A morphometric analysis of bulbar urethral strictures.
In a beautifully descriptive paper, authors from Rio de Janeiro and San Francisco report a quantitative and qualitative histological analysis of spongiosal tissue in patients with bulbar urethral strictures. They found that stricture formation was characterised by major alterations in extracellular matrix features.


OBJECTIVE
To report a quantitative and qualitative histological analysis of spongiosum tissue in patients with bulbar urethral strictures.


METHODS
Urethral specimens from 15 patients who had end-to-end anastomotic urethroplasty were evaluated; the control group comprised five bulbar urethras from cadavers. The collagen content, elastic fibres, smooth muscle and vessels were analysed using stereological methods.


RESULTS
There was complete loss of the relationship between smooth muscle, extracellular matrix and sinusoids in the peri-luminal area (PLA), with collagen replacement. The extension of the fibrotic area was greater in those with a traumatic than in those with an atraumatic stricture. The content of smooth muscle and collagen in the peripheral spongiosum (PS) area was similar for the stricture and control groups, and results were comparable for traumatic and atraumatic groups and those with suprapubic cystostomy diversion or not before surgery. There was a remarkably lower vascular density in the traumatic than in the atraumatic group. There was an increase in type III collagen in the PLA and in type I collagen in the PS; collagen type III in the PLA was greater in the group with no suprapubic cystostomy diversion before surgery. There were fewer elastic fibres in both stricture areas (PLA and PS) than in the control group.


CONCLUSIONS
Urethral stricture formation is characterized by marked changes in extracellular matrix features, with consequent changes in organ function.
Cavalcanti
Andre G
AG
Urogenital Research Unit, State University of Rio de Janeiro, and Department of Urology, Souza Aguiar Municipal Hospital, Rio de Janeiro, Brazil.
Costa
Waldemar S
WS
Baskin
Laurence S
LS
McAninch
Jack A
JA
Sampaio
Francisco J B
FJ
D000328:Adult; D000368:Aged; D003094:Collagen / Q000378:metabolism*; D004547:Elastic Tissue / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009130:Muscle, Smooth / Q000473:pathology*; D014521:Urethra / Q000098:blood supply / Q000473:pathology*; D014525:Urethral Stricture / Q000473:pathology* / Q000601:surgery
D003094:Collagen