title: Combination therapy with ampicillin and azithromycin in an experimental pneumococcal pneumonia is bactericidal and effective in down regulating inflammation in mice.
abstract: OBJECTIVE
  Emergence of multidrug resistance among Streptococcus pneumoniae (SP), has limited the available options used to treat infections caused by this organism. The objective of this study was to compare the role of monotherapy and combination therapy with ampicillin (AMP) and azithromycin (AZM) in eradicating bacterial burden and down regulating lung inflammation in a murine experimental pneumococcal infection model.
  
  
  METHODS
  Balb/C mice were infected with 106 CFU of SP. Treatments with intravenous ampicillin (200 mg/kg) and azithromycin (50 mg/kg) either alone or in combination was initiated 18 h post infection, animals were sacrificed from 0 - 6 h after initiation of treatment. AMP and AZM were quantified in serum by microbiological assay. Levels of TNF-α, IFN-γ IL-6, and IL-10 in serum and in lungs, along with myeloperoxidase, inflammatory cell count in broncho alveolar lavage fluid, COX-2 and histopathological changes in lungs were estimated.
  
  
  RESULTS
  Combination therapy down regulated lung inflammation and accelerated bacterial clearance. This approach also significantly decreased TNF-α, IFN-γ, IL-6 and increased IL-10 level in serum and lungs along with decreased myeloperoxidase, pulmonary vascular permeability, inflammatory cell numbers and COX-2 levels in lungs.
  
  
  CONCLUSIONS
  Combinatorial therapy resulted in comparable bactericidal activity against the multi-drug resistant isolate and may represent an alternative dosing strategy, which may help to alleviate problems with pneumococcal pneumonia.
authors.forename: Arnab
authors.initials: A
authors.lastname: Majhi
authors.forename: Kiran
authors.initials: K
authors.lastname: Kundu
authors.forename: Rana
authors.initials: R
authors.lastname: Adhikary
authors.forename: Madhubanti
authors.initials: M
authors.lastname: Banerjee
authors.forename: Sayantika
authors.initials: S
authors.lastname: Mahanti
authors.forename: Anirban
authors.initials: A
authors.lastname: Basu
authors.affiliation: Department of Physiology, Immunology laboratory, University of Calcutta, University Colleges of Science and Technology, 92 APC Road, Calcutta 700009, West Bengal,India. biswadevbishayi4@gmail.com.
authors.forename: Biswadev
authors.initials: B
authors.lastname: Bishayi