Association Between SNP of SP-D and Susceptibility and Prognosis of Infectious Keratitis
Condition: Infectious Keratitis
MeSH terms: Communicable Diseases; Infections; Keratitis
Study type: Observational [Patient Registry]

Summary: 
      This study explores the association between single nucleotide polymorphism (Met11Thr) of
      surfactant protein D(SP-D) and susceptibility and prognosis of infectious keratitis.Met11Thr
      of SP-D of patients with keratitis and normal controls were compared.Allele and genotype
      frequencies of patients with keratitis and normal controls were determined by polymerase
      chain reaction with sequence specific primers(PCR-SSPs) .SP-D gene polymorphism of patients
      with keratitis and normal controls was detected by Sanger sequencing
    

Detailed description: 
      Surfactant protein D(SP-D) plays an important role in the innate immune system of the eye in
      the lacrimal duct, cornea and conjunctiva.The single lipopolysaccharide on the surface of
      bacteria and the receptors on the surface of immune cells are linked by SP-D ,which acts as a
      bridge to neutralize viruses in the innate immune defense system and assists other immune
      cells in clearing bacteria and fungi.SP-D can also participate in the acquired immune
      response after combining with lipopolysaccharide on the surface of microorganisms.Some single
      nucleotide polymorphisms of SP - D can not only affect the plasma level of SP - D, which
      leads to the differences of pathogen defense capability, but also can affect the space
      configuration and structure of carbohydrate recognition domain of SP-D, causing the change of
      ability of SP - D combined with pathogens to influence its defensive role.The concentration
      of SP - D in ocular surface is closely related to the occurrence and progression of
      infectious keratitis.Association between single nucleotide polymorphisms of SP-D and the
      occurrence and development of infectious keratitis has yet to be confirmed by research.
    

Intervention name(s): Treatment of bacterial keratitis; Treatment of fungal keratitis; Treatment of viral keratitis; corneal scraping; Sequencing
Intervention type(s): Drug; Drug; Drug; Diagnostic Test; Other
Intervention description(s): 0.3% Levofloxacin Eye Drops or 0.3% Tobramycin Eye Drops QID; 1% Fluconazole Eye Drops or 0.25% Amphotericin B Eye Drops QID; 0.1% Acyclovir eye drops QID ，Ganciclovir gel QN，Famiclovir tablets 0.25g TID; culture and sensitivity of corneal ulcerated infiltrating edge tissue; polymerase chain reaction with sequence specific primers(PCR-SSP) and Sanger sequencing
Observational model: Case-Control
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        patients with infectious keratitis at 2nd Affiliated Hospital, School of Medicine, Zhejiang
        University, China between October 2016 to June 2019
      
Biospecimen description: 
      6ml peripheral venous blood in healthy control populations and in patients with infectious
      keratitis.

      ulcerated marginal tissue in patients with infectious keratitis.
    
Keywords: Infectious Keratitis; surfactant protein D; single nucleotide polymorphisms; Met11Thr; rs721917