Bacteriophages for the treatment of pseudomonas-infected vascular prosthesis

We present a case report detailing therapeutic application of two lytic antipseudomonal bacteriophages to treat a chronic relapsing Pseudomonas aeruginosa infection of a prosthetic aortic graft. As there are currently no Danish laboratories offering phages for clinical therapy, and this case, to our knowledge represents the first applied phage therapy in Denmark, the practical and regulatory aspects of offering this treatment option in Denmark is briefly reviewed along with the clinical case.

Ramsay Hunt syndrome and concurrent varicella-zoster virus meningitis in Denmark: A nationwide cohort study

Ramsay Hunt syndrome (RHS) is a manifestation of reactivated varicella-zoster virus (VZV) from the geniculate ganglion. Data on clinical features and outcomes of patients with RHS and concurrent VZV meningitis (henceforth RHS meningitis) are limited. Thus, we conducted a nationwide population-based cohort study of all adults hospitalized for RHS meningitis at the departments of infectious diseases in Denmark from 2015 to 2020. Patients with VZV meningitis without cranial nerve palsies were included for comparison. In total, 37 patients with RHS meningitis (mean annual incidence: 1.6/1 000 000 adults) and 162 with VZV meningitis without cranial nerve palsies were included. In RHS meningitis, the median age was 52 years (interquartile range: 35-64), and in addition to peripheral facial nerve palsy (100%), dizziness (46%), and hearing loss (35%) were common symptoms. The triad of headache, neck stiffness, and photophobia/hyperacusis was less common in RHS meningitis than in VZV meningitis without cranial nerve palsies (0/27 [0%] vs. 24/143 [17%]; p = 0.02). At 30 days after discharge, 18/36 (50%) patients with RHS meningitis had persistent peripheral facial nerve palsy, with no statistically significant difference between those treated with and without adjuvant glucocorticoids (6/16 [38%] vs. 12/20 [60%]; p = 0.18). Additional sequelae of RHS meningitis included dizziness (29%), neuralgia (14%), tinnitus/hyperacusis (11%), hearing loss (9%), headache (9%), fatigue (6%), and concentration difficulties (3%). In conclusion, clinical features and outcomes of RHS meningitis were primarily related to cranial neuropathies.

Understanding the treatment benefit of hyperimmune anti-influenza intravenous immunoglobulin (Flu-IVIG) for severe human influenza

BACKGROUNDAntibody-based therapies for respiratory viruses are of increasing importance. The INSIGHT 006 trial administered anti-influenza hyperimmune intravenous immunoglobulin (Flu-IVIG) to patients hospitalized with influenza. Flu-IVIG treatment improved outcomes in patients with influenza B but showed no benefit for influenza A.METHODSTo probe potential mechanisms of Flu-IVIG utility, sera collected from patients hospitalized with influenza A or B viruses (IAV or IBV) were analyzed for antibody isotype/subclass and Fcγ receptor (FcγR) binding by ELISA, bead-based multiplex, and NK cell activation assays.RESULTSInfluenza-specific FcγR-binding antibodies were elevated in Flu-IVIG-infused IBV- and IAV-infected patients. In IBV-infected participants (n = 62), increased IgG3 and FcγR binding were associated with more favorable outcomes. Flu-IVIG therapy also improved the odds of a more favorable outcome in patients with low levels of anti-IBV Fc-functional antibody. Higher FcγR-binding antibody was associated with less favorable outcomes in IAV-infected patients (n = 50), and Flu-IVIG worsened the odds of a favorable outcome in participants with low levels of anti-IAV Fc-functional antibody.CONCLUSIONThese detailed serological analyses provide insights into antibody features and mechanisms required for a successful humoral response against influenza, suggesting that IBV-specific, but not IAV-specific, antibodies with Fc-mediated functions may assist in improving influenza outcome. This work will inform development of improved influenza immunotherapies.TRIAL REGISTRATIONClinicalTrials.gov NCT02287467.FUNDINGFunding for this research was provided by subcontract 13XS134 under Leidos Biomedical Research Prime Contract HHSN261200800001E and HHSN261201500003I, NCI/NIAID.

Noninvasive intracranial pressure monitoring in central nervous system infections

Intracranial pressure (ICP) monitoring constitutes an important part of the management of traumatic brain injury. However, its application in other brain pathologies such as neuroinfections like acute bacterial meningitis is unclear. Despite focus on aggressive, prompt treatment, morbidity and mortality from acute bacterial meningitis remain high. Increased ICP is well-known to occur in severe neuroinfections. The increased ICP compromise cerebral perfusion pressure and may ultimately lead to brain stem herniation. Therefore, controlling the ICP could also be important in acute bacterial meningitis. However, risk factors for complications due to invasive monitoring among these patients may be significantly increased due to higher age and levels of comorbidity compared to the traumatic brain injury patient from which the ICP treatment algorithms are developed. This narrative review evaluates the different modalities of ICP monitoring with the aim to elucidate current status of non-invasive alternatives to invasive monitoring as a decision tool and eventually monitoring. Non-invasive screening using ultrasound of the optical nerve sheath, transcranial doppler, magnetic resonance imaging or preferably a combination of these modalities, provides measurements that can be used as a decision guidance for invasive ICP measurement. The available data do not support the replacement of invasive techniques for continuous ICP measurement in patients with increased ICP. Non-invasive modalities should be taken into consideration in patients with neuroinfections at low risk of increased ICP.

[Lyme neuroborreliosis in adults]

Lyme neuroborreliosis (LNB) caused by the spirochete bacteria Borrelia burgdorferi sensu lato complex is the most common bacterial neuroinfection in Denmark (180 cases per year). One of the main challenges to LNB is the diagnosis due to its variant manifestations often involving the skin, musculosceletal or nervous system affecting patient morbidity. Recent data shows a diagnostic delay of 21 days in laboratory-confirmed patients in Denmark. The aim of this review is to summarise current state of knowledge concerning clinical manifestations, diagnostic assessment, antibiotic therapy, and prognosis.

The cause of death in bacterial meningitis

Background

Death from bacterial meningitis is rarely attributed to the actual event causing death.

