Treatment of the Fluoroquinolone-Associated Disability: The Pathobiochemical Implications

Fluoroquinolone-Induced Multisystem Toxicity: A Case Report

Fluoroquinolones are widely prescribed antibiotics with well-known, mostly transient adverse effects, the most common of which are gastrointestinal disturbances, headaches, dizziness, rash, etc. However, a less recognized yet profoundly debilitating complication exists known as fluoroquinolone-associated disability (FQAD), operationally defined as impacting at least two systems (neurological, musculoskeletal, psychiatric, and/or cardiovascular) for at least 30 days post-cessation of a fluoroquinolone and with an outcome reported as disability. Unfortunately, this syndrome has yet to be formally recognized by the medical community. As such, FQAD patients are rarely diagnosed and undergo extensive diagnostic testing, leading to unnecessary costs to the patient and our healthcare system. Herein, we present the case of a 41-year-old male patient who developed acute bilateral numbness and tingling in his upper and lower extremities after just two doses of ciprofloxacin for epididymitis. Despite extensive evaluations from various specialists and therapists over the following 18 months, his symptoms continued to progress without any clear insight into the cause of his symptoms. He eventually reached out to an FQAD specialist due to his own suspicions and began therapy with hyperbaric oxygen, IV magnesium, and IV glutathione. Mild improvement was noted from these therapies, but he was unable to undergo regular treatments due to the financial debt acquired from his extensive medical workups and ultimately stopped treatment completely without any further improvements. Our case report highlights the importance of early recognition of FQAD to start prompt treatment and avoid costly testing. Overall, we aim to raise awareness of FQAD among clinicians as a potential complication of fluoroquinolone use.

Antimicrobial Resistance and Sports: The Scope of the Problem, Implications for Athletes' Health and Avenues for Collaborative Public Health Action

Antimicrobial resistance (AMR) poses a global threat, leading to increased mortality and necessitating urgent action-however, its impact on athletes and the world of sports has hitherto been neglected. Sports environments (including athletic and aquatic) exhibit high levels of microbial contamination, potentially contributing to the spread of resistant microorganisms during physical activities. Moreover, the literature suggests that travel for sports events may lead to changes in athletes' gut microbiomes and potentially impact their antibiotic resistance profiles, raising questions about the broader implications for individual and public/global health. The prevalence of Staphylococcus aureus (S. aureus) among athletes (particularly those engaged in contact or collision sports) ranges between 22.4% and 68.6%, with MRSA strains being isolated in up to 34.9% of tested individuals. Factors such as training frequency, equipment sharing, delayed post-training showers, and a history of certain medical conditions are linked to higher colonization rates. Moreover, MRSA outbreaks have been documented in sports teams previously, highlighting the importance of implementing preventive measures and hygiene protocols in athletic settings. In light of the growing threat of AMR, there is a critical need for evidence-based treatment guidelines tailored to athletes' unique physiological demands to ensure responsible antibiotic use and mitigate potential health risks. While various initiatives-such as incorporating AMR awareness into major sporting events-aim to leverage the broad audience of sports to communicate the importance of addressing AMR, proactive measures (including improved AMR surveillance during large sporting events) will be indispensable for enhancing preparedness and safeguarding both athletes' and the general public's health. This narrative review thoroughly assesses the existing literature on AMR and antibiotic usage in the context of sports, aiming to illuminate areas where information may be lacking and underscoring the significance of promoting global awareness about AMR through sports.

Lactoferricin B Combined with Antibiotics Exhibits Leukemic Selectivity and Antimicrobial Activity

The fusion of penetrating peptides (PPs), e.g., cell penetration peptides (CPPs) or antimicrobial peptides (AMPs), together with antimicrobial agents is an expanding research field. Specific AMPs, such as lactoferricin B (LfcinB), have demonstrated strong antibacterial, antifungal, and antiparasitic activity, as well as valuable anticancer activity, proving beneficial in the development of anticancer conjugates. The resulting conjugates offer potential dual functionality, acting as both an anticancer and an antimicrobial agent. This is especially necessary in cancer treatment, where microbial infections pose a critical risk. Leukemic cells frequently exhibit altered outer lipid membranes compared to healthy cells, making them more sensitive to compounds that interfere with their membrane. In this study, we revisited and reanalyzed our earlier research on LfcinB and its conjugates. Furthermore, we carried out new experiments with a specific focus on cell proliferation, changes in membrane asymmetric phosphatidylserine location, intracellular reactive oxygen species (ROS) generation, mitochondrial functions, and in vitro bacterial topoisomerase inhibition.

Fluoroquinolones: Neurological Complications and Side Effects in Clinical Practice

Fluoroquinolones, a popular antibiotic class that inhibits nucleic acid synthesis of bacteria by disrupting the activity of the enzyme's topoisomerase IV and DNA gyrase, are used to treat bacterial infections. However, the widespread use of these drugs has allowed for the development of microbial resistance in recent years. Quinolones also have many clinically relevant side effects, including psychosis, confusion, seizures, headaches, dizziness, and nausea. Common side effects include tendinitis, myopathy, depression, and fatigue. Cardiovascular side effects include increased risk of aortic aneurysm, aortic dissection, and QT interval prolongation. Overall, quinolones can be an effective choice for treating bacterial infections. Still, the side effect profile and decreased efficacy secondary to microbial resistance no longer make the quinolone class an ideal choice for many types of infection. A better understanding of the role of quinolone-mediated or neurological damage, cardiovascular impairment, and musculoskeletal involvement is imperative to determine the risks/benefits for the clinician.

