Characterization of atypical Erwinia carotovora strains causing blackleg of potato in Brazil

AIMS

To determine the characteristics of bacteria associated with the blackleg disease of potato in Brazil and compare them with species and subspecies of pectolytic Erwinia.

METHODS AND RESULTS

Biochemical and physiological characteristics of 16 strains from blackleg-infected potatoes in State of Rio Grande do Sul, Brazil, were determined and differentiated them from all the E. carotovora subspecies and E. chrysanthemi. Pathogenicity and maceration ability of the Brazilian strains were greater than those of E. carotovora subsp. atroseptica, the causal agent of potato blackleg in temperate zones. Analyses of serological reaction and fatty acid composition confirmed that the Brazilian strains differed from E. carotovora subsp. atroseptica, but the sequence of 16S rDNA gene and the 16S-23S intergenic spacer (IGS) region confirmed the Brazilian strains as pectolytic Erwinia. Restriction analysis of the IGS region differentiated the Brazilian strains from the subspecies of E. carotovora and from E. chrysanthemi. A unique SexAI restriction site in the IGS region was used as the basis for a primer to specifically amplify DNA from the Brazilian potato blackleg bacterium in PCR.

CONCLUSIONS

The bacterium that causes the blackleg disease of potato in Brazil differs from E. carotovora subsp. atroseptica, the blackleg pathogen in temperate zones. It also differs from other subspecies of E. carotovora and from E. chrysanthemi and warrants status as a new subspecies, which would be appropriately named E. carotovora subsp. brasiliensis.

SIGNIFICANCE AND IMPACT OF THE STUDY

The blackleg disease of potato is caused by a different strain of pectolytic Erwinia in Brazil than in temperate potato-growing regions. The Brazilian strain is more virulent than E. carotovora subsp. atroseptica, the usual causal agent of potato blackleg.

Insertion of dGMP and dAMP during in vitro DNA synthesis opposite an oxidized form of 7,8-dihydro-8-oxoguanine

Oxidative damage to DNA bases commonly resultsin the formation of oxidized purines, particularly 7,8-dihydro-8-oxoguanine (8-oxoG) and 7,8-dihydro-8-oxoadenine (8-oxoA), the former being a well-known mutagenic lesion. Since 8-oxoG is readily subject to further oxidation compared with normal bases, the insertion of a base during DNA synthesis opposite an oxidized form of 8-oxoG was investigated in vitro. A synthetic template containing a single 8-oxoG lesion was first treated with different one-electron oxidants or under singlet oxygen conditions and then subjected to primer extension catalyzed by Klenow fragment exo- (Kf exo-), calf thymus DNA polymerase alpha (pol alpha) or human DNA polymerase beta (pol beta). Consistent with previous reports, dAMP and dCMP are inserted selectively opposite 8-oxoG with all three DNA polymerases. Interestingly, oxidation of 8-oxoG was found to induce dAMP and dGMP insertion opposite the lesion by Kf exo- with transient inhibition of primer extension occurring at the site of the modified base. Furthermore, the lesion constitutes a block during DNA synthesis by pol alpha and pol beta. Experiments with an 8-oxoA-modified template oligonucleotide show that both 8-oxoA and an oxidized form of 8-oxoA direct insertion of dTMP by Kf exo-. Mass spectrometric analysis of 8-oxoG-containing oligonucleotides before and after oxidation with IrCl62-are consistent with oxidation of primarily the 8-oxoG site, resulting in formation of a guanidinohydantoin moiety as the major product. No evidence for formation of abasic sites was obtained. These results demonstrate that an oxidized form of 8-oxoG, possibly guanidinohydantoin, may direct misreading and misinsertion of dNTPs during DNA synthesis. If such a process occurred in vivo, it would represent a point mutagenic lesion leading to G-->T and G-->C transversions. However, the corresponding oxidized form of 8-oxoA primarily shows correct insertion of T during DNA synthesis with Kf exo-.

