- Volume 2, Issue 2, 2020
Volume 2, Issue 2, 2020
- Abstracts from the Federation of Infection Societies Conference 2019
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- Oral Abstract
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A Paradoxical Puzzle: Delayed reaction during treatment for disseminated BCG
More LessA 74-year-old man with no previous history of tuberculosis presented with malaise, pyrexia (39°C) and 35kg weight loss, 16 months after TURBT for transitional cell carcinoma of the bladder and BCG instillation. He was pancytopaenic (Hb 84, Plt 99, WCC 2.94) and CT imaging showed splenomegaly, small pleural effusions and a sinusoidal lesion which on biopsy was not malignant. He did not have any promiment lymphadenopathy or pulmonary consolidation. Autoimmune and HIV screening were negative (CD4 310 (57%)) and both TTE and TOE showed no vegetations. IGRA/Quantiferon-Gold testing was positive and bone marrow biopsy yielded granuloma but no AFB on histology. Standard quadruple therapy was commenced for suspected disseminated mycobacterial disease. Mycobacterial cultures of early morning urine, blood and bone marrow were all positive and later identified as BCG on whole genome sequencing, sensitive to Rifampicin, Isoniazid, Amikacin and Moxifloxacin with undetermined Ethambutol sensitivity. Fully compliant with treatment, he developed a solid part cystic irregular enhancing 35mmmass encasing his left internal carotid artery seven months into treatment. ϒ-IFN-axis testing showed adequate responses to IL12 and IFN stimulation. Biopsy revealed AFB-positive granulomata leading to additional steroids for a presumed paradoxical reaction as well as treatment intensification with Moxifloxacin and Amikacin whilst awaiting cultures, the latter of which was discontinued following negative culture results and clinical and radiological improvement. Paradoxical reactions occur not infrequently (2-23%) and can present delayed (14-270 days) following initiation of treatment. He gained 25kg and made an uneventful recovery having received 18 months of BCG treatment.
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Streptococcus agalactiae macrolide/lincosamide resistance; implications for puerperal antimicrobial therapy
More LessIntroduction
There is no routine screening for antenatal Group B Streptococcus (GBS) carriage in the UK. However where GBS is identified from clinical urine/vaginal samples, peri-partum antimicrobial therapy is advised. The changing pattern of antimicrobial resistance among GBS, particularly for macrolides/lincosamides, has implications for peri-partum antimicrobial for beta-lactam allergic patients.
MethodWe undertook a retrospective observational study at a central London teaching hospital to investigate GBS antimicrobial resistance and peri-partum prescribing between 1st April 2016 and 31st March 2019.
Results939 obstetric patients had GBS identified at Chelsea & Westminster Hospital during the study period. 31% (279(263 resistant and 16 intermediate)/900) were erythromycin resistant and 27% (246/911) clindamycin resistant. 5.6% (51/900) had incongruent erythromycin/clindamycin resistance, presumed erm mediated.
390 women received peri-partum antimicrobials for GBS. The majority of patients received benzylpenicillin therapy (70.2%, 274/390), with cefuroxime (23.1%, 90/390), clindamycin (5.6%,22/390) and teicoplanin (1%,4/390) based therapies also used. 40.9% (9/22) were given clindamycin despite known GBS resistance.
ConclusionOur data support the national guidelines, with high erythromycin/clindamycin resistance reported locally. Updated UK guidelines for GBS colonised patients recommend the use of vancomycin for beta-lactam allergic patients. Yet where sensitivities are known, clindamycin may still be used for 70% of beta-lactam allergic patients. Vancomycin, more challenging to administer and monitor, can be reserved for beta-lactam allergic, clindamycin resistant GBS carriers which account for a minority of the population (2.8%). Developing a working pathway implementation is challenging as evident with the inappropriate clindamycin use in 9 patients locally.
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Treatment Failure in a Case of Fully Susceptible Tuberculous Lymphadenitis; Time to Consider Dual Pathology
More LessBackgroundThe clinical presentation of tuberculous lymphadenitis (TBL) can mimic that of other pathologies; obtaining a tissue diagnosis is therefore essential. Dual pathology can manifest as apparent treatment failure and rare cases of coexistent lymphoma have been reported.
