Pyroglutamate acidosis 2023. A review of 100 cases

This review concerns the rare, acquired, usually iatrogenic, high-anion-gap metabolic acidosis, pyroglutamic acidosis. Pyroglutamate is a derivative of the amino acid glutamate, and is an intermediate in the 'glutathione cycle', by which glutathione is continuously synthesized and broken down. The vast majority of pyroglutamic acidosis cases occur in patients on regular, therapeutic doses of paracetamol. In about a third of cases, flucloxacillin is co-prescribed. In addition, the patients are almost always seriously unwell in other ways, typically with under-nourishment of some form. Paracetamol, with underlying disorders, conspires to divert the glutathione cycle, leading to the overproduction of pyroglutamate. Hypokalaemia is seen in about a third of cases. Once the diagnosis is suspected, it is simple to stop the paracetamol and change the antibiotic (if flucloxacillin is present), pending biochemistry. N-acetyl-cysteine can be given, but while the biochemical justification is compelling, the clinical evidence base is anecdotal.

Are insect bites responsible for the rise in summer flucloxacillin prescribing in United Kingdom general practices?

BACKGROUND

Insect bite inflammation may mimic cellulitis and promote unnecessary antibiotic usage, contributing to antimicrobial resistance in primary care. We wondered how general practice clinicians assess and manage insect bites, diagnose cellulitis, and prescribe antibiotics.

METHOD

This is a Quality Improvement study in which 10 general practices in England and Wales investigated patients attending for the first time with insect bites between April and September 2021 to their practices. Mode of consultation, presentation, management plan, and reattendance or referral were noted. Total practice flucloxacillin prescribing was compared to that for insect bites.

RESULTS

A combined list size of 161,346 yielded 355 insect bite consultations. Nearly two-thirds were female, ages 3-89 years old, with July as the peak month and a mean weekly incidence of 8 per 100,000. GPs still undertook most consultations; most were phone consultations, with photo support for over half. Over 40% presented between days 1 and 3 and common symptoms were redness, itchness, pain, and heat. Vital sign recording was not common, and only 22% of patients were already taking an antihistamine despite 45% complaining of itch. Antibiotics were prescribed to nearly three-quarters of the patients, mainly orally and mostly as flucloxacillin. Reattendance occurred for 12% and referral to hospital for 2%. Flucloxacillin for insect bites contributed a mean of 5.1% of total practice flucloxacillin prescriptions, with a peak of 10.7% in July.

CONCLUSIONS

Antibiotics are likely to be overused in our insect bite practice and patients could make more use of antihistamines for itch before consulting.

It cuts both ways: A single-center retrospective review describing a three-way interaction between flucloxacillin, voriconazole and tacrolimus

AIM

Tacrolimus is a CYP3A4 substrate with a narrow therapeutic index that requires dose adjustment when used with voriconazole, a recognized CYP3A4 inhibitor. Interactions involving flucloxacillin and tacrolimus or voriconazole individually have been shown to result in decreased concentrations of the latter two drugs. Tacrolimus concentrations have been reported to be unaffected by flucloxacillin when voriconazole is administered; however, this has not been extensively investigated.

METHODS

Retrospective review of voriconazole and tacrolimus concentrations and subsequent dose adjustment following flucloxacillin administration.

RESULTS

Eight transplant recipients (five lung, two re-do lung, one heart) received concurrent flucloxacillin, voriconazole and tacrolimus. Voriconazole trough concentrations were measured before flucloxacillin initiation in three of eight patients and all trough concentrations were therapeutic. Following flucloxacillin initiation, all eight patients exhibited subtherapeutic concentrations of voriconazole (median concentration 0.15 mg/L [interquartile range (IQR) 0.10-0.28]). In five patients, voriconazole concentrations remained subtherapeutic despite dose increases, and treatment for two patients was changed to alternative antifungal agents. All eight patients required tacrolimus dose increases to maintain therapeutic concentrations after flucloxacillin initiation. Median total daily dose prior to flucloxacillin treatment was 3.5 mg [IQR 2.0-4.3] and this increased to 13.5 mg [IQR 9.5-20] (P=0.0026) during flucloxacillin treatment. When flucloxacillin was ceased, the median tacrolimus total daily dose reduced to 2.2 mg [IQR 1.9-4.7]. Supra-therapeutic tacrolimus concentrations were observed in seven patients after flucloxacillin discontinuation (median concentration 19.7 μg/L [IQR 17.9-28.0]).

CONCLUSION

A significant three-way interaction was shown between flucloxacillin, voriconazole and tacrolimus, resulting in subtherapeutic voriconazole concentrations, and requiring substantial tacrolimus dose increases. Administration of flucloxacillin to patients receiving voriconazole should be avoided. Tacrolimus concentrations should be closely monitored, and dosing adjusted during and after flucloxacillin administration.

Acute bacterial lymphadenitis in children: a retrospective, cross-sectional study

Acute bacterial lymphadenitis is a common childhood condition, yet there remains considerable variability in antibiotic treatment choice, particularly in settings with low prevalence of methicillin-resistant Staphylococcus aureus such as Europe and Australasia. This retrospective cross-sectional study reviewed children presenting with acute bacterial lymphadenitis to a tertiary paediatric hospital in Australia between 1 October 2018 and 30 September 2020. Treatment approaches were analysed with respect to children with complicated versus uncomplicated disease. A total of 148 children were included in the study, encompassing 25 patients with complicated disease and 123 with uncomplicated lymphadenitis, as defined by the presence or absence of an associated abscess or collection. In culture-positive cases, methicillin-susceptible S. aureus (49%) and Group A Streptococcus (43%) predominated, while methicillin-resistant S. aureus was seen in a minority of cases (6%). Children with complicated disease generally presented later and had a prolonged length of stay, longer durations of antibiotics, and higher frequency of surgical intervention. Beta-lactam therapy (predominantly flucloxacillin or first-generation cephalosporins) formed the mainstay of therapy for uncomplicated disease, while treatment of complicated disease was more variable with higher rates of clindamycin use.    Conclusion: Uncomplicated lymphadenitis can be managed with narrow-spectrum beta-lactam therapy (such as flucloxacillin) with low rates of relapse or complications. In complicated disease, early imaging, prompt surgical intervention, and infectious diseases consultation are recommended to guide antibiotic therapy. Prospective randomised trials are needed to guide optimal antibiotic choice and duration in children presenting with acute bacterial lymphadenitis, particularly in association with abscess formation, and to promote uniformity in treatment approaches. What is Known: • Acute bacterial lymphadenitis is a common childhood infection. • Antibiotic prescribing practices are highly variable in bacterial lymphadenitis. What is New: • Uncomplicated bacterial lymphadenitis in children can be managed with single agent narrow-spectrum beta-lactam therapy in low-MRSA prevalence settings. • Further trials are needed to ascertain optimal treatment duration and the role of clindamycin in complicated disease.

