Photodynamic therapy and combinatory treatments for the control of biofilm-associated infections

The advent of antimicrobial resistance has added considerable impact to infectious diseases both in the number of infections and healthcare costs. Furthermore, the relentless emergence of multidrug-resistant bacteria, particularly in the biofilm state, has made mandatory the discovery of new alternative antimicrobial therapies that are capable to eradicate resistant bacteria and impair the development of new forms of resistance. Amongst the therapeutic strategies for treating biofilms, antimicrobial photodynamic therapy (aPDT) has shown great potential in inactivating several clinically relevant micro-organisms, including antibiotic-resistant 'priority bacteria' declared by the WHO as critical pathogens. Its antimicrobial effect is centred on the basis that harmless low-intensity light stimulates a non-toxic dye named photosensitizer, triggering the production of reactive oxygen species upon photostimulation. In addition, combination therapies of aPDT with other antimicrobial agents (e.g. antibiotics) have also drawn considerable attention, as it is a multi-target strategy. Therefore, the present review highlights the recent advances of aPDT against biofilms, also covering progress on combination therapy.

AB0036 CHILDREN WITH EXTENDED OLIGOARTICULAR AND POLYARTICULAR JUVENILE IDIOPATHIC ARTHRITIS HAVE A CYTOKINE PATTERN FAVOURING B CELL ACTIVATION IN CIRCULATION

Background:

Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease in children. The majority of polyarticular JIA (pJIA) and a large fraction of extended oligoarticular JIA (oJIA) patients fulfil classification criteria for rheumatoid arthritis (RA) in adulthood. B-cells play several important roles in RA pathogenesis, but it is still unclear if the pattern of B-cell involvement in pJIA and extended oJIA follows what has been described for adults with RA.

Objectives:

The main goal of this study was to determine the concentration of cytokines potentially relevant for B-cell activation in serum from children with pJIA and extended oJIA when compared to children with persistent oJIA, adult JIA, early and established RA.

Methods:

Serum samples were collected from children with extended oJIA (n=8), persistent oJIA (n=6), pJIA (n=6), adult JIA (n=8), untreated early RA (<1 year of disease duration, n=12), established RA patients treated with synthetic disease-modifying anti-rheumatic drugs (DMARDs) (n=10) and two groups of age- and sex-matched healthy donors (children, n=6 and adults, n=10). A proliferation-inducing ligand (APRIL), B-cell activating factor (BAFF), interleukin (IL)-6 and IL-21 serum levels were measured by enzyme-linked immunosorbent assay (ELISA).

Results:

Children with extended oJIA, early and established RA patients had significantly higher BAFF serum levels when compared to controls, but no significant differences were observed in children with persistent oJIA, pJIA and adult JIA when compared to all groups included. APRIL serum levels were significantly increased in early and established RA patients when compared to both controls and children with persistent oJIA. No significant differences were found in APRIL concentrations between children with JIA, adult JIA and controls. IL-6 serum levels were significantly increased in children with extended oJIA, pJIA, early and established RA when compared to controls, but no significant differences were found in children with persistent oJIA and adult JIA patients. IL-21 serum levels were significantly increased in early RA when compared to controls, but no significant differences were observed between any of the other groups included.

Conclusion:

The similarity in B-cell cytokine pattern found between extended oJIA, pJIA, early and established RA patients, contrarily to what was observed in persistent oJIA, suggests an early B-cell involvement in the pathogenesis of extended oJIA and pJIA as described for RA.

Disclosure of Interests:

None declared

AB1149 POOR RESPONSE TO HEPATITIS B VACCINATION IN RHEUMATIC PATIENTS TREATED WITH BIOLOGIC THERAPY – IMPLICATIONS FOR CLINICAL PRACTICE

Background:

Hepatitis B virus (HBV) vaccination is recommended for rheumatic patients starting biologic therapy. There is some evidence that HBV vaccination is effective in patients under conventional disease modifying anti-rheumatic drugs (DMARDs), but it is currently unclear whether this also applies to biologics.