Case descriptionA 54-year-old fit and well man of African-Caribbean origin presented with an 8-week history of dysphagia, breathlessness and weight loss. He was tachypnoeic and thin with right supraclavicular and axillary lymphadenopathy.
An HIV test was negative. A CT thorax demonstrated clear lung fields and a 7.2cm mediastinal soft tissue mass compressing the oesophagus and trachea.
US-guided core biopsies of a supraclavicular lymph node showed necrotising granulomatous inflammation. There was no evidence of lymphoma on immunohistochemistry. An acid-fast bacillus was seen on Wade-Fite staining.
Voractiv was commenced for suspected TBL. Tissue culture subsequently grew Mycobacterium tuberculosis. Susceptibility to treatment was confirmed by whole genome sequencing.
After two months of treatment he remained symptomatic with continued weight loss. The possibility of dual pathology was considered, and the index biopsy revisited. Steroids were commenced for a possible paradoxical reaction, resulting in some initial clinical improvement.
Ten weeks into treatment, he further deteriorated requiring artificial nutrition and tracheal stenting. Repeat CT imaging showed enlargement of the mediastinal mass, now extending into the oesophageal lumen. Oesophageal biopsy demonstrated adenocarcinoma.
ConclusionsWe report a case of TBL with coexistent adenocarcinoma, which whilst rare highlights the importance of reassessment for dual pathology in cases of biopsy proven TBL that fails to respond to appropriate anti-tuberculous therapy.
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Paediatric Clostridium difficile infection: rarer than we think?
More LessBackgroundIn view of the new IDSA clinical practice guidelines, we investigated C. difficile infection (CDI) rates and performance against the key standards in our infants and immunosuppressed paediatric patients.
MethodsUsing electronic patient notes and microbiology systems, we collected data on every positive PCR result between June 2016 and March 2018 in our paediatric population. Information included risk factors, markers of severity and medical management.
Results48 samples were sent for C. difficile testing, from which 22 patients had positive results at an average age of 7.4 years. Only five samples were sent from patients under 2 year olds, of which four were PCR positive but toxin negative. Out of 22 positive patient samples, 9 were toxin positive. Risk factors for CDI included previous antibiotics or inpatient stay in the last 3 months, as well as recent PPI use. Only one patient had toxin positive CDI with severe disease. Overall the management of CDI in both toxin positive and negative patients was appropriate in terms of antibiotic choice and duration, and was tailored to specific patient circumstances. A high proportion of CDI patients were immunosuppressed or had recently undergone bone marrow transplants, but often showed no signs of severe infection (fever, raised inflammatory markers).
ConclusionThere should be a low threshold in testing patients who are immunosuppressed, as they are more likely to develop CDI. There were no toxin positive cases in patients under two years of age, which confirms that the test is not useful in this population.
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Physician-initiated HIV testing leads to missed opportunities in an East London Hospital Acute Admissions Unit
BackgroundThe United Kingdom National Guidelines for Human Immunodeficiency Virus (HIV) Testing 2008 suggest that an HIV test should be considered in all general medical admissions, when diagnosed HIV prevalence exceeds 2 in 1000 in the local population. We evaluated physician-initiated HIV testing rates in the Acute Assessment Unit of an East London hospital.
Methods
All acute presentations over one month were reviewed retrospectively, using electronic records. Patients with confirmed HIV were identified and the requested diagnostic HIV tests were measured. The number of patients with clinical indicator conditions for adult HIV infection, as defined in the United Kingdom National Guidelines for HIV Testing 2008, who did not receive appropriate testing, was calculated.
ResultsIn the cohort of 1023 patients, two patients had known HIV. 58 diagnostic HIV tests were performed, including 40 tests in patients with no clinical indicator diseases. There were five admissions with ‘AIDS-defining conditions’, all of which were pulmonary tuberculosis and four out of five (80.0%) were tested. There were 118 admissions with ‘conditions where HIV testing should be offered’, 14 of which (11.9%) were tested. All HIV tests were negative.