Structural characterization of the active form of PerR: insights into the metal-induced activation of PerR and Fur proteins for DNA binding

In Bacillus subtilis, the transcription factor PerR is an iron dependant sensor of H(2)O(2). The sensing mechanism relies on a selective metal catalysed oxidation of two histidine residues of the regulatory site. Here we present the first crystal structure of the active PerR protein in complex with a Mn(2+) ion. In addition, X-ray absorption spectroscopy experiments were performed to characterize the corresponding iron form of the protein. Both studies reveal a penta-coordinate arrangement of the regulatory site that involves three histidines and two aspartates. One of the histidine ligand belongs to the N-terminal domain. Binding of this residue to the regulatory metal allows the protein to adopt a caliper-like conformation suited to DNA binding. Since this histidine is conserved in all PerR and a vast majority of Fur proteins, it is likely that the allosteric switch induced by the regulatory metal is general for this family of metalloregulators.

In vitro DNA synthesis opposite oxazolone and repair of this DNA damage using modified oligonucleotides

Emphasis was placed in this work on the assessment of biological features of 2,2,4-triaminooxazolone, a major one-electron and(. )OH-mediated oxidation product of guanine. For this purpose, two oligonucleotides that contain a unique oxazolone residue were synthesized. Herein we report the mutagenic potential of oxazolone during in vitro DNA synthesis and its behavior towards DNA repair enzymes. Nucleotide insertion opposite oxazolone, catalyzed by Klenow fragment exo(-)and Taq polymerase indicates that the oxazolone lesion induces mainly dAMP insertion. This suggests that the formation of oxazolone in DNA may lead to G-->T transversions. On the other hand, oxazolone represents a blocking lesion when DNA synthesis is performed with DNA polymerase beta. Interestingly, DNA repair experiments carried out with formamidopyrimidine DNA N -glycosylase (Fpg) and endonuclease III (endo III) show that oxazolone is a substrate for both enzymes. Values of k (cat)/ K (m)for the Fpg-mediated removal of oxidative guanine lesions revealed that 8-oxo-7,8-dihydroguanine is only a slightly better substrate than oxazolone. In the case of endo III-mediated cleavage of modified bases, the present results suggest that oxazolone is a better substrate than 5-OHC, an oxidized pyrimidine base. Finally, MALDI-TOF-MS analysis of the DNA fragments released upon digestion of an oxazolone-containing oligonucleotide by Fpg gave insights into the enzymatic mechanism of oligonucleotide cleavage.

Oxidative base damage to DNA: specificity of base excision repair enzymes

Base excision repair (BER) is likely to be the main mechanism involved in the enzymatic restoration of oxidative base lesions within the DNA of both prokaryotic and eukaryotic cells. Emphasis was placed in early studies on the determination of the ability of several bacterial DNA N-glycosylases, including Escherichia coli endonuclease III (endo III) and formamidopyrimidine DNA N-glycosylase (Fpg), to recognize and excise several oxidized pyrimidine and purine bases. More recently, the availability of related DNA repair enzymes from yeast and human has provided new insights into the enzymatic removal of several.OH-mediated modified DNA bases. However, it should be noted that most of the earlier studies have involved globally modified DNA as the substrates. This explains, at least partly, why there is a paucity of accurate kinetic data on the excision rate of most of the modified bases. Interestingly, several oxidized pyrimidine and purine nucleosides have been recently inserted into defined sequence oligonucleotides. The use of the latter substrates, together with overexpressed DNA N-glycosylases, allows detailed studies on the efficiency of the enzymatic release of the modified bases. This was facilitated by the development of accurate chromatographic and mass spectrometric methods aimed at measuring oxidized bases and nucleosides. As one of the main conclusions, it appears that the specificity of both endo III and Fpg proteins is much broader than expected a few years ago.

