Neurologic complications of metronidazole. Can J Neurol Sci. 2013;40:768-776. [PMID: 24257215 DOI: 10.1017/s0317167100015870]

Antimicrobial peptide DP7 alleviates dextran sulfate sodium (DSS)-induced colitis via modifying gut microbiota and regulating intestinal barrier function

Inflammatory bowel diseases (IBDs), such as Crohn's disease (CD) and ulcerative colitis (UC), represent a growing global health concern. Restoring the balance of the gut microbiota, a crucial factor in intestinal health, offers potential for treating IBD. DP7, a novel antimicrobial peptide with potent antibacterial activity, was investigated for its anti-inflammatory effects in a dextran sulfate sodium (DSS)-induced UC mouse model. DP7 significantly ameliorated key disease parameters, including disease activity index, weight loss, and shortened colon length, while preserving colonic epithelial integrity and reducing inflammatory infiltration. Further analysis revealed potential targets of DP7, highlighting the significant role of Muribaculaceae bacteria during inflammatory states. To further explore the role of the gut microbiota in DP7's efficacy, fecal microbiota transplantation (FMT) was performed using feces from DP7-treated mice. FMT successfully ameliorated colitis in recipient mice, providing further evidence for the crucial role of the gut microbiome in IBD treatment and DP7's ability to modulate the gut microbiota for therapeutic benefit. Moreover, our findings suggest that DP7's modulation of the immune system is intricately linked to the complex microbial environment. Our findings demonstrate that DP7 effectively mitigates inflammation, attenuates barrier dysfunction, and shapes the gut microbiota, suggesting its potential as a therapeutic agent for UC.

Unveiling the Neurotoxicity of Metronidazole: A Clinical Conundrum

Metronidazole, a commonly used antiprotozoal agent, has been linked to neurotoxicity in a few individuals. We present the case of a 61-year-old gentleman diagnosed with a liver abscess, who received a total dose of 64 g of metronidazole over a four-week duration. He subsequently developed slurred speech, numbness, and tingling sensation in both feet. His neuroimaging revealed T2 hyperintensities in the bilateral dentate nuclei and withdrawal of the drug led to symptomatic improvement in the patient. Metronidazole is known to produce neurological manifestations with involvement of peripheral nerves and cerebellum commonly. In the present case, the cumulative dose impact of metronidazole on the dentate nucleus was evident.

Frequency and Risk Factor Analysis for Metronidazole-Associated Neurologic Adverse Events

BACKGROUND

Little is known about the risk factors and frequency of metronidazole-associated neurological adverse events.

OBJECTIVE

To investigate the risk factors and frequency of metronidazole-associated neurological adverse events.

DESIGN

This retrospective study contained two parts. First, we investigated metronidazole treatment-associated neurologic adverse events by performing a population-based cohort study using the Korea Adverse Event Reporting System (KAERS) database from January 2011 to December 2020. Second, we conducted a matched case-control study based on a retrospective cohort of patients treated with metronidazole between January 2006 and July 2021 at a tertiary hospital in South Korea. The data analysis was performed from August 2021 to April 2022.

PARTICIPANTS

In the case-control study, case patients were defined as those diagnosed with metronidazole-associated encephalopathy or peripheral neuropathy during the study period with causal assessment based on the clinical diagnoses and findings from associated tests. In a ratio of 1:3, case patients were compared to a control group of patients prescribed metronidazole without neurologic adverse events matched for age and cumulative dose of metronidazole.

MAIN MEASURES

Frequency and risk factors for metronidazole-associated neurological adverse events.

KEY RESULTS

Overall, 2,309 cases of neurologic adverse events were reported to the KAERS from 2011 to 2020, and the number of reported neurological adverse events showed an increasing trend. Further, 92,838 patients were prescribed metronidazole during the study period at the Severance Hospital; 54 patients were diagnosed with metronidazole-associated encephalopathy or peripheral neuropathy, 40 with central and 28 with peripheral nervous system adverse events. Liver cirrhosis, chronic kidney disease, intravenous administration, and lower body weight were identified as risk factors for these adverse events.

CONCLUSIONS

The number of reported metronidazole-associated neurological adverse events are increasing. Prolonged metronidazole treatment in patients with the aforementioned factors requires careful examination for neurological adverse events.