Antibiotic regimens for late-onset neonatal sepsis

BACKGROUND

Neonatal sepsis is a major cause of morbidity and mortality. It is the third leading cause of neonatal mortality globally constituting 13% of overall neonatal mortality. Despite the high burden of neonatal sepsis, high-quality evidence in diagnosis and treatment is scarce. Due to the diagnostic challenges of sepsis and the relative immunosuppression of the newborn, many neonates receive antibiotics for suspected sepsis. Antibiotics have become the most used therapeutics in neonatal intensive care units, and observational studies in high-income countries suggest that 83% to 94% of newborns treated with antibiotics for suspected sepsis have negative blood cultures. The last Cochrane Review was updated in 2005. There is a need for an updated systematic review assessing the effects of different antibiotic regimens for late-onset neonatal sepsis.

OBJECTIVES

To assess the beneficial and harmful effects of different antibiotic regimens for late-onset neonatal sepsis.

SEARCH METHODS

We searched the following electronic databases: CENTRAL (2021, Issue 3); Ovid MEDLINE; Embase Ovid; CINAHL; LILACS; Science Citation Index EXPANDED and Conference Proceedings Citation Index - Science on 12 March 2021. We also searched clinical trials databases and the reference lists of retrieved articles for randomised controlled trials (RCTs) and quasi-RCTs.

SELECTION CRITERIA

We included RCTs comparing different antibiotic regimens for late-onset neonatal sepsis. We included participants older than 72 hours of life at randomisation, suspected or diagnosed with neonatal sepsis, meningitis, osteomyelitis, endocarditis, or necrotising enterocolitis. We excluded trials that assessed treatment of fungal infections.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed studies for inclusion, extracted data, and assessed risk of bias. We used the GRADE approach to assess the certainty of evidence. Our primary outcome was all-cause mortality, and our secondary outcomes were: serious adverse events, respiratory support, circulatory support, nephrotoxicity, neurological developmental impairment, necrotising enterocolitis, and ototoxicity. Our primary time point of interest was at maximum follow-up.

MAIN RESULTS

We included five RCTs (580 participants). All trials were at high risk of bias, and had very low-certainty evidence. The five included trials assessed five different comparisons of antibiotics. We did not conduct a meta-analysis due to lack of relevant data. Of the five included trials one trial compared cefazolin plus amikacin with vancomycin plus amikacin; one trial compared ticarcillin plus clavulanic acid with flucloxacillin plus gentamicin; one trial compared cloxacillin plus amikacin with cefotaxime plus gentamicin; one trial compared meropenem with standard care (ampicillin plus gentamicin or cefotaxime plus gentamicin); and one trial compared vancomycin plus gentamicin with vancomycin plus aztreonam. None of the five comparisons found any evidence of a difference when assessing all-cause mortality, serious adverse events, circulatory support, nephrotoxicity, neurological developmental impairment, or necrotising enterocolitis; however, none of the trials were near an information size that could contribute significantly to the evidence of the comparative benefits and risks of any particular antibiotic regimen. None of the trials assessed respiratory support or ototoxicity. The benefits and harms of different antibiotic regimens remain unclear due to the lack of well-powered trials and the high risk of systematic errors.

AUTHORS' CONCLUSIONS

Current evidence is insufficient to support any antibiotic regimen being superior to another. RCTs assessing different antibiotic regimens in late-onset neonatal sepsis with low risks of bias are warranted.

Measurement of Free Plasma Concentrations of Beta-Lactam Antibiotics: An Applicability Study in Intensive Care Unit Patients

BACKGROUND

The antibacterial effect of antibiotics is linked to the free drug concentration. This study investigated the applicability of an ultrafiltration method to determine free plasma concentrations of beta-lactam antibiotics in ICU patients.

METHODS

Eligible patients included adult ICU patients treated with ceftazidime (CAZ), meropenem (MEM), piperacillin (PIP)/tazobactam (TAZ), or flucloxacillin (FXN) by continuous infusion. Up to 2 arterial blood samples were drawn at steady state. Patients could be included more than once if they received another antibiotic. Free drug concentrations were determined by high-performance liquid chromatography with ultraviolet detection after ultrafiltration, using a method that maintained physiological conditions (pH 7.4/37°C). Total drug concentrations were determined to calculate the unbound fraction. In a post-hoc analysis, free concentrations were compared with the target value of 4× the epidemiological cut-off value (ECOFF) for Pseudomonas aeruginosa as a worst-case scenario for empirical therapy with CAZ, MEM or PIP/tazobactam and against methicillin-sensitive Staphylococcus aureus for targeted therapy with FXN.

RESULTS

Fifty different antibiotic treatment periods in 38 patients were evaluated. The concentrations of the antibiotics showed a wide range because of the fixed dosing regimen in a mixed population with variable kidney function. The mean unbound fractions (fu) of CAZ, MEM, and PIP were 102.5%, 98.4%, and 95.7%, with interpatient variability of <6%. The mean fu of FXN was 11.6%, with interpatient variability of 39%. It was observed that 2 of 12 free concentrations of CAZ, 1 of 40 concentrations of MEM, and 11 of 23 concentrations of PIP were below the applied target concentration of 4 × ECOFF for P. aeruginosa. All concentrations of FXN (9 samples from 6 patients) were >8 × ECOFF for methicillin-sensitive Staphylococcus aureus.