ConclusionPhysician-initiated HIV testing was inadequate for such a high prevalence area, even in clinical indicator diseases. Physician-initiated HIV testing should be replaced with routine opt-out HIV testing in acute medical admissions units in areas of high HIV prevalence, as suggested by BHIVA (British HIV Association) guidelines, as we progress towards ending the HIV epidemic in the United Kingdom.
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Modelling Staphylococcus aureus biofilm on infected chronic wounds
More LessChronic wounds, for instance venous, pressure, arterial and diabetic ulcers, are a major health problem throughout the world. Compared with normal wounds, those that take more than four weeks to heal are defined as chronic. Interestingly, the numbers of patients suffering from chronic wounds and the cost for treatment have been increasing during the past two decades. There is increasing evidence that suggests that bacteria infect those chronic wounds and there exist as a biofilm, which affects the wound healing and success of wound treatment. The aim of this project is to develop a dynamic ex vivomodel to mimic Staphylococcus aureus biofilm on infected chronic wound using artificial wound fluid, 3D printing and porcine skin. This dynamic model also will be used to determine drug delivery from commercial antibiotic discs and poly-ε-caprolactone (PCL) electrospun fibrous matrices. The results indicated that our new developed dynamic model was succeed with mimicking S. aureus biofilm on infected chronic wounds. Compared our flow system with traditional colony biofilm assay (CBA), it had generated an air-liquid-solid interface, which is more approach to real conditions. Meanwhile, drug delivery from PCL electrospun matrices had been tested with both CBA and flow system. The results provided further strong evidence on the benefaction of our new developed ex vivomodel. In summary, this new developed easily application model will be potentially significant on improving studying treatments of biofilms on infected chronic wounds.
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Scrub typhus causing acute undifferentiated febrile illness and its association with clinical outcomes: An observational hospital based study from tertiary care center in North India
More LessBackground: The clinical presentation of Scrub typhus mimics other acute undifferentiated febrile illnesses (AUFI) thus making it difficult to diagnose clinically.
Methods: Patients hospitalized with acute febrile illness (2-21 days) along with clinical suspicion for scrub typhus were evaluated for specific IgM antibodies against O. tsutsugamushi by ELISA and details of demographic, clinical, laboratory and clinical complication/outcomes related parameters collected for statistical analysis.
Results: Scrub typhus IgM antibodies by ELISA were detected in 88 (18.1%) patients out of 486 patients hospitalized with acute febrile illness and clinically suspected for Scrub typhus between September 2015 and January 2017. The majority sero-positive cases were found in July-December (p=0.02). Out of 88, twenty nine sero-positive Scrub typhus patients had serological evidence of co-infections. Eschar was observed in 11 (12.5%) sero-positive patients. Of 88, 23 sero-positive Scrub typhus patients died. A low platelet count (RR: 0.99; 95% CI:0.98-1.00, p=0.02), requirement of intensive care (RR: 2.26; 95% CI: 0.19-26.5, p = 0.01), need for mechanical ventilation (RR: 3.8, 95% CI: 1.35-10.86, p =0.003) and metabolic acidosis (RR: 3.47; 95% CI: 0.9-13.4, p = 0.03) were associated with mortality among sero-positive Scrub typhus patients. An appropriate antibiotic administration (n=46/88) was associated with clinical recovery/discharge (n=42/46; p=0.002).
Conclusion: Our results emphasize early diagnosis and administration of appropriate antibiotic for the management of scrub typhus in view of multiple etiologies in the initial diagnostic workup of patients presenting with AUFI. Thrombocytopenia, metabolic acidosis, need for mechanical ventilation and intensive care were associated with adverse clinical outcome among patients with Scrub typhus.
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Recurrent Urinary Tract Infections: old story, new frontiers
More LessBackgroundUrinary tract infections (UTIs) are common and frequently recur. Successful management is challenging, with UTIs responsible for 14% of community antibiotic prescriptions. Improving the management of recurrent UTIs is a national priority carrying major implications for antimicrobial stewardship.
Methods
We have introduced a multi-specialty clinic with a personalized approach to antimicrobial prescribing. Together a consultant medical microbiologist and a consultant urologist assess each patient’s pre-disposing risk factors and symptomatic burden. Anatomical and functional urological factors, and issues such as poor sample quality and lifestyle are investigated. Choice of antimicrobial agent, as well as the mode and frequency of administration, is made in accordance with patient preferences, resistance patterns, and risk factors.