Antibiotic exposure is associated with decreased risk of psychiatric disorders

Objective: This study sought to investigate the relationship between antibiotic exposure and subsequent risk of psychiatric disorders. Methods: This retrospective cohort study used a national database of 69 million patients from 54 large healthcare organizations. We identified a cohort of 20,214 (42.5% male; 57.9 ± 15.1 years old [mean ± SD]) adults without prior neuropsychiatric diagnoses who received antibiotics during hospitalization. Matched controls included 41,555 (39.6% male; 57.3 ± 15.5 years old) hospitalized adults without antibiotic exposure. The two cohorts were balanced for potential confounders, including demographics and variables with potential to affect: the microbiome, mental health, medical comorbidity, and overall health status. Data were stratified by age and by sex, and outcome measures were assessed starting 6 months after hospital discharge. Results: Antibiotic exposure was consistently associated with a significant decrease in the risk of novel mood disorders and anxiety and stressor-related disorders in: men (mood (OR 0.84, 95% CI 0.77, 0.91), anxiety (OR 0.88, 95% CI 0.82, 0.95), women (mood (OR 0.94, 95% CI 0.89,1.00), anxiety (OR 0.93, 95% CI 0.88, 0.98), those who are 26-49 years old (mood (OR 0.87, 95% CI 0.80, 0.94), anxiety (OR 0.90, 95% CI 0.84, 0.97)), and in those ≥50 years old (mood (OR 0.91, 95% CI 0.86, 0.97), anxiety (OR 0.92, 95% CI 0.87, 0.97). Risk of intentional harm and suicidality was decreased in men (OR 0.73, 95% CI 0.55, 0.98) and in those ≥50 years old (OR 0.67, 95% CI 0.49, 0.92). Risk of psychotic disorders was also decreased in subjects ≥50 years old (OR 0.83, 95 CI: 0.69, 0.99). Conclusion: Use of antibiotics in the inpatient setting is associated with protective effects against multiple psychiatric outcomes in an age- and sex-dependent manner.

Mechanistic Approach of Effective Combination of Antibiotics Against Clinical Bacterial Strains Having New Delhi Metallo-Beta-Lactamase Variants and Functional Gain Laboratory Mutant

Antimicrobial resistance has emerged as a serious issue for physicians and health-care workers treating infections that could lead to the next pandemic. One of the key resistance mechanisms is beta-lactamases. Although several beta-lactamase inhibitors in combination with antibiotics have been created and are being utilized in clinical settings, resistance to these formulations has also been evolving in the bacterial population due to their distinct targets. In this study we used effective combination of antibiotic as an approach to inhibit multidrug resistance bacteria. We used four combinations and checked its efficacy against NDM (New Delhi Metallo-beta-lactamase) variants and functional gain laboratory mutant by employing FICI, enzyme kinetics, fluorescence and computational biology approaches (Docking and Molecular Dynamics Simulation). FICI values of all the combinations were either less than 0.5 or equal to 0.5. Binding features acquired by spectroscopic techniques showed important interaction and complex formation between drugs and enzymes with decreased ksv and kq values. In steady-state kinetics, a reduction in hydrolytic efficiency of enzymes was shown by cooperative binding behaviour when they were treated with different drugs. We have also tested functional gain laboratory mutant developed in our lab, keeping in view that if in future upcoming variants of this kind be emerged then these mutants could also be subsided by combinational therapy. This study identifies three other combinations better than fluoroquinolones effective against NDM variants and laboratory mutant.

Fluoroquinolone-Associated Movement Disorder: A Literature Review

BACKGROUND

Fluoroquinolones (FQNs) are related to several central nervous system side effects. This review aims to evaluate the clinical-epidemiological profile, pathophysiological mechanisms, and management of FQNs-associated movement disorders (MDs).

METHODS

Two reviewers identified and assessed relevant reports in six databases without language restriction between 1988 and 2022.

RESULTS

A total of 45 reports containing 51 cases who developed MDs secondary to FQNs were reported. The MDs included 25 myoclonus, 13 dyskinesias, 7 dystonias, 2 cerebellar syndromes, 1 ataxia, 1 tic, and 2 undefined cases. The FQNs reported were ciprofloxacin, ofloxacin, gatifloxacin, moxifloxacin, levofloxacin, gemifloxacin, and pefloxacin. The mean and median age were 64.54 (SD: 15.45) and 67 years (range: 25-87 years). The predominant sex was male (54.16%). The mean and median time of MD onset were 6.02 (SD: 10.87) and 3 days (range: 1-68 days). The mean and median recovery time after MD treatment was 5.71 (SD: 9.01) and 3 days (range: 1-56 days). A complete recovery was achieved within one week of drug withdrawal in 80.95% of the patients. Overall, 95.83% of the individuals fully recovered after management.

CONCLUSIONS

Future cases need to describe the long-term follow-up of the individuals. Additionally, FQN-induced myoclonus should include electrodiagnostic studies.