Gastrointestinal manifestations seen in pediatric patients diagnosed with small fiber neuropathy

OBJECTIVES

Small fiber neuropathy (SFN) affects the fibers involved in cutaneous and visceral pain and temperature sensation and are a crucial part of the autonomic nervous system. Autonomic dysfunction secondary to SFN and autoimmune receptor antibodies is being increasingly recognized, and gastrointestinal (GI) manifestations include constipation, early satiety, nausea, vomiting, and diarrhea. Enteric nervous system involvement may be a possible explanation of abnormal GI motility patterns seen in these patients.

METHODS

Children suspected to have SFN based on symptoms underwent skin biopsy at the Child Neurology clinic at Arnold Palmer Hospital for Children, which was processed at Therapath™ Neuropathology. SFN was diagnosed using epidermal nerve fiber density values that were below 5th percentile from the left distal leg (calf) as reported per Therapath™ laboratory.

RESULTS

Twenty-six patients were diagnosed with SFN. Retrospective chart review was performed, including demographic data, clinical characteristics, and evaluation. A majority of patients were white adolescent females. Autonomic dysfunction, including orthostasis and temperature dysregulation were seen in 61.5% of patients (p = 0.124). Somatosensory symptoms, including pain or numbness were seen in 85% of patients (p < 0.001). GI symptoms were present in 85% of patients (p < 0.001) with constipation being the most common symptom seen in 50% of patients. This correlated with the motility testing results.

CONCLUSIONS

Pediatric patients with SFN commonly have GI symptoms, which may be the main presenting symptom. It is important to recognize and look for symptoms of small fiber neuropathy in children with refractory GI symptoms that may explain multisystemic complaints often seen in these patients.

Metronidazole-Induced Acute Cerebellitis in a Young Patient: Unusual Onset, Delayed Remission, and Characteristic Imaging Features

Metronidazole-induced acute cerebellitis is an exceptionally rare condition resulting from severe adverse reactions to metronidazole, a medication generally employed in the management of infections caused by anaerobic microbes. Although neuropathy has been linked to metronidazole use, reports of acute cerebellitis are infrequent. The neurological effects associated with metronidazole can include weakness, dysarthria, postural instability, seizures, giddiness, vertigo, ataxia, confusion, encephalopathy, headaches, and tremors. The onset of cerebellitis can vary, occurring as early as one day or after several weeks of metronidazole treatment. This article presents a case of a young girl who presented to us with weakness in both upper and lower limbs, dysarthria, and postural instability after exposure to 12 grams of metronidazole (suicidal, 30 tablets of 400 mg). With the above-mentioned complaints, the patient was advised of magnetic resonance imaging of the brain, which showed the features of cerebellitis.

More than just a number: the gut microbiota and brain function across the extremes of life

Understanding the interrelationship between the gut microbiota and host physiology, although still in its relative infancy, has taken important steps forward over the past decade. In the context of brain disorders including those characterized by neurodevelopmental and neurodegenerative changes there have been important advances. However, initially research involved correlational analyses, had limited translational scope, and lacked functional assessments. Thus, largescale longitudinal clinical investigations that assess causation and underlying mechanisms via in depth analysis methods are needed. In neurodegeneration research, strong causal evidence now links the gut microbiome to Alzheimer's (AD), and Parkinson's Disease (PD), as supported by human-to-animal transplantation studies. Longitudinal interventions are being conducted in AD, PD, amyotrophic lateral sclerosis, Huntington's disease, and multiple sclerosis. Neurodevelopmental research has also seen a boon in microbiome-related clinical research including in autism, Attention-deficit/hyperactivity disorder, and schizophrenia, which is confirming prior animal model work regarding the key time-windows in the gut microbiome important for infant cognition. While recent research advances represent important progress, fundamental knowledge gaps and obstacles remain. Knowing how and why the gut microbiome changes at the extremes of life will develop our mechanistic understanding and help build the evidence base as we strive toward counteracting microbial missteps with precision therapeutic interventions.