Gel electrophoretic detection of 7,8-dihydro-8-oxoguanine and 7, 8-dihydro-8-oxoadenine via oxidation by Ir (IV)

Two gel electrophoretic methods are described for detection of 7, 8-dihydro-8-oxoguanine and 7,8-dihydro-8-oxoadenine based on their further oxidation with one-electron oxidants including IrCl62-and IrBr62-. The products of nucleobase oxidation lead to enhanced piperidine-sensitive cleavage and to highly visible stop points in a primer extension assay. 8-oxoG and 8-oxoA lesions may be distinguished by the latter's inability to be oxidized by IrBr62-compared to IrCl62-Comparison is also made to oxidation by MnO4-.

Repair and mutagenic potential of oxaluric acid, a major product of singlet oxygen-mediated oxidation of 8-oxo-7,8-dihydroguanine

Oxidative reactions within DNA commonly result in base modifications. Among the four DNA bases, guanine is the most susceptible to various oxidants, and its related oxidized form, 8-oxo-7,8-dihydroguanine, has been extensively studied in terms of repair and mutagenicity. However, 8-oxo-7,8-dihydroguanine is readily subjected to further oxidation, and this has become a point of interest. We recently found that singlet oxygen oxidation of 8-oxo-7,8-dihydroguanine led to the predominant formation of oxaluric acid as the final product. We report herein on the biological features of oxaluric acid dealing with in vitro DNA synthesis and its removal from DNA by repair enzymes. Nucleotide insertion opposite oxaluric acid, catalyzed by Kf exo(-) and Taq indicates, that oxaluric acid induces G to T and G to C transversions. On the other hand, oxaluric acid represents a block when synthesis is performed with pol beta. Interestingly, DNA repair experiments carried out with formamidopyrimidine DNA N-glycosylase (Fpg) and endonuclease III (endo III) show that oxaluric acid is a substrate for both enzymes. Values of k(cat)/K(m) for the Fpg-mediated removal of oxidative guanine lesions revealed that 8-oxoGua is only a slightly better substrate than oxaluric acid. Interestingly, the results obtained with endo III suggest that oxaluric acid is a much better substrate than is 5-hydroxycytosine (5-OHC), an oxidized pyrimidine base.

Repair and replication of oxidized DNA bases using modified oligodeoxyribonucleotides

Modified oligodeoxyribonucleotides (ODNs) are powerful tools to assess the biological significance of oxidized lesions to DNA. For this purpose, we developed original synthetical pathways for the site-specific insertion of several oxidized bases into DNA fragments. Thus, the chemical solid-phase synthesis of ODNs using original strategies of protection and mild conditions of deprotection, as well as a specific post-oxidation approach of an unique nucleoside residue within the sequence have been applied. These two approaches of preparation allowed us to have access to a set of modified ODNs that contain a single modified nucleoside, i.e., N-(2-deoxy-beta-D-erythro-pentofuranosyl)formylamine (dF), 5-hydroxy-2'-deoxycytidine (5-OHdCyd), thymidine glycol (dTg), 5,6-dihydrothymidine (DHdThd), 2,2-diamino-4-[(2-deoxy-beta-D-erythro-pentofuranosyl)-amino]-5(2H)- oxazolone (dZ), N-(2-deoxy-beta-D-erythro-pentofuranosyl)cyanuric acid (dY), 5',8-cyclo-2'-deoxyguanosine (cyclodGuo) and 5',8-cyclo-2'-deoxyadenosine (cyclodAdo). The substrates were used to investigate recognition and removal of the lesions by bacterial DNA N-glycosylases, including endonuclease III (endo III) and Fapy glycosylase (Fpg). In addition, the DNA polymerase-mediated nucleotide incorporation opposite the damage was determined using modified ODNs as templates.