Overview of Side-Effects of Antibacterial Fluoroquinolones: New Drugs versus Old Drugs, a Step Forward in the Safety Profile?

Antibacterial fluoroquinolones (FQs) are frequently used in treating infections. However, the value of FQs is debatable due to their association with severe adverse effects (AEs). The Food and Drug Administration (FDA) issued safety warnings concerning their side-effects in 2008, followed by the European Medicine Agency (EMA) and regulatory authorities from other countries. Severe AEs associated with some FQs have been reported, leading to their withdrawal from the market. New systemic FQs have been recently approved. The FDA and EMA approved delafloxacin. Additionally, lascufloxacin, levonadifloxacin, nemonoxacin, sitafloxacin, and zabofloxacin were approved in their origin countries. The relevant AEs of FQs and their mechanisms of occurrence have been approached. New systemic FQs present potent antibacterial activity against many resistant bacteria (including resistance to FQs). Generally, in clinical studies, the new FQs were well-tolerated with mild or moderate AEs. All the new FQs approved in the origin countries require more clinical studies to meet FDA or EMA requirements. Post-marketing surveillance will confirm or infirm the known safety profile of these new antibacterial drugs. The main AEs of the FQs class were addressed, highlighting the existing data for the recently approved ones. In addition, the general management of AEs when they occur and the rational use and caution of modern FQs were outlined.

Quinolone Ear Drops and Achilles Tendon Rupture

BACKGROUND

Delayed eardrum healing has been observed in the ear opposite to the ear treated with otic quinolones (OQ) in rats. Case reports describe tendinopathies after OQ treatment, suggesting adverse systemic effects.

METHODS

We studied patients aged 19 to 64 years with diagnosis of otitis externa or media in private insurance between 2005 and 2015. We compared OQ treatment against otic neomycin, oral amoxicillin, or azithromycin. Outcomes included Achilles tendon rupture (ATR), Achilles tendinitis (AT), and all-type tendon rupture (ATTR). We applied an active comparator, new-user design with 1-year look-back and ceased follow-up at initiation of systemic steroids or oral quinolones, external injury, hospitalization, and after 35 days. We used trimmed stabilized inverse probability of treatment weights to balance comparison groups in a survival framework. Negative outcomes (clavicle fractures or sports injuries) were examined to rule out differences from varied physical activity (unmeasured confounding).

RESULTS

We examined 1 501 009 treated otitis episodes. Hazard ratios (HR) for OQ exposure associated with ATR were 4.49 (95% confidence interval [CI], 1.83-11.02), AT 1.04 (95% CI, 0.73-1.50), and ATTR 1.71 (95% CI, 1.21-2.41). Weighted risk differences (RD) per 100 000 episodes for OQ exposure were ATR 7.80 (95% CI, 0.72-14.89), AT 1.01 (95% CI, -12.80 to 14.81), and ATTR 18.57 (95% CI, 3.60-33.53). Corresponding HRs for clavicle fractures and sports injuries were HR,1.71 (95% CI, 0.55-5.27) and HR,1.45 (95% CI, 0.64-3.30), suggesting limited residual confounding.

CONCLUSIONS

OQ exposure may lead to systemic consequences. Clinicians should consider this potential risk and counsel patients accordingly. Risk factors and mechanisms for this rare, adverse effect deserve further evaluation. Mechanistic and other clinical studies are warranted to corroborate this finding.

Direct electrochemical determination of environmentally harmful pharmaceutical ciprofloxacin in 3D printed flow-through cell

Rising amounts of antibiotic residues in wastewater cause serious problems including increased bacterial resistance. Wastewater treatment plants (WWTPs) do not, in the case of new, modern pharmaceuticals, ensure their complete removal. Ciprofloxacin (CIP) is one of many micropollutants that partially pass through WWTPs, implying that its monitoring is essential for the assessment of the water quality. In real sewage systems, the determination of CIP needs to be performed under flowing conditions, which calls for the deployment of inexpensive, robust, and easily integrable approaches such as electrochemical techniques. However, to the best of our knowledge, there is no report on the electrochemical determination of CIP in a flowing matrix. To bridge this gap, we perform here cyclic and square-wave voltammetric sensing study of CIP employing boron-doped diamond screen printed electrodes in a custom-made 3D printed flow-through cell to mimic conditions in real sewage systems. An irreversible two-step oxidation of CIP is demonstrated, with the first step providing clear Faradaic response as analytically relevant signal. This response was found to scale with the sample flow rate according to the prediction given by Levich equation. Our work provides an in-depth inspection of the electrochemical response of CIP under controlled-convection conditions, which is an essential prerequisite for monitoring this antibiotic in real flowing sewage systems.

Complexation of fluoroquinolones with magnesium ions

Aim. To evaluate strength of magnesium ion complexes with levofloxacin and moxifloxacin.

Materials and methods. Complexation of levofloxacin, moxifloxacin, and reference ligands (ethylenediaminetetraacetate (EDTA), sodium citrate, and glycine) with magnesium ions in the range from 0.0 to 1.0 mmol / l was studied. The technique developed by the authors (patent RU 2680519 C1) was used to measure the rate of a model formation reaction of a magnesium phosphate coarse dispersion. Complexing activity of ligands was expressed in relation to EDTA activity and compared with the theoretical ion exchange equilibrium constants. The half maximal effective concentration (C50) calculated by the Michaelis − Menten equation was used to evaluate the dependence of the complexing activity on the dose.