Primary and secondary care data was collected for the year preceding and the year following initial clinic attendance. The impact of attendance on acute admissions, antibiotic prescribing, diagnostics utilization, and primary care workload was assessed.
ResultsWe assessed the impact of 36 clinic attendances. We noted a 91% reduction in acute admissions, a 73% drop in UTI related primary care attendances, a 57% fall in antibiotic prescriptions, and a 61% reduction in the number of MSUs sent. Qualitative data also indicates a substantial impact on patient quality of life.
ConclusionTo our knowledge we are the first center to utilize a multi-speciality recurrent UTI clinic to personalize antimicrobial and surgical therapy in tandem. Improvement in clinical outcomes is matched by reduced workload. Further study will assess long-term impact and will support regional adoption of this stratagem.
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Post-influenza meningitis in an immunosuppressed man
More LessBackground:We report a case of post-influenza invasive aspergillosis causing ventriculitis in a patient immunosuppressed on methotrexate for rheumatoid arthritis.
Summary:A 63-year-old male with a positive H1N1 throat swab presented with increasing dyspnoea and pyrexia that failed to improve despite broad-spectrum antibiotics and zanamivir. Imaging of his chest showed cavitating lung disease and a possible post influenza fungal infection. He was initiated on antifungal treatment that was stopped after 10 days following a negative bronchoalveolar lavage and serum galactomann test. Respiratory symptoms and inflammatory markers improved but he developed confusion and falls. Computed tomography of the head showed hydrocephalus but there was no papilloedema. Examination of the cerebrospinal fluid (CSF) showed lymphocytosis with elevated proteins but negative initial investigations. Subsequent magnetic resonance imaging of the head with contrast showed obstructing hydrocephalus with ventriculitis. He underwent an urgent ventriculostomy by the neurosurgeons which demonstrated purulent CSF. CSF testing was strongly positive for beta-D glucan, a positive PCR result for aspergillus in CSF was received from the initial lumbar puncture and histology from operative samples showed fungal hyphae. Dual antifungal treatment was recommenced but the patient’s conditioned worsened, and he died on ITU.
Conclusion:Whilst invasive pulmonary aspergillosis is a recognised complication of influenza, extrapulmonary infection is less well documented. This is the first case in the literature in which ventriculitis due to aspergillus is described as a sequel to infection with influenza. Clinicians should remain vigilant for fungal infection in patients with influenza who are immunosuppressed.
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Management of methicillin sensitive Staphylococcus aureus bacteraemia in an antimicrobial stewardship age
More LessBackground: Methicillin sensitive Staphylococcus aureus bacteremia (MS-SAB) is associated with significant morbidity and mortality. Long courses of intravenous antibiotics are the traditionally recommended mainstay of treatment but are often not completed in clinical practice. Shorter courses are potentially attractive from an antimicrobial stewardship and resource perspective, but require a good evidence base.
Methods: A retrospective audit of MS-SAB management within Newcastle-upon-Tyne Hospitals NHS Foundation Trust (2016-17). Laboratory database was used to identify all cases of MS-SAB. Demographic details, risk factors and management were recorded from patient records. Outcomes were defined as 90d recurrence-free survival, 30d mortality, 30-90d mortality and recurrence before 90d.
Results: A total of 281 adult cases were identified with adequate data available for review. Predictors of early (30d) mortality were: age, 71.4y vs 58y p<0.001; HAI, 21.4% vs 8.6% p=0.003; osteo-articular infections, 2.5% vs 17.1% p=0.016; but not antibiotic choice. In cases surviving 30d (n=238), median antibiotic durations were: intravenous 10d (range, 0-115), total 18d (0-316). 83% received ≥14d total, 41% received ≥14d intravenous. Receiving <9d intravenous (OR 3.33 (95%CI 1.01- 10.95) or <14d total therapy (OR 4.19 (1.37-12.84) was predictive of recurrent bacteraemia, as was non-beta-lactam therapy (16% vs 4%, p=0.006), and poor CRP response at end of intravenous therapy (68% vs 35% of peak CRP, p<0.001).