The present study therefore categorized and characterized the cause and time of death due to bacterial meningitis.

Methods

In a cohort of patients > 15 years of age with community acquired bacterial meningitis the medical records were reviewed, and a clinical cause of death categorized into six main categories: 1) CNS complications, 2) Systemic complications, 3) Combination of systemic and CNS complications, 4) Sudden death, 5) Withdrawal of care, or 6) Unknown.

Results

We identified 358 patients of which 84 (23%) died in-hospital. Causes of death were ascribed to CNS complications in 43%, Systemic complications in 39%, Combined CNS and systemic complications in 4%, Sudden death in 7% and withdrawal of care in 5%. Brain herniation, circulatory failure, intractable seizures and other brain injury were the most common specific causes of death within 14 days from admission (55%).

Conclusion

Fatal complications due to the primary infection – meningitis - is most common within 14 days of admission. The diversity of complications causing death in meningitis suggest that determining the clinical cause of death is essential to the evaluation of novel treatment strategies.

Pneumococcal meningitis with normal cerebrospinal biochemistry and no pneumococci at microscopy, mimicking a stroke: a case report

Background

Bacterial meningitis commonly presents with symptoms such as headache, impaired consciousness, neck stiffness, and fever. In most cases, cerebrospinal fluid analysis will yield white cell counts >100/mm³. Atypical presentations occur, especially in the very young or very elderly and the immunocompromised. We report an unusual case of pneumococcal meningitis in a healthy 78-year-old Danish woman who presented with clinical features mimicking a stroke with normal cerebrospinal fluid parameters and without microscopic evidence of bacteria.

Case presentation

The patient was admitted after being found unconscious on her bed. Upon admittance, she was considered confused, with a temperature of 39.4 °C and slight neutrophilic leukocytosis, but no neck stiffness. A neurological examination revealed bilateral horizontal nystagmus, unstable eye movements, and suspected right-sided gaze paralysis. Cerebrospinal fluid analysis revealed normal parameters, and the microscopy result was negative for bacteria. The most likely diagnosis was considered to be stroke with concomitant infection. However, cerebrospinal fluid and blood cultures subsequently were rapidly positive for pneumococci. Neither immunodeficiency nor blood contamination was considered a likely cause of this discrepancy.

Conclusions

This case emphasizes the need to consider a multidisciplinary approach and empirical meningitis treatment until diagnostic results from microbiological cultures are obtained.

Cerebrospinal fluid pleocytosis in infectious and noninfectious central nervous system disease: A retrospective cohort study

Cerebrospinal fluid (CSF) analysis is the most important tool for assessing central nervous system (CNS) disease. An elevated CSF leukocyte count rarely provides the final diagnosis, but is almost always an indicator of inflammation within the CNS.The present study investigated the variety of diseases associated with CSF pleocytosis.CSF analyses were identified through the biochemical database used in the capital region of Denmark in the period from 2003 to 2010. In patients >15 years, clinical diagnoses associated with the finding of a CSF leukocyte count >10 × 10 cells/L were obtained from discharge records and patient files.A total of 1058 CSF samples from 1054 patients were included in the analysis. The median age was 50 (interquartile range: 36-67) and 53% were male. Eighty-one different diagnoses were identified in 1058 cases with an elevated CSF leukocyte count, besides unknown causes. Infections were the most common cause of CSF pleocytosis (61.4%) followed by miscellaneous causes (12.7%), vascular (9.7%), neurodegenerative (7%), neoplastic (5%), and inflammatory conditions (4.2%). Only infections presented with leukocyte counts >10,000 × 10/L. Infections represented 82.6% of all cases with a leukocyte count >100 × 10/L whereas 56.3% of cases with at leukocyte counts <100 × 10/L were dominated by disease not related to infection.The present study may serve as a reminder to clinicians of what diseases and disease categories to suspect when patients present with CSF biochemistry indicating CNS inflammation.

Improved outcome of bacterial meningitis associated with use of corticosteroid treatment

Background The aim of this study was to evaluate the clinical outcome of patients with bacterial meningitis following the introduction of dexamethasone treatment in Denmark. Methods Adult patients with bacterial meningitis, admitted from 2003-2010 to two different university hospitals, were included retrospectively. Data at clinical presentation, Glasgow outcome scale (GOS), cerebrospinal fluid and blood biochemistry were collected. Relative risk (RR) with 95% confidence interval (CI) was computed by Cox proportional hazard regression analysis. Results One hundred and forty-seven patients were included in the study. The population had a median age of 62 years and 31% had an immunosuppressive co-morbidity. Eighty-nine patients had an unfavourable outcome (GOS score = 1-4). Adjuvant treatment with corticosteroids (RR = 0.48; 95% CI = 0.30-0.76) was associated with a favourable outcome (GOS score = 5), while altered mental status (RR = 2.36; 95% CI = 1.17-4.78) and age (RR = 1.03; 95% CI = 1.01-1.04) per year increment was associated with an unfavourable outcome. Adjuvant corticosteroid treatment did not affect short- or long-term survival. Short-term mortality was influenced by age (RR = 1.06; 95% CI = 1.04-1.09). Long-term mortality was influenced by age (RR = 1.06; 95% CI = 1.03-1.08) and female sex (RR = 1.81; 95% CI = 1.05-3.14). Conclusion This study indicated that adjuvant corticosteroid treatment in acute bacterial meningitis improves the outcome and can safely be administered in an elderly population with high levels of immunosuppressive co-morbidity.

Brain ventricular dimensions and relationship to outcome in adult patients with bacterial meningitis

Background

Experimental studies suggest that changes in brain ventricle size are key events in bacterial meningitis. This study investigated the relationship between ventricle size, clinical condition and risk of poor outcome in patients with bacterial meningitis.

Methods

Adult patients diagnosed with bacterial meningitis admitted to two departments of infectious diseases from 2003 through 2010 were identified. Clinical and biochemical data as well as cerebral computed tomographic images were collected. The size of the brain ventricles were presented as a Ventricle to Brain Ratio (VBR). Normal range of VBR was defined from an age matched control group. A multivariate analysis was performed to identify predictors of 30-day mortality.