CONCLUSIONS

For therapeutic drug monitoring purposes, measuring total or free concentrations of CAZ, MEM, or PIP is seemingly adequate. For highly protein-bound beta-lactams such as FXN, free concentrations should be favored in ICU patients with prevalent hypoalbuminemia.

[Non-Necrotizing Acute Dermo-Hypodermal Infections: Erysipela and Infectious Cellulitis]

Non-necrotizing acute dermo-hypodermal infections are infectious processes that include erysipela and infectious cellulitis, and are mainly caused by group A β-haemolytic streptococcus. The lower limbs are affected in more than 80% of cases and the risk factors are disruption of cutaneous barrier, lymphoedema and obesity. Diagnosis is clinical and in a typical setting we observe an acute inflammatory plaque with fever, lymphangitis, adenopathy and leucocytosis. Bacteriology is usually not helpful because of low sensitivity or delayed positivity. In case of atypical presentations, erysipela must be distinguished from necrotizing fasciitis and acute vein thrombosis. Flucloxacillin and cefradine remain the first line of treatment. Recurrence is the main complication, so correct treatment of the risk factors is crucial.

Effect of Vancomycin or Daptomycin With vs Without an Antistaphylococcal β-Lactam on Mortality, Bacteremia, Relapse, or Treatment Failure in Patients With MRSA Bacteremia: A Randomized Clinical Trial

IMPORTANCE

Methicillin-resistant Staphylococcus aureus (MRSA) bacteremia is associated with mortality of more than 20%. Combining standard therapy with a β-lactam antibiotic has been associated with reduced mortality, although adequately powered randomized clinical trials of this intervention have not been conducted.

OBJECTIVE

To determine whether combining an antistaphylococcal β-lactam with standard therapy is more effective than standard therapy alone in patients with MRSA bacteremia.

DESIGN, SETTING, AND PARTICIPANTS

Open-label, randomized clinical trial conducted at 27 hospital sites in 4 countries from August 2015 to July 2018 among 352 hospitalized adults with MRSA bacteremia. Follow-up was complete on October 23, 2018.

INTERVENTIONS

Participants were randomized to standard therapy (intravenous vancomycin or daptomycin) plus an antistaphylococcal β-lactam (intravenous flucloxacillin, cloxacillin, or cefazolin) (n = 174) or standard therapy alone (n = 178). Total duration of therapy was determined by treating clinicians and the β-lactam was administered for 7 days.

MAIN OUTCOMES AND MEASURES

The primary end point was a 90-day composite of mortality, persistent bacteremia at day 5, microbiological relapse, and microbiological treatment failure. Secondary outcomes included mortality at days 14, 42, and 90; persistent bacteremia at days 2 and 5; acute kidney injury (AKI); microbiological relapse; microbiological treatment failure; and duration of intravenous antibiotics.

RESULTS

The data and safety monitoring board recommended early termination of the study prior to enrollment of 440 patients because of safety. Among 352 patients randomized (mean age, 62.2 [SD, 17.7] years; 121 women [34.4%]), 345 (98%) completed the trial. The primary end point was met by 59 (35%) with combination therapy and 68 (39%) with standard therapy (absolute difference, -4.2%; 95% CI, -14.3% to 6.0%). Seven of 9 prespecified secondary end points showed no significant difference. For the combination therapy vs standard therapy groups, all-cause 90-day mortality occurred in 35 (21%) vs 28 (16%) (difference, 4.5%; 95% CI, -3.7% to 12.7%); persistent bacteremia at day 5 was observed in 19 of 166 (11%) vs 35 of 172 (20%) (difference, -8.9%; 95% CI, -16.6% to -1.2%); and, excluding patients receiving dialysis at baseline, AKI occurred in 34 of 145 (23%) vs 9 of 145 (6%) (difference, 17.2%; 95% CI, 9.3%-25.2%).

CONCLUSIONS AND RELEVANCE

Among patients with MRSA bacteremia, addition of an antistaphylococcal β-lactam to standard antibiotic therapy with vancomycin or daptomycin did not result in significant improvement in the primary composite end point of mortality, persistent bacteremia, relapse, or treatment failure. Early trial termination for safety concerns and the possibility that the study was underpowered to detect clinically important differences in favor of the intervention should be considered when interpreting the findings.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02365493.

No Fever, No Murmur, No Problem? A Concealed Case of Infective Endocarditis

BACKGROUND

Infective endocarditis is associated with significant morbidity and mortality, despite advances in diagnosis and treatment strategies. Injecting drug users are particularly at risk of endovascular infections, especially with multi-resistant and virulent microorganisms. Typically, patients with endocarditis present with constitutional symptoms, such as high fever and malaise combined with cardiorespiratory symptoms of valvular failure or emboli, such as septic pulmonary embolism.

CASE REPORT

A 33-year-old female with a history of peptic ulcer disease presented to the emergency department with 3 days of increasing unilateral calf pain and swelling. There was no history of trauma or immobilization, no fever or clinical signs of sepsis or cardiopulmonary symptoms. A history of recent i.v. amphetamine injection in the forearm was elicited and empiric treatment for endovascular infection was commenced. Workup revealed methicillin-resistant Staphylococcus aureus mitral papillary endocarditis with gastrocnemius pyomyositis, multi-joint septic arthritis, and brain abscesses. After a 60-day inpatient stay, including intensive care admission for septic shock, the patient made a good recovery. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: The incidence of injecting drug use is increasing, and these patients are at risk of severe invasive infections with multi-resistant organisms. The emergency physician is most often responsible for the initial workup and treatment of patients with suspected infective endocarditis, with timely collection of blood cultures and appropriate antibiotics being essential interventions. This case highlights that even without fever, murmurs, or constitutional symptoms, severe multisystem infections from endocarditis can occur.

Septicaemia in Patients with Temporary and Permanent Endocardial Pacemakers

Twenty-four patients with staphylococcal septicaemia due to permanent (14) and temporary (10) endocardial pacemakers were reviewed. With permanent pacemakers local inflammation was usually present and the onset of septicaemia rapid. If patients were treated with high dose intravenous flucloxacillin combined with removal, recovery was usual. In patients with retained endocardial tips (6) we eradicated infection with medical treatment alone in four cases.