Ethnic disparity in diagnosing asymptomatic bacterial vaginosis using machine learning

While machine learning (ML) has shown great promise in medical diagnostics, a major challenge is that ML models do not always perform equally well among ethnic groups. This is alarming for women's health, as there are already existing health disparities that vary by ethnicity. Bacterial Vaginosis (BV) is a common vaginal syndrome among women of reproductive age and has clear diagnostic differences among ethnic groups. Here, we investigate the ability of four ML algorithms to diagnose BV. We determine the fairness in the prediction of asymptomatic BV using 16S rRNA sequencing data from Asian, Black, Hispanic, and white women. General purpose ML model performances vary based on ethnicity. When evaluating the metric of false positive or false negative rate, we find that models perform least effectively for Hispanic and Asian women. Models generally have the highest performance for white women and the lowest for Asian women. These findings demonstrate a need for improved methodologies to increase model fairness for predicting BV.

Mechanistic Assessment of Anise Seeds and Clove Buds against the Neurotoxicity Caused by Metronidazole in Rats: Possible Role of Antioxidants, Neurotransmitters, and Cytokines

Long-term use of the nitroimidazole-derived antibiotic metronidazole has been associated with neuronal damage due to its ability to cross the blood-brain barrier. Polyphenol-rich plants, such as anise seeds and clove buds, are suggested to have neuroprotective effects. However, their intracellular protective pathway against metronidazole-induced neurotoxicity remains unexplored. This study aims to evaluate the potential neuroprotective benefits of anise seeds and clove buds and elucidate the proposed metronidazole-induced neurotoxicity mechanism. This study divided rats into six groups, each containing six rats. In Group I, the control group, rats were administered saline orally. Group II rats received 200 mg/kg of metronidazole orally. Group III rats received 250 mg/kg b.w. of anise seed extract and metronidazole. Group IV rats received 500 mg/kg b.w. of anise seed extract (administered orally) and metronidazole. Group V rats received 250 mg/kg b.w. of clove bud extract (administered orally) and metronidazole. Group VI rats were administered 500 mg/kg b.w. of clove bud extract and metronidazole daily for 30 consecutive days. The study evaluated the phenolic compounds of anise seeds and clove buds. Moreover, it assessed the inflammatory and antioxidant indicators and neurotransmitter activity in brain tissues. A histological examination of the brain tissues was conducted to identify neuronal degeneration, brain antioxidants, and apoptotic mRNA expression. The study found that metronidazole treatment significantly altered antioxidant levels, inflammatory mediators, and structural changes in brain tissue. Metronidazole also induced apoptosis in brain tissue and escalated the levels of inflammatory cytokines. Oral administration of metronidazole resulted in a decrease in GABA, dopamine, and serotonin and an increase in ACHE in brain tissue. Conversely, oral administration of anise and clove extracts mitigated the harmful effects of metronidazole. The neurotoxic effects of metronidazole appear to stem from its ability to reduce antioxidants in brain tissue and increase nitric oxide production and apoptosis. The study concludes that neuronal damage caused by metronidazole is significantly mitigated by treatment with anise and clove extracts.

Enterobacter ludwigii protects DSS-induced colitis through choline-mediated immune tolerance

Commensal intestinal bacteria play key roles in regulating host immune tolerance; however, bacterial strains and related metabolites directly involved in this regulation are largely unknown. Here, using a mouse model of dextran sulfate sodium (DSS)-induced colitis combined with different antibiotic treatment, Enterobacter ludwigii, abundant in microbiota of mice treated with metronidazole, is screened out to have prophylactic and therapeutic effects on DSS-induced colitis with or without the presence of complex intestinal bacteria. E. ludwigii is found to induce CD103+DC and regulatory T (Treg)-mediated immune tolerance for colitis remission using in vitro and in vivo experiments. Moreover, choline, one metabolite of E. ludwigii, is identified to increase dendritic cells' (DCs) immune tolerance to promote Treg differentiation. E. ludwigii is found to induce DCs' immune tolerance ability for Treg differentiation through choline and α7nAChR-mediated retinoic acid (RA) and transforming growth factor beta (TGF-β) upregulation, resulting in protecting mice against DSS-induced colitis. This study suggests potential therapeutic approaches for inflammatory bowel diseases (IBDs).

Metronidazole-Induced Toxic Neuropathy With the "Boomerang" Sign: A Case Report

BACKGROUND

Metronidazole has been used to treat a broad range of infections over the decades, and its safety profile has been presumably well studied. However, neurological severe adverse events after prescription and nonprescription use of metronidazole is well recognized but underdiagnosed.