Results

One hundred and seven patients were included. Eighty-one patients had a CT scan at the time of diagnosis. VBR was identified as an independent risk factor of 30-day mortality, Mortality Rate Ratio: 6.03 (95 % confidence interval: 1.61-22.64, p = 0.008) for highest versus lowest tertile. A VBR deviating more than 2 standard deviations from the normal range was associated with increased mortality.

Conclusions

Brain ventricles are commonly subject to marked changes in size as a consequence of meningitis. Increased brain ventricle size in the acute phase of bacterial meningitis was associated with increased mortality.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-015-1097-3) contains supplementary material, which is available to authorized users.

Macular and peripapillary retinal nerve fibre layer thickness in patients with cyanotic congenital heart disease

PURPOSE

To evaluate macular and retinal nerve fibre layer (RNFL) measurements in patients with cyanotic congenital heart disease (cCHD) using spectral domain optical coherence tomography (OCT).

PATIENTS AND METHODS

Thirty patients with cCHD (18 females and 12 males, mean age 10.9 years) and 60 healthy controls (35 females and 25 males, mean age 11.2 years) underwent complete ophthalmologic examination and OCT measurements of macular and peripapillary RNFL thickness.

RESULTS

Patients with cCHD had significantly thinner measurements in all macular subfields compared with healthy controls (P<0.001). There was no significant difference in peripapillary RNFL thickness between the two groups, with the exception of the upper quadrant, for which thickness measurements were higher in patients with cCHD (P=0.021).

CONCLUSIONS

Patients with cCHD showed a significant decrease in macular thickness and a thickened superior quadrant RNFL thickness when compared with healthy controls. This may represent the damage caused by the effect of hypoxia.

Increase in hippocampal water diffusion and volume during experimental pneumococcal meningitis is aggravated by bacteremia

Background

The hippocampus undergoes apoptosis in experimental pneumococcal meningitis leading to neurofunctional deficits in learning and memory function. The aim of the present study was 1) to investigate hippocampal apparent diffusion coefficient (ADC) and volume with MRI during the course of experimental pneumococcal meningitis, 2) to explore the influence of accompanying bacteremia on hippocampal water distribution and volume, 3) and to correlate these findings to the extent of apoptosis in the hippocampus.

Methods

Experimental meningitis in rats was induced by intracisternal injection of live pneumococci. The study comprised of four experimental groups. I. Uninfected controls (n = 8); II. Meningitis (n = 11); III. Meningitis with early onset bacteremia by additional i.v. injection of live pneumococci (n = 10); IV. Meningitis with attenuated bacteremia by treatment with serotype-specific anti-pneumococcal antibodies (n = 14). T2 and diffusion weighted MR images were used to analyze changes in hippocampus volume and water diffusion (ADC). The results were correlated to ADC of the cortex, to ventricular volume, and to the extent of hippocampal apoptosis.

Results

Both ADC and the volume of hippocampus were significantly increased in meningitis rats compared to uninfected controls (Kruskal-Wallis test, p = 0.0001, Dunns Post Test, p < 0.05), and were significantly increased in meningitis rats with an early onset bacteremia as compared to meningitis rats with attenuated bacteremia (p < 0.05). Hippocampal ADC and the volume and size of brain ventricles were positively correlated (Spearman Rank, p < 0.05), whereas no association was found between ADC or volume and the extent of apoptosis (p > 0.05).

Conclusions

In experimental meningitis increase in volume and water diffusion of the hippocampus are significantly associated with accompanying bacteremia.

Bacteremia causes hippocampal apoptosis in experimental pneumococcal meningitis

Background

Bacteremia and systemic complications both play important roles in brain pathophysiological alterations and the outcome of pneumococcal meningitis. Their individual contributions to the development of brain damage, however, still remain to be defined.

Methods

Using an adult rat pneumococcal meningitis model, the impact of bacteremia accompanying meningitis on the development of hippocampal injury was studied. The study comprised of the three groups: I. Meningitis (n = 11), II. meningitis with attenuated bacteremia resulting from iv injection of serotype-specific pneumococcal antibodies (n = 14), and III. uninfected controls (n = 6).

Results

Pneumococcal meningitis resulted in a significantly higher apoptosis score 0.22 (0.18-0.35) compared to uninfected controls (0.02 (0.00-0.02), Mann Whitney test, P = 0.0003). Also, meningitis with an attenuation of bacteremia by antibody treatment resulted in significantly reduced apoptosis (0.08 (0.02-0.20), P = 0.01) as compared to meningitis.

Conclusions

Our results demonstrate that bacteremia accompanying meningitis plays an important role in the development of hippocampal injury in pneumococcal meningitis.

