Metronidazole hypersensitivity

Metronidazole Induced Cutaneous Adverse Drug Reaction- A Systematic Review of Descriptive Studies

BACKGROUND

A substantial number of research studies on metronidazole-related cutaneous symptoms have recently been published. Our objective was to identify and evaluate descriptive studies that described metronidazole-related skin manifestations, therapeutic interventions, and consequences.

METHODS

A comprehensive literature search was carried out in the PubMed, Scopus, and grey literature databases from inception to April 2022 without any constraints, as well as a snowball search in Google and a search in Google Scholar. Descriptive articles describing metronidazole-related cutaneous manifestations were considered for the review. Two distinct reviewers carried out the research selection, data extraction, and quality assessment; any discrepancies were resolved by consensus with the third reviewer.

RESULTS

About 24 out of 4648 descriptive studies, including 26 patients (20 Female patients and 6 male patients), were included in this review. The included studies comprised a range of ages from 16 to 78 years old. Metronidazole was indicated for the treatment of bacterial vaginosis, trichomoniasis, sepsis, anti-infection therapy, perforated appendicitis, rosacea, vaginal discharge, dysentery, acne rosacea, trichomonal vaginitis, lichen planus, liver abscess, facial rosacea, intestinal amoebiasis, and gingivitis. Fixed drug eruption was the most common skin manifestation which was reported in 7 cases included in this review. Cutaneous manifestations were ameliorated by cessation of the offending drug and by apportioning antihistamines, topical steroids, parenteral corticosteroids, emollients, and topical moisturizers.

CONCLUSION

Clinicians and healthcare professionals should be cognizant of the potential cutaneous adverse drug reactions (CADRs) induced by metronidazole to mitigate fatal circumstances. The management of the CADRs appears to respond effectively with immediate drug discontinuation and supportive therapy.

Maintenance of Remission after Oral Metronidazole Add-on Therapy in Rosacea Treatment: A Retrospective, Comparative Study

BACKGROUND

Rosacea is a chronic inflammatory disease which requires treatment to maintain remission.

OBJECTIVE

Recently, the effect of Demodex mites in recurrence of rosacea has been described. Although there is limited data, previous reports have suggested that oral metronidazole demonstrated efficacy in treatment of rosacea.

METHODS

Fifty-eight Korean patients with rosacea who received treatment with oral minocycline (50 mg twice daily) only or with two-week of oral metronidazole (250 mg thrice daily) were evaluated retrospectively. Their responses were evaluated by Investigator's Global Assessment (IGA), Clinician's Erythema Assessment (CEA), and patient's Global Assessment. The recurrence rate and odds ratio of risk factors for recurrence were also estimated.

RESULTS

The combination treatment group reported earlier clinical improvement and lower mean IGA and CEA than the monotherapy group. Approximately 48% of patients with combination treatment did not show relapse within 24 weeks, which is significantly higher than that in the monotherapy group (p=0.042).

CONCLUSION

Add-on therapy of oral metronidazole appeared to be a significant protective factor for recurrence of rosacea (p<0.05). This study suggests that oral metronidazole can be added to oral minocycline to reduce relapses in rosacea patients with tolerable safety.

Diagnostic workup including CD203c-based basophil activation test in immediate hypersensitivity due to metronidazole and ornidazole and evaluation of cross-reactivity in between

BACKGROUND

Little is known about the diagnostic approaches for immediate hypersensitivity reactions (IHRs) due to 5-nitroimidazole antibiotics. The aim was to evaluate the usefulness of in vivo tests and basophil activation test (BAT) for the diagnosis of IHRs due to metronidazole and ornidazole and to determine possible cross-reactivity in between.

METHODS

Forty-nine patients with a clear history of IHRs due to these drugs and 20 healthy subjects who were known to tolerate these drugs were included. Skin tests (STs) and single-blind placebo-controlled drug provocation tests (SBPCDPTs) were performed with both drugs whereas BAT was applied only with the culprit drug.

