Abstract
Objective: To study effective restaining techniques for discolored cytological slides Subject and Procedure: Cytological slides, mainly positive cases, from gynecological, respiratory, urinary and body cavity fluid samples, composed of discolored Papanicolaou (PAP) and Giemsa-stained slides were examined. After the removal of coverslips from the PAP-stained slides using xylene, they were processed in various ways, including immersion in phosphate buffer solution or a sodium citrate buffer solution, to analyze the mounting medium removal time, immersion time in a buffer solution, pH and reproducibility. The faded Giemsa-stained slides were immersed in the sodium citrate buffer solution (pH 6.8) before restaining with the Giemsa stain. Result: The immersion in phosphate buffer solution of approximately pH 7.0 for over three hours gave good results in the case of the faded PAP-stained slides. The sodium citrate buffer solution also showed some effect but the most effective was the phosphate buffer solution. The faded Giemsa-stained slides were somewhat improved but their result was not as good as that of the PAP-stained slides owing to the red cells being overstained in blue. Conclusion: The technique that we designed using phosphate buffer solution was considered useful for restaining valuable but discolored slides from previous examinations. We will further study problems including an improved restaining of faded Giemsa-stained slides.