Experimental studies of pneumococcal meningitis

This thesis summarizes experimental meningitis research conducted at Statens Serum Institut in collaboration with the Copenhagen HIV programme and the Danish Research Centre for Magnetic Resonance between 2001 and 2007. Previous experimental studies had shown that the host inflammatory response in invasive infections contributed significantly to an extremely poor outcome despite initiation of efficient antimicrobial chemotherapy. Consequently, we aimed to investigate and clarify how the course of disease in pneumococcal meningitis was modulated by local meningeal inflammation and concomitant systemic infection and inflammation. Experimental studies were based on the development of a rat model of pneumococcal meningitis, refined and optimized to closely resemble the human disease, mimicking disease severity, outcome, focal- and global brain injury and brain pathophysiology. These endpoints were evaluated by the development of a clinical score system, definition of outcomes and measurement of hearing loss by otoacoustic emission. The investigation of in-vitro and in-vivo brain pathology with histology and MRI revealed an injury pattern similar to that found clinically. Additionally, MRI enabled the study of parameters closely related to the cerebral pathophysiology of meningitis (brain oedema, blood brain barrier (BBB) permeability, focal brain injury and hydrocephalus). Modulation of the inflammatory host response was achieved by initiation of treatment prior to infection: 1) G-CSF treatment increased the peripheral availability of leukocytes, 2) Selectin blocker fucoidin attenuated meningeal leukocyte accumulation and 3) A serotype specific Ab augmented systemic pneumococcal phagocytosis. The studies revealed a dual role of the inflammatory response in pneumococcal meningitis. Whilst focal brain injury appeared to result from local meningeal infectious processes, clinical disease severity and outcome appeared determined by systemic infection. Furthermore systemic disease contributed significantly to BBB permeability and brain ventricle expansion. Ventricle expansion was also associated with clinical appearance. An augmented systemic host response limited pneumococcal bacteraemia and protected from fatal outcome, but did not reduce occurrence of focal brain injury. Thus, our findings suggest that meningitis sequelae arise from local disease complications whereas fatal outcome is accelerated by systemic infection. Understanding of the relationship and interplay between septicaemia, intracranial pressure, ventricle expansion and brain edema could help optimize the treatment of these disease complications by, for example, improved systemic infection control. New therapeutic approaches to improve survival and neurological outcome from pneumococcal meningitis may be achieved through identification of the pathogen factors that initiate and prolong extensive systemic and local inflammation. Investigation of genomic differences and protein expression between pneumococcal serotypes or between identical serotypes with different virulence are considered crucial to this progress. Future progress may also be achieved by disease prevention with pneumococcal vaccines. Randomized trials of treatment strategies including bacteriostatic agents, antioxidants or more specific anti-inflammatory agents are realistic possibilities in the near future.

Danish integrated antimicrobial resistance monitoring and research program

Resistance to antimicrobial agents is an emerging problem worldwide. Awareness of the undesirable consequences of its widespread occurrence has led to the initiation of antimicrobial agent resistance monitoring programs in several countries. In 1995, Denmark was the first country to establish a systematic and continuous monitoring program of antimicrobial drug consumption and antimicrobial agent resistance in animals, food, and humans, the Danish Integrated Antimicrobial Resistance Monitoring and Research Program (DANMAP). Monitoring of antimicrobial drug resistance and a range of research activities related to DANMAP have contributed to restrictions or bans of use of several antimicrobial agents in food animals in Denmark and other European Union countries.

In vivo study of experimental pneumococcal meningitis using magnetic resonance imaging

BACKGROUND

Magnetic Resonance Imaging (MRI) methods were evaluated as a tool for the study of experimental meningitis. The identification and characterisation of pathophysiological parameters that vary during the course of the disease could be used as markers for future studies of new treatment strategies.

METHODS

Rats infected intracisternally with S. pneumoniae (n = 29) or saline (n = 13) were randomized for imaging at 6, 12, 24, 30, 36, 42 or 48 hours after infection. T1W, T2W, quantitative diffusion, and post contrast T1W images were acquired at 4.7 T. Dynamic MRI (dMRI) was used to evaluate blood-brain-barrier (BBB) permeability and to obtain a measure of cerebral and muscle perfusion. Clinical- and motor scores, bacterial counts in CSF and blood, and WBC counts in CSF were measured.

RESULTS

MR images and dMRI revealed the development of a highly significant increase in BBB permeability (P < 0.002) and ventricle size (P < 0.0001) among infected rats. Clinical disease severity was closely related to ventricle expansion (P = 0.024). Changes in brain water distribution, assessed by ADC, and categorization of brain 'perfusion' by cortex DeltaSI(bolus) were subject to increased inter-rat variation as the disease progressed, but without overall differences compared to uninfected rats (P > 0.05). Areas of well-'perfused' muscle decreased with the progression of infection indicative of septicaemia (P = 0.05).

CONCLUSION

The evolution of bacterial meningitis was successfully followed in-vivo with MRI. Increasing BBB-breakdown and ventricle size was observed in rats with meningitis whereas changes in brain water distribution were heterogeneous. MRI will be a valuable technique for future studies aiming at evaluating or optimizing adjunctive treatments.

The effect of S. pneumoniae bacteremia on cerebral blood flow autoregulation in rats

In the present study, we studied the effect of bacteremia on cerebral blood flow (CBF) autoregulation in a rat model of pneumococcal bacteremia and meningitis. Anesthetized rats were divided into five groups (A to E) and inoculated with pneumococci intravenously and normal saline intracisternally (group A, N=10); saline intravenously and pneumococci intracisternally (group B, N=10); pneumococci intravenously and pneumococci intracisternally (group C, N=5); saline intravenously, antipneumococcal antibody intravenously (to prevent bacteremia), and pneumococci intracisternally (group D, N=10); or saline intravenously and saline intracisternally (group E, N=10), respectively. Positive cultures occurred in the blood for all rats in groups A, B, and C, and in the cerebrospinal fluid for all rats in groups D and E. Twenty-four hours after inoculation, CBF was measured with laser-Doppler ultrasound during incremental reductions in cerebral perfusion pressure (CPP) by controlled hemorrhage. Autoregulation was preserved in all rats without meningitis (groups A and E) and was lost in 24 of 25 meningitis rats (groups B, C, and D) (P<0.01). In group A, the lower limit was higher than that of group E (P<0.05). The slope of the CBF/CPP regression line differed between the meningitis groups (P<0.001), being steeper for group B than groups C and D, with no difference between these two groups. The results suggest that pneumococcal bacteremia in rats triggers cerebral vasodilation, which right shifts the lower limit of, but does not entirely abolish, CBF autoregulation in the absence of meningitis, and which may further aggravate the vasoparalysis induced by concomitant pneumococcal meningitis.

Global development of resistance--secondary publication

Antibiotic resistance is an increasing problem world wide, although in some areas the increase in resistance is slow, as in the Nordic countries. Multiresistant staphylococci, Enterobacteriaceae and Mycobacterium tuberculosis are already causing increased morbidity, mortality and huge costs in health budgets. New effective antibiotics will not be available for the next 10-15 years, since the pharmaceutical industry has lost interest in antibiotics. The major determinant in this field, in order to save the activity of the known antibiotics, is the control of antibiotic use.

