The bacillithiol pathway is required for biofilm formation in Staphylococcus aureus

Staphylococcus aureus is a major human pathogen that can cause infections that range from superficial skin and mucosal infections to life threatening disseminated infections. S. aureus can attach to medical devices and host tissues and form biofilms that allow the bacteria to evade the host immune system and provide protection from antimicrobial agents. To counter host-generated oxidative and nitrosative stress mechanisms that are part of the normal host responses to invading pathogens, S. aureus utilizes low molecular weight (LMW) thiols, such as bacillithiol (BSH). Additionally, S. aureus synthesizes its own nitric oxide (NO), which combined with its downstream metabolites may also protect the bacteria against specific host responses. We have previously shown that LMW thiols are required for biofilm formation in Mycobacterium smegmatis and Pseudomonas aeruginosa. Here, we show that the S. aureus bshC mutant strain, which is defective in the last step of the BSH pathway and lacks BSH, is impaired in biofilm formation. We also identify a possible S-nitrosobacillithiol reductase (BSNOR), similar in sequence to an S-nitrosomycothiol reductase found in M. smegmatis and show that the putative S. aureus bsnoR mutant strain has reduced levels of BSH and decreased biofilm formation. Our studies also show that NO plays an important role in biofilm formation and that acidified sodium nitrite severely reduces biofilm thickness. These studies provide insight into the roles of oxidative and nitrosative stress mechanisms on biofilm formation and indicate that BSH and NO are key players in normal biofilm formation in S. aureus.

Gender differences in workplace violence against physicians and nurses in Latin America: a survey from the Interamerican Society of Cardiology

OBJECTIVES

To evaluate gender differences in workplace violence (WPV) against physicians and nurses in Latin America.

STUDY DESIGN

Cross-sectional study.

METHODS

A cross-sectional electronic survey was conducted between January 11 and February 28, 2022. A prespecified gender analysis was performed.

RESULTS

Among the 3056 responses to the electronic survey, 57% were women, 81.6% were physicians, and 18.4% were nurses. At least one act of violence was experienced by 59.2% of respondents, with verbal violence being the most common (97.5%). Women experienced more WPV than men (65.8% vs 50.4%; P < 0.001; odds ratio [OR]: 1.89; 95% confidence interval [CI]: 1.63-2.19). Women were more likely to report at least one episode of WPV per week (19.2% vs 11.9%, P < 0.001), to request for psychological help (14.5% vs 9%, P = 0.001) and to experience more psychosomatic symptoms. In addition, women were more likely to report having considered changing their job after an aggression (57.6% vs 51.3%, P = 0.011) and even leaving their job (33% vs 25.7%, P = 0.001). In a multivariate analysis, being a woman (OR: 1.76), working in emergency departments (OR: 1.99), and with COVID-19 patients (OR: 3.3) were independently associated with more aggressive interactions, while older age (OR: 0.95) and working in a private setting (OR: 0.62) implied lower risk.

CONCLUSIONS

Women are more likely to experience WPV and to report more psychosomatic symptoms after the event. Preventive measures are urgently needed, with a special focus on high-risk groups such as women.

Anal Canal Adenocarcinomas: Prognostic Factors and Outcomes at a Single Institution

PURPOSE/OBJECTIVE(S)

Adenocarcinomas of the anal canal (AAC) represent a rarity among cancers of the digestive tract. Data guiding management is limited to retrospective studies and optimal treatment paradigms of AAC are still evolving. Here, we aim to investigate their prognostic factors and outcomes.

MATERIALS/METHODS

We reviewed anorectal adenocarcinoma patients who underwent curative-intent neo/adjuvant therapy +/- surgery at a single institution from 2015-2019. AAC were defined as tumor epicenters ≤ 2 cm from the dentate line. Our primary outcome was 5-year overall survival (OS). We also analyzed 5-year local recurrence, distant metastasis, and disease-free survival (DFS), defined as the interval after treatment completion to the first occurrence of local, regional, distant recurrence, or death. All tumors were staged according to the Rectal Cancer paradigm per AJCC 7th Staging. Kaplan-Meier and Cox-Proportional Hazards Model were used for survival analyses.

RESULTS

In our cohort, 57 patients met inclusion criteria. Median follow-up time was 54 months. The median age was 64 years; 35% of the cohort was female. The majority of tumors were adenocarcinomas (77%), with a minority of mucinous (12%) and signet ring cell (11%) histologies. The median tumor size was 4 cm, located 1 cm from the anal verge. Most tumors (63%) were grade 2, 77% had T3 disease, and 53% had clinical nodal involvement. Most patients completed neoadjuvant chemoradiation, total mesorectal excision, and adjuvant chemotherapy (54%). Fifty-four percent underwent abdominopelvic resection. Of those who received neoadjuvant therapy, 11% achieved a pathologic complete response. Seventy percent of patients completed chemotherapy, either in the neoadjuvant or adjuvant setting. At 5 years, local recurrence was 9%, regional pelvic recurrence was 12%, inguinal nodal recurrence was 2%, and distant recurrence was 25%. Five-year DFS was 63% and 5-year OS was 70%. Multivariate analysis demonstrated age, female gender, CEA, grade 3 disease, mucinous histology, and nodal involvement to be prognostic of lower OS. Receipt of neo/adjuvant chemotherapy was found to be prognostic of higher OS (HR 0.13, p<0.05).

CONCLUSION

In this cohort, the majority of whom received surgical management, we show numerically similar or higher overall survival in comparison with prior studies. This study is limited by its retrospective nature and sample sizes of an exceedingly rare entity. Receipt of neo/adjuvant chemotherapy appears to have an impact on survival. Further investigation is needed to explore the role of total neoadjuvant therapy in improving outcomes in this patient population.

The Impact of Living with INOCA

Background

There is limited literature available on the impact of myocardial ischemia but no obstructive coronary arteries (INOCA) on patients' lives.

Purpose

We sought to determine how INOCA impacts the physical, social, and mental health of persons with this diagnosis.