We would advocate antistaphylococcal prophylaxis for patients undergoing revision in the presence of local inflammation and high dose intravenous flucloxacillin plus a second anti-staphylococcal antibiotic (e.g. gentamicin) in patients with septicaemia and a pacemaker in situ.

[Management of chronic osteomyelitis by long-term antibiotic suppression]

Chronic osteomyelitis is a chronic inflammatory disease induced by bone infection. It may be limited to a single portion of bone or involve several areas such as marrow, cortical, periosteum and adjacent soft tissues. Being able to persist for weeks, months or even years, it remains a therapeutic challenge in spite of the important medical and surgical advances, with a prolonged and complex management given the nature of the surgical interventions and the antibiotherapies required. We report a case of chronic osteomyelitis treated by long-term suppressive antibiotic therapy, which may be a reasonable alternative to surgery in inoperable clinical situations, but taking into account the risks associated with it in terms of side effects and selection of resistant organisms, as well as the cost of treatment and the quality of life of the patient.

Adjunctive clindamycin for cellulitis: a clinical trial comparing flucloxacillin with or without clindamycin for the treatment of limb cellulitis

OBJECTIVE

To compare flucloxacillin with clindamycin to flucloxacillin alone for the treatment of limb cellulitis.

DESIGN

Parallel, double-blinded, randomised controlled trial.

SETTING

Emergency department attendances and general practice referrals within 20 hospitals in England.

INTERVENTIONS

Flucloxacillin, at a minimum of 500 mg 4 times per day for 5 days, with clindamycin 300 mg 4 times per day for 2 days given orally versus flucloxacillin given alone.

MAIN OUTCOME MEASURES

The primary outcome was improvement at day 5. This was defined as being afebrile with either a reduction in affected skin surface temperature or a reduction in the circumference of the affected area. Secondary outcomes included resolution of systemic features, resolution of inflammatory markers, recovery of renal function, reduction in the affected area, decrease in pain, return to work or normal activities and the absence of increased side effects.

RESULTS

410 patients were included in the trial. No significant difference was seen in improvement at day 5 for flucloxacillin with clindamycin (136/156, 87%) versus flucloxacillin alone (140/172, 81%)-OR 1.55 (95% CI 0.81 to 3.01), p=0.174. There was a significant difference in the number of patients with diarrhoea at day 5 in the flucloxacillin with clindamycin allocation (34/160, 22%) versus flucloxacillin alone (16/176, 9%)-OR 2.7 (95% CI 1.41 to 5.07), p=0.002. There was no clinically significant difference in any secondary outcome measures. There was no significant difference in the number of patients stating that they had returned to normal activities at the day 30 interview in the flucloxacillin with clindamycin allocation (99/121, 82%) versus flucloxacillin alone (104/129, 81%)-adjusted OR 0.90 (95% CI 0.44 to 1.84).

CONCLUSIONS

The addition of a short course of clindamycin to flucloxacillin early on in limb cellulitis does not improve outcome. The addition of clindamycin doubles the likelihood of diarrhoea within the first few days.

TRIAL REGISTRATION NUMBER

NCT01876628, Results.

Staphylococcal species heterogeneity in the nasal microbiome following antibiotic prophylaxis revealed by tuf gene deep sequencing

BACKGROUND

Staphylococci are a major constituent of the nasal microbiome and a frequent cause of hospital-acquired infection. Antibiotic surgical prophylaxis is administered prior to surgery to reduce a patient's risk of postoperative infection. The impact of surgical prophylaxis on the nasal staphylococcal microbiome is largely unknown. Here, we report the species present in the nasal staphylococcal microbiome and the impact of surgical prophylaxis revealed by a novel culture independent technique. Daily nasal samples from 18 hospitalised patients, six of whom received no antibiotics and 12 of whom received antibiotic surgical prophylaxis (flucloxacillin and gentamicin or teicoplanin +/- gentamicin), were analysed by tuf gene fragment amplicon sequencing.

RESULTS

On admission to hospital, the species diversity of the nasal staphylococcal microbiome varied from patient to patient ranging from 4 to 10 species. Administration of surgical prophylaxis did not substantially alter the diversity of the staphylococcal species present in the nose; however, surgical prophylaxis did impact on the relative abundance of the staphylococcal species present. The dominant staphylococcal species present in all patients on admission was Staphylococcus epidermidis, and antibiotic administration resulted in an increase in species relative abundance. Following surgical prophylaxis, a reduction in the abundance of Staphylococcus aureus was observed in carriers, but not a complete eradication.

CONCLUSIONS

Utilising the tuf gene fragment has enabled a detailed study of the staphylococcal microbiome in the nose and highlights that although there is no change in the heterogeneity of species present, there are changes in abundance. The sensitivity of the methodology has revealed that the abundance of S. aureus is reduced to a low level by surgical prophylaxis and therefore reduces the potential risk of infection following surgery but also highlights that S. aureus does persist.

Staphylococcus aureus bacteremia with iliac artery endarteritis in a patient receiving ustekinumab

BACKGROUND

Ustekinumab (Stelara®), a human monoclonal antibody targeting the p40-subunit of interleukin (IL)-12 and IL-23, is indicated for moderate to severe plaque psoriasis and psoriatic arthritis. In large multicenter, prospective trials assessing efficacy and safety of ustekinumab increased rates of severe infections have not been observed so far.

CASE PRESENTATION

Here, we report the case of a 64-year old woman presenting with chills, pain and swelling of her right foot with dark maculae at the sole, and elevated inflammatory markers. She had received a third dose of ustekinumab due to psoriatic arthritis three days before admission. Blood cultures revealed growth of Staphylococcus aureus and imaging showed a thickening of the aortic wall ventral the bifurcation above the right internal iliac artery, resembling an acute bacterial endarteritis. Without the evidence of aneurysms and in absence of foreign bodies, the decision for conservative management was made. The patient received four weeks of antibiotic therapy with intravenous flucloxacillin, followed by an oral regime with levofloxacin and rifampicin for an additional four weeks. Inflammatory markers resolved promptly and the patient was discharged in good health.