A comparison of antibiotic use in children between Canada and Denmark

BACKGROUND

High rates of antibiotic prescribing in children lead to antibiotic resistance in the community. Surveillance on utilization rates and comparisons with other jurisdictions are methods for benchmarking. Surveillance on antibiotic use is well established in Europe, including Denmark, but until recently, similar data from Canada were lacking.

OBJECTIVE

To compare pediatric antibiotic prescribing rates in British Columbia, Canada, with those in Denmark.

METHODS

Population-based data on antibiotic prescriptions from British Columbia and Denmark were obtained from 1999 to 2003 for children less than 15 years of age. Annual trends in prescription rates per 1000 children were analyzed by using generalized linear models for all children less than 15 years of age; they were stratified by age group (0-4, 5-9, 10-14 y) for all antibiotics. Class-specific trends were also evaluated for penicillins, cephalosporins, macrolides, sulfonamides and trimethoprim, tetracyclines, and fluoroquinolones.

RESULTS

From 1999 to 2003, the overall British Columbia prescription rate was significantly higher than that of Denmark (p < 0.0001) at all age stratifications. In 2003, the British Columbia prescription rate was twice that of Denmark, at 608 versus 385 prescriptions per 1000 children, respectively. In both jurisdictions, the majority of antibiotics used were penicillins (Anatomical Therapeutic Chemical class J01C). However, in British Columbia, most penicillins used were extended-spectrum (83% in 2003); in Denmark, 34% of penicillins used in 2003 were extended-spectrum and 56% were beta-lactamase sensitive. In British Columbia, use of penicillins (-4.5%), cephalosporins (-5.5%), trimethoprim/sulfamethoxazole (-36%), and tetracycline (-1.6%) decreased over time, whereas in Denmark, use of penicillins increased by 11% over time and non-penicillin antibiotics remained stable. A significant increase in macrolide consumption was seen in British Columbia due to use of clarithromycin and azithromycin; in contrast, macrolide consumption declined in Denmark.

CONCLUSIONS

Compared with Denmark, the antibiotic prescription rate for children is substantially higher in British Columbia. In addition, there has been a significant increase in the use of macrolides, especially the second-generation agents, in British Columbia compared with the use in Denmark. Further studies are required to delineate reasons for antibiotic prescribing patterns in these 2 jurisdictions.

Cerebral blood flow autoregulation in early experimental S. pneumoniae meningitis

We studied cerebral blood flow (CBF) autoregulation and intracranial pressure (ICP) during normo- and hyperventilation in a rat model of Streptococcus pneumoniae meningitis. Meningitis was induced by intracisternal injection of S. pneumoniae. Mean arterial blood pressure (MAP), ICP, cerebral perfusion pressure (CPP, defined as MAP − ICP), and laser-Doppler CBF were measured in anesthetized infected rats ( n = 30) and saline-inoculated controls ( n = 30). CPP was either incrementally reduced by controlled hemorrhage or increased by intravenous norepinephrine infusion. Twelve hours postinoculation, rats were studied solely during normocapnia, whereas rats studied after 24 h were exposed to either normocapnia or to acute hypocapnia. In infected rats compared with control rats, ICP was unchanged at 12 h but increased at 24 h postinoculation (not significant and P < 0.01, respectively); hypocapnia did not lower ICP compared with normocapnia. Twelve hours postinoculation, CBF autoregulation was lost in all infected rats but preserved in all control rats ( P < 0.01). Twenty-four hours after inoculation, 10% of infected rats had preserved CBF autoregulation during normocapnia compared with 80% of control rats ( P < 0.01). In contrast, 60% of the infected rats and 100% of the control rats showed an intact CBF autoregulation during hypocapnia ( P < 0.05 for the comparison of infected rats at normocapnia vs. hypocapnia). In conclusion, CBF autoregulation is lost both at 12 and at 24 h after intracisternal inoculation of S. pneumoniae in rats. Impairment of CBF autoregulation precedes the increase in ICP, and acute hypocapnia may restore autoregulation without changing the ICP.

Evaluation of anti-pneumococcal capsular antibodies as adjunctive therapy in experimental pneumococcal meningitis

OBJECTIVE

Bacteraemia concomitant with meningitis has been shown to greatly affect outcome. Consequently, the efficacy of serotype-specific anti-pneumococcal antiserum (APAS) was investigated in a rat model of pneumococcal meningitis.

METHODS

Rats were infected with Streptococcus pneumoniae serotype 3. All rats received ceftriaxone starting 26 h post-infection. APAS was administered either at the time of infection or 26 h post-infection and effects were compared with rats treated with antibiotics only.

RESULTS AND CONCLUSION

A significant clinical benefit was found when APAS was given at the time of infection whereas no effect was found when administered 26 h after infection. This work indicates that the clinical value of using APAS in pneumococcal meningitis may be limited.

[Trends in global antibiotic resistance]

Antibiotic resistance is an increasing problem world wide, although in some areas the increase in resistance is slow, as in the Nordic countries. Multiresistant staphylococci, Enterobaceriaceae and Mycobacterium tuberculosis are already causing increased morbidity, mortality and huge costs in health budgets. New effective antibiotics will not be available for the next 10-15 years, since the pharmaceutical industry has lost interest in antibiotics. The major determinant in this field, in order to save the activity of the known antibiotics, is the control of antibiotic use.

Hearing loss and cochlear damage in experimental pneumococcal meningitis, with special reference to the role of neutrophil granulocytes

Hearing loss is a well-known sequelae from meningitis, affecting up to 25% of survivors. However, the principal components of the infectious and inflammatory reaction responsible for the sensorineural hearing loss remain to be identified. The present study aimed to investigate the impact of an augmented neutrophil response on the development of hearing loss and cochlear damage in a model of experimental pneumococcal meningitis in rats. Hearing loss and cochlear damage were assessed by distortion product oto-acoustic emissions (DPOAE), auditory brainstem response (ABR) and histopathology in rats treated with ceftriaxone 28 h after infection. Rats were treated with Granulocyte Colony Stimulating Factor (G-CSF) initiated prior to infection, 28 h after infection or with ceftriaxone only. Rats were followed for 7 days, and assessment of hearing was performed before infection and 24 h and day 8 after infection. Pretreatment with G-CSF increased hearing loss 24 h after infection and on day 8 compared to untreated rats (Mann-Whitney, P = 0.012 and P = 0.013 respectively). The increased sensorineural hearing loss at day 8 was associated with significantly decreased spiral ganglion cell counts (P = 0.0006), increased damage to the organ of Corti (P = 0.007), increased areas of inflammatory infiltrates (P = 0.02) and increased white blood cell (WBC) counts in cerebrospinal fluid on day 8 after infection (P = 0.0084). Initiation of G-CSF 28 h after infection did not significantly affect hearing loss or cochlear pathology compared to controls. In conclusion, the inflammatory host reaction contributes significantly to the development of hearing loss in experimental meningitis.