Immunephenotype of glomerular and interstitial infiltrating cells in protocol renal allograft biopsies and histological diagnosis

Patients with a protocol renal allograft biopsy simultaneously displaying interstitial fibrosis/tubular atrophy (IF/TA) and subclinical rejection (SCR) have a shortened graft survival than patients with a normal biopsy, or with a biopsy only displaying IF/TA or SCR. The poor outcome of these patients could be related with a more severe inflammation. We evaluate the immunophenotype of infiltrating cells in these diagnostic categories. Nonexhausted paraffin blocks from protocol biopsies done during the first year were stained with anti-CD45, CD3, CD20, CD68 and CD15 monoclonal antibodies. Glomerular and interstitial positive cells were counted. C4d deposition in peritubular capillaries was evaluated. Histological diagnoses were: normal (n = 80), SCR (n = 17), IF/TA (n = 42) and IF/TA + SCR (n = 17). Only interstitial CD20 positive cells were significantly increased in patients displaying IF/TA + SCR; normal (137 +/- 117), SCR (202 +/- 145), IF/TA (208 +/- 151) and IF/TA + SCR (307 +/- 180 cells/mm(2)), p < 0.01. The proportion of biopsies displaying C4d deposition was not different among groups. The upper tertile of CD20 positive interstitial cells was associated with a decreased death-censored graft survival (relative risk: 3.01, 95% confidence interval: 1.23-7.35; p = 0.015). These data suggest that B-cell interstitial infiltrates are associated with histological damage and outcome, but do not distinguish whether these infiltrates were the cause or the consequence of chronic tubulo-interstitial damage.

Donor Structural and Functional Parameters Are Independent Predictors of Renal Function at 3 Months

INTRODUCTION

Epidemiological studies have shown that demographic, clinical, and histological donor characteristics influence renal function after transplantation, but whether these variables are independent predictors has not been established. The aim of this study was to evaluate the relative contribution of different donor variables on glomerular filtration rates (GFRs) at 3 months.

PATIENTS AND METHODS

We analyzed single renal transplants performed at our center from January 2000 to July 2004. Donor variables included age, gender, weight and height, cause of death, duration of brain death, serum creatinine at admission and preprocurement, history of arterial hypertension or diabetes mellitus, and smoking habit. Donor chronic damage score was calculated in preimplantation biopsies as was the addition of interstitial fibrosis, fibrous intimal thickening, and glomerulosclerosis (<10% = 0, >10% = 1). Donor and recipient GFRs were calculated according to the Cockroft-Gault formula.

RESULTS

We analyzed 202 transplants obtained from 113 deceased donors. A renal biopsy was available in 111 transplants. Recipient GFR at 3 months correlated negatively with donor age (R = -0.32, P < .01) and donor chronic damage score (R = 0.32, P < .01). GFR was lower among recipients of female versus male donors (50 +/- 15 vs 60 +/- 20 mL/min; P < .01). Donor cerebrovascular accident death (53 +/- 19 vs 63 +/- 19 mL/min; P < .01) and hypertension (48 +/- 16 vs 59 +/- 20 mL/min; P < .01) were also associated with lower GFR at 3 months. There was a positive correlation between GFR at admission, GFR preprocurement, and GFR at 3 months (R = 0.32 and R = 0.18 respectively; P < .01). Stepwise regression analysis included chronic damage score, GFR at admission, and donor gender but not donor age as independent predictors of GFR at 3 months (R = 0.50; P < .01).

CONCLUSION

Donor structural and functional parameters are independent predictors of renal function at 3 months.

