Metronidazole-induced encephalopathy in a patient with Crohn's disease

Antibiotic-induced neuropsychiatric toxicity: epidemiology, mechanisms and management strategies - a narrative literature review

Antibiotics are amongst the most prescribed medications globally in both inpatient and outpatient settings. Antibiotic-induced neuropsychiatric toxicity is relatively uncommon; yet, when it occurs, it can lead to severe morbidity ranging from dizziness and confusion to seizure and psychosis. However, the actual incidence rate of these adverse events may be higher due to underdiagnosis or misdiagnosis as they are commonly confused with clinical manifestations of different neuropsychiatric conditions. The incidence and mechanism of antibiotic-induced neuropsychiatric toxicity vary between different antibiotic classes and clinical presentation (i.e. neurotoxicity versus psychiatric toxicity). However, the exact mechanism by which antibiotics can cause neuropsychiatric toxicity remains unclear. This article reviews the epidemiology of antibiotic-induced neuropsychiatric toxicity, explores potential mechanisms of this adverse event, investigates variations in frequency and clinical presentations between different antibiotic classes causing neuropsychiatric toxicity, and discusses management strategies.

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.

Diffuse subcortical white matter restriction: An uncommon finding on metronidazole toxicity

Metronidazole is a common and widely used antibiotic to treat a wide range of infectious diseases and has been associated with serious neurologic disturbances which in some cases were irreversible. We present a metronidazole-induced encephalopathy in a 19-year-old girl after 7 days of metronidazole treatment, with diffusion restricted subcortical white matter lesions along with the corpus callosum involvements. Diverse clinical presentation of a serious neurologic disturbance caused by a common widely used antibiotic should be carefully addressed in the setting of both short- and long-term treatment.

S, Siddiqui SA, Gupta A, Pathak V, Mulani M, Khan S, Bansal T. MRI Findings and Topographic Distribution of Lesions in Metronidazole-Induced Encephalopathy

Purpose

This study aims to describe the magnetic resonance imaging (MRI) of the brain of five patients diagnosed with metronidazole-induced encephalopathy (MIE). In addition, the aim of our study was to better define the topographic distribution of lesions in MIE.

Methods

We retrospectively evaluated MRI findings before and after drug cessation in five patients diagnosed with MIE at Era’s Lucknow Medical College and Hospital, Lucknow, Uttar Pradesh, India. The main MRI signal changes and lesion locations were studied.

Results

Among the patients observed, the average age of the patients with MIE was 55 years (range: 30-70 years). Cerebellar dysfunction, mainly ataxia, and altered mental status were seen in the majority of cases. The most frequently involved sites were the dentate nucleus (cerebellum), brain stem, and corpus callosum (splenium). In diffusion-weighted imaging (DWI), most lesions did not show true restricted diffusion, except for a solitary corpus callosum lesion.

Conclusion

Although drug-related side effects are more common with long-term use of metronidazole, they may also occur with high doses for short durations. The dentate nucleus, the splenium in the corpus callosum, and the brain stem are the most affected structures. Apart from a solitary lesion of the corpus callosum, all identified lesions were reversible at follow-up MRI after discontinuation of metronidazole. The clinical presentation and characteristic MRI changes are highly specific and can be correlated to make a rapid and more accurate diagnosis of this potentially treatable condition. Prognosis is excellent if detected early.

The Influence of Omeprazole on the Dissolution Processes of pH-Dependent Magnetic Tablets Assessed by Pharmacomagnetography

Pharmacomagnetography involves the simultaneous assessment of solid dosage forms (SDFs) in the human gastrointestinal (GI) tract and the drug plasmatic concentration, using a biomagnetic technique and pharmacokinetics analysis. This multi-instrumental approach helps the evaluation, as GI variables can interfere with the drug delivery processes. This study aimed to employ pharmacomagnetography to evaluate the influence of omeprazole on the drug release and absorption of metronidazole administered orally in magnetic-coated tablets. Magnetic-coated tablets, coated with Eudragit^® E-100 (E100) and containing 100 mg of metronidazole, were produced. For the in vivo experiments, 12 volunteers participated in the two phases of the study (placebo and omeprazole) on different days to assess the bioavailability of metronidazole. The results indicated a shift as the pH of the solution increased and a delay in the dissolution of metronidazole, showing that the pH increase interferes with the release processes of tablets coated with E100. Our study reinforced the advantages of pharmacomagnetography as a tool to perform a multi-instrumental correlation analysis of the disintegration process and the bioavailability of drugs.

