The Antibiogram and Outcomes of Antimicrobial Regimens in Microbial Keratitis: A Prospective Cohort Study
Condition: Bacterial Keratitis; Fungal Keratitis; Mixed Bacterial and Fungal Keratitis; Microbial Keratitis
MeSH terms: Keratitis
Study type: Observational

Summary: 
      This study is an observational prospective cohort study which aims to generate an antibiogram
      and to assess the clinical responses and outcomes of microbial keratitis patients, treated
      with empiric topical antimicrobial therapies, with the main objective being to recommend the
      most effective empiric therapy. Microbial keratitis patients are attending the Cornea
      Outpatient Clinic at Alexandria Main University Hospital, Alexandria, Egypt.
    

Detailed description: 
      The main objective of this observational study is to recommend the most effective empiric
      topical antimicrobial therapy in microbial keratitis, according to the current local
      antimicrobial resistance data and the clinical outcomes of patients with bacterial, fungal,
      and mixed bacterial and fungal keratitis being treated with different empiric topical
      antibiotics and antifungal therapies.

      In the study, test results of routinely performed culture and sensitivity on corneal scraping
      samples and on contact lenses in indicated severe, centrally located, and large ulcers are
      collected and analyzed. The sensitivity data is utilized to generate an antibiogram to
      describe the local prevalence of bacteria and fungi causing microbial keratitis and to
      investigate the prevalence of antimicrobial resistance.

      Results of the culture and sensitivity are often delayed, hence empiric broad- spectrum
      antimicrobial therapy is ideally started after corneal scraping, until laboratory test
      results are obtained. Broad-spectrum empiric therapy will be modified into a more selective
      culture- guided therapy if the causative agent and its antimicrobial sensitivity are
      identified.

      Empiric therapy continues in cases where the culture results are negative together with
      clinical improvement. Also, when patients have already been on empiric treatment before
      presenting to the clinic, corneal scraping and culture are not performed.

      In the study, microbial keratitis patients diagnosed as either bacterial, fungal, or mixed
      bacterial and fungal keratitis, taking the empiric topical antimicrobials, are observed. The
      study investigator 's role is to observe and study the clinical responses and treatment
      outcomes of microbial keratitis patients who are on different empiric antimicrobial therapies
      as part of the routine medical care. There is no assignment of any intervention to the study
      participants. The investigator does not intervene, and does not prescribe, recommend, or
      assign any intervention to the study participants.

      The clinical response of microbial keratitis patients, who are on different empiric
      antibiotics and antifungal eye drops, is studied by determining the primary and secondary
      outcomes. Measured outcomes include corneal ulcer healing, time to epithelialization,
      improvement in visual acuity, rates of surgical interventions and complications.
    

Intervention name(s): Moxifloxacin Ophthalmic 0.5% Ophthalmic Solution; Ceftazidime 5% + vancomycin 5%; Gentamicin 1.4% + vancomycin 5%; Natamycin 5% Oph Susp; Voriconazole 1%; Natamycin 5% + voriconazole 1%; Natamycin 5%+ ceftazidime 5% + vancomycin 5%; Voriconazole 1% + ceftazidime 5% + vancomycin 5%
Intervention type(s): Drug; Drug; Drug; Drug; Drug; Drug; Drug; Drug
Intervention description(s): In the observational study, patients treated with topical antibiotic moxifloxacin 0.5% eye drops as part of routine medical care are observed. The investigator does not assign any specific intervention to the study participants.; In the observational study, patients treated with topical fortified antibiotics ceftazidime 5% and vancomycin 5% eye drops as part of routine medical care are observed. The investigator does not assign any specific intervention to the study participants.; In the observational study, patients treated with the topical fortified antibiotics gentamicin 1.4% and vancomycin 5% eye drops as part of routine medical care are observed. The investigator does not assign any specific intervention to the study participants.; In the observational study, patients treated with the topical natamycin 5% antifungal eye drops as part of routine medical care are observed. The investigator does not assign any specific intervention to the study participants.; In the observational study, patients treated with voriconazole 1% antifungal eye drops as part of routine medical care are observed. The investigator does not assign any specific intervention to the study participants.; In the observational study, patients treated with the topical natamycin 5% and voriconazole 1% antifungals eye drops as part of routine medical care are observed. The investigator does not assign any specific intervention to the study participants.; In the observational study, patients treated with the topical natamycin 5% and antifungal and the fortified antibiotic ceftazidime 5% and vancomycin 5% eye drops as part of routine medical care are observed. The investigator does not assign any specific intervention to the study participants.; In the observational study, patients treated with the topical voriconazole 1% antifungal and the fortified antibiotics ceftazidime 5% and vancomycin 5% eye drops as part of routine medical care are observed. The investigator does not assign any specific intervention to the study participants.
Other intervention name(s): Vigamox®; (CAZ-VAN); (GEN-VAN); Vfend®; (NT-VRC); (NT-CAZ-VAN); (VRC-CAZ-VAN)
Intervention MeSH terms: Moxifloxacin; Vancomycin; Gentamicins; Ceftazidime; Natamycin; Voriconazole; Ophthalmic Solutions
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Bacterial keratitis, fungal keratitis, and mixed bacterial and fungal keratitis patients
        attending the Cornea Outpatient Clinic at Alexandria Main University Hospital.
      
Keywords: Microbial keratitis; Infectious corneal ulcer; Bacterial keratitis; Fungal keratitis; Mycotic keratitis; Antibiogram; Antimicrobial resistance; Culture; Sensitivity; Fortified antibiotics eye drops; Moxifloxacin; Natamycin; Voriconazole; Prevalence; Antifungal eye drops; Bacteria; Fungi; Vancomycin; Ceftazidime; Gentamicin; Mixed bacterial and fungal keratitis