First Report of a Group 16SrIII-B Phytoplasma Associated with Decline of China Tree in Brazil

China tree (Melia azedarach L.), originally from Asia, is an exotic deciduous species in Brazil and is used as an ornamental shade tree in the southern region of the country. Since 2005, plants displaying yellowing, little leaves, witches' broom, and decline have been observed in the State of Rio Grande do Sul. In the streets and avenues of the capital city of Porto Alegre, there are approximately 173 tree species and China tree (6.57% of all trees) is among the top 10 (80,000 China trees and most are symptomatic). Plants with those symptoms are very distinctive and have been found also in the cities of Livramento, Rio Grande, Santa Maria, and Vacaria, places located in seashore areas, and along highways everywhere in the state. The high incidence seems to be related to drought during the last few years. These symptoms are typical of a disease identified by yellowing or decline of China tree associated with phytoplasma and previously reported in the neighboring countries of Argentina, Paraguay, and Bolivia (2). To demonstrate the presence of phytoplasma in diseased trees and to confirm its identity, total DNA was extracted from China tree leaf midribs collected from 10 symptomatic and three asymptomatic plants. Nested PCR was performed with the P1/P7 primer pair in the primary PCR to amplify a 1.8-kb fragment encompassing the 16S rRNA gene, the 16S-23S spacer region, and the 5' end of the 23S rRNA gene, while the secondary PCR was primed by the R16F2n/R16R2 primer pair to amplify a 1.2-kb fragment of the 16S rRNA gene from the 1.8-kb fragment (3,4). DNA fragments of 1.2 kb amplified from nested PCR were analyzed by restriction fragment length polymorphism with restriction enzymes AluI, HhaI, HpaII, KpnI, MboI, MseI, and RsaI, revealing identical profiles for each amplicon and demonstrating that a phytoplasma belonging to group 16SrIII, subgroup B (16SrIII-B) (1) was associated consistently with all symptomatic plants. BLAST analysis revealed 99% identity among these cloned 1.2-kb sequences and representative sequences of phytoplasmas affiliated with group 16SrIII (GenBank Accession Nos. AY081817 and AF147706). A majority consensus sequence representing the phytoplasma found in China trees was selected and deposited in GenBank (Accession No. FJ404775). These results were confirmed by observation with transmission electron microscopy of pleomorphic bodies 400 to 2,000 nm in diameter in the phloem sieve tubes of all symptomatic trees. No phytoplasma was detected or visualized in asymptomatic samples. These results corroborate those from studies conducted in neighboring countries that demonstrated the association between phytoplasmas of group 16SrIII and decline of China trees (1). In conclusion, the current study revealed that a phytoplasma affiliated with group 16SrIII-B is associated with the decline of China tree in Brazil, a disease previously described based solely on symptoms (2). The incidence and severity of the disease are enough to prevent further use of these trees as landscape plants in southern Brazil. References: (1) J. D. Arneodo et al. J. Phytopathol. 155:70, 2007. (2) M. Dalbosco et al. Fitopatol. Bras. 30(Suppl.):177, 2005. (3) S. Deng and C. Hiruki. J. Microbiol. Methods 14:53, 1991. (4) C. D. Smart et al. Appl. Environ. Microbiol. 62:2988, 1996.

Trends of maxillofacial trauma: An update from the prospective register of a multicenter study in emergency services of Chile

Background

Determine the behavior of the maxillofacial trauma of adults treated in 3 tertiary care centers in the central zone of Chile.

Material and Methods

Descriptive, cross-sectional, multicenter study, based on the prospective records of maxillofacial trauma cases attended between May 2016 and April 2017 by dental and maxillofacial clinical teams of Adult Emergency Units of hospitals Dr. Sótero del Río (metropolitan region), Carlos Van Buren and Dr. Gustavo Fricke (region V). Age, sex, date of occurrence, type of trauma according to ICD-10, etiology, legal medical prognosis and associated injuries were recorded, stratifying by sex and age. Chi square and unpaired Wilcoxon tests were used to compare by groups.

Results

2.485 cases and 3.285 injuries were investigated. The male: female ratio was 1.7: 1 with age under 30 predominant, followed by older adults. Variability was observed in the yearly, weekly and daily presentation. The highest frequencies were in January and September, weekends and at night. The main etiologies were violence (42.3%), falls (13.1%) and road traffic crashes (12.9%) with differences by age and sex (p<0.05). 31,9% of the injuries occurred in hard tissue, being fractures in nasal bones predominant (S02.2).

