Systematic review: IBD-associated pyoderma gangrenosum in the biologic era, the response to therapy

BACKGROUND

Pyoderma gangrenosum (PG) in inflammatory bowel disease (IBD) is uncommon and therapeutically challenging. Its treatment remains poorly characterised due to limited individual centre or practitioner experience. No large series are reported since 2003, yet IBD treatment has changed substantially.

AIM

To provide an up-to-date review of the published treatment efficacy of currently available therapies for IBD-related PG in the biologic era.

METHODS

Systematic review of cases published post-2003 since the broad availability of anti-tumour necrosis factor-alpha (TNFα) therapy. Cases which did not have coexistent IBD, were non-English language, of paediatric age or without data on response to therapy were excluded.

RESULTS

Sixty cases were identified; 55% female, 50% UC, 45% CD, 5% IBD-U. At PG diagnosis, 58% had active and only 15% inactive IBD, with 27% with IBD activity unspecified. Predominant sites were lower limb (48%) and peristomally (25%); 42% had multiple lesions. In 12%, trauma preceded PG. In 42%, new PG appeared whilst on IBD-specific therapy, whilst 28% were on no therapy and in 30%, IBD therapy was unspecified. Of patients on no therapy at PG onset (n = 17), 16 healed; seven with first- and eight with second-line therapy. In total, 34/60 patients received infliximab, four received adalimumab, two had both; with 33 (92%) responding to one or the other. There was no correlation of PG duration or size with healing times.

CONCLUSIONS

Pyoderma gangrenosum appears predominantly during active IBD and is seen equally in CD and UC. New PG may be a manifestation of recrudescent IBD or it follow trauma. Anti-TNFα therapy as a first-line agent for PG should be considered, as it appears to be highly effective.

Systematic review: body composition in adults with inflammatory bowel disease

BACKGROUND

There is a paucity of data on body composition in patients with inflammatory bowel disease (IBD). Alterations of fat and muscle may affect bone health, muscle performance, quality of life (QoL) and overall morbidity.

AIMS

To systematically review the literature on body composition in adults with IBD, and to discuss potential contributory factors and associations.

METHODS

A systematic search was performed in July 2012 of OVID SP MEDLINE, OVID EMBASE and National Library of Medicine's PubMed Central Medline (Limitations: English, humans, from 1992). A total of 19 articles comparing body composition in patients with IBD with healthy age- and sex-matched control populations were included in the primary analysis.

RESULTS

A total of 631 patients with Crohn's disease (CD) and 295 with ulcerative colitis (UC), mean age 37.1 (s.d. ± 9.2) years; 485 (52%) female, were reported upon. Data were heterogeneous and methodology varied. Compared with controls, a statistically significant reduction in body mass index (BMI) was reported in 37% of CD and 20% of UC patients; reduced fat-free mass in 28% CD and 13% UC patients, and reduced fat mass in 31% CD and 13% UC patients. There was no consistent association between body composition and disease activity, duration, extent or therapies. BMI did not accurately predict body composition.

CONCLUSIONS

Current data, although heterogeneous, suggest that many patients with IBD are affected by aberrations in fat and lean mass, which may not be detected during routine clinical assessment. The prevalence and impact of altered body composition amongst this population warrant further investigation.

Probiotics in luminal gastroenterology: the current state of play

In recent years, there has been a growing interest in the use of probiotics in various areas of gastrointestinal (GI) health. Probiotics are defined as live microorganisms that provide beneficial health effects on the host when administered in adequate amounts. Various probiotics have been shown to suppress bacterial growth, modulate the immune system and improve intestinal barrier function. However, despite several studies with promising results, most trials are small and many have substantial methodological limitations. However, with better targeting and appropriate randomised controlled trials, this area may soon yield important therapeutic strategies to optimise GI health. Here, we review the current knowledge of probiotics of relevance to luminal GI health.

General practitioners' knowledge of and attitudes to inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic disease requiring long-term management. General practitioners (GPs) are often the first point of contact for initial symptoms and flares. Thus we assessed GPs' attitudes to and knowledge of IBD.