Methods

A survey was made available to all members of the patient support group from INOCA International over a 3-month time period. Fitness was estimated using the Duke Activity Status Index (DASI), assessing levels of activities performed prior to the onset of INOCA symptoms, and after the diagnosis of INOCA. The formula to estimate fitness in metabolic equivalents (METs) = 0.43 × DASI + 9.6 / 3.5

Results

A total of 297 patients with INOCA responded to the survey; 91.2% were women. The most common diagnosis was coronary microvascular dysfunction (64.3%) and coronary artery spasm (50.5%) (Table 1). 34.4% reported living with symptoms for ≥3 years before their diagnosis of INOCA was made. 77.8% who had been told their symptoms were not cardiac. The symptoms the respondents experienced were numerous, but 92.9% reported symptoms of chest pain, pressure, or discomfort. Fitness levels prior to the onset of INOCA symptoms were significantly higher compared to after diagnosed with INOCA (8.6±1.8 METs vs 5.6±1.8 METs; P&lt;0.0001). Most respondents reported an adverse impact on their home life (80.5%), social life (80.1%), mental health (70.4%), outlook on life (69.7%), sex life (55.9%), and their partner/spouse relationship (53.9%). Work life was also affected once living with INOCA: approximately three-quarters had reduced their work hours or stopping work completely, 47.5% retired early, and 38.4% applied for disability. While living with INOCA, for each 1-MET decrease in fitness, there was a loss of 3.0±0.6 days/months of physical health, 1.8±0.6 days/month of mental health, and 2.9±0.7 days/months of inability to perform recreational activities (p&lt;0.0001) (Figure 1).

Conclusions

Living with INOCA has significant impact on physical, mental and social health. Significant physical fitness declines are seen in those living with INOCA and are lower in those experiencing any adverse impact of living with INOCA. Additionally, the impact of INOCA on the ability to work has important economic consequences to both the patient and society. Increased recognition of the impact of INOCA on these aspects of health need to be recognized and further work is needed to better diagnosis and treat the symptoms of INOCA to improve the quality of life, cardiovascular outcomes, and overall health of this frequently encountered cardiovascular disorder.

Funding Acknowledgement

Type of funding sources: None.

Mucin O-glycans are natural inhibitors of Candida albicans pathogenicity

Mucins are large gel-forming polymers inside the mucus barrier that inhibit the yeast-to-hyphal transition of Candida albicans, a key virulence trait of this important human fungal pathogen. However, the molecular motifs in mucins that inhibit filamentation remain unclear despite their potential for therapeutic interventions. Here, we determined that mucins display an abundance of virulence-attenuating molecules in the form of mucin O-glycans. We isolated and cataloged >100 mucin O-glycans from three major mucosal surfaces and established that they suppress filamentation and related phenotypes relevant to infection, including surface adhesion, biofilm formation and cross-kingdom competition between C. albicans and the bacterium Pseudomonas aeruginosa. Using synthetic O-glycans, we identified three structures (core 1, core 1 + fucose and core 2 + galactose) that are sufficient to inhibit filamentation with potency comparable to the complex O-glycan pool. Overall, this work identifies mucin O-glycans as host molecules with untapped therapeutic potential to manage fungal pathogens.

AB0980 Hand Osteoarthritis: investigating Pain Effects in a randomised placebo-controlled feasibility study of estrogen-containing therapy (HOPE-e): report on the primary feasibility outcomes

Background

There is an unmet need for new treatments for hand osteoarthritis (OA). Symptomatic hand OA is more common in women and its incidence increases round the age of menopause. Pre-clinical, epidemiological and post hoc studies in Hormone Replacement Therapy (HRT) trials implicate estrogen deficiency as of likely importance in OA aetiopathogenesis. No clinical trials of HRT have been carried out in hand OA to date. The licensed HRT Duavive (conjugated estrogens + SERM bazedoxifene) was selected on its potential for efficacy and tolerability.

Objectives

We set out to determine the feasibility and acceptability of this form of HRT in post-menopausal women with hand OA, to generate proof of concept data and refine methods for a full study.

Methods

ISRCTN12196200. Females aged 40-65 yrs and 1-10yrs after final menstrual period with hand OA fulfilling ACR criteria and 2+ painful hand joints were recruited. Eligibility incorporated best practice for HRT prescription but did not require menopausal symptoms. Recruitment was at 3 sites in primary/secondary care, including directly from the community. Design was parallel group, double-blind 1:1 randomisation of Duavive or placebo, orally once daily for 24 weeks, then weaning for 4 weeks before stopping. Routes and rates of recruitment and the acceptability of randomisation, medication (compliance, retention), and proposed outcomes were measured, and the likelihood of unblinding. Measures related to hand pain and function, menopause symptoms and joint appearance. Patient and Public Involvement actively informed study rationale, design and materials. An end of study questionnaire and 2 participant focus groups provided further acceptability data.

Results

Recruitment was for 12/possible 18 months, interrupted due to COVID-19. Some study procedures were modified to allow reopening whilst collecting all primary outcomes. 434 enquiries/referrals were received, leading to 96 telephone pre-screens, of which 33 gave written informed consent and attended face to face screening. 28/33 screened (85%) were eligible and randomised. The highest number of randomisations was from study web presence (n=7) followed by SMS text from GP surgeries (n=5). Of 401 not proceeding, 250 (62%) were ineligible, most commonly due to contraindicated medication, followed by medical contraindication, whilst 55 (14%) decided not to take part, for reasons including not wanting to take a hormone-based drug or difficulty attending study visits. Retention and compliance were excellent. All 28 participants completed all study follow ups, with only 3 withdrawals from treatment due to AEs, 2 of these at week 24 and all in the placebo arm. There were no serious AEs. High levels of completeness of all study outcome measures were achieved. Bang’s blinding index suggested that participants/investigators were well blinded. There were overall high/good levels of satisfaction with taking part in the study. 26/28 (92%) would recommend taking part to others with hand OA (irrespective of study arm). Many found the flexibility offered by a combination of remote and face to face visits (due to the pandemic) attractive. Additional insights from focus groups were to include hand stiffness as well as pain measures but to reduce the overall number of questions.

Conclusion

Despite COVID-19 and a reduced recruitment period, this study recruited sufficient numbers to assess feasibility outcomes. Randomisation of eligible people and retention rates were high. A mixture of remote and face to face visits due to COVID-19 probably improved recruitment and retention and was supported by participants, who were generally satisfied with the study design and medication. The study provided useful insight and improvements that would be incorporated into a future study. Overall, this feasibility study showed that with clear messaging on eligibility and a defined recruitment strategy, recruitment and retention to a study testing this treatment is possible.

Acknowledgements

This research was funded by the National Institute for Health Research (NIHR) under its Research for Patient Benefit (RfPB) Programme (Grant Reference Number PB-PG-0416-20023). The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care. The study team thank the sites and the participants who made this research possible.