Conclusions

The profile of the maxillofacial trauma in Chile seems to be mixed by age, affecting young people and the elderly. The male sex predominates; the main cause, which varies by age group, is violence. Their surveillance is possible from hospital emergency records.

Key words:Maxillofacial trauma, emergency department, multicenter study.

Trade-offs between succulent and non-succulent epiphytes underlie variation in drought tolerance and avoidance

Epiphyte communities comprise important components of many forest ecosystems in terms of biomass and diversity, but little is known regarding trade-offs that underlie diversity and structure in these communities or the impact that microclimate has on epiphyte trait allocation. We measured 22 functional traits in vascular epiphyte communities across six sites that span a microclimatic gradient in a tropical montane cloud forest region in Costa Rica. We quantified traits that relate to carbon and nitrogen allocation, gas exchange, water storage, and drought tolerance. Functional diversity was high in all but the lowest elevation site where drought likely limits the success of certain species with particular trait combinations. For most traits, variation was explained by relationships with other traits, rather than differences in microclimate across sites. Although there were significant differences in microclimate, epiphyte abundance, and diversity, we found substantial overlap in multivariate trait space across five of the sites. We found significant correlations between functional traits, many of which related to water storage (leaf water content, leaf thickness, hydrenchymal thickness), drought tolerance (turgor loss point), and carbon allocation (specific leaf area, leaf dry matter content). This suite of trait correlations suggests that the epiphyte community has evolved functional strategies along with a drought avoidance versus drought tolerance continuum where leaf succulence emerged as a pivotal overall trait.

POS0933 TREATMENT ACCESS AND ADHERENCE DURING SOCIAL PREVENTIVE AND MANDATORY ISOLATION IN ARGENTINIAN PATIENTS WITH SPONDYLARTHRITIS

Background:

Access to high-cost treatments is especially limited in low-resource countries. This issue is becoming stronger today given the health and economic crisis caused by the SARS-CoV2 pandemic. There are no reports in our country on limitations to access and adherence to treatment in patients with Spondyloarthritis (SpA) during social preventive and mandatory isolation.

Objectives:

Evaluate access and adherence to treatment in patients with Spondyloarthritis during social preventive and mandatory isolation.

Methods:

Patients with axial spondyloarthritis (axSpA) radiological (r-axSpA), non-radiological (nr-axSpA) and peripheral spondyloarthritis (pSpA), according to ASAS criteria and psoriatic arthritis (PsA) according to CASPAR criteria, were included. Sociodemographic data, comorbidities, disease activity and treatments were collected at baseline. Data on treatment discontinuation, medical attention for suspected COVID-19 disease, RT-qPCR for SARS-CoV-2 detection and outcome of COVID-19 disease were collected from April to September 2020. Numerical variables were summarized as means and standard deviations (SD) or as medians and interquartiles 25-75 (IQ 25-75).

Results:

320 patients were included, 55% were male, with a mean age of 50 years (SD 13), 21.6% had diagnosis of r-axSpA, 6.9% nr-axSpA, 6.9% pSpA, and 64.7% PsA. Disease duration was 11 (IQ 5-16) years and activity parameters were as follow: BASDAI 3.65 (SD 3), BASFI 3 (1.5-9), PASI 0.3 (0-7), BSA 0.2 (0-6). 14 (4.4%) patients with COVID-19 disease were reported, 10 were confirmed by positive RT-qPCR and 4 by symptoms and history of close contact with SARS patients. 4 (28.6%) received anti TNF (3 adalimumab, 1 certolizumab), 4 (28.6%) anti IL17 (3 secukinumab and 1 ixekizumab), 8 (57%) methotrexate (MTX) and 2 (14%) leflunomide (LF). Among the 320 patients included, 59 (18.4%) discontinued at least one treatment during follow-up. The discontinued medications were: adalimumab (16), MTX (15), secukinumab (9), etanercept (6), certolizumab(4), ustekinumab (3), NSAIDs (2), apremilast (1), golimumab (1), ixekuzumab (1), LF (1), MTX plus LF (1). The main reason for treatment discontinuation was drug shortage: 36 (62%), followed by patient’s decision: 12 (21%) and medical indication: 11 (17%). Of the 36 patients who discontinued due to shortage, 11 received adalimumab, 8 secukinumab, 5 MTX, 3 etanercept, 3 certolizumab, 3 ustekinumab, 2 NSAIDs and 1 golimumab.