METHODS

A state-wide postal survey of GPs was performed collecting demographic details, practice and attitudes in IBD-specific management and knowledge.

RESULTS

Of 1800 GPs surveyed in South Australia, 409 responded; 58% were male, 80% Australian trained and 73% practised in metropolitan areas. Most GPs (92%) reported seeing zero to five IBD patients per month. Overall, 37% of the GPs reported being generally 'uncomfortable' with IBD management. Specifically, they were only somewhat comfortable in providing/using maintenance therapy, steroid therapy or unspecified therapy for an acute flare. They were uncomfortable with the use of immunomodulators and biologicals (71 and 91% respectively). No GP reported never referring, referring sometimes (12%), often (34%) or always (55%). Most (87%) GPs rated their communication with private specialists positively; while only 32% were satisfied with support from public hospitals. Of concern, most (70%) monitored patients on immunosuppression on a case-by-case basis rather than by protocol. In multivariable analyses, GPs' IBD-specific knowledge did not influence comfort with overall management, nor did knowledge influence GP comfort with any particular therapy.

CONCLUSION

Individual GPs care for few IBD patients and have variable attitudes in their practice. Whether improvement can realistically be achieved given individual GP's paucity of patients is questionable. These data support the provision of better support and specific action plans for IBD patients.

Comparison of targeted next-generation sequencing (NGS) and real-time PCR in the detection of EGFR, KRAS, and BRAF mutations on formalin-fixed, paraffin-embedded tumor material of non-small cell lung carcinoma-superiority of NGS

The development of tyrosine kinase inhibitor treatments has made it important to test cancer patients for clinically significant gene mutations that influence the benefit of treatment. Targeted next-generation sequencing (NGS) provides a promising method for diagnostic purposes by enabling the simultaneous detection of multiple mutations in various genes in a single test. The aim of our study was to screen EGFR, KRAS, and BRAF mutations by targeted NGS and commonly used real-time polymerase chain reaction (PCR) methods to evaluate the feasibility of targeted NGS for the detection of the mutations. Furthermore, we aimed to identify potential novel mutations by targeted NGS. We analyzed formalin-fixed, paraffin-embedded (FFPE) tumor tissue specimens from 81 non-small cell lung carcinoma patients. We observed a significant concordance (from 96.3 to 100%) of the EGFR, KRAS, and BRAF mutation detection results between targeted NGS and real-time PCR. Moreover, targeted NGS revealed seven nonsynonymous single-nucleotide variations and one insertion-deletion variation in EGFR not detectable by the real-time PCR methods. The potential clinical significance of these variants requires elucidation in future studies. Our results support the use of targeted NGS in the screening of EGFR, KRAS, and BRAF mutations in FFPE tissue material.

A chronic care model significantly decreases costs and healthcare utilisation in patients with inflammatory bowel disease

INTRODUCTION

Inflammatory bowel disease (IBD) is a chronic condition, yet the model of care is often reactive. We sought to examine whether a formal IBD service (IBDS) reduced inpatient healthcare utilisation or lowered costs for inpatient care.

MATERIAL AND METHODS

With protocols, routine nurse phone follow-up a help-line, more proactive care was delivered, with many symptoms and concerns dealt with prior to routine presentation. Over two five month periods before (2007/8) and after (2009/10) introducing a formal IBDS two discrete cohorts of admitted IBD patients were identified at a single centre. Each patient was assigned five contemporaneously admitted, age and gender matched controls. Inpatient healthcare utilisation was compared between patients and controls and disease-specific factors amongst the two IBD cohorts.

