosis ranged from 461 to 5978 g, because of a wide variation in the timing of disease occurrence throughout the production cycle. Mortality levels following a PD diagnosis varied greatly between populations. The mean percentage mortality was 6.9% (+/-7.06) (range 0.7-26.9), while the mean duration of increased mortality following PD diagnosis was 2.8 months (+/-1.11) (range 1-6).

Characterization of Dutch Staphylococcus aureus from bovine mastitis using a Multiple Locus Variable Number Tandem Repeat Analysis.

Current typing methods for Staphylococcus aureus have important drawbacks. We evaluated a Multiple Locus Variable Number Tandem Repeat Analysis (MLVA) scheme with 6 loci which lacks most drawbacks on 85 bovine mastitis isolates from The Netherlands. For each locus the number of repeat units (RU) was calculated. Each combination of repeat units was assigned a MLVA-type (MT). We compared the MLVA typing result with Multi Locus Sequence Typing (MLST), spa-typing and Pulsed-Field Gel Electrophoresis (PFGE). MLVA typing resulted in 18 MTs, although 3 loci could not always be amplified. Spa-typing distinguished 10 spa-types including 3 dominant and 2 new types. PFGE showed 5 dominant profiles with 15 related profiles and 6 unique profiles. MLST showed 4 dominant STs. Some types appeared to be bovine specific. The Simpson's Indices of diversity for PFGE, MLST, spa-typing and MLVA were 0.887, 0.831, 0.69 and 0.781, respectively, indicating that discriminatory power of MLVA was between MLST and spa-typing, whereas PFGE displayed the highest discriminatory power. However, MLVA is fast and cheap when compared to the other methods. The Adjusted Rand index and Wallace's coefficient indicated that MLVA was highly predictive for spa-type, but not vice versa. Analysis of the region neighboring SIRU05 showed a difference in the genetic element bordering the repeats of SIRU05 that explained the negative SIRU05 PCRs. PFGE, MLST, and MLVA are adequate typing methods for bovine-associated S. aureus.

Transmission of methicillin-resistant Staphylococcus aureus strains between different kinds of pig farms.

The main objective of the present study was to investigate if different kinds of pig farms, like farrowing farms and rearing farms, play a role in the transmission of methicillin-resistant Staphylococcus aureus (MRSA) to Dutch finishing farms. Twelve farrowing farms, 11 finishing farms, 6 farrow-to finish farms, 1 rearing farm and 1 centre for artificial insemination were included. Screening of 310 pigs from these 31 farms showed 35 pigs (11%) to carry MRSA in their nares. On 7 of the 31 (23%) investigated farms colonized pigs were found, including 3 finishing farms, 3 farrowing farms and 1 farrow-to-finish farm. The use of standard antimicrobial medication of the pigs seemed to be a risk factor for MRSA carriage. Screening of the pigs on six farms supplying pigs for the MRSA positive farms revealed that the pigs on all but one farm were MRSA positive. Genotyping revealed that all MRSA strains were non-typeable by PFGE using the SmaI restriction enzyme and had multilocus sequence type (MLST) ST398. Different spa-types were found including t011, t108, t567, t899 and t1939, but the spa-types on epidemiologically related farms were identical indicating that MRSA are transmitted between farms through the purchase of colonized pigs. Two SCCmec types were found among the MRSA: type IV and type V. SCCmec type V was predominant. On two farms MRSA isolates with ST398, the same spa-type but with different SCCmec types (IV and V) were found, suggesting that different SCCmec elements have been inserted into MSSA with the same genotype. All MRSA strains were resistant to tetracycline, but additional resistances to erythromycin, lincomycin, kanamycin and gentamicin were also found. All MRSA isolates were negative for the exfoliative toxin genes (eta and etb), PVL toxin genes (lukF and lukS), toxic shock syndrome gene (tst-1), and the leukotoxin genes (lukE, lukD, lukM, lukF').

A novel polymorphism of FcalphaRI (CD89) associated with aggressive periodontitis.

Immunoglobulin A Fc receptor (FcalphaRI) has been implicated in the pathogenesis of periodontitis, because increased IgA responses and FcalphaRI-bearing neutrophils are observed in the disease lesions. Inter-individual differences in susceptibility to periodontitis may be attributable to genetic variability in FcalphaRI-mediated immunity. We here identified an FcalphaRI novel polymorphism (nt 324 A-to-G transition) in the membrane-distal extracellular domain encompassing the ligand-binding site, not resulting in an amino acid change. We compared the FcalphaRI genotype distributions among 46 Japanese aggressive periodontitis (AGP) patients, 80 race-matched healthy controls (HCs), and 59 Caucasian HCs. No ethnic differences were observed in the FcalphaRI genotype distributions between Japanese and Caucasian HC. Notably, we observed a difference in the genotype distribution between the AGP and HC groups. Carriage rate of the nt 324 A allele was higher in the AGP (65.2%) than that in the HC group (42.5%) (odds ratio 2.54). Polymorphonuclear neutrophils from peripheral blood and gingival crevicular fluid exhibited a decreased phagocytosis of periodontopathic bacteria (Porphyromonas gingivalis) in the nt 324 A/A patients as compared with the nt 324 G/G patients. These results document a genetic polymorphism at the FcalphaRI ligand-binding site to be associated with susceptibility to AGP.

Pathogenicity of anti-ganglioside antibodies in the Guillain-Barré syndrome.