Objectives:

To assess the efficacy and safety of HBV vaccination in patients with rheumatic diseases treated with biologics.

Methods:

We included patients with any inflammatory rheumatic diseases treated with any biologic, who were negative for anti-HBs and anti-HBc and had never been vaccinated for HBV. Engerix B® was administered at 0, 1 and 6 months and anti-HBs was re-assessed ≥1 month after last dose. Response was defined as anti-HBs>10IU/L and compared against healthy controls (HC) undergoing Occupational Health immunization. Disease flare was evaluated before and until at least 1 month post-vaccination. We recorded serious adverse events (SAE) and immune-related disorders not previously present.

Results:

We included 67 patients, most treated with TNF inhibitors (TNFi), and 70 HC (Table 1). Most patients were taking concomitant DMARDs (69%) and were in remission/low disease activity (59%). Only 20 patients (30%) had a positive response to vaccination, in comparison to 68 HC (97%, p<0.001). Mean post-vaccination anti-HBs titre was significantly lower in responding patients than HC (569 ± 772 vs 1316 ± 811U/L, p<0.001). Responders diagnoses were RA (n=8 [25%]), PsA (n=7 [39%]), AS (n=4 [33%]) and IBD-associated SpA (n=1[100%]). Response was seen in 19/53 patients treated with TNFi (36%), but only 1/14 (7%) of patients treated with non-TNFi (p=0.037). Importantly, some responders had to temporarily interrupt biologic therapy due to other intercurrences for at least one administration. No clinical or demographic variables were associated with response, including age and disease activity. Fourteen patients (21%) experienced disease flares, of which 7 were mild and did not require therapy adjustment; 3 patients required minor treatment/dose adjustments; 4 patients had secondary failures that led to switches. There were 3 SAE (acute diverticulitis; abdominal infection; atrial fibrillation and urinary infection) 1-4 months after 1st/2nddose, deemed not to be related to vaccination. One RA patient on infliximab had bilateral uveitis 2 months after the 1stvaccine dose, which resolved with topical therapy.

Table 1.

Baseline characteristics of study participants.

Patients (n=67)Controls (n=70)pAge (years)56 ± 946 ± 9<0.001Female (%)40 (60)62 (89)<0.001Diagnosis (%)RA32 (48)PsA / AS18 (27) / 13 (19)Other4 (6)Disease duration (years)17 ± 10Biologic (%)TNF-inhibitor53 (79)Tocilizumab / Abatacept6 (9) / 1 (1)Rituximab / Belimumab2 (3) / 4 (6)Anakinra1 (1)Conventional DMARDs (%)MTX / LEF39 (58) / 1 (1)SSZ / Other6 (9) / 3 (4)None21 (31)Prednisolone (%) / Dose (mg)29 (43) / 5.6 ± 2.1DAS283.1 ± 1.4ASDAS2.2 ± 1.4

Conclusion:

In this study, HBV vaccination response was poor and lower in rheumatic patients treated with biologic therapy than in healthy adults. Vaccination was overall safe but there were 4 severe flares and 3 SAE that lead to treatment switch/interruption, although causal association is difficult to establish. Our data reinforce the recommendation for HBV vaccination prior to starting biologic therapy, possibly even as soon as the diagnosis is established. Alternative HBV vaccination strategies should be investigated in patients already treated with biologics.

Disclosure of Interests:

Vasco C Romão: None declared, Pedro Ávila-Ribeiro Grant/research support from: Novartis, Maria João Gonçalves: None declared, Ana Rita Cruz-Machado: None declared, André Guerreiro: None declared, Vítor Teixeira: None declared, Ana Valido: None declared, Joana Silva-Dinis: None declared, Elsa Vieira-Sousa: None declared, Maria João Saavedra: None declared, Ema Leite: None declared, Rui Tato Marinho: None declared, Joao Eurico Fonseca: None declared

Antibiotic adjuvants from Buxus sempervirens to promote effective treatment of drug-resistant Staphylococcus aureus biofilms

Plants have been long scrutinized in the quest for new antibiotics, but no strong antibiotic molecule was ever found.