Blocking of leukocyte accumulation in the cerebrospinal fluid augments bacteremia and increases lethality in experimental pneumococcal meningitis

The role of leukocyte accumulation in the cerebrospinal fluid (CSF) in the evolution of the pathophysiological changes that occur in bacterial meningitis is unclear. Here, we investigate how leukocyte recruitment to the CSF, modulated by the leukocyte blocker fucoidin, affects the extent of brain damage and outcome in pneumococcal meningitis in rats treated with ceftriaxone from 28 h after infection. Rats treated with fucoidin from time of infection had an excess risk of a fatal outcome compared to rats not receiving fucoidin (25/63 versus 5/34, p=0.012), whereas the risk of cortical damage in surviving animals was comparable (16/44 versus 9/29, p=0.8). Pre-treatment with fucoidin attenuated CSF pleocytosis 24 h after infection (median 400 versus 800x10(6) cells/l, p=0.01) without affecting CSF bacterial counts (2.3x10(5) versus 3.6x10(5) CFU/ml, p=0.54). A significant increase in blood bacterial counts was found among rats pre-treated with fucoidin (median 9.6x10(2) versus 5.2x10(2) CFU/ml, p=0.03). Furthermore, blood bacterial count was found to be an important predictor of fatal outcome as shown by multivariate logistical regression analysis (OR 4.43, 95% CI [1.16-17.0] p=0.03). In summary, blocking leukocyte entry to the central nervous system in experimental pneumococcal meningitis compromises the survival prognosis but does not affect the risk of brain damage or level of infection in this compartment. Conversely, poorer prognosis was associated with an increase in bacterial load in blood, suggesting that leukocyte blockage affects the host's ability to control systemic infection.

Increase and change in pattern of hospital antimicrobial use, Denmark, 1997–2001

OBJECTIVES

To analyse the changes and compare antimicrobial consumption in public hospitals in Denmark over the period 1997-2001.

METHODS

Data on the number of WHO defined daily doses (DDD) were obtained from the Danish Medicines Agency. Data on the number of bed-days were obtained from the National Board of Health. We calculated antimicrobial consumption in hospitals as the number of DDD per 100 bed-days for all antibacterials for systemic use i.e. group J01 of the Anatomical Therapeutic Chemical (ATC) classification and for classes of this group.

RESULTS

During 1997-2001, antimicrobial use in hospitals in Denmark significantly increased by 18%, from 38.0 to 44.8 DDD per 100 bed-days (P < 0.005). Most of this increase (55%) was attributed to an increase in consumption of commonly used classes of antimicrobials, mainly penicillins with extended spectrum (ATC group J01CA), beta-lactamase-sensitive penicillins (J01CE) and beta-lactamase-resistant penicillins (J01CF). The 'broad-spectrum' and newer antimicrobials, i.e. combinations of penicillins with beta-lactamase inhibitor (J01CR), cephalosporins (J01DA), carbapenems (J01DH) and fluoroquinolones (J01MA) contributed to 36% of the increase. Together, these amounted to 16% of total consumption in hospitals in Denmark in 1997, rising to 19% in 2001.

CONCLUSIONS

Although antimicrobial consumption in public hospitals in Denmark is low compared with other countries, the steady increase and change in pattern of their use are causes of concern, deserving close monitoring and further investigations.

Attenuation of the bacterial load in blood by pretreatment with granulocyte-colony-stimulating factor protects rats from fatal outcome and brain damage during Streptococcus pneumoniae meningitis

A model of pneumococcal meningitis in young adult rats receiving antibiotics once the infection was established was developed. The intent was to mimic clinical and histopathological features of pneumococcal meningitis in humans. The primary aim of the present study was to evaluate whether medical boosting of the peripheral neutrophil count affected the outcome of the meningitis. The risk of terminal illness over the first 7 days after infection was significantly reduced for rats who had elevated peripheral white blood cell counts after receiving granulocyte-colony-stimulating factor (G-CSF) prior to the infection compared to that for untreated rats (P = 0.039 by the log rank test). The improved outcome was associated with reduced signs of cerebral cortical damage (P = 0.008). Furthermore, the beneficial effects of G-CSF were associated with reduced bacterial loads in the cerebrospinal fluid (median, 1.1 x 10(5) versus 2.9 x 10(5) CFU/ml; P = 0.023) and in blood (median, 2.9 x 10(2) versus 6.3 x 10(2) CFU/ml; P = 0.024), as well as attenuated pleocytosis (median, 800 x 10(6) versus 1,231 x 10(6) cells/liter; P = 0.025), 24 h after the infection. Conversely, initiation of G-CSF therapy 28 h postinfection did not alter the clinical or histological outcome relative to that for non-G-CSF-treated rats. The magnitude of bacteremia and pretreatment with G-CSF were found to be prognostic factors for both outcome and brain damage. In summary, elevated neutrophil levels prior to the development of meningitis result in reduced risks of death and brain damage. This beneficial effect is most likely achieved through improved control of the systemic disease.

