title: A protocol for microbiologically safe preparation, storage, and use of autologous serum eye-drops in low-income countries.
abstract: BACKGROUND
  The study aimed to investigate whether the preparation, storage, and use of autologous serum in insulin syringes is microbiologically safe.
  
  
  METHODS
  Blood samples (10 mL) were obtained from 10 volunteers. After centrifugation, the supernatant serum was removed and distributed in 5 sterile insulin syringes for each sample; syringes were numbered 0 to 4 and labelled with the subject's details. Syringes were immediately transported to the microbiology laboratory and stored in a refrigerator at +4°C. The "0" labelled syringes were separated from the others and 100 µl of serum from each syringe was immediately seeded on chocolate and Sabouraud agar plates, which were incubated aerobically at 37°C for 96 hours to detect any bacterial and/or fungal contamination. In the next 4 days, the same procedure was repeated for the remaining syringes: on day 1, the "1" labelled syringes were analyzed; on day 2, the "2" labelled ones, and so on. In a second experiment, blood samples were obtained from 5 different volunteers. The same procedure as above was followed, but each syringe was used for repeated cultures at 2-hour intervals, for a total of 12 cultures/day. The needle was removed and replaced for each inoculation and the syringes were stored in the refrigerator after use.
  
  
  RESULTS
  Under these experimental conditions, none of the cultures showed microbial growth.
  
  
  CONCLUSIONS
  Results suggest that, under the protocol described, preparation, storage and use of undiluted autologous serum in insulin syringes is inexpensive, fast, and microbiologically safe. This is of great importance for low-income countries.
authors.affiliation: University of Sassari, Sassari, Italy. francescobla@tiscali.it.
authors.forename: Francesco
authors.initials: F
authors.lastname: Blasetti
authors.forename: Donatella
authors.initials: D
authors.lastname: Usai
authors.forename: Salvatore
authors.initials: S
authors.lastname: Sotgia
authors.forename: Ciriaco
authors.initials: C
authors.lastname: Carru
authors.forename: Stefania
authors.initials: S
authors.lastname: Zanetti
authors.forename: Antonio
authors.initials: A
authors.lastname: Pinna
mesh_terms: D003906:Developing Countries; D004339:Drug Compounding / Q000379:methods*; D004340:Drug Contamination / Q000517:prevention & control*; D004356:Drug Storage / Q000379:methods; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008828:Microbiological Techniques; D009883:Ophthalmic Solutions / Q000008:administration & dosage* / Q000009:adverse effects; D012034:Refrigeration; D044967:Serum / Q000382:microbiology*; D013594:Syringes
chemical_list: D009883:Ophthalmic Solutions