RESULTS

The initial audit captured 102 admitted IBD patients (510 controls, median age 44 years, 57% female); the second audit 95 patients (475 controls, median age 46 years, 45.3% female). In 2009/10, the number of admissions was lower in IBD patients than in controls (mean 1.53+/-1.03 vs. 2.54+/-2.35; p<0.0001). This contrasts with the first audit, where IBD patients had more admissions than controls. Following IBDS introduction, the mean total cost of inpatient care was lower for IBD patients than controls (US$12,857.48 (US$15,236.79) vs. US$ 30,467.78 (US$ 53,760.20), p=0.005). In addition, patients known to a specialist gastroenterologist (GE) and the IBD Service tended to have the lowest mean number of admissions (GE and IBDS 1.14 (+/-0.36) vs. no GE/IBDS 1.64 (+/-1.25)).

CONCLUSIONS

Healthcare utilisation and disease burden in IBD decreased significantly since introducing an IBDS. These data suggest that proactive management improved outcomes. Contact with a gastroenterologist and IBDS seemed to give best results.

A 13-nation population survey of upper gastrointestinal symptoms: prevalence of symptoms and socioeconomic factors

BACKGROUND

Previous data collected in separate studies using various different survey instruments have suggested some variability in the prevalence of symptoms between nations. However, there is a lack of studies which assess and compare the prevalence of upper gastrointestinal symptoms contemporaneously in various countries using a uniform, standardised method.

AIM

To determine the prevalence of upper gastrointestinal (UGI) symptoms in 13 European countries, and the association between socioeconomic factors and symptoms using a standardised method.

METHODS

A representative age- and gender-stratified sample of 23,163 subjects (aged 18-69 years) was surveyed.

RESULTS

The prevalence of UGI symptoms was 38%. UGI symptoms were most prevalent in Hungary [45%, 95% confidence interval (CI): 42.2-48.4] and lowest in the Netherlands (24%, 95% CI: 21.0-26.2). UGI symptoms were more prevalent in women (39%, 95% CI: 38.4-39.6) vs. men (37%, 95% CI: 36.4-37.6). Heartburn (24%, 95% CI: 23.4-24.6) and acidic reflux (14%, 95% CI: 13.6-14.4) were most common. With age, the prevalence of UGI symptoms decreased (e.g. 18-29 years: 43%, 95% CI: 41.4-44.3 vs. 50-69 years: 33%, 95% CI: 32.3-34.4); in contrast, the frequency of symptom episodes/year increased with age (e.g. 18-29 years: 11.3 episodes per years, 95% CI: 10.5-12.1 vs. 50-69 years: 21.8, 95% CI: 20.7-22.9). Socioeconomic status as measured by gross domestic product was inversely associated with symptoms and in total, socioeconomic factors, gender, body mass index, smoking habits and alcohol consumption explained 83% of the variance of UGI symptoms.

CONCLUSIONS

There are marked differences in the country specific prevalence of upper gastrointestinal complaints. Socioeconomic factors are closely associated with the prevalence of upper gastrointestinal symptoms.

Potentially avoidable surgery in inflammatory bowel disease: what proportion of patients come to resection without optimal preoperative therapy? A guidelines-based audit

BACKGROUND

Recently, promulgated inflammatory bowel disease (IBD) guidelines seek to decrease the need for surgery by improving disease control. However, resection rates remain static.

AIMS

We therefore sought to determine the proportion of patients coming to surgery where preoperative management was not optimal according to guidelines.

METHODS

Case notes of all patients with resection surgery for IBD from January 2007 to March 2008 at a metropolitan teaching hospital were retrospectively reviewed. Judgement was made as to whether preoperative management was optimal or suboptimal depending on whether it met guidelines.

RESULTS

A total of 22 subjects with IBD-related resections were identified (15 males and seven females). In total, 17 had Crohn's disease (CD) (11 males) and five ulcerative colitis (UC) (four males). There were 10 smokers (nine CD and one UC). The two most common indications for surgery were inflammatory mass/abscess (n= 8) and refractory to medical therapy (n= 7). While all patients with known IBD (20/22) had seen a gastroenterologist in the past, five known IBD patients had resections undertaken without preoperative gastroenterologist input. Overall preoperative management was judged as optimal in only (9/22) 41%. Of those whose therapy did not meet guidelines (n= 13), five had azathioprine at doses <2 mg/kg, one declined therapy and nine with CD were current smokers.