CONCLUSION

To our knowledge, this is the first report of a severe S. aureus infection in a patient receiving ustekinumab. Albeit ustekinumab is generally regarded as a safe drug, severe bacterial infections should always be included in the differential diagnosis of elevated inflammatory markers in patients receiving biologicals as these might present with nonspecific symptoms and fever might be absent. Any effort to detect deep-seated or metastatic infections should be made to prevent complications and to secure appropriate treatment. Although other risk factors for an invasive staphylococcal infection like psoriasis, recent corticosteroid injection, or prior hospitalisations were present, and therefore a directive causative link between the S. aureus bacteraemia and ustekinumab can not be drawn, we considered the reporting of this case worthwhile to alert clinicians as we believe that ongoing pharmacovigilance to detect increased risks for rare but severe infections beyond phase II and phase III trials in patients treated with biologicals is essential.

The Role of Antibiotic Prophylaxis in Clean Incised Hand Injuries: A Prospective Randomized Placebo Controlled Double Blind Trial

A prospective, randomized, double blind, placebo controlled trial was designed to investigate the effect of prophylactic flucloxacillin on the infection rate in clean incised hand injuries, which included trauma to skin, tendon and nerve in adults. Using strict exclusion criteria, a total of 170 patients were recruited into one of three trial groups; Group A – intravenous flucloxacillin on induction followed by an oral placebo; Group B – intravenous flucloxacillin on induction followed by an oral flucloxacillin course or Group C – oral placebo. Thirteen of the patients were subsequently withdrawn, leaving 92% available to complete the trial. Infection was diagnosed using clinical criteria. The infection rates in the three groups were Group A – 13%, Group B – 4% and Group C – 15%. Strictly, the results demonstrate no statistically significant difference in the infection rates between the groups.

Osteomyelitis complicating pyomyositis in HIV disease

Pyomyositis has previously been described in association with human immunodeficiency virus (HIV) and as a discrete entity in HIV seronegative patients from tropical climates (tropical pyomyositis). Pyomyositis and osteomyelitis are usually considered a late complication of advanced HIV disease. We describe a patient with well-controlled HIV and both types of musculoskeletal infection. The case highlights an unusual presentation, the utility of MRI in soft tissue infection and an excellent outcome from prolonged antimicrobial therapy following surgical debridement.

[Community-acquired pneumonia in the elderly]

We report the case of a 88 years old patient with cough and new onset confusion. Delirium was caused by a necrotizing Methicillin-sensible staphylococcus aureus pneumonia with bacteremia. Despite antibiotic therapy for several weeks and fall of inflammatory markers the patient died from consequences of delirium.

Cellulitis: Home Or Inpatient in Children from the Emergency Department (CHOICE): protocol for a randomised controlled trial

INTRODUCTION

Children needing intravenous antibiotics for cellulitis are usually admitted to hospital, whereas adults commonly receive intravenous treatment at home. This is a randomised controlled trial (RCT) of intravenous antibiotic treatment of cellulitis in children comparing administration of ceftriaxone at home with standard care of flucloxacillin in hospital. The study aims to compare (1) the rate of treatment failure at home versus hospital (2) the safety of treatment at home versus hospital; and (3) the effect of exposure to short course ceftriaxone versus flucloxacillin on nasal and gut micro-organism resistance patterns and the clinical implications.

INCLUSION CRITERIA

children aged 6 months to <18 years with uncomplicated moderate/severe cellulitis, requiring intravenous antibiotics.

EXCLUSIONS

complicated cellulitis (eg, orbital, foreign body) and immunosuppressed or toxic patients. The study is a single-centre, open-label, non-inferiority RCT. It is set in the emergency department (ED) at the Royal Children's Hospital (RCH) in Melbourne, Australia and the Hospital-in-the-Home (HITH) programme; a home-care programme, which provides outreach from RCH. Recruitment will occur in ED from January 2015 to December 2016. Participants will be randomised to either treatment in hospital, or transfer home under the HITH programme. The calculated sample size is 188 patients (94 per group) and data will be analysed by intention-to-treat.

PRIMARY OUTCOME

treatment failure defined as a change in treatment due to lack of clinical improvement according to the treating physician or adverse events, within 48 h

SECONDARY OUTCOMES

readmission to hospital, representation, adverse events, length of stay, microbiological results, development of resistance, cost-effectiveness, patient/parent satisfaction. This study has started recruitment.

ETHICS AND DISSEMINATION

This study has been approved by the Human Research Ethics Committee of the RCH Melbourne (34254C) and registered with the ClinicalTrials.gov registry (NCT02334124). We aim to disseminate the findings through international peer-reviewed journals and conferences.

CLINICAL TRIAL

Pre-results.

Paediatric empyema in New Zealand: a tale of two cities

AIMS

We aimed to identify the causative organisms and sensitivities in community-acquired paediatric empyema at Starship Children's Hospital and Christchurch Hospital and to determine if current antibiotic recommendations are appropriate.

METHODS

Retrospective analysis was undertaken of all cases with clinical, radiological, and microbiological evidence of empyema at Starship Children's Hospital and Christchurch Hospital between June 2009 and March 2013 (3.8 years), and January 2009 and May 2014 (5.4 years) respectively.

RESULTS

Ninety-eight children were managed with empyema at Starship Children's Hospital and 30 children at Christchurch Hospital. Staphylococcus aureus was the most common pathogen identified at both sites followed by Streptococcus pneumoniae. A significant proportion had no pathogen identified. Amongst S.aureus isolates, 1/5th were methicillin-resistant, contributing 8% of all culture positive empyema cases. Māori and Pacific groups were over-represented. Cases occurred more often in boys and those <5 years. Blood cultures and S.pneumoniae pleural antigen were important in diagnosis.

CONCLUSIONS

Our audit confirms the important role of S.aureus in paediatric empyema in New Zealand and a high rate of this disease, particularly in the North Island. Antimicrobial susceptibilities of the pathogens of empyema demonstrate current initial antibiotic recommendation.