Results. A correlation between the activity of EDTA, citrate ions, and glycine and the theoretical equilibrium constants (R = −0.87, p < 0.001) was found. In the range from 0.0 to 0.4 mmol / l, both levofloxacin and moxifloxacin showed a lesser complexing effect than EDTA (p < 0.001), and in the range from 0.6 to 1.0 mmol / l, their complexing effect was comparable (p > 0.050). The activity of fluoroquinolones did not differ at any concentration (p > 0.050), but moxifloxacin C50 (0.13 mmol / l; 95% confidence interval (CI) 0.11–0.15) was significantly lower than that of levofloxacin (0.22 mmol / l; 95% CI 0.19–0.26), (p < 0.001). Within the 0.4–1.0 mmol / l concentration range, the activity of levofloxacin was higher than that of citrate ions and glycine (p < 0.001). Complexing activity of moxifloxacin was higher than that of citrate ions within the range of 0.2–1.0 mmol / l, and in the range of 0.4–1.0 mmol / l, it was higher than that of glycine (p < 0.001).

Conclusion. The proposed method showed that the complexing activity of fluoroquinolones was close to that of EDTA and exceeded the activity of citrate ions and glycine. The complexation of fluoroquinolones may be associated with their ability to induce side effects associated with magnesium deficiency.

Photocatalytic degradation of lomefloxacin antibiotics using hydrothermally synthesized magnesium titanate under visible light-driven energy sources

Antibiotics in water system pose a human health risk due to the rise of antibacterial activity in the environmental web. Advanced oxidation processes are the potential to become an effective treatment technology for targeting antibiotics. This study demonstrates the visible light photocatalysis of lomefloxacin using magnesium titanate (MgTiO₃). The nanomaterial was subjected to computational analysis to study morphology, functional, and optical characteristics through FESEM, XRD, FTIR, BET, UV-Vis, etc. Importantly, MgTiO₃ had band gap energy of 3.09 eV. The photocatalytic studies were performed to observe different parameters affecting lomefloxacin degradation such as initial concentration, catalyst dosage, and pH. The nanomaterial exhibited the maximum lomefloxacin degradation. The study revealed that 30 mg/L of catalyst was optimum to degrade 10 mg/L of lomefloxacin with 30-W LED irradiation up to 150 min. Reactive species, namely, electron, hole, hydroxyl, and superoxide radicals, comprised the primary photocatalytic mechanism for lomefloxacin degradation. Ultimately, the summative result from this study highlights the suitability of the photocatalytic system to treat persistent antibiotics in aqueous environment.

Antibiotic Therapy and Athletes: Is the Mitochondrial Dysfunction the Real Achilles’ Heel?

It is widely recognized that athletes consume oral antibiotics almost twice as often as observed in the non-sports population in order to reduce as much as possible the period of inactivity due to bacterial diseases. However, increasing evidences have demonstrated the ability of some classes of antibiotics to induce muscle weakness, pain, and a feeling of fatigue upon resuming physical activity conditions that considerably limit the athletic performance of athletes, ascribable to alterations in the biochemical mechanisms underlying normal musculoskeletal activity, such as mitochondrial respiration. For this reason, tailoring a treatment plan for effective antibiotics that limit an athlete’s risk is paramount to their safety and ability to maintain adequate athletic performance. The present review illustrates and critically analyzes the evidence on the use of antibiotics in sports, deepening the molecular mechanisms underlying the onset and development of muscle–tendon alterations in athletes as well as delineating the pharmacological strategies aimed at counteracting such adverse events.

The impact of oral ciprofloxacin on the structure and functions of rat gastric mucosa

Ciprofloxacin (CPX), is a fluoroquinolone antibiotic used to treat a number of gram-negative and gram-positive bacterial infections. Ciprofloxacin can cause severe side effects, ranging from tendon problems, nerve damage, to serious mood or behavior changes.

The purpose of this study was to investigate how ciprofloxacin affects gastric cell lines in rats with a distinctive emphasis on physiological, histopathological, and bacteriological changes. Male albino rats (n = 21) were distributed into three groups; control, CPX, and CPX-withdrawal groups. The treated rats were given CPX tablets (12.5 mg/kg) dissolved in carboxymethyl cellulose (CMC) 0.5% orally once daily via gavage for sixty consecutive days. Control rats received only the vehicle. The withdrawal group was treated for 60 days and the drug was withdrawn for another sixty days. After completion of the experiment, all rats were sacrificed and gastric tissues were treated for light, immunohistochemical, and scanning electron microscopic examination. Image J software was used to measure immune-labeled gastric epithelial cells. Blood samples were also collected for H. Pylori immunoglobulins IgM, IgA, and IgG. Results showed that treated rats acquired significantly strongly positive tumor necrosis factor (TNFα) and significant reduction of serum level of H. pylori IgM, IgA, and IgG in all the study groups. It could be concluded that prolonged oral CPX administration to albino rats changes the gastric mucosal architecture and bacteriology.