Conclusions: These data suggest lower durations (9-14d) of intravenous therapy could be safe in MS-SAB, however very short courses (<9d) are associated with worse outcomes. This new evidence helps inform guidelines, balancing optimised patient outcomes alongside improved antimicrobial stewardship.
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‘The Mould that Changed the World’: Quantitative and Qualitative Analysis of Knowledge and Behavioural Change following Participation in an Antimicrobial Resistance Musical
More LessBackground: Antimicrobial resistance (AMR) is driven by antimicrobial exposure. Engaging the general public with this issue is vital in order to shape attitudes and change behaviour. A primary school musical (‘The Mould that Changed the World’) was developed as a novel educational strategy with the explicit aim of engaging the public in the fight against AMR.
Methods: The musical was implemented in two primary schools as workshops followed by public performances. There were 166 child participants aged 9 to 11 years. Quantitative data was collected through a classroom questionnaire before the musical, two weeks after, and six months after. Qualitative data were collected through children’s focus groups before the musical and two weeks after.
Results: Knowledge of the key messages of the musical had increased two weeks after the musical (proportion test, 0.65, 0.77, p<0.001) and this gain in knowledge was sustained six months later (proportion test, 0.65, 0.82, p<0.001). Children recognised factors contributing to AMR, felt empowered to change their own health behaviours and demonstrated antimicrobial stewardship with intention to reduce antibiotic use. They suggested the musical had stimulated discussion around these topics at home. The musical was perceived as an enjoyable and memorable way to learn about AMR.
Conclusion: This study demonstrates potential for the use of musical theatre in this field as a novel device to improve long-term knowledge, change attitudes and emotionally engage the general public through children. Alongside existing interventions, it represents a further unique and valuable tool in the fight against AMR.
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Developing a quality assurance system for the use of stimulan beads in a diabetic foot clinic
More LessBackgroundDiabetic foot infections are an increasing healthcare issue and managing these infections can be difficult. A recent innovation in the way they are managed in the Hull clinic is the use of antibiotic impregnated (generally Gentamicin and Vancomycin) STIMULAN beads. Often only a couple of beads can be used in a foot wound making it a very uneconomical strategy if the beads can’t be stored and used on other wounds. There is no recommended quality assurance method provided by the manufacturers to validate this practice leading to this study.
Methods
Five beads were removed from a batch; at 1, 4, 8 and 12 week intervals for testing:
Bacterial Challenge: a 10mL spot of bead suspension was placed on Mueller Hinton seeded with Staphylococcus aureus ATCC 29213 and E. coli ATCC 25922 and incubated in Air, at 35±1ºC for 18±2hrs; zones of inhibition were read and recorded.
TDM: Vancomycin and Gentamicin levels present in each bead was established by analysing 50mL of suspension (1:5 DF) using a therapeutic drug monitoring assay.
ResultsBeads were microbiologically active for 12 weeks with no notable loss of potency.
Bacterial challenge: Staphylococcus aureus range 17-23mm, av. 20.4mm and E. coli range 11-20mm, av. 17.5mm.
TDM Assay: Vancomycin range 62.01 – 110.18 Av. 88.88mg/L, Gentamicin range 20.38 – 27.41 Av.23.20mg/L.
ConclusionQuality assurance of the STIMULAN beads can be established using standard TDM assays and microbiological activity, enabling a kit to be used for up to 12 weeks with clinical confidence.
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Chronicle of migrant hyperinfective Strongyloides stercolaris larvae and associated bacteremia in a patient suffering from Idiopathic Thrombocytopenic Purpura
More LessBackground:Strongyloidiasis is a neglected nematode infestation and can lead to hyperinfection syndrome. The onset of strongyloides hyper-infection syndrome is associated with a myriad of seemingly unrelated symptoms including diarrhoea, abdominal pain, urticaria, anaemia, sepsis and acute respiratory distress syndrome.