CASE PRESENTATION

We report the case of a 48-year-old Indian man who presented with unremitting symptoms of peripheral neuropathy along with a silent callosal lesion in the splenium ("boomerang" sign). Because he had visited 3 neurologists previously, there were many targeted and nontargeted investigations, which failed to reach an etiological diagnosis and hence to provide relief. The patient was questioned about a potential neurotoxin exposure, and at this point, he said that he was taking metronidazole for a long time, without any supervision, as an over-the-counter remedy for self-diagnosed "chronic amebiasis." On stopping metronidazole, he recovered gradually. In the sixth month of follow-up, brain magnetic resonance imaging showed disappearance of the callosal lesion and significant improvement in the nerve conduction studies.

CONCLUSIONS

Clinicians should keep metronidazole toxicity in mind while dealing with a case of cytotoxic lesion of the corpus callosum with splenium involvement and peripheral neuropathy.

Metronidazole-associated Neurologic Events: A Nested Case-control Study

BACKGROUND

Case reports have described instances of peripheral and central nervous system toxicity during treatment with metronidazole; however, no large-scale studies have examined this association.

METHODS

We conducted a population-based nested case-control study of adults aged 66 years or older living in Ontario, Canada, between 1 April 2003 and 31 March 2017. Cases were individuals who attended hospital for any of cerebellar dysfunction, encephalopathy, or peripheral neuropathy within 100 days of a prescription for either metronidazole or clindamycin. We matched each case patient with up to 10 event-free control subjects who also received metronidazole or clindamycin. We used conditional logistic regression to test the association between metronidazole exposure and neurologic events, with clindamycin as the reference exposure.

RESULTS

We identified 1212 cases with recent use of either metronidazole or clindamycin and 12 098 controls. Neurologic adverse events were associated with an increased odds of metronidazole exposure compared to clindamycin (odds ratio [OR], 1.72 [95% confidence interval {CI}, 1.53-1.94]), which persisted after accounting for patient demographics, comorbidities, and other medication exposures (adjusted odds ratio [aOR], 1.43 [95% CI, 1.26-1.63]). We found a consistent association limited to either central (aOR, 1.46 [95% CI, 1.27-1.68]) or peripheral (aOR, 1.34 [95% CI, 1.02-1.76]) nervous system events. Among metronidazole recipients, the overall incidence of neurologic events at 100 days was approximately 0.25%.

CONCLUSIONS

Metronidazole is associated with an increased risk of adverse peripheral and central nervous system events relative to clindamycin. Clinicians and patients should be aware of these rare but potentially serious adverse events.

Metronidazole-induced reversible cerebellar dysfunction

A 73-year-old man who presented with fever and abdominal discomfort was diagnosed to have a liver abscess. He was treated with antimicrobials which included metronidazole. One month into treatment, he developed neurological symptoms and signs that were suggestive of cerebellar pathology. MRI of the brain showed T2/fluid attenuated inversion recovery hyperintensities involving bilateral dentate, fastigial and interpositus nuclei. After excluding common aetiologies, the possibility of metronidazole-induced neurotoxicity was considered. After stopping metronidazole, his symptoms and signs resolved. A subsequent MRI scan of the brain showed reversal of changes. Neurotoxicity caused by metronidazole is an uncommon adverse effect of a commonly used antimicrobial drug and should be considered in the appropriate clinical scenario.

Reversible optic neuropathy secondary to metronidazole

Metronidazole is a nitroimidazole antibiotic used in treating anaerobic bacteria and protozoal infections. It was first licensed for the treatment of Trichomonas vaginalis but is now used in the management of various gastrointestinal and genitourinary infections. Many neurological side effects are well documented, although there is scarce literature illustrating optic neuropathy secondary to metronidazole. We describe a case report of a 36-year-old man who presented with symptomatically reduced central visual loss on a background of a 2-year history of metronidazole use for a perianal fistula. Electrophysiology demonstrated bilateral optic neuropathy, with pattern visual evoked potential traces demonstrating marked latency and small amplitude responses of the P100 waves, which improved to within normal limits on cessation of metronidazole. This case study demonstrates clinical and electrophysiological reversibility of optic neuropathy secondary to high dose and prolonged metronidazole use.