[Severe osteoarticular infections with Staphylococcus aureus producer of Panton-Valentine Leukocidine in children]

Emerging strain of Stapylococcus aureus (S. aureus) producer of the Panton-Valentine Leukocidine (PVL+) are becoming a new issue in public health. Those bacteria are accountable for serious cutaneous infection with a necrotic evolution, necrotizing pneumonia and severe osteoarticular infection. These last infections can be life-threatening and are at high risk of complications. Therefore, a multidisciplinary approach is necessary, in addition with an aggressive chirurgical treatment. We are here reporting 3 cases of osteoarticular infections by S. aureus PVL+ sensitive to methicilline, which illustrate the difficulties encountered in the management and treatment, as well as the potential for serious orthopedics complications.

[Convulsions due to an interaction between anti-epileptic drugs and rifampicin]

BACKGROUND

Anti-epileptic drugs (AEDs) have a small therapeutic window, so it is important to monitor plasma levels. Inadequate plasma levels may lead to convulsions. Many AEDs are cleared hepatically, and there are many drug interactions that are known to lead to changes in plasma levels.

CASE DESCRIPTION

A 54-year-old woman with known epilepsy developed convulsions after using rifampicin and flucloxacillin, despite the use of maintenance treatment in the form of carbamazepine, valproic acid and clonazepam. Since rifampicin is known to induce several cytochrome P450 enzymes and clearance of the anti-epileptic drug used may be affected by this, it can be assumed that the convulsions were caused by rifampicin. This interaction is however not mentioned in the Dutch 'G-standard' database.

CONCLUSION

Rifampicin is known to be a strong inducer of various cytochrome P450 enzymes. This case description shows that the use of rifampicin may lead to convulsions. For this reason, these interactions should be included in the Dutch G-standard database.

Secondary bilateral striopallidodentate calcinosis associated with generalized pustular psoriasis (Von Zumbusch)

Bilateral striopallidodentate calcinosis (BSPDC) mentioned in the literature as Fahr's disease (a misnomer), is characterized by symmetrical and bilateral intracerebral calcifications located in the basal ganglia with or without deposits in the dentate nucleus, thalamus, and white matter. This entity is usually asymptomatic but may be manifested by neurological symptoms. Idiopathic BSPDC can occur either as sporadic or autosomal dominant familial forms. Secondary presentations of BSPDC are associated with infections, neoplastic diseases, toxicological or traumatic factors, and metabolic disorders. We describe a case of generalized pustular psoriasis associated with secondary BSPDC owing to pseudohypoparathyroidism. Laboratory tests revealed hypocalcemia, hyperphosphatemia, and a normal serum level of parathormone. The correction of the phosphorus-calcium metabolism disorder produced clinical improvement.

Problem based review: The patient with acute monoarthritis

Acute monoarthritis is a common medical emergency with wide differential diagnosis. Common underlying causes include trauma, septic arthritis, crystal induced arthritis (gout and pseudogout), and reactive arthritis. Of these, septic arthritis is the diagnosis not to miss because of its association with significant morbidity and mortality. Precise diagnosis of the underlying cause of monoarthritis relies on a good history, physical examination findings, and results of focussed investigations. In this article, a practical approach to diagnosis and initial management of patients presenting with acute monoarthritis is described with the aid of a case vignette.

[A girl with a painful red skin]

A 5-year-old girl presented with increasing erythroderma since one day in combination with impetigo vulgaris. As exfoliative lesions and bullae developed within hours, the patient was diagnosed with staphylococcal scalded skin syndrome. She was successfully treated with flucloxacillin.

[Acute skin detachment in a newborn]

Acute blistering and erosion in a newborn is one of the few emergency cases seen in dermatology. It is important to differentiate between infectious causes, congenital abnormalities, autoimmune bullous dermatitis, immunological skin diseases and skin burns within 24 hours. In this clinical lesson, we present a case of acute skin detachment in a newborn caused by staphylococcal scalded skin syndrome (SSSS). Our patient was a six-day-old boy who had developed flaccid blisters around the umbilicus, which ruptured on minimal friction. Generalised superficial erosions on the face, hands and feet arose within hours. Based on the clinical presentation combined with a subcorneal blister found on histopathological examination and a positive culture for Staphylococcus aureus on nasal and umbilical smears, the diagnosis of SSSS was made. Our patient was treated successfully with flucloxacillin and gentamicin; the skin lesions healed without scarring within six days.

Pyomyositis

Poorly controlled diabetes is associated with an increased risk of infectious complications. With the increasing prevalence of diabetes, many more people are being looked after in primary care. We describe a case of pyomyositis, a potentially severe but uncommon complication of poorly controlled diabetes that was not recognised in the community. Clinicians looking after people with diabetes need to be aware that prolonged, unexplained symptoms need specialist assessment.

[Peripheral intravenous catheter-related phlebitis]

Phlebitis is a very common complication of the use of intravenous catheters. Two patients with an i.v. catheter complicated by thrombophlebitis are described. Patient A was immunocompromised due to chronic lymphatic leukaemia and developed septic thrombophlebitis with positive blood cultures for S. Aureus. Patient B was being treated with flucloxacillin because of an S. Aureus infection and developed chemical phlebitis. Septic phlebitis is rare, but potentially serious. Chemical or mechanical types of thrombophlebitis are usually less severe, but happen very frequently. Risk factors include: female sex, previous episode of phlebitis, insertion at (ventral) forearm, emergency placement and administration of antibiotics. Until recently, routine replacement of peripheral intravenous catheters after 72-96 h was recommended, but randomised controlled trials have not shown any benefit of this routine. A recent Cochrane Review recommends replacement of peripheral intravenous catheters when clinically indicated only.

How immunocompromised are short bowel patients receiving home parenteral nutrition? Apropos a case of disseminated Fusarium oxysporum sepsis

BACKGROUND

Catheter-related sepsis is the most frequent complication in patients receiving home parenteral nutrition (HPN) for short bowel syndrome (SBS). A low-grade systemic inflammatory state and an altered mucosal immune response, as well as diminished intestinal barrier function have been characterized in these patients. The possibility of systemic immunocompromise has only recently been suggested.

