title: Histopathological kidney alterations in rats naturally infected with Leptospira.
abstract: BACKGROUND
  Histopathological changes by Leptospira in naturally infected rodent reservoirs have been poorly described.
  
  
  OBJECTIVE
  The aim of the current study is to describe renal histopathology associated with leptospirosis infection of naturally infected rodents captured in the urban area of the city of Medellin, Colombia.
  
  
  METHODS
  We performed hematoxilin-eosin (H-E) on kidney samples collected from 254 captured rodents. The positive samples were processed by Warthin Starry (W-S) staining and PCR-LipL 32.
  
  
  RESULTS
  Fifty one rodent kidneys showed H-E histopathological changes that consisted of inflammatory infiltrate with lympho-plasmocitary cells and histiocytes. We performed W-S staining and PCR-LipL 32 to 67 kidney samples, including the 51 that had shown detectable changes by H-E and 16 (8%) of 203 rodents with negative results. Eight of the samples that tested positive for H-E (15.7%) were also positive for W-S staining. All negative for H-E were also negative for W-S staining. Of the W-S positive samples also tested for culture only three tested positive for both. Additionally, 47 (92.1%) samples positive for H-E were positive for PCR; while eleven of the 16 (68.8%) negative for H-E were positive for PCR. The samples positive for PCR were subsequently tested for culture and 11 (23.4%) were positive. Seven samples were positive for PCR and W-S and three were positive for PCR, W-S and culture. All of the PCR-LipL 32 fragments were sequenced and showed specific amplicons for L. interrogans .
  
  
  CONCLUSIONS
  The Leptospira infection was confirmed in all of the animals tested. The only histological kidney lesion attributable to leptospiral infection in the reservoir was interstitial nephritis.
authors.affiliation: Grupo de Medicina Tropical, Instituto Colombiano de Medicina Tropical-Universidad CES, Medellín, Colombia.
authors.forename: Piedad
authors.initials: P
authors.lastname: Agudelo-Flórez
authors.affiliation: Grupo de Medicina Tropical, Instituto Colombiano de Medicina Tropical-Universidad CES, Medellín, Colombia.
authors.forename: Victoria Eugenia
authors.initials: VE
authors.lastname: Murillo
authors.affiliation: Grupo Centauro, Facultad de Ciencias Agrarias, Universidad de Antioquia, Medellín, Colombia.
authors.forename: Andrés Felipe
authors.initials: AF
authors.lastname: Londoño
authors.affiliation: Grupo Centauro, Facultad de Ciencias Agrarias, Universidad de Antioquia, Medellín, Colombia.
authors.forename: Juan David
authors.initials: JD
authors.lastname: Rodas
mesh_terms: D000818:Animals; D000835:Animals, Wild / Q000382:microbiology*; D058070:Asymptomatic Diseases; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics; D001437:Bacteriuria / Q000382:microbiology / Q000662:veterinary; D003105:Colombia; D004197:Disease Reservoirs / Q000382:microbiology*; D005260:Female; D007668:Kidney / Q000382:microbiology / Q000473:pathology*; D007684:Kidney Tubules / Q000382:microbiology; D007919:Leptospira / Q000235:genetics / Q000302:isolation & purification; D007922:Leptospirosis / Q000662:veterinary*; D008074:Lipoproteins / Q000235:genetics; D008297:Male; D009395:Nephritis, Interstitial / Q000382:microbiology / Q000473:pathology / Q000662:veterinary; D009924:Organ Culture Techniques; D016133:Polymerase Chain Reaction; D051381:Rats / Q000382:microbiology*; D012376:Rodent Diseases / Q000382:microbiology / Q000473:pathology*; D013194:Staining and Labeling / Q000379:methods; D014504:Urban Health
chemical_list: D001425:Bacterial Outer Membrane Proteins; C406589:LipL32 protein, Leptospira; D008074:Lipoproteins