Aspiration Risk Factors, Microbiology, and Empiric Antibiotics for Patients Hospitalized With Community-Acquired Pneumonia

BACKGROUND

Aspiration community-acquired pneumonia (ACAP) and community-acquired pneumonia (CAP) in patients with aspiration risk factors (AspRFs) are infections associated with anaerobes, but limited evidence suggests their pathogenic role.

RESEARCH QUESTION

What are the aspiration risk factors, microbiology patterns, and empiric anti-anaerobic use in patients hospitalized with CAP?

STUDY DESIGN AND METHODS

This is a secondary analysis of GLIMP, an international, multicenter, point-prevalence study of adults hospitalized with CAP. Patients were stratified into three groups: (1) ACAP, (2) CAP/AspRF+ (CAP with AspRF), and (3) CAP/AspRF- (CAP without AspRF). Data on demographics, comorbidities, microbiological results, and anti-anaerobic antibiotics were analyzed in all groups. Patients were further stratified in severe and nonsevere CAP groups.

RESULTS

We enrolled 2,606 patients with CAP, of which 193 (7.4%) had ACAP. Risk factors independently associated with ACAP were male, bedridden, underweight, a nursing home resident, and having a history of stroke, dementia, mental illness, and enteral tube feeding. Among non-ACAP patients, 1,709 (70.8%) had CAP/AspRF+ and 704 (29.2%) had CAP/AspRF-. Microbiology patterns including anaerobes were similar between CAP/AspRF-, CAP/AspRF+ and ACAP (0.0% vs 1.03% vs 1.64%). Patients with severe ACAP had higher rates of total gram-negative bacteria (64.3% vs 44.3% vs 33.3%, P = .021) and lower rates of total gram-positive bacteria (7.1% vs 38.1% vs 50.0%, P < .001) when compared with patients with severe CAP/AspRF+ and severe CAP/AspRF-, respectively. Most patients (>50% in all groups) independent of AspRFs or ACAP received specific or broad-spectrum anti-anaerobic coverage antibiotics.

INTERPRETATION

Hospitalized patients with ACAP or CAP/AspRF+ had similar anaerobic flora compared with patients without aspiration risk factors. Gram-negative bacteria were more prevalent in patients with severe ACAP. Despite having similar microbiological flora between groups, a large proportion of CAP patients received anti-anaerobic antibiotic coverage.

Bismuth Concentrations in Patients Treated in Real-Life Practice with a Bismuth Subcitrate-Metronidazole-Tetracycline Preparation: The SAPHARY Study

INTRODUCTION

A fixed-dose association of bismuth subcitrate, metronidazole and tetracycline (BMT) (Pylera^®, Allergan, NJ, USA) was made available in France in 2013 for the eradication of Helicobacter pylori. Due to a historical issue of bismuth encephalopathy, the French Health Authorities requested a study of blood and plasma bismuth concentrations with BMT in daily practice.

AIMS

The aim of the study was to measure eventual bismuth accumulation and neurological toxicity in patients prescribed BMT.

METHODS

Patients initiating BMT for H. pylori between March 2014 and December 2015 were included. A blood sample was taken before first BMT intake and 24 h after the last intake, for assay of bismuth. A concentration > 50 μg/L was considered abnormal. Neurological complaints were assessed at inclusion, at the end of the 10-day treatment course, and 28 days later.

RESULTS

202 patients were included, of whom 190 took at least one dose of BMT, and 167 provided both required blood samples. Mean blood bismuth concentrations after the BMT course were 16.9 μg/L (95% confidence interval 15.6-18.3). Concentrations were > 50 μg/L (56.0 μg/L and 50.9 μg/L) in two elderly patients, one of whom presented mild, transient memory impairment during treatment. Non-serious neurological symptoms occurred in 20% of all patients and treatment failure was documented in 5% of patients.

CONCLUSIONS

In this study measuring blood bismuth concentrations in real-life practice, in < 1% of patients the BMT course resulted in blood bismuth concentrations > 50 μg/L. No serious neurological adverse events were observed.

STUDY REGISTRATION

EU-PAS register EUPAS3142 at www.encepp.eu ; ENCePP study seal.