Does oral ciprofloxacin affect the structure of thoracic aorta in adult and senile male albino rats? A clue to fluoroquinolones-induced risk of aortic dissection

In this study, the effect of oral ciprofloxacin on the structure of the thoracic aorta in rats was investigated. Twenty four male albino rats were divided into 4 groups (6 rats/group): group I (adult control), group II (adult rats treated with ciprofloxacin), group III (senile control), and group IV (senile rats treated with ciprofloxacin). Rats in groups II and IV received ciprofloxacin via oral gavage in a daily dose of 3.5 mg/kg/d for 14 days, while control rats received equivalent amount of distilled water used to dissolve the drug. After 2 weeks, all rats were sacrificed, thoracic aortae were dissected, and half of the specimens were processed for paraffin sections and examined by light microscopy. The other half of the specimens were prepared for scanning electron microscopy. Sections from rats treated with ciprofloxacin showed evident damaging effect on aortic wall particularly in (group IV). Aortic intima showed, focal desquamation of the lining epithelium. Tunica media exhibited loss of the normal concentric arrangement and degeneration of the smooth muscle cells. Immune staining for alpha smooth muscle actin showed muscle damage. Interestingly, some sections in (group IV) showed out-pouch (aneurysm like) of the aortic wall. There was dense collagen fibers deposition. Scanning electron microscopic observations of (group IV) revealed uneven intima, adherent blood cells and fibrin filaments to damaged intima, and out-pouch formation. It was concluded that oral ciprofloxacin caused deleterious structural changes in the thoracic aortic wall of rats explaining clinical observations of fluoroquinolones induced risk of aortic dissection and aneurysm.

A New Criterion for Fluoroquinolone-Associated Disability Diagnosis: Functional Gastrointestinal Disorders

Background and Objectives: Fluoroquinolones (FQs) are a broad-spectrum class of antibiotics routinely prescribed for common bacterial infections despite recent recommendations to use them only for life-threatening cases. In addition to their antimicrobial properties, FQs act in the central nervous system as GABAA receptor inhibitors, which could potentially affect functionality of the vagus nerve at the forefront of gastrointestinal (GI) tract function. Alterations in neural control of digestion have been shown to be linked to Functional Gastrointestinal Disorders (FGIDs), which are usually diagnosed based on self-reported symptoms. The aim of this study was to assess the incidence of FGIDs following FQ use. Materials and Methods: Self-reports from the FDA Adverse Event Reporting System were analyzed together with ~300 survey responses from a social network derived sample to the Bowel Disease Questionnaire. Results: The results of this study suggested that six different FQs are associated with a wide range of GI symptoms not currently reported in the drugs’ labels. The responses from the survey suggested that ~70% of FQ users scored positive for FGID, with no positive correlation between drug type, duration of administration, dosage and frequency of administration. Conclusions: This study showed that GI disorders other than nausea, vomiting and diarrhea are more common than currently reported on the drug labels, and that FGIDs are possibly a common consequence of FQ use even after single use.

Between Curing and Torturing: Burden of Adverse Reaction in Drug-Resistant Tuberculosis Therapy

Drug-resistant tuberculosis (DR-TB) requires prolonged and complex therapy which is associated with several adverse drug reactions (ADR). The burden of ADR can affect the quality of life (QoL) of patients that consists of physical, mental, and social well-being, and influences the beliefs and behaviors of patient related to treatment. This article reviews the burden of ADR and its association with QoL and adherence. We used PubMed to retrieve the relevant original research articles written in English from 2011 to 2021. We combined the following keywords: "tuberculosis," "Drug-resistant tuberculosis," "Side Effect," "Adverse Drug Reactions," "Adverse Event," "Quality of Life," "Adherence," "Non-adherence," "Default," and "Loss to follow-up." Article selection process was unsystematic. We included 12 relevant main articles and summarized into two main topics, namely, 1) ADR and QoL (3 articles), and 2) ADR and therapy adherence (9 articles). The result showed that patients with ADR tend to have low QoL, even in the end of treatment. Although it was torturing, the presence of ADR does not always result in non-adherence. It is probably because the perception about the benefit of the treatment dominates the perceived barrier. In conclusion, burden of ADR generally tends to degrade QoL of patients and potentially influence the adherence. A comprehensive support from family, community, and healthcare provider is required to help patients in coping with the burden of ADR. Nevertheless, the regimen safety and efficacy improvement are highly needed.

Fluoroquinolones: Blessings Or Curses

Fluoroquinolones are one of the world's most valuable and popularly used categories of antimicrobial agents. This paper attempts to review the substantial progress of fluoroquinolones from their discovery to black box warning. Antibiotic drug choice will remain difficult in the presence of increasing resistance, but the introduction of fluoroquinolones has created a new and exciting era in antimicrobial treatment. These are a synthetic heterogeneous group of compounds used in both hospital and community practices to treat numerous severe infections. The era of quinolone antibiotics began with the serendipitous discovery of the quinolone prototype in 1962. The chronological development of fluoroquinolone reported that nalidixic acid was the first quinolone that gained popular choice for the treatment of urinary tract infection. The subsequent agents like levofloxacin, ofloxacin, norfloxacin, gatifloxacin, moxifloxacin, clinafloxacin, sparfloxacin, and ciprofloxacin were derived through side chain and nuclear manipulation from basic pharmacophore. The fluoroquinolone motifs have been found as a milestone, effective in certain infections that are respiratory tract infection, urinary tract infection, bone disorders, meningococcal and mycobacterial infections, sexually transmitted diseases, skin infections, etc. Fluoroquinolones are first entirely man-made antibiotics that exhibit antibacterial activity through the inhibition of topoisomerase II, topoisomerase IV and deoxyribonucleic acid gyrase, which is vital for chromosome replication and function. The post-marketing surveillance pointed out the favorable side effects associated with fluoroquinolones such as phototoxicity, QT interval prolongation and anaphylaxis. The discovery, development and clinical use of fluoroquinolone antibiotics in the last century contributed to a decline in morbidity and mortality rates.