CONCLUSIONS

Over 50% of IBD resection patients had suboptimal preoperative management, with sub-therapeutic thiopurine dosing and smoking in CD the main problems. Thus, there are significant gains to be made with better use of standard therapies, as it appears that ∼50% of resection surgery was 'potentially avoidable'.

Concentrations of ceftibuten in plasma and the respiratory tract following a single 400 mg oral dose

Concentrations of ceftibuten in bronchial mucosa, epithelial lining fluid (ELF) and alveolar macrophages were determined from samples taken from 15 subjects at bronchoscopy following a single 400 mg oral dose. Concentrations at all sites were determined using a microbiological assay method which was unaffected by the trans-isomer of ceftibuten. The time from dosage to bronchoscopy ranged from 1.4 to 20.3 h and the subjects were analysed in three groups according to time after dosing. Group A had a mean time since dosing of 1.9 h with mean serum, mucosal and ELF concentrations of 15.2 mg/l, 5.7 mg/kg and 1.6 mg/l. Group B had a mean time of 6.5 h after dosing with mean serum, mucosal and ELF concentration of 14.0 mg/l, 3.2 mg/kg and 1.6 mg/l. Group C had a mean time of 13.3 h with mean serum, mucosal and ELF levels of 4.1 mg/l, 1.8 mg/kg and 1.2 mg/l. Macrophage-related ceftibuten could only be detected in two subjects. These levels are related to the minimum inhibitory concentrations of ceftibuten against common respiratory pathogens with the exception of Strep. pneumoniae.

Pregnancy and IBD treatment: this challenging interplay from a patients' perspective

INTRODUCTION

Current data suggest that exacerbations of Inflammatory Bowel Disease (IBD) during pregnancy worsen perinatal outcomes. However, patients' perceptions regarding the interaction between pregnancy and IBD management are unexplored.

AIMS

To (1) obtain pregnancy outcome data from local female IBD patients, and (2) to gain insight into patients' understanding of the interaction between IBD and pregnancy, and how this affects medication-taking behaviour.

METHODS

Female IBD subjects aged 18-50 years were surveyed by questionnaire. This large retrospective study sought patient who reported pregnancy outcomes and examined the relationship between major adverse outcomes, IBD activity and treatment. Subjective data regarding patients' perceptions about IBD management and pregnancy were sought.

RESULTS

219 females were surveyed, 143 completing a questionnaire (68.1%). 342 pregnancies occurred, 298 of which outcome data were available. Overall IBD women reported adverse pregnancy outcome rates comparable to the local population. Major adverse outcomes were more frequent in the subgroup with severe disease during pregnancy (5/14 (35.7%)) than those with inactive disease (14/284 (4.9%)), (OR 6.8 (95% CI 1.7-26.3), p=0.006). Adjusting for disease severity, neither corticosteroid, azathioprine nor 5ASA affected pregnancy outcome. Most female patients (84%) reported (unwarranted) concerns about the effect of IBD medications on pregnancy, free text responses indicating that this was of greater concern than any effect of IBD exacerbation.

CONCLUSIONS

Unwarranted fear of adverse medication effect on pregnancy is highly prevalent in women with IBD, yet awareness of the harmful effect of IBD exacerbation during pregnancy is poor. This information gap between patients and their gastroenterologists warrants attention.

Signatures of mutation and selection in the cancer genome

The cancer genome is moulded by the dual processes of somatic mutation and selection. Homozygous deletions in cancer genomes occur over recessive cancer genes, where they can confer selective growth advantage, and over fragile sites, where they are thought to reflect an increased local rate of DNA breakage. However, most homozygous deletions in cancer genomes are unexplained. Here we identified 2,428 somatic homozygous deletions in 746 cancer cell lines. These overlie 11% of protein-coding genes that, therefore, are not mandatory for survival of human cells. We derived structural signatures that distinguish between homozygous deletions over recessive cancer genes and fragile sites. Application to clusters of unexplained homozygous deletions suggests that many are in regions of inherent fragility, whereas a small subset overlies recessive cancer genes. The results illustrate how structural signatures can be used to distinguish between the influences of mutation and selection in cancer genomes. The extensive copy number, genotyping, sequence and expression data available for this large series of publicly available cancer cell lines renders them informative reagents for future studies of cancer biology and drug discovery.