Emerging drugs for the treatment of clostridium difficile

INTRODUCTION

Clostridium difficile or Clostridioides difficile (C. difficile) infection represents the most common cause of healthcare-associated infection. Over the last decades, the incidence and severity of C. difficile infection is rapidly increasing, with a significant impact on morbidity and mortality, and burden on health care system. Orally administered vancomycin and fidaxomicin are the therapeutic options of choice for initial C. difficile infection and fecal microbiota transplant for the recurrence infection. Furthermore, in recent years several new antibiotics with narrow-spectrum activity and low intestinal resorption have been developed, including surotomycin, cadazolid, and ridinilazol, and novel toxoid vaccines are expected to be efficacious in the prevention of C. difficile infection. Areas covered: Literature review was performed to select publications about current guidelines and phase-II/III trials on emerging drugs. These include novel antibiotics, monoclonal antibodies, vaccines, and fecal microbiota transplantation. Expert opinion: We have today a wide spectrum of promising therapeutic possibilities against infection. Pivotal future clinical trials may be crucial in developing effective strategies to optimize outcomes, mainly in high-risk population.

Management of Primary and Recurrent Clostridium difficile Infection: An Update

Background: Clostridium difficile infection (CDI) is one of the most common healthcare-associated infections (HAI) in the United States and Canada, and incidence rates have increased worldwide in recent decades. Currently, antibiotics are the mainstay treatments for both primary and recurrent CDI, but their efficacy is limited, prompting further therapies to be developed. Aim: This review summarizes current and emerging therapies in CDI management including antibiotics, fecal microbiota transplantation, monoclonal antibodies, spore-based therapies, and vaccinations.

Systemic Metronidazole May Not Reduce Posthemorrhoidectomy Pain: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Hemorrhoidectomy is associated with significant postoperative pain. Oral metronidazole has been recommended as an adjunct to improve posthemorrhoidectomy analgesia.

OBJECTIVE

This study aimed to evaluate the impact of oral metronidazole on patient-reported pain following hemorrhoidectomy.

DATA SOURCES

We conducted a systematic search in the MEDLINE, EMBASE, ISI Web of Science, and Cochrane Central Register of Controlled Trials databases.

STUDY SELECTION

Randomized controlled trials examining adults who underwent surgical hemorrhoidectomy were included. Participants in an active intervention group received oral metronidazole postoperatively, and those in a control group received placebo or usual care. Postoperative pain was assessed for at least 3 days postoperatively.

INTERVENTION

A random-effects model was used.

MAIN OUTCOMES MEASURES

The primary outcome was pain during the first 2 postoperative weeks, measured on a visual analogue scale. The secondary outcome was time to return to normal activities.

RESULTS

Patients who received oral metronidazole had significantly lower reported pain scores on postoperative day 1 (standardized mean difference, -0.87 ± 0.44; 95% CI, -1.73 to -0.015; p = 0.046; n = 4) and day 4 (standardized mean difference, -1.43 ± 0.71; 95% CI, -2.83 to -0.037; p = 0.044; n = 3). Metronidazole use was associated with a significantly shorter time to return to normal activities (standardized mean difference, -0.76 ± 0.34; 95% CI, -1.43 to -0.088, p = 0.027). The improvements disappeared in a sensitivity analysis excluding the largest trial with a high risk of bias, and no significance was observed during the remaining postoperative days.

LIMITATIONS

The meta-analysis was limited by lack of double blinding, absence of a placebo, and unclear or high risk of bias in a proportion of the included trials.

CONCLUSIONS

Although a favorable adverse effect profile supports consideration of oral metronidazole to reduce posthemorrhoidectomy pain, pooled analysis reveals inconsistent results with no pain reduction on most postoperative days. The current recommendation for routine prescription of oral metronidazole should be reevaluated in the absence of additional well-designed trials.