Conclusion:

In our Argentinian cohort of patients with SpA, drug shortage was the main reason for treatment discontinuation. The SARS-CoV2 pandemic exposed limitations to access to treatment for patients with SpA.

Disclosure of Interests:

None declared

POS0984 PREVALENCE OF AXIAL SPONDYLOARTHRITIS AMONG YOUNG PEOPLE CONSULTING BECAUSE OF CHRONIC LOW BACK PAIN IN A UNIVERSITY HOSPITAL IN ARGENTINA

Background:

Axial spondyloarthritis (SpA) is an umbrella term encompassing a number of inflammatory conditions involving the axial skeleton. A substantial delay between disease onset, diagnosis and treatment often occurs, related in part to under-recognition of SpA symptoms. Although several studies have investigated since the publication of the ASAS classification criteria in 2009, the prevalence and incidence of axial SpA in the general population and in patients with SpA-related conditions, the actual prevalence of SpA in many countries (including Argentina) is unknown.

Objectives:

To estimate the prevalence of axial SpA and the amount of undiagnosed axial SpA in people under 45 years of age that contacted the health care system for chronic low back pain.

Methods:

The setting was a university hospital-based health management organization with a population distribution similary to that of Buenos Aires. All electronic medical records of patients < 45 years of age at the time of onset of symptoms (as per the ASAS 2009 criteria) and chronic low back pain for 3 or more months) seen at the university hospital-based health management organization between 2009 and 2019, were reviewed. If the patient fulfilled the ASAS criteria, was classified as having axial SpA [ankylosing spondylitis (AS) or non-radiographic axial SpA (nr-axSpA)]. Among this group, if the diagnosis was already established in the medical records by the treating physicians, these patients were also classified as diagnosed with axial SpA; if not, they were classified as undiagnosed with axial SpA. We are reporting the results of descriptive analysis.

Results:

A total of 796 patients were included (Table 1), 426 were women (53.52%, 95% CI 50.1-57) with a median age of 34 years (IQR 29-40) at initiation of low back pain with a median follow up of 77.7 months (IQR 35.7-136.4). The prevalence of axial SpA among patients with chronic low back pain was 5.78% (n= 46, 95% CI 4.2-7.4). 22 patients had AS (2.76%, 95% CI 1.6-3.9) with a median lag time between the onset of low back pain and diagnosis of 58.7 months (IQR 33.5 - 92). All AS cases were already diagnosed. 24 patients had nr-axSpA (3.02%, 95% CI 1.8 - 4.2). Of those, 14 were diagnosed by treating physicians with a lag time median of 23.2 months (IQR 13.1 - 36.5) between the onset of low back pain and diagnosis. Ten patients fulfilled the ASAS criteria (41.7%, CI 95% 22 - 61.4) but were not diagnosed by the treating physicians (22%, 95% CI 9.82-33.66) among the patients with axial SpA.

Table 1.