Case report:A 65-year-old female patient presenting with chief complaints of nausea, vomiting, abdominal cramps, diarrhea, fever and cough and was admitted to a teaching hospital on 2nd May 2019. The patient was a diagnosed case of idiopathic thrombocytopenic purpura on Azathioprine (50mg, BD) and oral corticosteroid therapy (Prednisolone 60mg, OD) and was on treatment from the same hospital. The patient developed these symptoms after 23 days of immunosuppressive therapy. Patient was continued with previous medication along with supportive management after admission. Blood and urine sample was received in the department of Microbiology on 3rd May 2019 for culture and sensitivity testing. Urine sample was sterile after 24 hours of aerobic incubation. Escherichia coli grew in blood culture and the isolate was susceptible to gentamicin, amikacin and colistin. Stool sample was received on 6th of May 2019 for routine microscopy. With wet mount preparation of stool specimen, numerous larvae of Strongyloides stercoralis were seen. Modified Ziehl-Neelsen staining was performed and oocysts of Cryptosporidium species were also seen. Wet mount preparation of sputum sample was also performed in which few larvae of S. stercoralis were seen.
Conclusion:As corticosteroid is the mainstay of treatment in idiopathic thrombocytopenic purpura an early diagnosis and prompt specific anti-parasitic therapy is required to eradicate these infections
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Development and Initial Evaluation of a national Infection Prevention and Antimicrobial Resistance programme for UK Girlguiding and Scouts
More LessBackgroundBetween 2016-18, infection prevention (IP) and antimicrobial resistance (AMR) projects were developed independently by Girlguiding and Scout groups across four UK regions. The UK 5-year AMR Action Plan outlines the importance of public engagement. This abstract describes the development, pilot and initial evaluation of a national infection prevention (IP) and AMR resource pack for Girlguiding and Scouts.
MethodsEarly 2019, PHE developed a national working-group, including local pilot individuals, and Girlguiding and Scout volunteers interested in IP and AMR to agree on the content of a national programme through a consensus approach. Summer 2019, the programme was piloted across the UK. Initial evaluation included course leader feedback and an age-appropriate survey.
ResultsThe consensus process concluded that the programme should include interactive e-Bug activities regarding microbes; hand, respiratory and food hygiene; antimicrobials and AMR. To consolidate learning, participants would create posters, make Antibiotic Guardian pledges, and share these with their families. A draft resource pack was developed to enable the programme to be delivered by leaders without a science/health background. Initial evaluation with over 150 children will be presented, to include enjoyment, acquisition of knowledge, and intentions to change health behaviours (i.e. improve hand and respiratory hygiene, and only use antibiotics when needed). Feedback from children and leaders will be used to update the resource pack prior to launch.
ConclusionThis national programme is engaging and delivers key IP and AMR messages. The programme will be launched for World Antibiotics Awareness Week 2019. Full evaluation planned for 2020.
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Endogenous endophthalmitis as a secondary bacterial infection following viral disruption of the blood-ocular barrier?Case report of 2 renal transplant patients
More LessBackground: Endogenous endophthalmitis is a rare but serious ocular infection. Seeding is usually haematogenous, and the visual prognosis is poor. We present 2 cases of bacterial endophthalmitis rapidly following viral retinitis in patients with a history of renal transplantation and no systemic symptoms of bacteraemia.
Case 1:
A 47 year old woman presented with features of bilateral panuveitis with retinitis, with no systemic symptoms.She had a history of renal transplantation. Escherichia coli had been isolated from multiple previous blood and urine cultures in the preceding months. A diagnosis of cytomegalovirus (CMV) retinitis was made on the basis of positive PCR from aqueous humour, and antiviral treatment commenced. Her left eye vision subsequently deteriorated. A repeat sample grew E. coli with a matching antibiogram to her previous isolates.
Case 2:
A 55 year old man presented with features of right-sided panuveitis and acute retinal necrosis, with no systemic symptoms. He had a history of renal transplantation. A diagnosis of varicella zoster virus (VZV) retinitis was made on the basis of positive PCR from the aqueous humour, and antiviral treatment commenced. His symptoms deteriorated, and Streptococcus pneumoniae was isolated by culture from a repeat sample. Imaging of the sinuses revealed inflammatory changes.
Conclusions:
We hypothesise that endophthalmitis in these two immunocompromised patients may have been opportunistically enabled by disruption of the blood-ocular barrier by the preceding viral infection, allowing a transient bacteraemia to seed. Whether there may be any role for prophylactic antibiotics in this context would benefit from further study.