RESULTS

The most and least common reaction types were urticaria/angioedema (34.7%) and anaphylaxis (14.3%), respectively. SBPCDPTs were positive in 15 out of 47 patients, and only 7 had positive STs. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of STs for metronidazole/ornidazole were 33.3%/16.6%, 94.2%/97.3%, 60%/50%, and 84.6%/88.1%, respectively. BAT was positive in 12 out of 15 patients and negative in 10 control subjects, giving a sensitivity rate of 71.4% (CI, 29.0%-96.3%) for metronidazole and 83.3% (CI, 35.8%-99.5%) for ornidazole. The optimal concentration of both drugs for BAT was determined as 5 mg/mL. No cross-reactivity among two drugs was observed according to in vivo tests.

CONCLUSIONS

Our study showed that SBPCDPT and BAT are both useful diagnostic tools for IHRs due to 5-nitroimidazole antibiotics and can be used as supplementary to each other. No cross-reactivity between metronidazole and ornidazole in IHRs exists.

A new prodrug and bioactivity evaluation of methotrexate based on Chitosan

Methotrexate (MTX) is the most important drug used in the treatment of several kinds of cancers, such as colon cancer. However, this drug can cause a reduction in the target tissue bioavailability. It is administered orally and absorbed quickly. This study aimed to produce an anti-colon cancer prodrug based on MTX via loading it into a biopolymer compound. Chitosan (CS) was extracted from scales of local fish by utilizing a previously published protocol. The MTX was then transformed to Methotrexate - imidazole and loaded into CS to prepare Chitosan - Methotrexate (CS-MTX) conjugates as colon cancer prodrugs. Fourier-transform infrared (FTIR), UV-visible spectroscopy, and 1H-NMR were used to analyse the structure of the prepared compounds. The prepared compounds were also tested for hemolytic activity. Chemical stability was studied using 0.2 M from the different buffer types with a pH of 1.2 and 7.4 over different periods about 240 min and kept in an incubator at 37 °C. The loading percentage was measured by hydrolysing the amide bond in basic media followed by the measurement of the absorbency at 273 nm. Three types of cancer cells, MCF-7, MDA-MB-231, and MDA-MB-453, were used to test the anticancer effects of CS-MTX by using tetrazolium bromide (MTT) assay. The results indicated that the viability of human breast cancer cell lines decreased because of the use of CS-MTX. This study also showed that CS-MTX was less toxic than the original drug. Therefore, it may be measured for additional biological analyses and medical applications. The results presented here showed that the new compound is remarkably stable in comparison with MTX and has longer half-life (t ½). Therefore, the CS-MTX has promising strategies through minimising the side effects of anti-colon tumour drugs.

Calculated initial parenteral treatment of bacterial infections: Safety and tolerabilty

This is the fourth chapter of the guideline "Calculated initial parenteral treatment of bacterial infections in adults - update 2018" in the 2nd updated version. The German guideline by the Paul-Ehrlich-Gesellschaft für Chemotherapie e.V. (PEG) has been translated to address an international audience. Safety and tolerability of antimicrobial agents will be discussed in this chapter. Toxic, allergic and biological effects can be differentiated on the basis of their pathogenesis. The question of differences in the tolerability of specific antibiotics is of particular importance. However, due to limitations of the available data, it cannot be answered for most agents with the desired accuracy. For an assessment of rare side effects, results from the postmarketing surveillance have to be used.

Trichomonas vaginalis: Clinical relevance, pathogenicity and diagnosis

Trichomonas vaginalis is the etiological agent of trichomoniasis, the most prevalent non-viral sexually transmitted disease worldwide. Trichomoniasis is a widespread, global health concern and occurring at an increasing rate. Infections of the female genital tract can cause a range of symptoms, including vaginitis and cervicitis, while infections in males are generally asymptomatic. The relatively mild symptoms, and lack of evidence for any serious sequelae, have historically led to this disease being under diagnosed, and under researched. However, growing evidence that T. vaginalis infection is associated with other disease states with high morbidity in both men and women has increased the efforts to diagnose and treat patients harboring this parasite. The pathology of trichomoniasis results from damage to the host epithelia, caused by a variety of processes during infection and recent work has highlighted the complex interactions between the parasite and host, commensal microbiome and accompanying symbionts. The commercial release of a number of nucleic acid amplification tests (NAATs) has added to the available diagnostic options. Immunoassay based Point of Care testing is currently available, and a recent initial evaluation of a NAAT Point of Care system has given promising results, which would enable testing and treatment in a single visit.