Disclosure of Interests

Jennifer A.E. Williams: None declared, Mae Chester-Jones: None declared, Anne Francis: None declared, Ioana Marian: None declared, Megan Goff: None declared, Gretchen Brewer: None declared, Malvika Gulati: None declared, Lucy Eldridge: None declared, Patrick Julier: None declared, Catherine Minns Lowe: None declared, Vicki Barber: None declared, Victoria Glover: None declared, Charles Mackworth-Young: None declared, Tonia Vincent Consultant of: Pfizer, Grant/research support from: Grant support from Fidia, Biosplice, Novartis, Pfizer as part of their contribution to an international consortium., Sarah E Lamb: None declared, Katy Vincent: None declared, Susan J Dutton: None declared, Fiona E Watt Consultant of: Pfizer, Grant/research support from: Pfizer and from Astellas Pharma (> 3 years ago)

Evolution of the complex transcription network controlling biofilm formation in Candida species

We examine how a complex transcription network composed of seven 'master' regulators and hundreds of target genes evolved over a span of approximately 70 million years. The network controls biofilm formation in several Candida species, a group of fungi that are present in humans both as constituents of the microbiota and as opportunistic pathogens. Using a variety of approaches, we observed two major types of changes that have occurred in the biofilm network since the four extant species we examined last shared a common ancestor. Master regulator 'substitutions' occurred over relatively long evolutionary times, resulting in different species having overlapping but different sets of master regulators of biofilm formation. Second, massive changes in the connections between the master regulators and their target genes occurred over much shorter timescales. We believe this analysis is the first detailed, empirical description of how a complex transcription network has evolved.

Management of aggressive posterior retinopathy of prematurity in oculocutaneous albinism

A male infant, born preterm at 32 weeks of gestation, was referred at 36-week postmenstrual age for retinopathy of prematurity (ROP) screening. He had nystagmus, generalised hypopigmentation of skin, hair and eyes with preaxial polydactyly. The fundus was depigmented with prominently visible choroidal vessels. The retinal vessels were dilated, tortuous at zone 1. There was presence of arcading, shunting of vessels with presence of vitreous haemorrhage in the left eye. A diagnosis of aggressive posterior retinopathy of prematurity (APROP) in association with oculocutaneous albinism (OCA) was made.Half-dose intravitreal bevacizumab was used to treat the vascular condition. After 2 weeks, there was complete regression of APROP with a completely mature retina observed at 4 months post-treatment. Herein, we describe the role of red-free light for screening ROP in infants with OCA; challenges in the management of ROP with laser photocoagulation compared with intravitreal anti-vascular endothelial growth factor therapy.

Hypertensive disorders of pregnancy and impact on in-hospital cardio-obstetric outcomes

Introduction

Hypertensive disorders of pregnancy (HDP) are a major cause of maternal morbidity. However, short-term outcomes of HDP subgroups remain unknown.

Methods

Using the United States National Inpatient Sample database, all delivery hospitalizations between 2004 and 2014 with or without HDP (preeclampsia/eclampsia, chronic hypertension, superimposed preeclampsia on chronic hypertension and gestational hypertension) were analysed to examine the association between HDP and adverse in-hospital outcomes.

Results

We identified &gt;44 million delivery hospitalizations, within which the prevalence of HDP increased from 8% to 11% over a decade with increasing comorbidity burden. Women with chronic hypertension have higher risks of myocardial infarction, peripartum cardiomyopathy, arrhythmia and stillbirth compared to women with preeclampsia. Out of all HDP subgroups, the superimposed preeclampsia population had the highest risk of stroke (OR 7.83, 95% CI 6.25, 9.80), myocardial infarction (OR 5.20, 95% CI 3.11, 8.69), peripartum cardiomyopathy (OR 4.37, 95% CI 3.64, 5.26), preterm birth (OR 4.65, 95% CI 4.48, 4.83), placental abruption (OR 2.22, 95% CI 2.09, 2.36), and stillbirth (OR 1.78, 95% CI 1.66, 1.92) compared to women without HDP. In conclusion, we are the first to evaluate chronic SH without superimposed preeclampsia as a distinct subgroup in HDP and show that women with chronic SH are at even higher risk of some adverse outcomes compared to women with preeclampsia.

Conclusion

The chronic hypertension population, with and without superimposed preeclampsia, is a particularly high risk group and may benefit from increased antenatal surveillance and the use of a prognostic risk assessment model incorporating HDP to stratify intrapartum care.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): NIHR

Acute myocardial infarction in several mental illness: a nationwide analysis of prevalence, management strategies and outcomes

Background

Severe mental illness (SMI) is associated with an increased risk of cardiovascular disease and mortality. However, it is unclear whether SMI patients are just as likely to receive guideline-recommended therapy for AMI as those without mental illness.

Purpose

To examine national-level estimates of the prevalence, management strategies and in-hospital clinical outcomes of SMI patients presenting with AMI.

Methods

All AMI hospitalisations from the United States National Inpatient Sample were included, stratified by mental health status in to 5 groups: no-SMI, Schizophrenia, “Other non-organic psychoses” (ONOP), Bipolar Disorder and Major Depression. Multivariable logistic regression modelling was performed to examine the association between SMI subtypes and receipt of invasive management and subsequent in-hospital clinical outcomes, expressed as adjusted odds ratios (aOR) and 95% confidence intervals (CI).

Results

Out of 6,968,777 AMI hospitalisations between 2004 and 2014, a total of 439,544 (6.5%) had an SMI diagnosis. The prevalence of SMI amongst the ACS population doubled over the study period (from 4.5% in 2004 to 9.5% in 2014), primarily due to an increase in Major Depression and Bipolar Disorder diagnoses. All SMI subtypes were less likely to receive coronary angiography and PCI, with the Schizophrenia group being at least odds of either procedure (aOR 0.46 95% CI 0.45, 0.48 and aOR 0.57 95% CI 0.55, 0.59, respectively). Although patients with Schizophrenia and ONOP experienced higher crude rates of in-hospital mortality and stroke compared to those without SMI, only Schizophrenia patients were associated with increased odds of mortality (aOR 1.10 95% CI 1.04, 1.16), while ONOP were the only group at increased odds of stroke (aOR 1.53 95% CI 1.42,1.65) following multivariate adjustment. Patients with ONOP were the only group associated with increased odds of in-hospital bleeding compared to those without SMI (aOR 1.11 95% CI 1.04,1.17).