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Brewer’s Yeast as a cause of infective endocarditis
More LessBackground: Molecular tests are increasingly used in culture negative endocarditis and may be helpful adjuncts to diagnosis; here we report the case of Saccharomyces cerevisiae mitral valve endocarditis in an immunocompetent patient.
Case History: A previously well 63 year old man presented with a ten day history of fever, nights sweats and progressive shortness of breath. On arrival, he was in acute respiratory distress, in pulmonary oedema and had a pansystolic murmur. A transoesophageal echocardiogram showed severe mitral regurgitation and a mass on the posterior leaflet of the mitral valve. He was treated for a presumed native valve endocarditis with Amoxicillin, Flucloxacillin and Gentamicin. He had a minimally invasive mitral valve repair; a vegetation was noted. All initial cultures and serologies were negative. He improved and was discharged on ceftriaxone and doxycycline on OPAT. Results three weeks post-surgery showed a Beta D Glucan of >500pg/mL (cut off 80) and an 18S PCR on the valve positive for Saccharomyces cerevisiae. No histology was available from the vegetation and fungal cultures were negative. He was much improved at that point and received 6 weeks of voriconazole to treat invasive infection; his Beta D Glucan fell to less than 30 and he was well on follow-up.
Conclusion: Saccharomyces cerevisae is an unusual cause of an endocarditis in an immunocompetent patient. This case illustrates the importance of considering non-bacterial causes of endocarditis in such cases and the utility of molecular diagnostics as adjuncts to traditional culture techniques.
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Fusobacterium nucleatum brain and liver abscesses following sigmoid diverticulum perforation in an immunocompetent patient
We report a case of disseminated Fusobacterium nucleatum likely secondary to an undiagnosed perforated sigmoid diverticulum. A 50-year old male, (past history of COPD, schizophrenia and diverticulosis) presented with fever, seizures and progressive leg weakness over 4 days. Examination revealed left leg weakness and hepatomegaly. CT-brain showed bilateral supra-tentorial lesions with sulcal effacement; MRI findings were consistent with abscesses. Initial management included burr-hole drainage of 2 intra-cranial lesions and treatment with ceftriaxone and metronidazole. The patient defervesced post-operatively.
Blood cultures (day 1) and cerebral pus (day 3) grew Fusobacterium nucleatum after 5 days. HIV Ab/Ag negative. Subsequent imaging excluded endocarditis, intra-cardiac shunting and jugular vein thrombosis. CT revealed pulmonary emboli, liver abscess (68x46x42 mm, inaccessible to drainage) and localised sigmoid perforation. Later, the patient admitted to a 5-day period of severe self-limiting abdominal pain 2-weeks prior to admission, probably relating to sigmoid perforation.
The patient required further neurosurgical drainage (day 10) due to fluctuating consciousness; intra-operative samples were culture negative. Neurological improvement occurred during 4 weeks treatment. Total antibiotic duration will be determined by follow-up imaging.
Fusobacterium spp.are fastidious Gram-negative rods. Microscopy can differentiate the main pathogenic species showing tapered ends (F. nucleatum) or pleomorphic rods (F. necrophorum). Malignancy, diabetes and immunosuppression/HIV are associated, but none are present here. Presentations include abscesses, bacteraemia, thrombophlebitis, osteomyelitis and endocarditis. This case highlights the need for early sampling, careful history regarding source, covering at least 2-4 weeks preceding presentation, and demonstrates paradoxical deterioration after antibiotics and drainage, likely due to post-treatment inflammatory reaction.