Symptomatic Trichomonas vaginalis infection in the setting of severe nitroimidazole allergy: successful treatment with boric acid

This report describes a patient with symptomatic Trichomonas vaginalis infection who was unable to tolerate nitroimidazole drugs because of severe hypersensitivity, for which desensitisation was not possible. Use of intravaginal clotrimazole, intravaginal paromomycin, intravaginal furazolidone, povidone–iodine douches, and oral nitazoxanide were unsuccessful in eradicating the patient’s T. vaginalis infection. A 2-month course of intravaginal topical boric acid subsequently achieved a complete symptomatic cure and the patient remained T. vaginalis wet prep- and culture-negative 60 days after treatment.

Triple therapy with ecabet sodium, amoxicillin and lansoprazole for 2 weeks as the rescue regimen for H. pylori infection

BACKGROUND/AIM

Ecabet sodium has an anti-H. pylori effect. We assessed the efficacy of ecabet sodium in the rescue therapy for the eradication of H. pylori.

METHODS

A total of 74 patients with failed eradication of H. pylori after triple therapy with lansoprazole 30 mg bid, amoxicillin 750 mg bid and clarithromycin 200 mg bid were enrolled. They were randomly assigned to the three treatment groups as follows: LAC, lansoprazole 30 mg + amoxicillin 750 mg + clarithromycin 200 mg bid for 1 week; LAC2E, lansoprazole 30 mg bid + amoxicillin 750 mg bid + clarithromycin 200 mg bid + ecabet sodium 2 g bid for 1 week; and LA2E, lansoprazole 30 mg bid + amoxicillin 750 mg bid + ecabet sodium 2 g bid for 2 weeks. Eradication of H. pylori was assessed by the 13C-urea breath test after treatment.

RESULTS

Eradication rates in intention-to-treat and per-protocol analyses were 20.0% (95% CI: 6.8-40.7) and 20.0% (6.8-40.7) with LAC, respectively, and 16.0% (4.5-36.1) and 17.4% (5.0-38.8) with LAC2E. In contrast, respective rates with LA2E were 75% (53.3-90.2) and 85.7% (63.7-97.0), which were significantly higher than those with LAC (p<0.001 for both ITT and PP) and LAC2E (p<0.001 for both ITT and PP).

CONCLUSION

Triple therapy with ecabet sodium, lansoprazole and amoxicillin for 2 weeks was effective as the rescue therapy after failure of the standard clarithromycin-based regimen.

Allergic contact dermatitis to topical antibiotics: Epidemiology, responsible allergens, and management

Topical antibiotics are widely used to treat cutaneous, ocular, and otic infections. Allergic contact dermatitis to topical antibiotics is a rare but well-documented side effect, especially in at-risk populations. The purpose of this article is to review the epidemiology, responsible allergens, and management of allergic contact dermatitis to topical antibiotics.

LEARNING OBJECTIVE

After completing this learning activity, participants should be able to describe the epidemiology of allergic contact dermatitis related to topical antibiotics; show knowledge of the most common allergenic topical antibiotics; and understand the allergenic cross-reactivity pattern amongst topical antibiotics.

Adverse cutaneous reactions to antimicrobials in patients with human immunodeficiency virus infection

Adverse reactions to medication are significant contributors to morbidity and mortality in patients with human immunodeficiency virus (HIV) infection. Cutaneous events not only constitute a significant portion of these reactions, they may also herald developing systemic reactions such as hemato-, nephro-, and hepatotoxicity. The identification of cutaneous adverse reactions and drug culprits and the proper management of reactions are of paramount importance for these patients. This review focuses specifically on adverse cutaneous reactions to antimicrobials that are commonly used in the management of patients with HIV infection.