Conclusion

Patients with SMI are less likely to receive invasive management for AMI, with women and schizophrenia diagnosis being the strongest predictors of conservative management. Schizophrenia and “other non-organic psychoses” are the only SMI subtypes associated with adverse clinical outcomes after AMI. A multidisciplinary approach between psychiatrists and cardiologists could improve outcomes of this high-risk population.

Odds of management and clinical outcomes

Funding Acknowledgement

Type of funding source: None

Combination of Antifungal Drugs and Protease Inhibitors Prevent Candida albicans Biofilm Formation and Disrupt Mature Biofilms

Biofilms formed by the fungal pathogen Candida albicans are resistant to many of the antifungal agents commonly used in the clinic. Previous reports suggest that protease inhibitors, specifically inhibitors of aspartyl proteases, could be effective antibiofilm agents. We screened three protease inhibitor libraries, containing a total of 80 compounds for the abilities to prevent C. albicans biofilm formation and to disrupt mature biofilms. The compounds were screened individually and in the presence of subinhibitory concentrations of the most commonly prescribed antifungal agents for Candida infections: fluconazole, amphotericin B, or caspofungin. Although few of the compounds affected biofilms on their own, seven aspartyl protease inhibitors inhibited biofilm formation when combined with amphotericin B or caspofungin. Furthermore, nine aspartyl protease inhibitors disrupted mature biofilms when combined with caspofungin. These results suggest that the combination of standard antifungal agents together with specific protease inhibitors may be useful in the prevention and treatment of C. albicans biofilm infections.

P681Acute Myocardial Infarction in patients with Leukaemia: A national analysis of prevalence, predictors and outcomes in United States hospitalisations (2004 to 2014)

Background

Patients with leukaemia are at increased risk of cardiovascular events. There is limited outcomes data for patients with a history of leukaemia who present with an acute myocardial infarction (AMI).

Purpose

To examine the prevalence and clinical characteristics of patients with leukaemia presenting with AMI, and evaluate differences in clinical outcomes according to the subtype of leukaemia in comparison to patients without leukaemia.

Methods

We analysed the Nationwide Inpatient Sample (2004–2014) for patients with a primary discharge diagnosis of AMI and concomitant leukaemia, and further stratified according to the subtype of leukaemia into 4 groups; AML; ALL; CML; and CLL. Multiple logistic regression was conducted to identify the association between leukaemia and major acute cardiovascular and cerebrovascular events (MACCE; composite of mortality, stroke and cardiac complications) and bleeding.

Results

Out of 6,750,927 AMI admissions, a total of 21,694 patients had a leukaemia diagnosis. The leukaemia group experienced higher rates of MACCE (11.8% vs. 7.8%), mortality (10.3% vs. 5.8%) and bleeding (5.6% vs. 5.3%). Following adjustments, leukaemia was independently associated with increased odds of MACCE (OR 1.26 [1.20,1.31]) and mortality (OR 1.43 [1.37,1.50]) without an increased risk of bleeding (OR 0.86 [0.81,0.92]). Acute myeloid leukaemia (AML) was associated with approximately three-fold risk of MACCE (RR 2.81 [2.51, 3.13]) and a four-fold risk of mortality (RR 3.75 [3.34, 4.22]) (Figure 1). Patients with leukaemia were less likely to undergo coronary angiography (CA) (48.5% vs. 64.5%) and percutaneous coronary intervention (PCI) (28.2% vs. 42.9%) compared to those without leukaemia.

Figure 1.Relative risk of adverse events

Conclusion

Patients with leukaemia, especially those with AML, are associated with poor clinical outcomes after AMI, and are less likely to receive CA and PCI compared to those without leukaemia. A multi-disciplinary approach between cardiologists and haematology oncologists may improve the outcomes of patients with leukaemia after AMI.

Comparison of Laryngeal Mask Airway with Tracheal Tube for Ophthalmic Surgery in Paediatric Patients

This study of sixty ASA grade 1 or 2 children, aged 1 to 12 years, undergoing elective ophthalmic procedures, compared the use of the laryngeal mask airway (LMA) with that of an endotracheal tube. Changes in intraocular pressure and haemodynamic parameters, and intraoperative and postoperative complications were measured. Patients were randomly allocated into two groups of 30 patients. In group 1, the airway was secured with an LMA and in group 2 with an endotracheal tube. A standard technique of general anaesthesia incorporating positive pressure ventilation was used in both groups. The changes in intraocular pressure, heart rate (HR) and mean arterial pressure (MAP) were observed before and after insertion of the airway device, two minutes after insertion, and pre and post removal of the device. The incidence of airway complications was also noted. There was no significant change in mean intraocular pressure after insertion of the LMA, but removal caused a significant increase to 19.3± 7.6 mmHg (from a baseline of 13.9±4.3 mmHg). In the endotracheal tube group, intubation increased the mean intraocular pressure significantly to 19.9±7.3 mmHg (from a baseline of 13.1±4.0 mmHg) and extubation caused an increase to 24.6±10.4 mmHg which was clinically as well as statistically significant. The incidence of postoperative coughing was lower in the LMA group, but the incidence of vomiting higher. Two patients had displacement of the LMA during the procedure. We conclude that the use of an LMA is associated with less increase in intraocular pressure than the use of an endotracheal tube in children.

In Vitro Culturing and Screening of Candida albicans Biofilms

Candida albicans is a normal member of the human microbiota that asymptomatically colonizes healthy individuals, however it is also an opportunistic pathogen that can cause severe infections, especially in immunocompromised individuals. The medical impact of C. albicans depends, in part, on its ability to form biofilms, communities of adhered cells encased in an extracellular matrix. Biofilms can form on both biotic and abiotic surfaces, such as tissues and implanted medical devices. Once formed, biofilms are highly resistant to antifungal agents and the host immune system, and can act as a protected reservoir to seed disseminated infections. Here, we present several in vitro biofilm protocols, including protocols that are optimized for high-throughput screening of mutant libraries and antifungal compounds. We also present protocols to examine specific stages of biofilm development and protocols to evaluate interspecies biofilms that C. albicans forms with interacting microbial partners. © 2018 by John Wiley & Sons, Inc.