CASE DESCRIPTION

A 45-year-old female with traumatic SBS was admitted for possible catheter-related sepsis. She was asplenic and had insulin-dependent diabetes mellitus as a result of a pancreatic resection. A large skin ulceration was present on her left calf, which appeared unusual for a disseminated bacterial infection. Chest x-ray and computed tomography scan revealed multiple subpleural pulmonary infiltrates consistent with bacterial or fungal dissemination. Blood cultures from the port system and from the peripheral blood grew Staphylococcus haemolyticus and Fusarium oxysporum. The port system was removed, and flucloxacillin and voriconazole were given for 33 and 35 days, respectively. Clinical signs of disseminated sepsis resolved slowly. Bone marrow biopsy ruled out primary hematologic disease.

CONCLUSIONS

(1) Catheter-related sepsis in patients on HPN is usually caused by Gram-positive or Gram-negative bacteria or by Candida species. Identification of molds in blood cultures strongly suggests Fusarium species, which should be treated appropriately with voriconazole or amphotericin B. (2) HPN and SBS aggravated by asplenism and diabetes mellitus can cause severe immunocompromise. (3) Fusaria have a strong tendency to persist or reappear after bone marrow transplantation, which is therefore relatively contraindicated in these patients.

Non-contiguous multifocal Staphylococcus aureus discitis: involvement of the cervical, thoracic and lumbar spine

INTRODUCTION

Multilevel discitis is rare, and classically due to granulomatous organisms like Mycobacterium tuberculosis, brucella and fungal species.

CONCLUSION

We report a case of non-contiguous multilevel synchronous bacterial discitis involving cervical, thoracic and lumbar discs, attributable to Staphylococcus aureus.

Acute suppurative neonatal parotitis: Case report

Neonatal suppurative parotitis is very rare. One review of the English-language literature spanning 35 years found only 32 cases. Most cases are managed conservatively with antibiotic therapy; early antibiotic treatment reduces the need for surgery. The predominant organism is Staphylococcus aureus. We report a new case of neonatal suppurative parotitis in a 3-week-old boy. The patient was diagnosed on the basis of parotid swelling, a purulent exudate from a Stensen duct, and the growth of pathogenic bacteria in culture. He responded well to 9 days of intravenous antibiotic therapy. We also discuss the microbiologic and clinical patterns of this disease.

Septic trochanteric bursitis in an adolescent

Trochanteric bursitis, whether septic or inflammatory in origin, is a condition that affects middle-aged patients. Here we report the rare case of an adolescent with septic trochanteric bursitis (treated successfully with intravenous antibiotics), review the available literature on septic bursitis, illustrate the importance of prompt recognition and treatment of this condition in any age group, and describe the clinical presentation and the radiologic findings.

Furuncular myiasis: unusual case of African Dermatobia hominis

Human cutaneous myiasis is a common disease in endemic tropical zones. Increased international travel has produced increases in imported cases. We present an unusual patient with myiasis infestation of the leg caused by Dermatobia hominis, which manifested after returning from the Democratic Republic of Congo. This particular infestation has not been reported in Morocco prior to this case. Furuncular cutaneous miyasis must be considered when travellers exhibit draining nodules. Medical treatment consists of occlusion of the furuncular punctum with vaseline to stimulate extrusion of the larva or surgical debridement under local anesthesia.

Panton Valentine leukocidin MSSA leading to multi-organ failure

We report a case of a 15-year-old boy who developed multiple organ failure secondary to a sport injury leading to infection with a Panton Valentine Leukocidin (PVL) secreting Community-Acquired Methicillin Sensitive Staphylococcus Aureus (CA MSSA). Aggressive antibiotic therapy eventually led to recovery.

Necrotizing black tattoo reaction: what's in a name?

We report the rare case of an 18-year-old man who developed a necrotizing cutaneous reaction 5 days after having a permanent black tattoo on his left forearm spelling his name. Three cases of reactions to permanent black tattoos have been reported within the literature. These cases described the development of cellulitis of the skin adjacent to the tattoo but none reported florid necrotizing cutaneous reactions. The initial management with oral antibacterials failed to resolve the symptoms and use of intravenous antibacterials and topical corticosteroids was needed. Six weeks after presentation the tattoo lettering showed the presence of hyperpigmented skin. Subsequent patch testing confirmed that the patient had no allergy to black tattoo pigments suggesting that the necrotizing cutaneous reaction was secondary to infection. We show that successful treatment of this rare infective complication of permanent black tattoos involves the early institution of intravenous antibacterial agents and topical corticosteroids.

Microanalysis of amoxicillin, flucloxacillin, and rifampicin in neonatal plasma

Simple and rapid reversed-phase high-performance liquid chromatographic assays with ultraviolet detection have been developed and validated for the determination of amoxicillin, flucloxacillin and rifampicin in neonatal plasma. Plasma samples were either precipitated with perchloric acid (amoxicillin) or methanol (rifampicin) or extracted with methylene chloride (flucloxacillin). Precision coefficients of variation and inaccuracy were less than 15% for all three assays. Only small sample volumes (20-40 microL) were required, making the assays suitable for therapeutic drug monitoring and pharmacokinetic studies in preterm and term neonates. The assays have successfully been applied to analysis of amoxicillin, flucloxacillin and rifampicin in previously published pharmacokinetic studies in neonates.

Kaposi varicelliform eruption (eczema herpeticum)

A 35-year-old woman with a history of atopic diathesis presented to the emergency department with 2 weeks of widespread facial vesiculopustules and eroded vesicles. HSV-1 was found on viral culture and direct fluorescent antibody testing. She was diagnosed with eczema herpeticum, an uncommon and potentially life-threatening viral infection that arises in areas of pre-existing dermatosis. Antiviral treatment for eczema herpeticum is very effective, and should be instituted without delay to avoid significant morbidity and mortality.

The design, characteristics and predictors of mortality in the North of England Cellulitis Treatment Assessment (NECTA)

AIMS

Cellulitis is a common cause of acute medical admissions in UK hospitals. The factors that determine susceptibility to an acute admission or to mortality following hospital admission are poorly defined.

METHODS

We studied a retrospective cohort of 568 patients with a diagnosis of cellulitis between 1 January 2001 and 31 December 2003 in the north-east of England to see whether we could determine these factors. We collected data on the factors that were associated with acute hospital admissions and survival. We used a primary end-point of deaths within 1 year of admission for cellulitis.