Demographic, clinical features and therapeutic characteristics of patients with chroniclow back pain stratified by diagnosis

Axial spondyloarthritisN=46Ankylosing spondylitisN=22Diagnosednr-axSpAN=14Undiagnosednr-axSpAN=10OtherdiagnosisN=749Female, n (%, CI)18(39.13%, 25.04-53.23)4(18.18%, 2.06-34.29)10(71.42%,47.76-95.09)4(40%, 9.63-70.36)407(54.34,50.77-57.9)Age at chronic LBP initiation, years, median (IQR)36(29.25-40)32(32-40)38(22-36.75)39(35.25-41.5)34(29-40)Follow up, median months (IQR)88(33.43-148.66)33.67(23.38-90.34)16.73(7.64-24.02)64.77(11.21-164.7)77.69(35.83-135.32)Inflammatory chronic LBP by any criteria n (%)44 (95.7)21 (95.5)13 (92.8)10 (100)56 (7.5, 5.6-9.4)Seen by a Rheumatologist, n (%)42 (91.3)22 (100)14 (100)6 (60)36 (5.1)Lag time between first LBP to SpA diagnosis, months, median (IQR)34.6 (22.6-63.2)58.7 (33.5 – 92)23.1 (13.1-36.5)--bDMARDs treatment n, (%, CI)15(33; 19.5–48)10(45; 24.4–67.8)5(36; 13–64.9)--Lag time between NSAIDs failure and first bDMARDs, months, median (IQR)2.66(2.05-4.63)2.76(2.07-11.3).2.66(2.04-3.25)--

CI: 95% confidential interval, IQR: interquartile range, bDMARDs: biologic disease modifying anti-rheumaticdrugs, LBP: low back pain

Conclusion:

In our cohort, 5.78% of the patients < 45 years with chronic low back pain had axial SpA (AS: 2.76%; and nr-axSpA: 3.02%). Approximately, one in every five patients had undiagnosed axial SpA. Original manuscript made in collaboration with Novartis Argentina S.A

Disclosure of Interests:

Mayra Alejandra Tobar Jaramillo: None declared, Nicolas Marin Zucaro: None declared, Javier Rosa: None declared, Josefina Marin: None declared, Maria Laura Acosta Felquer: None declared, LEANDRO FERREYRA: None declared, JOHN FREDY JARAMILLO GALLEGO: None declared, Josefina Marcos Employee of: Novartis, Vanesa Duarte Employee of: Novartis, Enrique Soriano Speakers bureau: AbbVie, Amber, Bristol-Myers Squibb, Eli Lilly, Novartis, Pfizer Inc, Roche, Consultant of: AbbVie, Eli Lilly, GlaxoSmithKline, Novartis, Pfizer Inc, Sandoz, Grant/research support from: AbbVie, Eli Lilly, GlaxoSmithKline, Novartis, Pfizer Inc, Sandoz.

[Endoscopic sphincterotomy in choledocholithiasis: analysis of an experience of 530 interventions]

We report the experience of 530 consecutive cases of choledocolithiasis treated through Endoscopic Sphincterotomy (ES) between January 1980 and January 1988 (74% of total patients submitted to ES in the same period). 73% had more than 60 years and 47% more than 70 years. A slight majority (52%) had previous cholecystectomy (1/3 still with T-tube drainage) and the remaining had gallbladders insitu (lithiasic in 82%). Therapeutic goals (achieved drainage and complete stone removal) have been achieved in 95% of patients with a low immediate morbidity (9%) and mortality (1%). Delayed mortality, until 30th day (3%) includes 6 cases of obstructive cholangitis with sepsis, unaltered by emergent ES. Follow-up showed a 3% incidence of reintervention from restenosed ES. Patients with lithiasic gallbladder had a 33% cholecistectomy rate, mostly elective during first month post-ES. Our experience confirms ES as an efficient and safe routine treatment for choledocolithiasis. It should be the first choice in patients with previous cholecystectomy or alithiasic gallbladder and a largely applicable tool in those with associated gallbladder stones. Decision about post-ES cholecystectomy in these patients must be weighed on clinical grounds and according to surgical risk groups.