Evaluation of the potential of squash pumpkin by-products (seeds and shell) as sources of antioxidant and bioactive compounds

The transformation of byproducts and wastes generated by agro-food companies is of high importance since only a small portion of plant material is utilized directly for human consumption. Squash pumpkin is greatly used in Portugal and as by-products of its processing are generated tons of shell and seeds. In this study we aim to evaluate the potential of these wastes as sources of beneficial and bioactive compounds (antioxidants and antimicrobials), studying the effect of different extraction solvents and drying methods. The samples (fresh and cooked) were freeze-dried and oven-dried followed by extraction with different solvents that revealed the following decreasing order of efficiency: 70 % ethanol, 70 % methanol, 70 % acetone, ultra-pure water and 100 % dichloromethane. The oven-dried samples showed higher values of antioxidant activity and phenolic content, with exception of the values of phenolics for the seeds material. The shell samples presented higher values (1.47 - 70.96 % inhibition) of antioxidant activity and total phenolic content (2.00 - 10.69 mg GAE/g DW). A positive correlation was found between these two parameters on the shell samples, however the squash seeds revealed a negative correlation between the phenolic content and the antioxidant activity. The results show that these industrial agro-food residues are potentially good sources of bioactive compounds with health benefits.

Cortical strut allografting in reconstructive orthopaedic surgery

Many approaches are used in the repair of skeletal defects in reconstructive orthopaedic surgery, and bone grafting is involved in virtually every procedure. Autografting remains the gold standard for replacing bone loss. However, the limited amount of bone that can be harvested and the morbidity associated with that procedure are major constraints to the clinical use of autografts. In contrast, bone allografts can be used in any kind of surgery, whether involving minor defects or major bone loss. Cortical strut allografts unite to host bone through callus formation, restoring bone stock and can be used as an onlay biological plate. These struts can be made from hemicylinders of tibia being fixed to host bone by circumferential metallic cables or by screws. The purpose of this study was to analyze the radiographic outcomes of twelve cryopreserved cortical onlay strut allografts, used in a group of nine patients, for revision hip arthroplasty of the femoral side, to stabilize femoral periprosthetic fractures, to reinforce poor cortical bone and to treat one atrophic femoral nonunion. The average follow-up period was 4.3 years (range, 1.6 to 9 years). No fractures, nonunions or progressive resorption of the bone allografts were observed. All struts were incorporated to the native femur with minimal resorption, within the first year after surgery. There was no failure of any of the allograft reconstructions.The results obtained show that cortical onlay strut allografts, either alone or in conjunction with metallic plate or cancellous bone allografts, are a valuable adjunct for reconstructive surgery of the hip and to treat atrophic femoral nonunion.

BioRePortAP, an electronic clinical record coupled with a database: an example of its use in a single centre

AIMS

To evaluate the efficacy and safety of the treatment of psoriatic arthritis (PsA) patients with tumor necrosis factor (TNF) antagonists in the Rheumatology Department of Hospital de Santa Maria using the BioRePortAP.

METHODS

The Portuguese Society of Rheumatology (SPR) developed an electronic medical chart coupled with a database for the follow up of PsA patients, the BioRePortAP, which was launched in May 2009. This evaluation was based on all the PsA patients that were on active treatment with TNF antagonists in September 2009 and were registered in the BioRePortAP. All the previous data on these patients were introduced in BioRePortAP using the prospective paper based follow up protocol that this Department was using since 1999. Only patients with more than 9 months of treatment were analyzed.