The pharmacokinetics and tissue penetration of ceftazidime and cefamandole in healthy volunteers

Eight healthy male volunteers received either 1 g of ceftazidime or cefamandole as an intravenous bolus injection. Serial blood samples were taken over the following 8 h. Urine samples were collected over 24 h. Tissue fluid levels of the antibiotics were studied using a cantharides blister technique. Both drugs achieved high serum levels after intravenous injection (ceftazidime 83.3 mg/l, cefamandole 77.7 mg/l at 0.25 h). The serum half-lives were ceftazidime 1.8 h (S.D. 0.22), cefamandole 0.8 h (S.D. 0.07). The mean apparent volume of distribution of ceftazidime was greater than cefamandole (13.6 l compared with 9.8 l, respectively). The total clearance of ceftazidime was 111 ml/min (S.D. 16.6) compared to 216 ml/min (S.D. 30.1) for cefamandole. The maximum concentration of each drug in blister fluid was greater after ceftazidime (44.7 mg/l) than cefamandole (20.2 mg/l). The terminal half-life of ceftazidime in blister fluid (2.1 h) was similar to that in serum but the blister fluid halflife of cefamandole (1.22 h) was slightly prolonged compared with that in serum. suggested that ceftazidime attains levels in this tissue fluid model after a 1 g intravenous dose which might be sufficient to treat infections caused by Staphylococcus aureus, Pseudomonas aeruginosa as well as the common Gram-negatives.

Un-promoted issues in inflammatory bowel disease: opportunities to optimize care

Inflammatory bowel diseases (IBD), comprising Crohn's disease (CD) and ulcerative colitis (UC), are chronic inflammatory disorders of the gut, which lead to significant morbidity and impaired quality of life (QoL) in sufferers, without generally affecting mortality. Despite CD and UC being chronic, life-long illnesses, most medical management is directed at acute flares of disease. Moreover, with more intensive medical therapy and the development of biological therapy, there is a risk that management will become even more narrowly focused on acute care, and be directed only at those with more severe disease, rather than encompassing all sufferers and addressing important non-acute issues. This imbalance of concentration of medical attention on 'high-end' care is in part driven by the need to perform and publish randomized clinical trials of newer therapies to obtain registration and licensing for these agents, which thus occupy a large proportion of the recent IBD treatment literature. This leads to less attention on relatively 'low-technology' issues including: (i) the psychosocial burden of chronic disease, QoL and specific psychological comorbidities; (ii) comorbidity with functional gastrointestinal disorders (FGIDs); (iii) maintenance therapy, monitoring and compliance; (iv) smoking (with regard to CD); (v) sexuality, fertility, family planning and pregnancy; and (vi) iron deficiency and anaemia. We propose these to be the 'Un-promoted Issues' in IBD and review the importance and treatment of each of these in the current management of IBD.

