Urethral cytology in spinal cord injury patients performing intermittent catheterisation

Local reactions of the urethral wall are known to occur by repeated introduction of a catheter in the urethra. Urethritis was found in 2-19% of patients practising intermittent catheterisation. Although the use of catheters of smaller size and the liberal use of lubricants may prevent urethral irritation and trauma, it was postulated that hydrophilic catheters (LoFric, Astra Tech Ltd, Stroud, England) induce significantly less trauma than PVC catheters because of the binding of the water molecules to the catheter surface which consists of polyvinylpyrrolidone and sodium chloride. Although urethritis and urethral stricture may represent one end of the spectrum of repeated urethral trauma, minor degrees of inflammation need to be quantitatively determined while assessing two different catheters for intermittent catheterisation. The degree of urethral inflammation in patients practising intermittent catheterisation was studied by urethral cytology and staining the smear by Papanicolaou's method. The number of neutrophil polymorphs and epithelial cells in three random high power fields in the urethral smear was counted and the percentage ratio of polymorphs to epithelial cells was calculated. Group 1 comprised 14 patients practising intermittent catheterisation with a PVC catheter and group 2 comprised 17 patients performing intermittent catheterisation with a LoFric catheter. There was no significant difference between the two groups as regards the age, diagnosis, size of the catheter used for intermittent catheterisation and the number of times that they performed catheterisation during a 24 hour period. Urethral cytology revealed a percentage (mean ratio) ratio of polymorphs to epithelial cells of 66 in group 1 and 0.04 in group 2. (< 0.0005).(ABSTRACT TRUNCATED AT 250 WORDS)