Whole RNA-Sequencing and Transcriptome Assembly of Candida albicans and Candida africana under Chlamydospore-Inducing Conditions

Candida albicans is the most common cause of life-threatening fungal infections in humans, especially in immunocompromised individuals. Crucial to its success as an opportunistic pathogen is the considerable dynamism of its genome, which readily undergoes genetic changes generating new phenotypes and shaping the evolution of new strains. Candida africana is an intriguing C. albicans biovariant strain that exhibits remarkable genetic and phenotypic differences when compared with standard C. albicans isolates. Candida africana is well-known for its low degree of virulence compared with C. albicans and for its inability to produce chlamydospores that C. albicans, characteristically, produces under certain environmental conditions. Chlamydospores are large, spherical structures, whose biological function is still unknown. For this reason, we have sequenced, assembled, and annotated the whole transcriptomes obtained from an efficient C. albicans chlamydospore-producing clinical strain (GE1), compared with the natural chlamydospore-negative C. africana clinical strain (CBS 11016). The transcriptomes of both C. albicans (GE1) and C. africana (CBS 11016) clinical strains, grown under chlamydospore-inducing conditions, were sequenced and assembled into 7,442 (GE1 strain) and 8,370 (CBS 11016 strain) high quality transcripts, respectively. The release of the first assembly of the C. africana transcriptome will allow future comparative studies to better understand the biology and evolution of this important human fungal pathogen.

Visualization of Biofilm Formation in Candida albicans Using an Automated Microfluidic Device

Candida albicans is the most common fungal pathogen of humans, causing about 15% of hospital-acquired sepsis cases. A major virulence attribute of C. albicans is its ability to form biofilms, structured communities of cells attached to biotic and abiotic surfaces. C. albicans biofilms can form on host tissues, such as mucosal layers, and on medical devices, such as catheters, pacemakers, dentures, and joint prostheses. Biofilms pose significant clinical challenges because they are highly resistant to physical and chemical perturbations, and can act as reservoirs to seed disseminated infections. Various in vitro assays have been utilized to study C. albicans biofilm formation, such as microtiter plate assays, dry weight measurements, cell viability assays, and confocal scanning laser microscopy. All of these assays are single end-point assays, where biofilm formation is assessed at a specific time point. Here, we describe a protocol to study biofilm formation in real-time using an automated microfluidic device under laminar flow conditions. This method allows for the observation of biofilm formation as the biofilm develops over time, using customizable conditions that mimic those of the host, such as those encountered in vascular catheters. This protocol can be used to assess the biofilm defects of genetic mutants as well as the inhibitory effects of antimicrobial agents on biofilm development in real-time.

Imaging of esophageal tuberculosis: A review of 23 cases

Purpose: To evaluate the various radiological abnormalities in patients with proven esophageal tuberculosis.

Material and Methods: The case records of 23 patients with proven esophageal tuberculosis were evaluated retrospectively for various radiological abnormalities. Twenty-two patients had secondary involvement of esophagus in the form of direct extension of mediastinal and pulmonary tuberculosis or spinal tuberculosis. Only 1 patient had primary involvement of the esophagus with no evidence of disease elsewhere. The diagnosis was confirmed by endoscopic and CT-guided biopsy/aspiration cytology in 7 and 6 cases, respectively. Diagnosis was made on the basis of surgical biopsy of lymph node and autopsy in 1 patient each. In the remaining 8 patients the diagnosis was based on radiological and endoscopic findings and the response to antituberculous treatment.

Results: Chest radiography (CXR) was abnormal in 65% patients. While the findings were non-conclusive for esophageal tuberculosis, characteristic lesions of tuberculosis in lungs or spine were suggestive of tuberculous etiology. In 15 patients, CT of the chest confirmed the corresponding CXR findings and also showed additional findings of mediastinal lymphadenopathy when CXR was normal. Fourteen patients showed mediastinal lymphadenopathy on CT of the chest. In all these patients, more than one group of lymph nodes was involved. The characteristic hypodense center of lymph nodes suggestive of tuberculosis was seen in 12 patients. Radiological abnormalities seen in barium swallow examination were extrinsic compression, traction diverticula, strictures, sinus/fistulous tracts, kinking and pseudotumor mass of esophagus in decreasing order of frequency. The middle third of the esophagus was found to be the most frequent site of involvement.

S-nitrosomycothiol reductase and mycothiol are required for survival under aldehyde stress and biofilm formation in Mycobacterium smegmatis

We show that Mycobacterium smegmatis mutants disrupted in mscR, coding for a dual function S-nitrosomycothiol reductase and formaldehyde dehydrogenase, and mshC, coding for a mycothiol ligase and lacking mycothiol (MSH), are more susceptible to S-nitrosoglutathione (GSNO) and aldehydes than wild type. MSH is a cofactor for MscR, and both mshC and mscR are induced by GSNO and aldehydes. We also show that a mutant disrupted in egtA, coding for a γ-glutamyl cysteine synthetase and lacking in ergothioneine, is sensitive to nitrosative stress but not to aldehydes. In addition, we find that MSH and S-nitrosomycothiol reductase are required for normal biofilm formation in M. smegmatis, suggesting potential new therapeutic pathways to target to inhibit or disrupt biofilm formation. © 2016 IUBMB Life, 68(8):621-628, 2016.

Molecular Characterization of the N-Acetylglucosamine Catabolic Genes in Candida africana, a Natural N-Acetylglucosamine Kinase (HXK1) Mutant

Background

In this study we report the genetic characterization, including expression analysis, of the genes involved in the uptake (NGT1) and catabolism (HXK1/NAG5, DAC1/NAG2, NAG1) of the aminosugar N-acetylglucosamine (GlcNAc) in Candida africana, a pathogenic biovariant of Candida albicans that is naturally unable to assimilate the GlcNAc.

Results

DNA sequence analysis of these genes revealed a number of characteristic nucleotide substitutions including a unique and distinctive guanine insertion that shifts the reading frame and generates a premature stop codon (TGA) 154 bp downstream of the ATG start codon of the HXK1 gene encoding the GlcNAc-kinase, a key enzyme of the GlcNAc catabolic pathway. However, all examined genes produced transcripts even though different levels of expression were observed among the Candida isolates examined. In particular, we found an HXK1-idependent relationship of the NGT1 gene and a considerable influence of the GlcNAc-kinase functionality on the transcription of the DAC1 and NAG1 genes. Additional phenotypic analysis revealed that C. africana isolates are hyperfilamentous in the first 24-48h of growth on filament-inducing media and revert to the yeast morphological form after 72h of incubation on these media.

Conclusions

Our results show that C. africana is a natural HXK1 mutant, displaying a number of phenotypic characteristics distinct from typical C. albicans isolates.