Un-promoted issues in inflammatory bowel disease: opportunities to optimize care

Inflammatory bowel diseases (IBD), comprising Crohn's disease (CD) and ulcerative colitis (UC), are chronic inflammatory disorders of the gut, which lead to significant morbidity and impaired quality of life (QoL) in sufferers, without generally affecting mortality. Despite CD and UC being chronic, life-long illnesses, most medical management is directed at acute flares of disease. Moreover, with more intensive medical therapy and the development of biological therapy, there is a risk that management will become even more narrowly focused on acute care, and be directed only at those with more severe disease, rather than encompassing all sufferers and addressing important non-acute issues. This imbalance of concentration of medical attention on 'high-end' care is in part driven by the need to perform and publish randomized clinical trials of newer therapies to obtain registration and licensing for these agents, which thus occupy a large proportion of the recent IBD treatment literature. This leads to less attention on relatively 'low-technology' issues including: (i) the psychosocial burden of chronic disease, QoL and specific psychological comorbidities; (ii) comorbidity with functional gastrointestinal disorders (FGIDs); (iii) maintenance therapy, monitoring and compliance; (iv) smoking (with regard to CD); (v) sexuality, fertility, family planning and pregnancy; and (vi) iron deficiency and anaemia. We propose these to be the 'Un-promoted Issues' in IBD and review the importance and treatment of each of these in the current management of IBD.

Systematic review: does concurrent therapy with 5-ASA and immunomodulators in inflammatory bowel disease improve outcomes?

BACKGROUND

With greater use of immunomodulators in inflammatory bowel disease (IBD), it is uncertain whether concurrent therapy with both 5-aminosalicylic acid [5-ASA, mesalazine (mesalamine)] and an immunomodulator is necessary.

AIM

To determine whether concurrent therapy with both 5-ASA and immunomodulator(s) improves outcomes in IBD.

METHODS

Systematic review with search terms 'azathioprine, 6-mercaptopurine, thiopurine(s), 5 aminosalicylic acid, mesalazine, inflammatory bowel disease, ulcerative colitis, Crohn's disease, immunosuppressant(s), immunomodulator and methotrexate' in November 2007 to identify clinical trials on concurrent 5-ASA and immunomodulator therapy.

RESULTS

Two small controlled studies were found. Neither showed a benefit on disease control beyond immunomodulator monotherapy. Potential pharmacological interactions exist between 5-ASA and thiopurines. Whilst circumstantial, epidemiological and laboratory evidence suggests that 5-ASA may assist colorectal cancer (CRC) chemoprevention, it may simply be via anti-inflammatory effects. With changes in practice, ethical issues and the long lead-time needed to demonstrate or disprove an effect, no clinical studies can/will directly answer this. The costs of avoiding one CRC in IBD may be as low as 153 times the annual cost of 5-ASA therapy.

CONCLUSIONS

It is unclear whether concurrent 5-ASA and immunomodulator therapy improves outcomes of disease control, drug toxicity or compliance. Concurrent therapy of 5-ASA and immunomodulators may decrease CRC risk at 'acceptable' cost.

The effect of functional gastrointestinal disorders on psychological comorbidity and quality of life in patients with inflammatory bowel disease

BACKGROUND

Symptoms of functional gastrointestinal disorders (FGIDs) are common in patients with inflammatory bowel disease (IBD). Psychological comorbidities of anxiety and depression are also highly prevalent in IBD.

AIM

To quantify the burden of FGIDs in a hospital-based cohort of patients with IBD and to determine whether there is any inter-relationship between the presence and number of FGIDs and patients' quality of life or psychological status.

METHODS

A cross-sectional survey of 61 out-patients was performed. Data on psychological status, quality of life, disease activity and functional symptoms according to Rome III criteria were collected.

RESULTS

Overall, 49 (80%) participants met Rome III criteria for a functional bowel disorder and 52% of participants met criteria for more than one FGID. Participants with no FGID had significantly better physical quality of life than those with more than two FGIDs (P = 0.025). However, there was no relationship among the number of FGIDs, mental quality of life, anxiety or depression.

CONCLUSIONS

Functional gastrointestinal disorders are highly prevalent in out-patients with IBD. Somewhat unexpectedly, the presence of anxiety and/or depression did not appear to correlate with either the presence or the number of FGIDs.

