Clinical Update on the Use of Moxifloxacin in the Treatment of Community-Acquired Complicated Intraabdominal Infections

Moxifloxacin promotes two-photon microscopic imaging for discriminating different stages of DSS-induced colitis on mice

BACKGROUND

Accurate diagnosis of patients with ulcerative colitis (UC) can reduce their risk of developing colorectal cancer. This study intended to explore whether moxifloxacin, an agent with fluorescence potential, could promote two-photon microscopy (TPM) diagnosis for mice with dextran sodium sulfate (DSS)-induced colitis, which could imitate human UC.

METHODS

32 Balb/c mice were randomly divided into 4 groups: control, acute colitis, remission colitis and chronic colitis. Fluorescence parameters, imaging performance, and tissue features of different mouse models were compared under moxifloxacin-assisted TPM and label-free TPM.

RESULTS

Excitation wavelength of 720 nm and moxifloxacin labeling time of 2 min was optimal for moxifloxacin-assisted TPM. With moxifloxacin labeling for colonic tissues, excitation power was decreased to 1/10 of that without labeling while fluorescence intensity was increased to 10-fold of that without labeling. Photobleaching was negligible after moxifloxacin labeling and moxifloxacin fluorescence kept stable within 2 h. Compared with the control group, moxifloxacin fluorescence was reduced in the three colitis groups (P < 0.05). Meanwhile, the proportion of enhanced moxifloxacin fluorescence regions was (22.4 ± 1.6)%, (7.7 ± 1.0)%, (13.5 ± 1.7)% and (5.0 ± 1.3)% in the control, acute, remission and chronic groups respectively, with significant reduction in the three colitis groups (P < 0.05). Besides, variant tissue features of experimental colitis models were presented under moxifloxacin-assisted TPM, such as crypt opening, glandular structure, adjacent glandular space and moxifloxacin distribution.

CONCLUSIONS

With unique biological interaction between moxifloxacin and colonic mucosa, moxifloxacin-assisted TPM imaging is feasible and effective for accurate diagnosis of different stages of experimental colitis.

Photodegradation of Moxifloxacin Hydrochloride Solutions under Visible Light Irradiation: Identification of Products and the Effect of pH on their Formation

The photodegradation study is essential for the phototoxicity assessment of fluoroquinolones. Various LC-MS techniques and ultraviolet (UV) lamp irradiation conditions have been used for the identification of their photodegradation products. In this study, visible light (400-760 nm) lamp irradiation was selected for the photodegradation of moxifloxacin (MOXI) hydrochloride solutions. Two photodegradation products were identified by LC-MS/MS at first, but one product could not be speculated from the mass spectrum and any known degradation mechanisms. To obtain an adequate amount for the structure elucidation, this unknown product was isolated by recrystallization and semi-preparative HPLC. Then, its structure was further identified by ¹H-NMR, ¹³C-NMR, and 2D-NMR. Based on spectral data, this new photodegradation product was unambiguously named as 7-[3-(3-aminopropyl)-1H-pyrrol-1-yl]-1-cyclopropyl-6-fluoro-8-methoxy-4-oxo-1,4-dihydroquinoline-3-carboxylic acid, which was formed through the open of hexahydroxy N-containing heterocycle and the formation of two alkene bonds in pyrrole ring. The effects of solution pH value on the formation of photodegradation products were compared. Their production was minimum at pH 5.0 and maximum at pH 7.0. Because MOXI hydrochloride has been used extensively in clinical practice and visible light is the most possible light source that pharmaceutical products are exposed to, our study is important for the quality control of MOXI liquid preparations.

Complicated Intra-Abdominal Infections: The Old Antimicrobials and the New Players

Complicated intra-abdominal infections (cIAIs) are an important cause of morbidity and mortality worldwide. They are diagnosed when the initial abdominal organ infection has spread into the peritoneal space. Successful treatment relies on adequate source control and appropriate empiric antimicrobial therapy. Inappropriate antimicrobial therapy may result in poor patient outcomes and increases in healthcare costs. Current guidelines recommend several single and combination antimicrobial regimens; however, empiric antimicrobial treatment has been complicated by the increasing rates of resistant organisms, especially the extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae. Additionally, the overuse of carbapenems to combat these resistant pathogens has contributed to the rise of carbapenemase-producing microorganisms, especially Klebsiella pneumoniae. This increasing resistance has prompted the development of novel antimicrobials like ceftazidime-avibactam and ceftolozane-tazobactam, whose activity extends to ESBL-producing microorganisms. Furthermore, the optimal duration of antimicrobial therapy is still unknown, and further research is necessary to find a definitive answer. This review will focus on antimicrobial therapies recommended by the current guidelines, the individual properties of these agents, appropriate duration of therapy, recent clinical trials, and place in therapy of the antimicrobial agents recently approved for the treatment of cIAIs.

Moxifloxacin monotherapy for treatment of complicated intra-abdominal infections: a meta-analysis of randomised controlled trials

To evaluate the efficacy and safety of moxifloxacin monotherapy for treatment of complicated intra-abdominal infections. PubMed, EMBASE, Science Direct, ClinicalTrials.gov and Cochrane Central Register of Controlled Trials were searched to retrieve randomised controlled trials (RCTs) compared moxifloxacin monotherapy with other antibiotics in the treatment of complicated intra-abdominal infections from January 1999 to July 2011. A meta-analysis of all included randomised controlled trials was performed. Four randomised controlled trials including a total of 2444 patients with complicated intra-abdominal infections were included for meta-analysis. The results of the meta-analysis indicated that the moxifloxacin was associated with similar clinical cure rate (four RCTs, 1934 patients, OR = 0.80, 95% CI: 0.61, 1.04, p = 0.09), bacteriological success rates (four RCTs, 1484 patients, OR = 0.79, 95% CI: 0.59, 1.05, p = 0.11) and mortality (four RCTs, 2227 patients, OR = 0.91, 95% CI: 0.45, 1.83, p = 0.79) compared with the control group. The overall incidence of adverse events of moxifloxacin was significantly higher than that in the control group (three RCTs, 1367 patients, OR = 1.33, 95% CI: 1.07, 1.63, p = 0.008), although the incidence of drug-related adverse events (three RCTs, 1601 patients, OR = 1.13, 95% CI: 0.69, 1.85, p = 0.63) and serious adverse events (three RCTs, 1815 patients, OR = 1.23, 95% CI: 0.59, 2.60, p = 0.58) were similar between the compared treatment groups. Moxifloxacin is an effective and relatively safe option for the treatment of patients with intra-abdominal infections. Moxifloxacin monotherapy has similar efficacy to combination therapy.