Candida albicans biofilms: development, regulation, and molecular mechanisms

A major virulence attribute of Candida albicans is its ability to form biofilms, densely packed communities of cells adhered to a surface. These biofilms are intrinsically resistant to conventional antifungal therapeutics, the host immune system, and other environmental factors, making biofilm-associated infections a significant clinical challenge. Here, we review current knowledge on the development, regulation, and molecular mechanisms of C. albicans biofilms.

Functional interaction between ribosomal protein L6 and RbgA during ribosome assembly

RbgA is an essential GTPase that participates in the assembly of the large ribosomal subunit in Bacillus subtilis and its homologs are implicated in mitochondrial and eukaryotic large subunit assembly. How RbgA functions in this process is still poorly understood. To gain insight into the function of RbgA we isolated suppressor mutations that partially restored the growth of an RbgA mutation (RbgA-F6A) that caused a severe growth defect. Analysis of these suppressors identified mutations in rplF, encoding ribosomal protein L6. The suppressor strains all accumulated a novel ribosome intermediate that migrates at 44S in sucrose gradients. All of the mutations cluster in a region of L6 that is in close contact with helix 97 of the 23S rRNA. In vitro maturation assays indicate that the L6 substitutions allow the defective RbgA-F6A protein to function more effectively in ribosome maturation. Our results suggest that RbgA functions to properly position L6 on the ribosome, prior to the incorporation of L16 and other late assembly proteins.

Ribosomes are complex macromolecular machines that carry out the essential function of protein synthesis in the cell. The assembly of ribosomal subunits is a multistep process that involves the accurate and timely assembly of 3 rRNA molecules and>50 ribosomal-proteins. In recent years many ribosome assembly factors have been identified in bacterial and eukaryotic cells; however, their precise functions in ribosome biogenesis are poorly understood. We have previously shown that the GTPase RbgA, a protein conserved from bacteria to humans, is essential for ribosome assembly in Bacillus subtilis. Here, we show that growth defect caused by a mutation in RbgA is partially suppressed by mutations in ribosomal protein L6. The suppressor strains accumulate novel ribosomal intermediates that appear to suppress the RbgA defect by weakening the interaction of L6 for the ribosome and facilitating RbgA dependent assembly. Our work provides evidence for a functional interaction between ribosome assembly factor RbgA and ribosomal protein L6 during assembly, a function that is likely important for mitochondrial, chloroplast, and eukaryotic ribosome assembly as well.

Mutational analysis of the ribosome assembly GTPase RbgA provides insight into ribosome interaction and ribosome-stimulated GTPase activation

Ribosome biogenesis GTPase A protein (RbgA) is an essential GTPase required for the biogenesis of the 50S subunit in Bacillus subtilis. Homologs of RbgA are widely distributed in bacteria and eukaryotes and are implicated in ribosome assembly in the mitochondria, chloroplast and cytoplasm. Cells depleted of RbgA accumulate an immature large subunit that is missing key ribosomal proteins. RbgA, unlike many members of the Ras superfamily of GTPases, lacks a defined catalytic residue for carrying out guanosine triphosphate (GTP) hydrolysis. To probe RbgA function in ribosome assembly, we used a combined bioinformatics, genetic and biochemical approach. We identified a RNA-binding domain within the C-terminus of RbgA that is structurally similar to AmiR–NasR Transcription Anti-termination Regulator (ANTAR) domains, which are known to bind structured RNA. Mutation of key residues in the ANTAR domain altered RbgA association with the ribosome. We identified a putative catalytic residue within a highly conserved region of RbgA, His9, which is contained within a similar PGH motif found in elongation factor Tu (EF-Tu) that is required for GTP hydrolysis on interaction with the ribosome. Finally, our results support a model in which the GTPase activity of RbgA directly participates in the maturation of the large subunit rather than solely promoting dissociation of RbgA from the 50S subunit.

Biochemical characterization of ribosome assembly GTPase RbgA in Bacillus subtilis

The ribosome biogenesis GTPase A protein RbgA is involved in the assembly of the large ribosomal subunit in Bacillus subtilis, and homologs of RbgA are implicated in the biogenesis of mitochondrial, chloroplast, and cytoplasmic ribosomes in archaea and eukaryotes. The precise function of how RbgA contributes to ribosome assembly is not understood. Defects in RbgA give rise to a large ribosomal subunit that is immature and migrates at 45 S in sucrose density gradients. Here, we report a detailed biochemical analysis of RbgA and its interaction with the ribosome. We found that RbgA, like most other GTPases, exhibits a very slow k(cat) (14 h(-1)) and has a high K(m) (90 μM). Homology modeling of the RbgA switch I region using the K-loop GTPase MnmE as a template suggested that RbgA requires K(+) ions for GTPase activity, which was confirmed experimentally. Interaction with 50 S subunits, but not 45 S intermediates, increased GTPase activity by ∼55-fold. Stable association with 50 S subunits and 45 S intermediates was nucleotide-dependent, and GDP did not support strong interaction with either of the subunits. GTP and guanosine 5'-(β,γ-imido)triphosphate (GMPPNP) were sufficient to promote association with the 45 S intermediate, whereas only GMPPNP was able to support binding to the 50 S subunit, presumably due to the stimulation of GTP hydrolysis. These results support a model in which RbgA promotes a late step in ribosome biogenesis and that one role of GTP hydrolysis is to stimulate dissociation of RbgA from the ribosome.

Evaluation of gall bladder carcinoma with dynamic magnetic resonance imaging and magnetic resonance cholangiopancreatography

The objective of this study is to evaluate the efficacy of dynamic MRI with magnetic resonance cholangiopancreatography (MRCP) in the preoperative assessment of gall bladder carcinoma. Magnetic resonance imaging and MRCP were carried out in 15 patients with gall bladder carcinoma before surgery and the imaging findings correlated with surgical and pathological findings. Gall bladder carcinoma manifested as focal or diffuse wall thickening in 73% (11/15) and as a mass replacing the gall bladder in 27% (4/15). All tumours showed enhancement in the early phase, which persisted into the delayed phase. The sensitivity and specificity of MRI with MRCP in detecting hepatic invasion, lymph node metastasis and bile duct invasion was 87.5 and 86%, 60 and 90%, and 80 and 100%, respectively. Magnetic resonance imaging correctly diagnosed duodenal invasion in only 50% and in none of the two patients with peritoneal metastasis. In conclusion, dynamic MRI with MRCP is an accurate and a reliable method of showing gall bladder carcinoma and in assessing its local and regional extent as part of preoperative assessment.

