Exit-site study methods and results.

Contrary to peritonitis, where the clinical presentation is clearly different from that of normal, there is a spectrum of appearances from uninfected to infected exit sites. This led to imprecise definitions of exit-site infection, difficulties in interpreting the results of various studies, and many, varied treatment recommendations. We have performed 565 evaluations of 61 healed exit sites in 56 patients. The exit and the sinus were inspected using a Zeiss prism loupe with 4.5x magnification for the presence, absence, intensity, and/or characteristics of specific attributes such as swelling, color, crust, drainage, granulation tissue, and epithelium in the sinus. Pictures of the external exit and the visible sinus tract were then drawn and photographs of the exit site and visible sinus tract were taken. Visual attributes discerned by loupe inspection were verified by review of photographs. A new classification was developed with six distinct categories of exit appearances: acute infection, chronic infection, external cuff infection, equivocal, good, and perfect. Finally, the category of traumatized exit was established, because trauma may result in various appearances. The outcomes in each category were correlated with treatment measures in a 5-year longitudinal study. The validity of this classification and its applicability to clinical practice was subjected to further investigation in a cross-sectional study. Forty-five patients were evaluated only once by ZJT using a Zeiss prism loupe and by the primary nurse, who used a handheld magnifier. The features were recorded and classification was made. The results of loupe and magnifier evaluations were then compared regarding agreement in discerning features. In 41 evaluations (91%) there was agreement. The new classification may be useful in making treatment decisions, in reporting exit-site infection data, and in designing improved prospective, randomized studies.