Intratympanic ciprofloxacin and the human labyrinthine sampling model

Effects of cigarette smoke on Haemophilus influenzae-induced otitis media in a rat model

Exposure to cigarette smoke (CS) is a factor that could delay or worsen the recovery of otitis media (OM) by causing inflammatory swelling of the Eustachian tube (ET). However, despite the suggested relationship, little is known about the association between OM and CS. Therefore, we aimed to evaluate the effects of CS on the development, progression, and recovery of OM, as well as the histological and molecular changes caused by CS exposure, by using a rat model of OM infected with non-typeable Haemophilus influenzae (NTHi). Eighty Sprague-Dawley rats with normal middle ears (MEs) were divided into four groups (n = 20 rats/group): control, CS, OM, and CS + OM. The CS and CS + OM groups were exposed to CS for 2 weeks. The inflammatory reaction to NTHi was more intense and lasted longer in the CS + OM group than in the other groups. Goblet cell proliferation and mucus secretion in the ET were more significant in the CS and CS + OM groups than in the other groups. These findings suggested that because CS directly affects the ET and ME mucosa, bacterial OM can become more severe and may resolve more slowly in the presence of CS exposure rather than in its absence.

Ciprofloxacin 0.3%/dexamethasone 0.1% sterile otic suspension for the topical treatment of ear infections: a review of the literature

The objective of this article is to review the literature related to ciprofloxacin 0.3% and dexamethasone 0.1% sterile otic suspension. A systematic literature search utilizing Medline was conducted to identify peer-reviewed articles related to safety and efficacy. A total of 47 publications were identified and reviewed herein. The literature supports the use of antibiotic/antiiflammatory combination ear drops in the treatment of both acute otitis externa and acute otitis media in pediatric patients with tympanostomy tubes. Ciprofloxacin/dexamethasone has been demonstrated as safe and effective with regard to clinical cures and microbiological eradication of pathogens in either disease with low treatment failure rates. Additionally, the literature also provides clear evidence for the contribution of dexamethasone when added to ciprofloxacin for the topical treatment of ear infections.

Pharmacokinetics of CIPRODEX otic in pediatric and adolescent patients

OBJECTIVE

Describe the pharmacokinetics of ciprofloxacin and dexamethasone after administration of CIPRODEX Otic Suspension (CIP/DEX) into the middle ears of children.

DESIGN

Open-label, single-dose, pharmacokinetic studies, administering four drops of CIP/DEX instilled into each middle ear through the tympanostomy tubes immediately following tube placement. Blood was collected for 6h and analyzed for ciprofloxacin and dexamethasone concentrations using a validated liquid chromatography and tandem mass spectrometry (LC/MS/MS) method.

SETTING

The study was conducted through a referral pediatric otolaryngology practice with actual surgical procedures performed in an ambulatory care center.

PATIENTS

Twenty-five randomly selected patients, 1-14 years of age (mean age, 5 years), receiving tympanostomy tubes.

RESULTS

Peak ciprofloxacin plasma levels were observed at about 1h, with a mean C(max) of 1.33+/-0.96 ng/mL (range <0.5-3.45 ng/mL) and an estimated half-life of 3.0+/-1.2h. Peak dexamethasone plasma levels were observed within 2h with a mean C(max) of 0.90+/-1.04 ng/mL (range <0.05-5.10 ng/mL) and an estimated half-life of 3.9+/-2.9h.

CONCLUSION

These results demonstrated low systemic exposure of ciprofloxacin and dexamethasone following topical otic administration in pediatric patients.

Round window gentamicin absorption: an in vivo human model

OBJECTIVE/HYPOTHESIS

Using a novel human labyrinthine sampling model, in vivo gentamicin absorption through the round window can be measured.

STUDY DESIGN

A prospective study.

METHODS

Gentamicin was delivered either transtympanically (preoperative) or through a facial recess approach (intraoperative). The lateral semicircular canal and vestibule were opened, and by means of a microsyringe, labyrinthine fluid was aspirated. A sample of serum was also drawn. In all patients cerebrospinal fluid was also drawn. The samples were analyzed using a standard chemistry analyzer.

RESULTS

Intratympanic gentamicin diffused through the round window membrane and achieved concentrations in the labyrinthine fluid ranging from 0 to 16 mg/L. Intratympanic gentamicin was absorbed into the systemic circulation in 4 of 11 patients with serum levels ranging from 0.3 to 0.4 mg/L. No gentamicin was detected in the cerebrospinal fluid.

CONCLUSIONS

Intratympanic gentamicin diffuses rapidly through the round window membrane and achieves significant levels in the inner ear. Thus, this new model can be used to assess round window permeability to clinically relevant medications such as steroids and ototopical antibiotics.