Elevated levels of erythrocyte-conjugated dienes indicate increased lipid peroxidation in schistosomiasis mansoni patients

Schistosoma mansoni causes liver disease by inducing granulomatous inflammation. This favors formation of reactive oxygen species, including superoxide ions, hydrogen peroxide and hydroxyl radicals all of which may induce lipid peroxidation. We have evaluated lipid peroxidation in 18 patients with hepatosplenic schistosomiasis mansoni previously treated with oxamniquine followed by splenectomy, ligature of the left gastric vein and auto-implantation of spleen tissue, by measuring levels of erythrocyte-conjugated dienes and plasma malondialdehyde (MDA). Age-matched, healthy individuals (N = 18) formed the control group. Erythrocyte-conjugated dienes were extracted with dichloromethane/methanol and quantified by UV spectrophotometry, while plasma MDA was measured by reaction with thiobarbituric acid. Patient erythrocytes contained two times more conjugated dienes than control cells (584.5 +/- 67.8 vs 271.7 +/- 20.1 micromol/l, P < 0.001), whereas the increase in plasma MDA concentration (about 10%) was not statistically significant. These elevated conjugated dienes in patients infected by S. mansoni suggest increased lipid peroxidation in cell membranes, although this was not evident when a common marker of oxidative stress, plasma MDA, was measured. Nevertheless, these two markers of lipid peroxidation, circulating MDA and erythrocyte-conjugated dienes, correlated significantly in both patient (r = 0.62; P < 0.01) and control (r = 0.57; P < 0.05) groups. Our data show that patients with schistosomiasis have abnormal lipid peroxidation, with elevated erythrocyte-conjugated dienes implying dysfunctional cell membranes, and also imply that this may be attenuated by the redox capacity of antioxidant agents, which prevent accumulation of plasma MDA.

Autotransplant of spleen tissue in children with schistosomiasis: evaluation of splenic function after splenosis

Autotransplantation of spleen tissue has been done, in the past ten years, in children with schistosomiasis mansoni with bleeding varices. The purposes of this investigation were: (1) to study the morphology and function of the remnant spleen tissue; (2) to quantify the production of tuftsin; and (3) to assess the immune response to pneumococcal vaccine of these patients. Twenty three children, who underwent splenectomy and autologous implantation of spleen tissue into the greater omentum were included in this investigation. The average postoperative follow-up is five years. Splenosis was proved by colloid liver-spleen scans. Search for Howell-Jolly bodies assessed the filtration function. Tuftsin and the titer of pneumococcal antibodies were quantified by ELISA. Splenosis was evident in all children; however, it was insufficient in two. Howell-Jolly bodies were found only in these two patients. The mean tuftsin serum concentration (335.0 +/- 29.8 ng/ml) was inside the normal range. The immune response to pneumococcal vaccination was adequate in 15 patients; intermediate in four; and inadequate in four. From the results the following conclusions can be drawn: splenosis was efficient in maintaining the filtration splenic function in more than 90% and produced tuftsin inside the range of normality. It also provided the immunologic splenic response to pneumococcal vaccination in 65% of the patients of this series.

Surgical hepatosplenic mansonic schistosomiasis in adolescents: repercussions of the post-treatment schistosomotic burden on the hepatic functional reserve

Schistosomiasis mansoni affects the hepatic functional reserve. Clinical treatment with oxamniquine is not 100% effective and there has been found strain of this parasite resistant to this drug. The aims of this investigation were: (1) to examine the presence of residual parasite burden after medical and surgical treatment on adolescents with surgical schistosomiasis mansoni and (2) to assess the effect on the hepatic functional reserve in patients with and without residual infection. Twenty nine children with hepatosplenic schistosomiasis mansoni and bleeding esophageal varices were treated with oxamniquine. They underwent splenectomy, ligature of the left gastric vein and autologous implantation of spleen tissue into the greater omentum. After a mean post-operative follow up of five years they underwent rectal biopsy for schistosomotic egg search. They were divided in patients with and without infection. In 20 patients the submucosal egg search was negative, however, in 9 it was positive. The hepatic functional reserve in the patients without infection was as follows: 17 were Child-Pugh A and 3 Child-Pugh B. In the patients who were still infected 6 were Child-Pugh A and 3 Child-Pugh B. The chi2 analysis of the hepatic functional reserve showed chi2 = 3.19 - p= 0.07. From the results the following conclusion can be drawn: residual infection or reinfection in the follow up period had not interfered with the distribution of the hepatic functional reserve of the patients in this series. However, there was a trend for a decrease of this parameter in patients with residual infection.

[Phlebitis due to venous catheters. Causes and occurrence]

Seventy-nine patients admitted to Frederiksberg Hospital had peripheral intravenous catheters inserted to aid treatment. We followed the patients in order to determine the frequency of phlebitis, and to isolate mechanical and chemical parameters that increase the risk of phlebitis. The frequency of phlebitis was 27.8%. We found that 35.8% of all complications evolve when the catheter has been inserted for more than 72 hours, and that 45.5% of patients treated with antibiotics develop phlebitis. Furthermore, it seems that acetyl salicylic acid reduces the number of cases with phlebitis. Catheters inserted around the wrist have a higher frequency of phlebitis. Changing the catheters every 72 hours significantly reduces the frequency of phlebitis by 40%. The risk of developing a septic condition due to catheter-induced phlebitis seems small because we suggest that phlebitis is an inflammatory reaction to the plastic-catheter, and not infectious.

Densities of nitric oxide synthesizing nerves in smooth muscles of human gut during fetal development

BACKGROUND/PURPOSE

Nitric oxide (NO) plays a role in inhibitory neurotransmission in the sphincteric and nonsphincteric smooth muscles. However, the relative contribution of NO synthesizing innervation to these functionally diverse parts of the gut, particularly during development, is unknown.

METHODS

Gastrointestinal sphincters and adjoining nonsphincteric bowel segments were obtained from 14 human fetuses (gestation, 12 to 23 weeks). NO synthesizing nerves were examined by nicotinamide adenine deoxinucleotide phosphate (NADPH) diaphorase histochemistry. The densities of NADPH-positive nerves in the smooth muscles were quantified using a computerized image analyzing system on random sections.

RESULTS

The NO synthesizing nerve density in intestinal smooth muscles decreased during fetal development as a result of increased interspacing between myenteric ganglia and a disproportionately larger increase in smooth muscle area than neuronal area. The nerve densities were lower in sphincteric regions than the adjoining nonsphincteric regions at the same gestation.

