Metronidazole-induced neurotoxicity

Association Between First-time Neurologic Events and Metronidazole Treatment: A Case-time Control Study

PURPOSE

Metronidazole, a widely used antimicrobial medication, has been linked to neurologic adverse drug reactions. This study investigates the association between metronidazole use and first-time neurologic events.

METHODS

We conducted a case-time-control study using data from the Danish National Patient Register and the National Prescription Register in years 2013 to 2021. Patients with a first-time diagnosis of encephalopathy, cerebellar dysfunction, or peripheral neuropathy were included. Conditional logistic regression analyses were performed to estimate the risk of neurologic events associated with metronidazole use.

FINDINGS

Out of 476,066 first-time metronidazole prescriptions, the 100-day cumulative incidence of peripheral neuropathy was 0.016%, and 0.002% for cerebellar dysfunction or encephalopathy. In the case-time control study, we identified 17,667 persons with a first-time neurologic event and were included for the analysis. The estimated odds ratio for the combined neurologic events was 0.98 (95% CI, 0.59-1.64, P = 0.95) with no statistically significant association across different subgroups and time windows.

IMPLICATIONS

Our findings suggest that metronidazole-induced neurologic events may be rarer than previously described, and we did not find any consistent or statistically significant association between metronidazole exposure. Nonetheless, clinicians should remain vigilant to potential neurologic risks in patients receiving metronidazole, to ensure its safe and effective use.

Exacerbation of Mania due to Metronidazole in a Bipolar Disorder

Bipolar disorder is a mental health disorder where the patient experiences extreme shifts in mood marked by depression, mania, or hypomania. It affects their overall daily life activities and sleep patterns. This case report is of a 74-year-old female patient with bipolar disorder who experienced a manic episode after initiation of antibiotics to treat gallbladder perforation with abscess formation. The patient's past medical history included Parkinson's disease, diabetes mellitus, bipolar disorder, and acalculous cholecystitis. The patient required hospitalization for a cholecystostomy tube insertion for drainage. During hospitalization, the patient was started on empiric treatment with broad-spectrum antibiotics, including piperacillin/tazobactam and metronidazole. The patient remained stable during the inpatient stay and was discharged home one week later. She was prescribed cefuroxime and metronidazole to complete a 2-week duration of antibiotics. However, upon discharge, she developed manic symptoms, including lack of need to sleep, excessive talking, and severe agitation. Upon assessment, the psychiatric team decided to hold metronidazole as it has an adverse effect of mania as evidenced in drug information resources. The patient started to show immediate recovery from the symptoms with complete resolution of manic symptoms on the 3^rd day following the discontinuation of metronidazole. This case emphasizes the increased need for vigilance in bipolar patients upon prescribing metronidazole. Also, further research is needed to predict the time to onset of manic symptoms and improvement in patient symptoms upon drug discontinuation.

Identifying Acute Neuropsychiatric Events in Children and Adolescents

OBJECTIVES

The objective of this study was to develop and validate an approach to accurately identify incident pediatric neuropsychiatric events (NPEs) requiring hospitalization by using administrative data.

METHODS

We performed a cross-sectional, multicenter study of children 5 to 18 years of age hospitalized at two US children's hospitals with an NPE. We developed and evaluated 3 NPE identification algorithms: (1) primary or secondary NPE International Classification of Diseases, 10th Revision diagnosis alone, (2) NPE diagnosis, the NPE was present on admission, and the primary diagnosis was not malignancy- or surgery-related, and (3) identical to algorithm 2 but without requiring the NPE be present on admission. The positive predictive value (PPV) of each algorithm was calculated overall and by diagnosis field (primary or secondary), clinical significance, and NPE subtype.

RESULTS

There were 1098 NPE hospitalizations included in the study. A total of 857 confirmed NPEs were identified for algorithm 1, yielding a PPV of 0.78 (95% confidence interval [CI] 0.76-0.80). Algorithm 2 (n = 846) had an overall PPV of 0.89 (95% CI 0.87-0.91). For algorithm 3 (n = 938), the overall PPV was 0.86 (95% CI 0.83-0.88). PPVs varied by diagnosis order, NPE clinical significance, and subtype. The PPV for critical clinical significance was 0.99 (0.97-0.99) for all 3 algorithms.

CONCLUSIONS

We identified a highly accurate method to identify neuropsychiatric adverse events in children and adolescents. The use of these approaches will improve the rigor of future studies of NPE, including the necessary evaluations of medication adverse events, infections, and chronic conditions.