RESULTS

Forty-two patients with PsA, actively treated with anti-TNF agents in September 2009, for at least 9 months, were analyzed in BioRePortAP. Twenty-three patients were male (55%) and nineteen were female (45%). The average age of these patients was 49.8+/-10.9 years old, the average disease duration was of 10.7+/-5.6 years and the mean duration of biological therapy was of 37.8+/-27.8 months. For the 81% of patients with peripheral joint disease there was a mean reduction of more than 80% in the swollen and tender joint counts, and almost 50% in the health assessment questionnaire (HAQ) value. In the 19% of the patients with axial involvement the reduction of BASDAI and BASFI was not statistically significative. On top of that, PASI score suffered a reduction of 64%. Fourteen patients (33.3%) had to switch their TNF antagonist treatment. 58.8% of the switches were due to adverse effects and 41.2% due to therapy failure. Regarding the 56 adverse reactions registered, only one was a severe reaction. The remaining adverse reactions were not severe and 67% of them were due to infections.

DISCUSSION

The results of this first report of the use of the BioRePortAP in clinical practice confirm the efficacy and safety of TNF antagonist treatment in PsA. The results shown here elucidate the potential applications of BioRePortAP as a tool for efficacy and safety assessment of PsA patients treated with biotechnological drugs.

Exuberant calcinosis and acroosteolysis. A diagnostic challenge

A case of exuberant acroosteolysis and subcutaneous tissue calcinosis in the absence of skin involvement is presented. Different hypotheses are discussed following the clinical unfolding of the case in practice.

The antimicrobial effects of glucosinolates and their respective enzymatic hydrolysis products on bacteria isolated from the human intestinal tract

AIMS

The aim of the study was to evaluate the in vitro antibacterial activity of glucosinolates and their enzymatic hydrolysis product against bacteria isolated from the human intestinal tract.

METHODS AND RESULTS

Using a disc diffusion bioassay, different doses of intact glucosinolates and their corresponding hydrolysis products were tested. There were clear structure-activity and concentration differences with respect to the in vitro growth inhibition effects as well as differences in the sensitivities of the individual bacteria. The most effective glucosinolate hydrolysis products were the isothiocyanates; sulforaphane and benzyl isothiocyanate were the best inhibitors of growth. Indole-3-carbinol had some inhibitory effects against the Gram-positive bacteria but had no effect, even at the highest dose, against the Gram-negative bacteria. Indole-3-acetonitrile had some inhibitory activity against the Gram-negative bacteria. Glucosinolates, nitriles and amines were ineffective at all the doses used.

CONCLUSIONS

Glucosinolate hydrolysis products and specifically the isothiocyanates SFN and BITC have significant antimicrobial activity against Gram-positive and Gram-negative bacteria, and might be useful in controlling human pathogens through the diet.

SIGNIFICANCE AND IMPACT OF THE STUDY

This the first major in vitro study demonstrating the potential of these natural dietary chemicals as an alternative to, or in combination with, current antibiotic-based therapies for treating infectious diseases.

Aeromonas aquariorum sp. nov., isolated from aquaria of ornamental fish

During a survey to determine the prevalence of Aeromonas strains in water and skin of imported ornamental fish, 48 strains presumptively identified as Aeromonas were isolated but they could not be identified as members of any previously described Aeromonas species. These strains were subjected to a polyphasic approach including phylogenetic analysis derived from gyrB, rpoD and 16S rRNA gene sequencing, DNA-DNA hybridization, MALDI-TOF MS analysis, genotyping by RAPD and extensive biochemical and antibiotic susceptibility tests in order to determine their taxonomic position. Based on the results of the phylogenetic analyses and DNA-DNA hybridization data, we describe a novel species of the genus Aeromonas, for which the name Aeromonas aquariorum sp. nov. is proposed, with strain MDC47T (=DSM 18362T =CECT 7289T) as the type strain. This is the first Aeromonas species description based on isolations from ornamental fish.