Guillain-Barré syndrome (GBS) is a postinfectious inflammatory polyradiculo-neuropathy characterized by flaccid paralysis. Antibodies directed against glycolipid structures (gangliosides), which are highly expressed in the peripheral nervous system, are frequently detected in sera from GBS patients. These antibodies interfere with nerve conduction and have been shown to activate phagocytes via IgG receptors (FcgammaR). These findings support an important role of glycolipid-specific antibodies in the pathogenesis of GBS.

Association of the Fc gamma receptor IIA-R/R131 genotype with myasthenia gravis in Dutch patients.

Myasthenia gravis (MG) susceptibility is partially determined by allelic heterogeneity of immune-modulatory genes. IgG receptors (FcgammaR) link the humoral and cellular branches of the immune system, and regulate immune responses and inflammation. Three FcgammaR subclasses (FcgammaRIIa, FcgammaRIIIa, and FcgammaRIIIb) exhibit functional polymorphisms, which affect efficiency of FcgammaR-mediated functions. FcgammaRIIa genotypes, but not FcgammaRIIIa and FcgammaRIIIb genotypes, were differentially distributed among 107 MG patients as compared to 239 healthy controls (Pz.Lt;0.01), with a relative increase of the FcgammaRIIa-R/R131 genotype (Odds ratio 2.4, 95% confidence interval 1.4-3.9). These data suggest that the FcgammaRIIa-R/R131 genotype is a marker for susceptibility to MG.

Relevance of Fcgamma receptor and interleukin-10 polymorphisms for meningococcal disease.

The contribution of individual Fcgamma receptor (FcgammaR) subclasses to meningococcal phagocytosis was studied. In addition, functional FcgammaR polymorphisms were determined in 50 patients with meningococcal disease (MD), in 183 first-degree relatives of MD patients, and in 239 healthy control subjects, to study the association of FcgammaR genotypes with disease. Efficient internalization of opsonized Neisseria meningitidis serogroup B was mediated via multiple FcgammaR subclasses on phagocytes. Accordingly, a low-efficiency combination of FcgammaRIIa-R/R131, FcgammaRIIIa-F/F158, and FcgammaRIIIb-NA2/2 genotypes was increased significantly in relatives of patients with MD, compared with healthy control subjects (P<.05; odds ratio, 2.6; 95% confidence interval, 1.1-6.3). FcgammaRIIa and FcgammaRIIIa genotype distributions differed between patients with sepsis and those with meningitis. Combined genotypes of FcgammaRIIa and interleukin-10 -1082, which was previously reported as being associated with MD outcome, were distributed randomly in control subjects but not in relatives of patients with MD (P<.01). These data provide further evidence for the association of polymorphic genes on chromosome 1 and MD.

A novel PCR-based method for direct Fc gamma receptor IIIa (CD16) allotyping.

Leukocyte IgG receptors (Fc gamma R) are important immune-response modulating molecules. Fc gamma RIIIa is expressed on macrophages, NK-cells and gamma delta-T cells and exhibits a genetically determined, functional polymorphism at nucleotide 559. This allelic difference predicts either a phenylalanine (F158) or valine (V158) at amino acid 158 in the membrane-proximal extracellular domain, and has been shown to be associated with autoimmune and infectious diseases. Published methods to determine Fc gamma RIIIa genotypes are cumbersome. Therefore, we developed a novel, rapid and reliable PCR-based method to determine Fc gamma RIIIa genotypes. Comparison of genotyping results with direct Fc gamma RIIIa sequencing of 60 blood donors showed 100% accuracy of this new method. Since genotype frequencies of Fc gamma R polymorphisms depend strongly on race and ethnicity, we compared Fc gamma RIIIa genotype frequencies of 176 Caucasian Dutch and 104 Japanese blood donors. Interestingly, these frequencies were not significantly different (P>0.1), in contrast to the Fc gamma RIIa and Fc gamma RIIIb genotype frequencies (P<0.001).

Fcgamma receptor polymorphisms in systemic lupus erythematosus: association with disease and in vivo clearance of immune complexes.

OBJECTIVE: Fc receptors for IgG (FcgammaR) play a prominent role in the clearance of immune complexes in systemic lupus erythematosus (SLE). Polymorphisms of FcgammaR have been proposed as genetic factors that influence susceptibility to SLE. We analyzed 3 functional FcgammaR polymorphisms in a strictly Caucasian population of SLE patients, and determined the influence of these polymorphisms on the clearance of immune complexes in vivo. METHODS: Genomic DNA was isolated from 230 Caucasian patients with SLE and 154 controls. Amplification of FcgammaR-genomic regions in allotype-specific polymerase chain reactions was used to distinguish the genotypes. In addition, we analyzed the FcgammaR genotypes of 13 patients with SLE who participated in a study determining the half-life of IgG-coated erythrocytes in the blood. RESULTS: We found a strong trend toward skewing of FcgammaRIIa, with an enrichment of the homozygous FcgammaRIIa-R/R131 genotype in patients compared with controls. We did not find a correlation between this genotype and the development of lupus nephritis. However, we established that the half-life of IgG-coated erythrocytes in the blood was prolonged in patients expressing the FcgammaRIIa-R/R131 genotype. The homozygous FcgammaRIIIa-F/F158 genotype was found more frequently in patients with arthritis and/or serositis. CONCLUSION: In Caucasian populations, the R/H polymorphism of FcgammaRIIa is a minor determinant in susceptibility to SLE, whereas the V/F polymorphism of FcgammaRIIIa is associated with a set of disease manifestations. Notably, the R/H polymorphism of FcgammaRIIa affects the clearance of immune complexes in vivo, which may influence the course of a disease such as SLE.