Is esophageal dysphagia in the extreme elderly (>or=80 years) different to dysphagia younger adults? A clinical motility service audit

Dysphagia in elderly patients has major effects on nutrition and quality of life. Although aging itself is associated with changes in esophageal motility, the impact of this on symptoms such as dysphagia is unclear. Data in the extreme elderly are also limited. Symptoms and manometric diagnoses from 23 consecutive older patients (older dysphagia [OD]) >or=80 reporting esophageal dysphagia (12 female, mean age 83 (range 80-93) were compared with those from 23 gender matched younger patients (young dysphagia [YD]) also with dysphagia (mean age 35, range [17-46]). More older patients reported dysphagia as their primary symptom (OD 22/23 vs YD 14/23, P = 0.005). Overall, dysphagia was most common for solids only (OD 16/23 vs YD 15/23) and rare for liquids only (OD 1/23 vs YD 3/23). Dysphagia for both liquids and solids was more frequent in older patients (OD 6/23 vs YD 1/23, P < 0.05). Fewer older patients reported heartburn (OD 3/23 vs YD 14/23, P = 0.001). Manometric diagnoses were generally similar between OD and YD patients with the most common diagnoses being 'nonspecific esophageal motility disorder' (nine each) and 'ineffective peristalsis' (OD = 6, YD = 7). There was a trend for diagnoses related to lower esophageal sphincter failure to be more frequent in younger subjects (OD 1 vs YD 7, P = 0.053). Despite differences in symptom patterns, broad manometric diagnoses in the extreme elderly with dysphagia are similar to younger dysphagia patients. Further studies are required to determine whether this relates to insensitivity in recording or reporting of esophageal manometry (or perceptual differences associated with aging).

Squamous Cell Carcinoma of the Larynx in HIV-Positive Patients: Difficulties in Diagnosis and Management

Patients who are infected with human immunodeficiency virus (HIV) are at increased risk of developing laryngeal squamous cell carcinoma. This malignancy on average appears in a younger age group at a more advanced stage and has a more aggressive course in HIV patients. These patients have difficult management challenges, diagnostically, in staging, and particularly in determining the optimal treatment for each individual patient because their underlying HIV infection can markedly increase morbidity associated with active treatments. They frequently have problems associated with swallowing both before and after treatment. We present two cases that highlight difficulties in the diagnosis and management of these patients as well as post-treatment complications, with particular emphasis on swallowing problems.

Comparative study of the in vitro activity of a new fluoroquinolone, ABT-492

OBJECTIVES

The in vitro activity of a new fluoroquinolone, ABT-492, was determined.

METHODS

MICs were compared with those of two beta-lactams, telithromycin, ciprofloxacin and four later generation fluoroquinolones. The effects of human serum and of inoculum concentration were also investigated.

RESULTS

MIC data indicate that ABT-492 has potent activity against Gram-positive organisms with enhanced anti-staphylococcal activity compared with earlier fluoroquinolones, in addition to activity against beta-haemolytic streptococci, pneumococci including penicillin- and fluoroquinolone-resistant strains and vancomycin-susceptible and -resistant Enterococcus faecalis but not Enterococcus faecium. ABT-492 was the most active agent tested against Haemophilus influenzae, Moraxella catarrhalis, Neisseria meningitidis, fluoroquinolone-susceptible Neisseria gonorrhoeae and anaerobes. Good activity was observed for ABT-492 amongst the Enterobacteriaceae and anaerobes tested, but ciprofloxacin showed superior activity for species of Proteus, Morganella and Providencia, as well as for Pseudomonas spp. In common with the other fluoroquinolones tested, organisms with reduced susceptibility to ciprofloxacin had raised MIC(90)s to ABT-492. The one isolate of H. influenzae tested with reduced fluoroquinolone susceptibility had an ABT-492 MIC close to that of the population lacking a mechanism of quinolone resistance. ABT-492 was more active than ciprofloxacin against Chlamydia spp. An inoculum effect was observed with a number of isolates of Staphylococcus aureus, Streptococcus pneumoniae, E. faecium, Klebsiella spp. and Escherichia coli, in addition to moderately raised MICs in the presence of 70% serum protein. The clinical significance of these findings is yet to be determined.

CONCLUSIONS

ABT-492 is a new fluoroquinolone with excellent activity against both Gram-positive and Gram-negative organisms, with many potential clinical uses.