Clinical profile, diagnosis and management of patients presenting with symptomatic pulmonary embolism

OBJECTIVE

To study the clinical profile and diagnostic methods in patients with symptomatic pulmonary embolism (PE).

METHODS

Prospective assessment of clinical features, radiology and outcome of patients presenting with symptomatic PE over an 18-month period.

RESULTS

During study period, 24 patients with a mean age of 39 +/- 12.1 years were diagnosed to have symptomatic pulmonary embolism. Dyspnoea (91.7%) and cough (58.3%) were the predominant complaints. Spiral computed tomographic pulmonary angiography (CTPA) was performed in 21 (87.5%) patients and perfusion scans in 14 (58.4%) patients. Echocardiography performed in all patients revealed evidence of pulmonary artery hypertension and right ventricular dyskinesia in 20 (83.3%) and 15 (62.5%) patients, respectively. Thrombolysis with streptokinase was performed in 14 (58.3%) patients. All patients received low molecular weight heparin followed by warfarin. Of the 24 patients, 20 (83.3%) were discharged and are under regular follow-up; four patients died.

CONCLUSIONS

Pulmonary embolism is a common problem and can be easily diagnosed provided it is clinically suspected. Early diagnosis and aggressive management is the key to successful outcome.

Comparison of efficacy of spironolactone with metformin in the management of polycystic ovary syndrome: an open-labeled study

We compared the efficacy of spironolactone (50 mg/d) with metformin (1000 mg/d) after random allocation in 82 adolescent and young women with polycystic ovary syndrome (PCOS) on body mass index (BMI), waist-to-hip ratio, blood pressure, menstrual cyclicity, hirsutism, hormonal levels, glycemia, and insulin sensitivity at baseline and at the 3rd and 6th months of treatment. Sixty-nine women who completed the follow-up had a mean age of 22.6 +/- 5.0 yr and mean BMI of 26.8 +/- 4.0 kg/m2. The number of menstrual cycles in the spironolactone and metformin groups increased from 6.6 +/- 2.1 and 5.7 +/- 2.3 at baseline to 9.0 +/- 1.9 and 7.4 +/- 2.6 at 3rd month and to 10.2 +/- 1.9 and 9.1 +/- 2.0/ year at the 6th month (P = 0.0037), respectively. The hirsutism score decreased from 12.9 +/- 3.2 and 12.5 +/- 4.9 at baseline to 10.1 +/- 3.1 and 11.4 +/- 4.1 at the 3rd month and to 8.7 +/- 1.9 and 10.0 +/- 3.3 at the 6th month, respectively. Both groups showed improvement in glucose tolerance and insulin sensitivity, although the metformin effect was significant in the latter. Serum LH/FSH and testosterone decreased in both groups. BMI, waist-to-hip ratio, and blood pressure did not change with either drug. We conclude that both drugs are effective in the management of PCOS. Spironolactone appears better than metformin in the treatment of hirsutism, menstrual cycle frequency, and hormonal derangements and is associated with fewer adverse events.

In vivo proton magnetic resonance spectroscopy (MRS) and single photon emission computerized tomography (SPECT) in systemic lupus erythematosus (SLE)

Neuropsychiatric involvement in SLE (NP-SLE) may not be picked up by routine neuroimaging procedures like computerized tomography (CT) or magnetic resonance imaging (MRI). We prospectively studied the role of single photon emission computerized tomography (SPECT) and magnetic resonance spectroscopy (MRS) in detection of NP-SLE in 20 patients with lupus (10 with clinical NP involvement and 10 without) and 9 healthy controls. MRI abnormalities were seen in 5/10 patients with NP-SLE while the MRI was normal in all the lupus patients without clinical NP involvement. Perfusion defects on SPECT were seen in as many as 8/10 patients with NP-SLE while only 1/10 lupus patients without clinical NP involvement and none of the healthy controls demonstrated perfusion defects. MRS revealed abnormal metabolite ratios in all patients with NP-SLE and as many as 8 lupus patients without clinical NP features. Normal metabolite ratios were observed in healthy controls. SPECT and MRS can help detect changes not evident on MRI and may serve as useful supplements to existing neuroimaging techniques in the diagnosis of NP-SLE. The precise significance of alterations in regional cerebral blood flow on SPECT and neurometabolite ratios on MRS needs larger, longitudinal studies.

Contrast-free unilateral endoscopic palliation in malignant hilar biliary obstruction: new method

BACKGROUND

Bilateral endoscopic drainage is difficult in malignant hilar biliary obstruction. Recently, unilateral drainage in malignant hilar biliary obstruction has been shown to be equally effective. However, contrast injection leads to cholangitis. There have been no reported studies on contrast-free metal stenting in malignant hilar biliary obstruction. The present study was undertaken to evaluate the results of contrast-free unilateral metal stenting in type II malignant hilar biliary obstruction.

METHODS

We prospectively studied the results of unilateral metal stenting in type II malignant hilar biliary obstruction without contrast injection in 18 patients.

RESULTS

A successful endoscopic drainage was achieved in 100% (18/18) of patients with hilar strictures. Cholangitis and 30-day mortality occurred in none.

CONCLUSIONS

Unilateral endoscopic metal stenting without contrast in type II malignant hilar biliary obstruction is a safe and effective method of palliation.

A prospective study of the incidence and open-label treatment of interferon-induced major depressive disorder in patients with hepatitis C

Interferon (IFN) therapy has been associated with the development of Major Depressive Disorder (MDD) when given to patients with hepatitis C (HCV). The incidence, time course, risk factors, and treatment of IFN-induced MDD are poorly understood. The objectives of the present study were to determine the incidence of IFN-induced MDD, as well as to determine the efficacy of open-label antidepressant treatment, in particular selective serotonin reuptake inhibitors (SSRIs) for IFN-induced MDD. Thirty-nine HCV patients on IFN therapy were monitored weekly using the Beck Depression Inventory (BDI). Those who became depressed were treated with citalopram, a SSRI antidepressant. Main outcome measures included the incidence of IFN-induced MDD, as well as response rates to antidepressants in those patients who developed IFN-induced MDD. Our results showed that 13 of 39 patients (33%) developed IFN-induced MDD. There were no differences in age, gender, past history of MDD, or substance use between those who became depressed and those who did not. However, there were significantly fewer African American patients in the depressed group. Patients who developed IFN-induced MDD were on IFN therapy for an average of 12.1 weeks prior to the development of MDD. Eleven of 13 patients (85%) were responsive to antidepressant treatment. We conclude that IFN-induced MDD is common in HCV patients. Health care providers should follow IFN-treated HCV patients for the development of MDD, particularly between the 2nd and 5th months of IFN therapy. SSRIs, in particular citalopram, are an effective treatment for IFN-induced depression in HCV patients.