[Hajdu-Cheney Syndrome: a case of acroosteolysis]

Acroosteolysis is a rare clinical manifestation characterized by bone resorption of the terminal phalanges. It can occur in association with the variety of systemic diseases or be idiopathic. The authors describe a case of 47-year-old woman with acroosteolysis of distal phalanges since childhood, congenital amaurosis, premature loss of teeth and mal perforans. Because of the rate and exuberant manifestations found, with no etiological cause identified, the authors diagnosed Hajdu-Cheney Syndrome. Hajdu-Cheney is a rare, autosomal dominant disorder, with sporadic cases, apparently representing new mutations. Based on this case the authors review the differential diagnoses of acroosteolysis and the clinical manifestation of the Hajdu-Cheney syndrome

Updated phylogeny of the genus Aeromonas

Recent phylogenetic studies of the genus Aeromonas based on gyrB and rpoD gene sequences have improved the phylogeny based on 16S rRNA gene sequences first published in 1992, particularly in the ability to split closely related species. These studies did not include the recently described species Aeromonas simiae and Aeromonas molluscorum and only a single strain of Aeromonas culicicola was available for analysis at that time. In the present work, these Aeromonas species and newly isolated strains of A. culicicola were examined. Sequence analysis indicates that A. simiae and A. molluscorum belong to non-described phylogenetic lines of descent within this genus, which supports the original description of both species. The most closely related species are Aeromonas schubertii and Aeromonas encheleia, respectively, which is consistent with 16S rRNA gene sequencing results. However, while the five strains of A. molluscorum showed nucleotide differences in their gyrB and rpoD gene sequences, the only two known A. simiae strains exhibited identical gene sequences, suggesting that they are isolates of the same strain. On the basis of the rpoD gene sequence phylogeny, A. culicicola strains from the original description and new isolates from drinking water and ornamental fish clustered within the species Aeromonas veronii, suggesting inconsistencies with previous results. Other strains with previously controversial taxonomy and new isolates from other studies were included in this study in order to clarify their phylogenetic affiliation at the species level.

Lymphocyte populations in tuberculous pleural effusions

Different systemic and local responses to mycobacterial antigens suggest an active compartmentalization of responsive lymphocytes to tubercular antigens. This fact, observed in pleuritic processes, raises doubts about the accuracy of information obtained in the study of cells taken solely from peripheral blood. For this reason we decided to study the concept of compartmentalization in 140 patients suffering from pleural effusions. Patients were classified into six groups according to the aetiology of the effusion: group I, tuberculous, n = 23; group II, paraneoplastic, n = 41; group III, metapneumonic empyematous, n = 5; group IV, transudate, n = 38; group V, miscellaneous exudate, n = 19; group VI, unknown aetiology, n = 14. In each group we studied the lymphocyte population by using flow cytometry with doubly fluorescent monoclonal antibodies: B [expressing human lymphocyte antigen (HLA)-DR on the surface], T (CD3+), CD4+ and CD8+, and the subpopulation of activated T lymphocytes (together expressing CD3 and HLA-DR on the surface) (CD3+DR+). The study of these subpopulations in peripheral blood did not yield valuable results, but the CD3+DR+ population in pleural fluid demonstrated a diagnostic efficiency of 84% [positive predictive value (PPV) 51%, negative predictive value (NPV) 96%] at a cut-off value of 80.4 cells/mm3. The CD3+DR+ pleural fluid/peripheral blood ratio demonstrated an efficiency of 83% (PPV 50%, NPV 96%), and showed a statistically significant difference (P < 0.02) with regard to all the diagnostic groups, with the exception of the paraneoplastic effusions. The lymphocytic subpopulations study confirms the concept of compartmentalization in tuberculous pleuritis, as shown by the greater number of activated T lymphocytes present in pleural fluid in comparison with peripheral blood in tuberculous pleuritis, a 98% efficiency of adenosine deaminase (ADA) determination in pleural fluid versus a 50% value in peripheral blood, predominance of helper cells (CD4+) in pleural fluid and suppressor cells (CD8+) in peripheral blood, a greater CD4+/CD8+ ratio in pleural fluid than in peripheral blood, and a significant correlation of ADA-CD3+DR+ in pleural fluid, which does not occur in peripheral blood.