title: Quinine sulfate inhibits invasion of some bacterial skin pathogens.
abstract: BACKGROUND
  As some of the many patients who receive antimalarials for the treatment of noninfective inflammatory diseases (lupus erythematosus, collagen vascular diseases, rheumatoid arthritis, and others) are also immunosuppressed because of their disease and/or treatments, and may have concomitant bacterial infections, we investigated the effect of these drugs on the growth and invasion of several bacteria that are commonly associated with skin and soft tissue infections to determine whether they could protect against such conditions and obviate the need for an additional antibiotic drug.
  
  
  METHODS
  The effect of quinine sulfate (QS) at concentrations of 50 and 100 microm on the entry process of Enterobacter agglomerans, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae into Caco-2 cells was studied during the infection period. The invasive efficiency was expressed as the number of viable internalized bacteria obtained by counting the colony-forming units (CFUs).
  
  
  RESULTS
  The invasive ability of E. agglomerans and S. aureus was significantly inhibited by 50 and 100 microm QS in a dose-dependent manner when the drug was added to Caco-2 cell monolayers during the infection period; however, QS had no significant effect on the internalization of P. aeruginosa or K. pneumoniae.
  
  
  CONCLUSIONS
  Antimalarial drugs are currently widely used to treat patients with autoimmune dermatologic and rheumatologic diseases, and have also been recently proposed as additional therapy for patients with human immunodeficiency virus (HIV) infection. These patients, who are often immunocompromised, may receive a secondary advantage from these antimalarials, which may provide some protection against staphylococci (amongst the most important human pathogens causing many superficial and systemic infections) and E. agglomerans.
authors.affiliation: Dermatology Unit, Kaplan Medical Center, Rechovot, Israel. wolf_r@netvision.net.il
authors.forename: Ronni
authors.initials: R
authors.lastname: Wolf
authors.forename: Maria Antonietta
authors.initials: MA
authors.lastname: Tufano
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Ruocco
authors.forename: Elena
authors.initials: E
authors.lastname: Grimaldi
authors.forename: Eleonora
authors.initials: E
authors.lastname: Ruocco
authors.forename: Giovanna
authors.initials: G
authors.lastname: Donnarumma
authors.forename: Adone
authors.initials: A
authors.lastname: Baroni
mesh_terms: D000230:Adenocarcinoma; D000962:Antimalarials / Q000627:therapeutic use; D001419:Bacteria / Q000187:drug effects / Q000254:growth & development; D002455:Cell Division / Q000187:drug effects; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms; D018450:Disease Progression; D006801:Humans; D011803:Quinine / Q000627:therapeutic use*; D017192:Skin Diseases, Bacterial / Q000188:drug therapy* / Q000473:pathology*
chemical_list: D000962:Antimalarials; D011803:Quinine