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Hepatitis E diagnostics: immunocompetent and IgM-negative implies PCR negative
More LessHepatitis E virus has, over the past few years, been increasingly recognised as a cause of acute hepatitis in the western world. The first hepatitis E Standard for Microbiology Investigations (SMI) was issued in November 2018 and recommends cascading testing in immunocompetent individuals, with RNA assays clarifying results of antibody assays. We investigated all clinical samples tested for hepatitis E in our regional laboratory between October 2014 and October 2018 (12671 IgM, 10738 IgG and 2290 RNA assays). In 495 cases, samples collected within 24 hours from a patient underwent IgM assays (DS2 platform) and PCR assays (in-house). 7 pairs, corresponding to 5 patients, of 404 pairs with negative or low-positive IgM results, had detectable RNA. 4 of those 5 patients were demonstrably immunocompromised; the final sample came from general practice without further details. 3/5 patients had reactive IgG assays, and one of the two remaining patients had a rise in IgM titre between two successive samples. We conclude that, in our sample population, hepatitis E RNA PCR testing adds minimal diagnostic information in immunocompetent individuals with negative or low-positive IgM results. This finding supports current testing cascade recommendations. We discuss our sample population’s demographics and external validity of findings: in particular, we saw few tests sent by neurologists. Finally, we briefly discuss other IgM/IgG/PCR result scenarios and our findings in relation to current SMI recommendations, and speculate how our findings affect understanding of antibody response and viraemia in hepatitis E infection.
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Is prior antibiotic exposure a risk factor for the development of bacteraemia in bone marrow transplant patients?
More LessBackground: Bone marrow transplantation (BMT) is a unique immunosuppressed state, and the consequences of infection are often severe. We hypothesized that disruption of the faecal microbiota (such as with use of broad spectrum antibiotics) may predispose to gastrointestinal related sepsis post bone marrow transplantation.
Methods: We reviewed the laboratory data from all BMT patients between January 2016 and August 2018 and recorded the presence of bacteraemia. We matched these patients to controls with no recorded bacteraemia. We then recorded antibiotic exposure in the immediate pre-transplant period.
Results: 238 records were reviewed (81 allografts, 157 autografts). We identified 28 patients with bacteraemia from gastrointestinal related pathogens. 28 controls with no positive blood cultures were matched according to the type of BMT. In both groups there were 18 allografts, 12 of which were matched unrelated donors. In the bacteraemic group there were a total of 12 antibiotic episodes (60 days) pre-transplant, compared with 6 (41 days) in the control group. The most common antibiotics used were meropenem (47 days in the bacteraemic group, 24 control) and piperacillin/tazobactan (13 days in the bacteraemic group, 3 control).
Conclusion: Our results support the hypothesis that broad spectrum antibiotics pre-transplant may predispose to post-transplant sepsis. Although the small population size limits this study, further studies are necessary to confirm this finding, and to investigate which components of the faecal microbiota are the most important to preserve prior to BMT. This may open the door to novel therapeutics in this patient group, such as faecal microbiota transplant.
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Understanding antimicrobial prescribing in suspected ventilator-associated pneumonia: a prospective cohort study
BackgroundVentilator-associated pneumonia (VAP) is associated with significant healthcare cost, morbidity, and mortality, but can be difficult to identify, resulting in over-diagnosis and excessive use of broad-spectrum antimicrobial therapy. In addition, some organisms commonly cultured from the airways of critically ill patients, in particular Candida species, are of unknown clinical significance.
Methods
A prospective cohort study was conducted across five intensive care units in the North-West of England. Participants were enrolled within 24 hours of commencing antimicrobial therapy for suspected VAP. Laboratory-confirmed VAP was defined by quantitative culture of a known pneumonia-causing pathogen above predetermined growth thresholds.
Univariate logistic regression was used to determine the impact of laboratory-confirmed VAP, APACHE II, culture of Staphylococcus aureus, and culture of Candida species on 30-day mortality.
ResultsThe prevalence of laboratory-confirmed VAP was 43/96 (44%), and the median number of antimicrobials prescribed for VAP was 1 (range: 1-4). Candida species were identified in 32/96 patients (33%).
The overall 30-day mortality was 22/96 (26%). None of the variables analysed were associated with 30-day mortality, except for culture of Candida species, which was associated with survival (odds ratio 0.26, 95% CI 0.07 to 0.98; p= 0.047).
Conclusions
Ventilator-associated pneumonia was confirmed in under half the patients commenced on antimicrobial therapy for suspected VAP, which highlights the urgent need for improved diagnostic strategies. In our clinical practice, Candida species are not treated as pathogenic in VAP, and in this study, growth of Candida species was not associated with excess 30-day mortality.
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