Gut microbiota mediates intermittent-fasting alleviation of diabetes-induced cognitive impairment

Cognitive decline is one of the complications of type 2 diabetes (T2D). Intermittent fasting (IF) is a promising dietary intervention for alleviating T2D symptoms, but its protective effect on diabetes-driven cognitive dysfunction remains elusive. Here, we find that a 28-day IF regimen for diabetic mice improves behavioral impairment via a microbiota-metabolites-brain axis: IF enhances mitochondrial biogenesis and energy metabolism gene expression in hippocampus, re-structures the gut microbiota, and improves microbial metabolites that are related to cognitive function. Moreover, strong connections are observed between IF affected genes, microbiota and metabolites, as assessed by integrative modelling. Removing gut microbiota with antibiotics partly abolishes the neuroprotective effects of IF. Administration of 3-indolepropionic acid, serotonin, short chain fatty acids or tauroursodeoxycholic acid shows a similar effect to IF in terms of improving cognitive function. Together, our study purports the microbiota-metabolites-brain axis as a mechanism that can enable therapeutic strategies against metabolism-implicated cognitive pathophysiologies.

Intermittent fasting (IF) has been shown beneficial in reducing metabolic diseases. Here, using a multi-omics approach in a T2D mouse model, the authors report that IF alters the composition of the gut microbiota and improves metabolic phenotypes that correlate with cognitive behavior.

An update on treatment options for primary sclerosing cholangitis

Primary sclerosing cholangitis is a chronic cholestatic liver disease defined by strictures of the biliary tree which could ultimately lead to liver cirrhosis and cholangiocarcinoma. Although the exact underlying etiology of this disorder is not fully understood, the pathology is believed to be caused by immune mediated mechanisms. Growing body of evidence suggests several treatment modalities mainly focusing on the inflammation aspect of this disorder. However, there is still no consensus regarding the best treatment option for these patients. Thus, the present study aimed to review the current treatment options for patients with primary sclerosing cholangitis.

Anti-protozoal Activity of Conifer Green Needle Complex against Trichomonas vaginalis

Treatment of Trichomonas vaginalis typically involves using nitroimidazoles (such as metronidazole and tinidazole). Some T. vaginalis strains have become resistant to these drugs, so the development of new drugs is necessary. Clinical samples were taken from 80 males and 70 females (aged 17–45). The sensitivity of T. vaginalis in these samples to CGNC (100, 200, 300 and 500 mg/mL) and metronidazole (10, 15, 25 and 50 μg/mL) was evaluated. All 10 isolates were sensitive to at least one concentration of CGNC. Three strains were sensitive (all cells were killed) to 100 mg/mL CGNC, while there was a decrease in the number of Trichomonas present in the other samples when compared with the control. Six strains were sensitive to 200 mg/mL CGNC, while those strains that grew in the presence of CGNC showed a reduction in numbers when compared with the control. Nine strains were sensitive to 300 mg/mL CGNC. The strain not sensitive to 300 mg/mL CGNC showed a decrease in the number of Trichomonas present (<102 cells/mL) when compared to the control (104 cells/mL). All strains were sensitive to 500 mg/mL CGNC. Three strains (one motile and two non-motile) were sensitive to all concentrations of CGNC and one of the non-motile strains was resistant (MIC 50 μg/mL) to metronidazole. The other two strains were moderately resistant (MIC 15 and 25 μg/mL) to metronidazole. Of the 10 Trichomonas strains, four were resistant to metronidazole (MIC 50 μg/mL) and sensitive to at least one concentration of CGNC. CGNC may be used as a treatment for T. vaginalis infections and should be considered for clinical strains resistant to metronidazole.

Reversible metronidazole-induced neurotoxicity after 10 weeks of therapy

Metronidazole is a commonly used antimicrobial worldwide. The most common side effects that have been reported are nausea, vomiting and hypersensitivity reactions. However, neurotoxicity has been reported with the use of metronidazole but rather rare. The most common neurological manifestation is peripheral neuropathy involvement in the form of sensory loss. It is worth mentioning that central neurotoxicity is a rare side effect of metronidazole use but reversible. The manifestations vary from a headache, altered mental status to focal neurological deficits. The diagnosis is mainly by neuroimaging in the setting of acute neurological change in the patient status. Here, we report a case of metronidazole-induced neurotoxicity in a 38-year-old male patient who was admitted with a brain abscess and was started on metronidazole for more than 10 weeks.