Hypersensitivity reactions to metronidazole

BACKGROUND

Hypersensitivity reactions to metronidazole are infrequently described. However, we believe that such reactions are increasing due to growing use of the drug for the treatment of amebiasis and anaerobe infections combined with other antibiotics. The present study assesses the need for oral provocation in patients with probable hypersensitivity reactions to metronidazole.

METHODS

We performed cutaneous prick tests with spiramycin and metronidazole as well as epicutaneous tests with metronidazole at different concentrations in four patients with cutaneous reactions to Rhodogil (metronidazole plus spiramicyn). Controlled oral challenges were then carried out with placebo using erythromycin, spiramycin and metronidazole except in the last patient due to a positive prick test.

RESULTS

Only one patient showed a positive metronidazole prick test. The epicutaneous tests were negative. All patients tolerated erythromycin and spiramycin up to therapeutic doses. Oral provocation with metronidazole proved positive, the first patient presenting a delayed exanthema and the other two early erythema and itching.

CONCLUSIONS

We present four cases of cutaneous exanthemas caused by metronidazole (two early and two delayed) and probably mediated by an immune mechanism which we have only been able to demonstrate in one case. Taking into account the low sensitivity of the cutaneous tests (prick tests and epicutaneous tests), oral provocation must be considered the "gold standard" for establishing the diagnosis in many cases of hypersensitivity reactions to metronidazole.

Co-existing sensitivity to metronidazole and isothiazolinone

A 68-year-old woman developed allergic contact dermatitis to topical metronidazole gel as proven by positive patch tests to the gel and to metronidazole. She was also allergic to methylchloroisothiazolinone and methylisothiazolinone (MC/MI). The similarity between the two molecules and the fact that the patient reacted to the gel after the very short incubation period of 1 day (i.e. not long enough for acquiring an active sensitization) makes the possibility of a cross-reaction between these substances very plausible. As the isothiazolinones are widely used and comprise an important and relatively frequent cause of allergic contact dermatitis, a cross-reactivity with metronidazole means that perhaps there should have been more cases of metronidazole allergy is more common than the current literature suggests.

Immediate rhinoconjunctivitis induced by metamizole and metronidazole

OBJECTIVE

To report a case of immediate rhinoconjunctivitis induced by both metamizole and metronidazole.

METHODS

Skin-tests (prick and intradermal) were performed with metamizole, metronidazole, and espyramicine. Standard RAST was carried out with metamizole and metronidazole. Oral challenge tests were performed single blind with Rhodogil, metronidazole, espyramicine, metamizole, aspirin, and propyfenazone.

RESULTS

Both skin tests and RAST were negative. We also found that the patient tolerated therapeutic doses of espyramicine, aspirin, and propyfenazone. Challenges with Rhodogil, metamizole, and metronidazole elicited immediate rhinoconjunctivitis.

CONCLUSION

This is an exceptional case of immediate rhinoconjunctivitis induced by two unrelated drugs (metamizole and metronidazole). The pathogenic mechanism implicated in this process remains unclear. Inhibition of the cyclooxygenase pathway was excluded and we could not demonstrate the presence of specific IgE antibodies. Nevertheless, an immunologic or idiosyncratic mechanism could be responsible.

Mechanisms of drug reactions: the metabolic track

Hypersensitivity syndrome (HSR) describes a drug-induced symptom complex consisting of fever, rash, and internal organ involvement. Although these reactions are rare, they are very important because of their severity and unpredictability. The metabolic conversion of drugs to chemically-reactive products is now established as a prerequisite for many idiosyncratic drug reactions. In the setting of HSR, an imbalance in the rates of formation of reactive metabolites and of enzymatic detoxification can lead to accumulation of these byproducts. Reactive metabolites could act as haptens eliciting an immune response, covalently bind target proteins causing cell death, or interact with nucleic acids leading to mutations. The lymphocyte toxicity assay (LTA) provides an in vitro assessment of host susceptibility to reactive metabolites of a given drug. It has validated the clinical finding of increased risk of HSR in first degree relatives of patients. It is hoped that the LTA will be used to predict host susceptibility before drug exposure. Ultimately it is hoped that the genetic defects that lead to drug reactions will be identified. This would improve drug development safety and allow primary prevention of serious reactions.