Structural Characterization of the Millennial Antibacterial (Fluoro)Quinolones-Shaping the Fifth Generation

The evolution of the class of antibacterial quinolones includes the introduction in therapy of highly successful compounds. Although many representatives were withdrawn due to severe adverse reactions, a few representatives have proven their therapeutical value over time. The classification of antibacterial quinolones into generations is a valuable tool for physicians, pharmacists, and researchers. In addition, the transition from one generation to another has brought new representatives with improved properties. In the last two decades, several representatives of antibacterial quinolones received approval for therapy. This review sets out to chronologically outline the group of approved antibacterial quinolones since 2000. Special attention is given to eight representatives: besifloxacin, delafoxacin, finafloxacin, lascufloxacin, nadifloxacin and levonadifloxacin, nemonoxacin, and zabofloxacin. These compounds have been characterized regarding physicochemical properties, formulations, antibacterial activity spectrum and advantageous structural characteristics related to antibacterial efficiency. At present these new compounds (with the exception of nadifloxacin) are reported differently, most often in the fourth generation and less frequently in a new generation (the fifth). Although these new compounds' mechanism does not contain essential new elements, the question of shaping a new generation (the fifth) arises, based on higher potency and broad spectrum of activity, including resistant bacterial strains. The functional groups that ensured the biological activity, good pharmacokinetic properties and a safety profile were highlighted. In addition, these new representatives have a low risk of determining bacterial resistance. Several positive aspects are added to the fourth fluoroquinolones generation, characteristics that can be the basis of the fifth generation. Antibacterial quinolones class continues to acquire new compounds with antibacterial potential, among other effects. Numerous derivatives, hybrids or conjugates are currently in various stages of research.

Fluoroquinolones-Associated Disability: It Is Not All in Your Head

Fluoroquinolones (FQs) are a broad class of antibiotics typically prescribed for bacterial infections, including infections for which their use is discouraged. The FDA has proposed the existence of a permanent disability (Fluoroquinolone Associated Disability; FQAD), which is yet to be formally recognized. Previous studies suggest that FQs act as selective GABAA receptor inhibitors, preventing the binding of GABA in the central nervous system. GABA is a key regulator of the vagus nerve, involved in the control of gastrointestinal (GI) function. Indeed, GABA is released from the Nucleus of the Tractus Solitarius (NTS) to the Dorsal Motor Nucleus of the vagus (DMV) to tonically regulate vagal activity. The purpose of this review is to summarize the current knowledge on FQs in the context of the vagus nerve and examine how these drugs could lead to dysregulated signaling to the GI tract. Since there is sufficient evidence to suggest that GABA transmission is hindered by FQs, it is reasonable to postulate that the vagal circuit could be compromised at the NTS-DMV synapse after FQ use, possibly leading to the development of permanent GI disorders in FQAD.

Antibiotic use amongst pregnant women in a public hospital in KwaZulu-Natal

Background

Antibiotics are amongst the more frequently prescribed medicines in pregnant women and the use of antibiotics is increasing. However, with limited studies available in this population, the safe use of antibiotics in pregnancy remains a concern.

Aim

To evaluate the use of antibiotics amongst pregnant women attending a public health care facility. The main objective of this study was to quantify the types of antibiotics used in pregnant women.

Setting

A public hospital classified as a referral hospital located in Durban, KwaZulu-Natal.

Methods

Demographic and treatment information of women were collected retrospectively from January 2019 to July 2019. A total of 184 pregnant patients, who received antibiotic therapy, were included in this study. Descriptive and analytical measures were used to analyse both patient demographics and treatment variables.

Results

A total of 416 antibiotic prescriptions, issued to 184 patients, were reviewed. Penicillins (39.7%), macrolides (13.0%) and combination penicillin- and beta-lactam inhibitors (12.3%) were reported as the most commonly prescribed antibiotics. Rifamycin (2.9%), hydrazides (2.2%) and aminoglycosides (1.9%) were less frequently prescribed. Most antibiotics were prescribed for diseases of the circulatory system (36.1%).

Conclusion

Several classes of antibiotics were used in pregnancy despite the lack of available safety data and clinical evidence. Informing women of the potential side effects and keeping abreast with new information played an important role in the safe, rational and effective use of medicines that contributed to improving maternal health.