Imaging of esophageal tuberculosis: a review of 23 cases

PURPOSE

To evaluate the various radiological abnormalities in patients with proven esophageal tuberculosis.

MATERIAL AND METHODS

The case records of 23 patients with proven esophageal tuberculosis were evaluated retrospectively for various radiological abnormalities. Twenty-two patients had secondary involvement of esophagus in the form of direct extension of mediastinal and pulmonary tuberculosis or spinal tuberculosis. Only 1 patient had primary involvement of the esophagus with no evidence of disease elsewhere. The diagnosis was confirmed by endoscopic and CT-guided biopsy/aspiration cytology in 7 and 6 cases, respectively. Diagnosis was made on the basis of surgical biopsy of lymph node and autopsy in 1 patient each. In the remaining 8 patients the diagnosis was based on radiological and endoscopic findings and the response to antituberculous treatment.

RESULTS

Chest radiography (CXR) was abnormal in 65% patients. While the findings were non-conclusive for esophageal tuberculosis, characteristic lesions of tuberculosis in lungs or spine were suggestive of tuberculous etiology. In 15 patients, CT of the chest confirmed the corresponding CXR findings and also showed additional findings of mediastinal lymphadenopathy when CXR was normal. Fourteen patients showed mediastinal lymphadenopathy on CT of the chest. In all these patients, more than one group of lymph nodes was involved. The characteristic hypodense center of lymph nodes suggestive of tuberculosis was seen in 12 patients. Radiological abnormalities seen in barium swallow examination were extrinsic compression, traction diverticula, strictures, sinus/fistulous tracts, kinking and pseudotumor mass of esophagus in decreasing order of frequency. The middle third of the esophagus was found to be the most frequent site of involvement.

Mucoepidermoid carcinoma of the bronchus: is conservative surgery always justified?

A case of mucoepidermoid carcinoma of the bronchus in a 7-year-old boy is reported. The patient underwent right pneumonectomy. Histologically, the tumor was a low-grade muco-epidermoid carcinoma arising from the bronchus with lymph node metastasis in the drainage area. Presence of lymph node metastasis in this low-grade tumor suggests the possibility of early progression of disease in what has until now been considered a very slow growing tumor. Aggressive surgery may be necessary in these situations.

Cerebrospinal fluid pseudocyst of the breast

Cerebrospinal fluid pseudocyst of the breast is a rare complication of ventriculoperitoneal shunt placement. Two cases of cerebrospinal pseudocyst of the breast are reported here. The mammography and ultrasound findings in these two cases are described.

Thrombolytic therapy of a left-sided prosthetic valve thrombosis without hemodynamic obstruction: a case report

We report a case of a 38-year-old woman with a prosthetic mitral valve who presented with multiple embolic events. Transesophageal echocardiography was used to diagnose nonobstructive thrombi on the prosthetic valve. She underwent successful thrombolytic therapy. The patient was discovered to be in a hypercoagulable state, which probably was caused by the concomitant use of phenytoin. We review the literature for diagnosis and treatment of nonobstructive prosthetic valve thrombosis.

Ultrasound guided fine needle aspiration biopsy in mediastinal tuberculosis

SETTING

Diagnosis of mediastinal tuberculosis (TB) is difficult due to non-specific clinical features and lack of characteristic radiographic features. Histopathological confirmation has often required computed tomography guided fine needle aspiration biopsy (FNAB) or even invasive procedures such as mediastinoscopy or open/surgical biopsy. FNAB under ultrasound (US) guidance can also be performed in this clinical setting.

OBJECTIVE

To define the role of percutaneous US guided FNAB in the diagnosis of mediastinal tuberculosis.

DESIGN

Twenty-six patients with a proven diagnosis of mediastinal TB formed the study group. Chest radiographs and sputum examination were negative. FNAB was performed via suprasternal (n = 20) and parasternal (n = 6) route under sonographic guidance using 22G spinal needle. Aspirates were considered positive for TB when epithelioid cell granuloma with caseation necrosis and/or the presence of Mycobacterium tuberculosis by acid-fast bacilli (AFB) or culture was demonstrated, indeterminate when epithelioid cell granulomas were seen but without caseation necrosis or AFB, and negative when aspirate contained non-representative material.

RESULTS

A total of 30 biopsies were performed in the 26 patients, including repeat biopsy and biopsy of different sites in two patients each. FNAB was positive for TB in 20 of the 26 patients. In four, AFB were demonstrated, and in seven culture was positive for M. tuberculosis; in the remaining six patients, cytologic diagnosis was indeterminate in four and negative in two. No procedure related complications were noted.

CONCLUSION

Ultrasound guided FNAB is a safe, effective technique in the diagnosis of mediastinal TB.

Ultrasound-guided transthoracic co-axial biopsy of thoracic mass lesions

PURPOSE

To compare the diagnostic yield of fine-needle aspiration biopsy (FNAB) and cutting needle biopsy in thoracic lesions.

MATERIAL AND METHODS

Thirty patients with thoracic mass lesions were subjected to ultrasound-guided co-axial FNAB and cutting needle biopsy using 0.7 mm aspirating and 1.0-mm cutting needles, respectively. The diagnostic yield of the individual modalities was compared with the combined yield.

RESULTS

A conclusive diagnosis was obtained in 76.6% (n=23) of patients by FNAB and in 66.6% (n=20) by cutting needle biopsy. The combined diagnostic yield of FNAB and cutting needle biopsy was 93.3% (n=28) with a significant statistical difference (p<0.03) as compared to cutting biopsy alone. Of the patients, 23.2% (n=7) had benign and 76.6% (n=23) malignant aetiologies. The diagnostic yield of FNAB versus cutting needle biopsy in benign lesions was 57.1% (n=4) and 100% (n=7), respectively. The diagnostic yield of FNAB versus cutting needle biopsy in malignant lesions was 82.6% (n=19) and 56.5%, (n=13). Two patients remained undiagnosed by either modality. There were no complications.

CONCLUSION

FNAB and cutting needle biopsy are complementary to each other and attempts should be made to obtain small tissue cores in addition to routine cytologic specimens in diagnosing thoracic lesions, especially in benign pathologies. US provides a safe guidance modality for lesions abutting the chest wall.