Role of antibiotics for treatment of inflammatory bowel disease

Inflammatory bowel disease is thought to be caused by an aberrant immune response to gut bacteria in a genetically susceptible host. The gut microbiota plays an important role in the pathogenesis and complications of the two main inflammatory bowel diseases: Crohn’s disease (CD) and ulcerative colitis. Alterations in gut microbiota, and specifically reduced intestinal microbial diversity, have been found to be associated with chronic gut inflammation in these disorders. Specific bacterial pathogens, such as virulent Escherichia coli strains, Bacteroides spp, and Mycobacterium avium subspecies paratuberculosis, have been linked to the pathogenesis of inflammatory bowel disease. Antibiotics may influence the course of these diseases by decreasing concentrations of bacteria in the gut lumen and altering the composition of intestinal microbiota. Different antibiotics, including ciprofloxacin, metronidazole, the combination of both, rifaximin, and anti-tuberculous regimens have been evaluated in clinical trials for the treatment of inflammatory bowel disease. For the treatment of active luminal CD, antibiotics may have a modest effect in decreasing disease activity and achieving remission, and are more effective in patients with disease involving the colon. Rifamixin, a non absorbable rifamycin has shown promising results. Treatment of suppurative complications of CD such as abscesses and fistulas, includes drainage and antibiotic therapy, most often ciprofloxacin, metronidazole, or a combination of both. Antibiotics might also play a role in maintenance of remission and prevention of post operative recurrence of CD. Data is more sparse for ulcerative colitis, and mostly consists of small trials evaluating ciprofloxacin, metronidazole and rifaximin. Most trials did not show a benefit for the treatment of active ulcerative colitis with antibiotics, though 2 meta-analyses concluded that antibiotic therapy is associated with a modest improvement in clinical symptoms. Antibiotics show a clinical benefit when used for the treatment of pouchitis. The downsides of antibiotic treatment, especially with recurrent or prolonged courses such as used in inflammatory bowel disease, are significant side effects that often cause intolerance to treatment, Clostridium dificile infection, and increasing antibiotic resistance. More studies are needed to define the exact role of antibiotics in inflammatory bowel diseases.

Drug-induced cerebellar ataxia: a systematic review

BACKGROUND AND OBJECTIVES

Cerebellar ataxia can be induced by a large number of drugs. We here conducted a systemic review of the drugs that can lead to cerebellar ataxia as an adverse drug reaction (ADR).

METHODS

We performed a systematic literature search in Pubmed (1966 to January 2014) and EMBASE (1988 to January 2014) to identify all of the drugs that can have ataxia as an ADR and to assess the frequency of drug-induced ataxia for individual drugs. Furthermore, we collected reports of drug-induced ataxia over the past 20 years in the Netherlands by querying a national register of ADRs.

RESULTS

Drug-induced ataxia was reported in association with 93 individual drugs (57 from the literature, 36 from the Dutch registry). The most common groups were antiepileptic drugs, benzodiazepines, and antineoplastics. For some, the number needed to harm was below 10. Ataxia was commonly reversible, but persistent symptoms were described with lithium and certain antineoplastics.

CONCLUSIONS

It is important to be aware of the possibility that ataxia might be drug-induced, and for some drugs the relative frequency of this particular ADR is high. In most patients, symptoms occur within days or weeks after the introduction of a new drug or an increase in dose. In general, ataxia tends to disappear after discontinuation of the drug, but chronic ataxia has been described for some drugs.

Bacteriology of aspiration pneumonia in patients with acute coma

Loss of protective airway reflexes in patients with acute coma puts these patients at risk of aspiration pneumonia complicating the course of the primary disease. Available data vary considerably with regard to bacteriology, role of anaerobic bacteria, and antibiotic treatment. Our objective was to research the bacteriology of aspiration pneumonia in acute coma patients who were not pre-treated with antibiotics or hospitalized within 30 days prior to the event. We prospectively analyzed 127 patient records from adult patients admitted, intubated and ventilated to a tertiary medical intensive care unit with acute coma. Bacteriology and antibiotic resistance testing from tracheal aspirate sampled within 24 h after admission, blood cultures, ICU scores (APACHE II, SOFA), hematology, and clinical chemistry were assessed. Patients were followed up until death or hospital discharge. The majority of patients with acute coma suffered from acute cardiovascular disorders, predominantly myocardial infarction, followed by poisonings, and coma of unknown cause. In a majority of our patients, microaspiration resulted in overt infection. Most frequently S. aureus, H. influenzae, and S. pneumoniae were isolated. Anaerobic bacteria (Bacteroides spec., Fusobacteria, Prevotella spec.) were isolated from tracheal aspirate in a minority of patients, and predominantly as part of a mixed infection. Antibiotic monotherapy with a 2nd generation cephalosporin, or a 3rd generation gyrase inhibitor, was most effective in our patients regardless of the presence of anaerobic bacteria.