RESULTS

The characteristics that identified patients at high risk of mortality were present in 39.9% of the cohort studied. The four most common of these characteristics were lower limb oedema 30.1% (95% CI: -26.0 to 34.1), ulceration 24% (95% CI: -20.2 to 27.8), previous myocardial infarction (MI) 19.9% (95% CI: -16.3 to 23.4) and blunt injury 18.7% (95% CI: -15.3 to 22.2). Significant predictors of mortality were: patient's age (p < 0.001), presence of penetrating injury (p < 0.001), previous MI (p < 0.001), presence of liver disease (p = 0.003), presence of lower limb oedema (p = 0.01) and long-term use of drugs that caused sodium and water retention (p < 0.001). Treatment with i.v. flucloxacillin was found to be a significant predictor of survival (odds ratio = 3.43, z =3.42. p < 0.001) at 360 days.

CONCLUSION

Our results show that cellulitis as a cause of an acute medical admission may present with a variety of clinical features. Some of these clinical features can be used to predict mortality within 360 days of an acute hospital admission.

Scalp demodicidosis mimicking favus in a 6-year-old boy

Demodex folliculorum and Demodex brevis are obligatory ectoparasites of the pilosebaceous unit in humans. Although most people are infested with these mites, only a small number develop clinical symptoms of demodicidosis. We report a case of demodicidosis in a 6-year-old boy who had lesions on the scalp, forehead, neck, and anterior chest for 18 months. Our clinical diagnosis at the time was favus. The microscopic examination of the hair in a 10% potassium hydroxide preparation showed no fungal spores or hyphae, but many eggs and adult mites of D folliculorum. The patient was treated with oral ivermectin and topical permethrin, and the lesions resolved completely. Demodicidosis is a rare disease that can clinically mimic favus and other crusted scalp dermatoses in children.

Flucloxacillin treatment of Staphylococcus aureus meningitis

In this paper, we aimed to evaluate the efficacy of flucloxacillin treatment of meningitis caused by methicillin-sensitive Staphylococcus aureus. We identified 33 patients with meningitis due to S. aureus; eight had community-acquired meningitis and 25 had neurosurgical meningitis. Six of the eight patients with community-acquired meningitis were cured. Eighteen of the 22 patients treated with flucloxacillin were cured without relapse (86%, 95%CI 65-97%) and their cerebrospinal fluid (CSF) cultures were sterile after a median of 3 days of treatment. The cure rate for 12 patients who also received an additional antibiotic at the outset of treatment was 75% (95%CI 43-95%). This was not different to the cure rate for the ten patients who received flucloxacillin alone 90% (95%CI 56-100%). We conclude that flucloxacillin is an effective treatment for meningitis caused by S. aureus.

Protein Binding of Flucloxacillin in Neonates

The isoxazolyl penicillins, including flucloxacillin, have the highest levels of plasma protein binding among the semisynthetic penicillins. Because only the free fraction of the penicillin is pharmacologically active, it would be useful to measure both protein-bound and free flucloxacillin to determine its protein binding. Until now, flucloxacillin protein binding in newborn infants has been investigated in only two studies with relatively small populations. In the present study, flucloxacillin protein binding was investigated in 56 (preterm) infants aged 3 to 87 days (gestational age, 25-41 weeks). Surplus plasma samples from routine gentamicin assays of each infant were collected and combined to obtain a sufficiently large sample for analysis. Free flucloxacillin was separated from protein-bound flucloxacillin using ultrafiltration. Reversed-phase high-performance liquid chromatography with ultraviolet detection was used to measure free flucloxacillin concentrations in ultrafiltrate and total flucloxacillin concentrations in pooled plasma. Flucloxacillin protein binding was 74.5% +/- 13.1% (mean +/- standard deviation) with a high variability among the infants (34.3% to 89.7%). High Pearson correlations were found between protein binding and the covariates-plasma albumin concentration (r = 0.804, P < 0.001, n = 18) and plasma creatinine concentration (r = -0.601, P < 0.001, n = 45). Statistically significant but less striking correlations were found between protein binding and gestational age, postconceptional age, body weight, and triglyceride concentration. Because of the high variability of protein binding among infants, it is difficult to devise a flucloxacillin dosage regimen effective for all infants. Individualized dosing, based on free flucloxacillin concentrations, might help to optimize treatment of late-onset neonatal sepsis, but practical obstacles will probably prevent analysis of free flucloxacillin concentrations in newborn infants on a routine basis.

Anterior necrotizing scleritis after strabismus surgery in a child

Anterior necrotizing scleritis is a rare but potentially devastating complication of ocular surgery that most often occurs after cataract surgery in elderly patients who may have an underlying systemic autoimmune condition(1) or, less likely, an infectious cause.(2) We describe the management and outcome of a case of bilateral anterior necrotizing scleritis after postoperative infection in a 19-month-old girl who had recently undergone strabismus surgery.

Successful treatment of a large choroidal abscess in an immunocompetent child. Treatment of a choroidal abscess

BACKGROUND

We report the case of a systemically well 4-year-old Aboriginal boy who developed a choroidal abscess after being poked in the left eye with a blunt object.

CASE REPORT

This boy presented with redness and reduced vision in the left eye after a blunt object was poked into his eye by his sibling. He was noted to have a choroidal mass which finally manifested as a choroidal abscess.

RESULTS

His initial visual acuity was 6/60, and dilated fundus examination demonstrated a localised solid-appearing choroidal elevation involving the posterior pole, including the macula. An ultrasound of the eye revealed a choroidal haematoma with an atypical appearance, whose height was 8 mm with a base of 12 mm x 10 mm. The lesion failed to resolve, and eventually resulted in orbital cellulitis that did not respond to intravenous and topical antibiotic treatment. He then went on to achieve complete visual recovery after successful management by transcleral incision, drainage and systemic antibiotic therapy.

CONCLUSION

Choroidal abscess has been described in patients who are debilitated, immunocompromised or suffer with systemic disease such as cystic fibrosis or endocarditis. This case represents a unique report of staphylococcal choroidal abscess in a healthy child that completely resolved after transcleral drainage and systemic antibiotics.