Fluoroquinolone Resistance Among Isolates of Mycobacterium tuberculosis in Khyber Pakhtunkhwa, Pakistan

Fluoroquinolones (FQs) are broad-spectrum second-line antimicrobial drugs commonly used in the treatment of tuberculosis (TB). Data on FQ resistance in the Khyber Pakhtunkhwa (KP) province of Pakistan, a high-burden country, are scarce. This study aimed to analyze the resistance to FQs in this specific geographic area. Samples were collected from 25 districts of KP from 2014 to 2019. Data regarding suspected TB patients were collected from their guardians or secondary caregivers. All the samples were subjected to decontamination and digestion processing. Drug susceptibility testing (DST) was performed according to the standard minimum inhibitory concentration for ofloxacin (OFX), levofloxacin (LEV), and moxifloxacin (MOX), taken as 2, 1, and 1 μg/mL, respectively. For the 5,759 clinical samples collected from 25 districts, DST was conducted for a total of 3,158 samples. Out of the total DSTs, the OFX profile was available for 2,983, MOX profile for 2,290, and LEV profile for 544 samples. OFX and LEV resistance was found to be evenly distributed and has remained the same for the past few years, whereas MOX resistance increased from 1% in 2017 to 4% in 2019. Among a total of 807 OFX-resistant isolates, 218 (27%) were observed to be monoresistant to OFX, whereas 589 (73%) isolates were resistant to OFX and at least one other anti-TB drug. Drug resistance to OFX was higher in multidrug-resistant TB (MDR-TB), that is, 428 (53%). It was concluded that resistance to MOX has been increasing, whereas OFX resistance is much higher in MDR cases. FQ resistance needs to be continuously monitored to avoid further side effects. This study provides useful information for better management of FQ resistance with reference to the global TB control program 2030.

Dermatomyositis Developed After Exposure to Epstein-Barr Virus Infection and Antibiotics Use

Dermatomyositis is an inflammatory disorder involving muscle and skin. Similar to many other autoimmune diseases, environmental factors appear to trigger the onset of disease in some cases. Many drugs have been reported to be associated with dermatomyositis, and rarely infections have been described as potential triggering agents. Here we are describing a case of dermatomyositis that developed after doxycycline and levofloxacin use, who also had recent Epstein-Barr virus infection. Dermatomyositis associated with doxycycline or levofloxacin use has not yet been described in the literature, while reports of dermatomyositis after Epstein-Barr virus infection have been rare and limited to juvenile dermatomyositis or in association with cancer. It is important for clinicians to be aware of this rare association so that the diagnosis and treatment can be exercised promptly.

A mechanistic approach to prove the efficacy of combination therapy against New Delhi metallo-β-lactamases producing bacterial strain: a molecular and biochemical approach

BACKGROUND

NDM-1 is a novel broad-spectrum metallo-β-lactamase with the capability to grant resistance to almost all β-lactam antibiotics. Its widespread dissemination made treatment options a major challenge to combat, causing threat to public health worldwide. Due to antibiotic resistance problems, development of effective therapeutics for infections caused by NDM-1 producing strains is urgently required. Since combination therapies are proved to be effective in many cases, this study was initiated to put forward novel effective antibiotics combinations for fighting infections caused by NDM-1 producing strains.

METHODS

Streptomycin and amikacin combination and streptomycin and ciprofloxacin combination were tested by checkerboard assay. NDM-1 protein/enzyme was then expressed and purified to carry out enzyme kinetics study, CD and fluorescence spectroscopic studies.

RESULTS

Streptomycin and amikacin combination and streptomycin and ciprofloxacin combination showed synergistic effect towards NDM-1 producing bacterial strains as shown by FICI results. NDM-1 producing bacterial cells were expressed and purified to obtain protein as the source of enzyme. When NDM-1 enzyme was treated with streptomycin along with amikacin, the efficiency of enzyme was decreased by 49.37% and when the enzyme was treated with streptomycin along with ciprofloxacin, the efficiency of enzyme was decreased by 29.66% as revealed by enzyme kinetic studies. Due to binding of streptomycin and amikacin in combination and streptomycin and ciprofloxacin in combination, conformational changes in the secondary structure of NDM-1 enzyme were observed by CD spectroscopic studies. Antibiotics streptomycin and ciprofloxacin bind with NDM-1 through exothermic processes, whereas amikacin binds through an endothermic process. All three antibiotics bind spontaneously with an association constant of the order of 104 M-1 as revealed by fluorescence spectroscopic studies.

CONCLUSIONS

The therapeutic combination of streptomycin with amikacin and ciprofloxacin plays an important role in inhibiting NDM-1 producing bacterial strains. Therefore, these combinations can be used as effective future therapeutic candidates against NDM-1 producing bacterial cells.

Relationship between fluoroquinolones and the risk of aortic diseases: a meta-analysis of observational studies

Background

Our aim was to determine the relationship between the use of fluoroquinolones and the risk of aortic diseases.

Methods

PubMed, EMBASE and the Web of Science were searched from inception to July 6, 2019, to identify observational studies that evaluated the risk of aortic diseases associated in users of fluoroquinolones compared with nonusers or users of other antibiotics. The primary outcome was the first occurrence of aortic diseases. We used the GRADE approach to rate the strength of evidence. We used the inverse variance method random-effect model to estimate the odds ratios (ORs) with 95% CIs, and statistical heterogeneity was assessed by the I² statistic.