CONCLUSION

These findings may have relevance to the occurrence of congenital dysmotility disorders of the sphincteric regions.

Anti-interleukin-8 monoclonal antibody reduces free radical production and improves hemodynamics and survival rate in endotoxic shock in rabbits

BACKGROUND

Although high levels of interleukin-8 (IL-8) have been found in patients with sepsis and a monoclonal antibody (MoAb) against IL-8 has been successfully used in some animal models of inflammation, no specific therapeutic agent against IL-8 has been tested for the treatment of sepsis. We studied the effects of a MoAb against IL-8 in the treatment of endotoxic shock with a prospective randomized rabbit endotoxic shock model.

METHODS

Twenty New Zealand white rabbits were anesthetized and divided into four groups: normal, anti-IL-8, control-Ab, and lipopolysaccharide (LPS). Anti-IL-8 and control-Ab groups received a MoAb (immunoglobulin G, 3 mg/kg) 5 minutes before the LPS injection. All groups, except the normal group, received a continuous 20-minute infusion of LPS (500 micrograms/kg). The normal group received NaCl (0.9%) rather than LPS.

RESULTS

The 7-day survival rates were 100% for normal group, 80% for anti-IL-8 group, 40% for control-Ab group, and 0% for LPS group. Compared with the LPS group, anti-IL-8 rabbits had a smaller decrease in mean arterial blood pressure (p < 0.05) and increased urinary volume (p < 0.05). Anti-IL-8 rabbits had lower plasmatic levels of IL-1 beta, less free radical production (p < 0.05), and a higher survival rate (p < 0.01).

CONCLUSIONS

IL-8 plays a significant role in endotoxic shock, and IL-8 blockage results in attenuation of the hypotensive and tachypneic effects of LPS, reduced free radical production, and an increased survival rate after lethal endotoxic shock.

Nitrergic innervation of the human gut during early fetal development

Classically, development of the human enteric nervous system has been characterized by the early appearance (between 9 and 12 weeks' gestation) of adrenergic and cholinergic nerves. The development of peptidergic innervation occurs much later. Recent studies have indicated that nitric oxide is involved in the nonadrenergic noncholinergic innervation of the gut, mediating its relaxation. The authors have investigated the ontogeny of nitrergic (nitric oxide synthase-containing) neurons of the developing gut. Bowel segments from the esophagus, pylorus, and ileocecal and rectosigmoid regions of 14 fetuses (gestational age range, 12 to 23 weeks) were studied with nicotinamide adenosine dinucleotide phosphate (NADPH) diaphorase histochemistry. By 12 weeks' gestation, nitrergic neurons had appeared in the myenteric ganglia, at all levels of the gut, and had begun plexus formation. Nitrergic innervation in the submucous plexus becomes evident after 14 weeks. As gestational age increases, nitrergic innervation becomes richer and more organized. Increasing numbers of nitrergic nerve fibers are seen in the circular muscle; some of these fibers project from the myenteric plexus. By 23 weeks' gestation, nitrergic innervation has matured to the pattern observed in the postnatal gut. Thus, the onset and pace of development of nitrergic innervation are similar to adrenergic and cholinergic innervation and occur before peptidergic innervation. This study provides morphological evidence of the ontogenetic significance of nitrergic innervation in the human gut and supports previous suggestions that nitric oxide has a pathophysiological role in developmental gut motility disorders.

Surgical hepatosplenic schistosomiasis mansoni in children: a Doppler duplex study of the portal vein and the hepatic artery

From January 1990 to September 1993, 25 children with hepatosplenic schistosomiasis mansoni and oesophageal varices underwent splenectomy, ligature of the left gastric vein and autoimplantation of 100 g of spleen into the great omentum at the University Hospital, Recife, Brazil. The diameters and the blood flow velocities of the portal vein and the hepatic artery were measured before and after surgery. A Doppler Duplex (Aloka 680) with a convex transductor of 3.5 MHz was used. Post-operative follow-up revealed (i) a significant decrease in the mean diameter of the portal vein from 12.6 +/- 2.1 mm to 9.6 +/- 1.9 mm, (ii) a significant increase in the mean diameter of the hepatic artery from 5.0 +/- 1.4 mm to 5.3 +/- 1.2 mm, (iii) a significant decrease in the mean blood flow velocity in the portal vein from 31.1 +/- 8.0 cm/s to 22.4 +/- 7.1 cm/s, and (iv) no significant change in blood flow velocity in the hepatic artery. The study supports the concept that surgical treatment for portal hypertension in patients with hepatosplenic schistosomiasis mansoni, which includes splenectomy, results in a decrease of venous portal blood flow to the liver associated with an increase in the arterial hepatic blood flow. The physiological implications of these haemodynamic changes in the long term remain to be investigated.

Splenic embolization in children: long-term efficacy

Eighteen partial splenic embolization procedures (PSEs) were performed in 17 children for hypersplenism (13) and/or esophageal variceal hemorrhage (12). The underlying disease was biliary atresia (BA) in nine children, portal vein thrombosis (PVT) in four, and biliary cirrhosis (BC) in four. From 20% to 90% of the spleen was embolized. Immediate morbidity was high, albeit minor, and the initial hospitalization was protracted for an average of 16 days. The children were followed from 4 to 81 months (average, 34.2). Four patients with BA patients subsequently had liver transplantation at an average of 20 months after PSE. In ten of 13 patients with hypersplenism, hematologic indexes returned to and remained normal throughout follow-up. The three exceptional patients (who had only 20%, 60% and 60% splenic embolization) developed recurrent mild hypersplenism, one of whom was reembolized and is free from hypersplenism 22 months later. Variceal hemorrhage was ameliorated in all 12 patients (average, 2.4 episodes of hemorrhage per year before PSE, 0.5 per year afterwards). Overwhelming postsplenectomy sepsis did not occur in an aggregate follow-up of 48.5 years. PSE is a legitimate treatment alternative for hypersplenism and for esophageal varices in children.