Results

This meta-analysis enrolled 2,829,385 patients reported the relationship between fluoroquinolones and the risk of aortic diseases. Compared with nonusers or users of other antibiotics, users of fluoroquinolone had a significantly increased risk of aortic diseases (adjusted OR, 2.10; 95% CI, 1.65–2.68; P = .000, I² = 16.4%). The quality of evidence was moderate, and the number needed to harm (NNH) for aortic diseases among patients was estimated to be 1301.

Conclusions

The fluoroquinolone use in patients significantly increases the risk of new-onset aortic diseases. Clinicians need to pay attention to these severe adverse events when considering fluoroquinolone use.

Fluoroquinolones and the Risk of Aortic Aneurysm or Aortic Dissection: A Systematic Review and Meta-Analysis

OBJECTIVES

We performed a systematic review and meta-analysis to explore the risk of an aortic aneurysm or aortic dissection following fluoroquinolone administration.

METHODS

PubMed, Cochrane library, ClinicalTrials.gov, Embase and Google Scholar were systematically reviewed for controlled studies including adult patients exposed to fluoroquinolones with a primary outcome of aortic aneurysm or aortic dissection.

RESULTS

The meta-analysis was conducted by pooling the effect estimates of four controlled observational studies (one case-control, one case-crossover and two cohort studies). Fluoroquinolone administration more than doubled the risk to develop aortic aneurysm or aortic dissection within 60 days following fluoroquinolone exposure (adjusted Relative Risk [RR] (95% confidence interval [CI]) = 2.14 (1.93 - 2.36); I2 = 15.8%). The quality of the finding was rated as moderate. The risk increase for aortic aneurysm alone was found to be significant (adjusted RR (95% CI) = 2.23 (2.01 - 2.45); I2 = 0%) while the risk increase for aortic dissection alone was not found to be significant (adjusted RR = 1.88 (0.11 - 3.65); I2 = 74%). In subgroup analysis, the risk increase for aortic aneurysm or aortic dissection appeared to be higher in females compared to males (RR = 1.87 (1.24 - 2.51); I2 = 0% versus RR = 1.58 (1.25 - 1.92); I2 = 0%, respectively) and higher in older patients compared to younger patients (RR = 1.72 (1.37 - 2.07); I2 = 0% versus RR = 1.47 (0.91 - 2.04); I2 = 0%, respectively). Subgroup analysis of two studies which measured the duration-response analysis found that as the duration of fluoroquinolone therapy increased from 3 to 14 days to greater than 14 days, there was an increased risk of aortic aneurysm or dissection.

CONCLUSION

The findings of this meta-analysis confirm the positive association between fluoroquinolones and the development of aortic aneurysm or dissection. The data tend to show that this association may be majorly driven by aortic aneurysm. Additionally, some risk factors appear to prevail including prolonged fluoroquinolone treatment and older age.

Antibiotic-Based Conjugates Containing Antimicrobial HLopt2 Peptide: Design, Synthesis, Antimicrobial and Cytotoxic Activities

Recent studies have shown that modified human lactoferrin 20-31 fragment, named HLopt2, possesses antibacterial and antifungal activity. Thus, we decided to synthesize and evaluate the biological activity of a series of conjugates based on this peptide and one of the antimicrobials with proven antibacterial (ciprofloxacin, CIP, and levofloxacin, LVX) or antifungal (fluconazole, FLC) activity. The drugs were covalently connected to the peptide via amide, methylenecarbonyl moieties, or a disulfide bridge. The antibacterial and antifungal activities were evaluated under Clinical and Laboratory Standard Institute (CLSI) recommended conditions or in a low-salt brain-heart infusion diluted medium (BHI_1/100). Results showed that conjugation of the peptide with the drug increased its antimicrobial activity up to 4-fold. Under CLSI-recommended conditions, all the compounds revealed rather low efficiency. Among conjugates, the highest antibacterial activity was recorded for the CIP-Cys-S-S-HLopt2-NH₂ (III). In BHI_1/100, which had lower differentiating properties, all of the conjugates revealed low MIC and MMC (minimum inhibitory and microbicidal concentrations) values. The disulfide bridge used as a linker in the most active conjugate (III) upon incubation with S. aureus cells is reduced, releasing constituent peptide and CIP-Cys. In addition, we showed that its fluorescently labeled analogue and constituent peptide are able to be internalized into both C. albicans and S. aureus cells. Moreover, the invaluable advantage of the presented conjugates was their low toxicity to mammalian cells and very low hemolytic activity. The current research can form a solid basis for further in vivo studies and drug development.

Synergistic Effects of Anionic/Cationic Dendrimers and Levofloxacin on Antibacterial Activities

Despite the numerous studies on dendrimers for biomedical applications, the antibacterial activity of anionic phosphorus dendrimers has not been explored. In our research, we evaluated the antibacterial activity of modified polycationic and polyanionic dendrimers in combination with levofloxacin (LVFX) against Gram-negative (Escherichia coli ATCC 25922, Proteus hauseri ATCC 15442) and Gram-positive (Staphylococcus aureus ATCC 6538) bacteria. In the case of Gram-negative bacteria, we concluded that a combination of dendrimers and antibiotic gave satisfactory results due to a synergistic effect. The use of fluoroquinolone antibiotics, such as LVFX, not only caused resistance in disease-causing microorganisms but also increased environmental pollution. Therefore, reduction of drug dosage is of general interest.