A reliable silver staining method for identification of Pneumocystis carinii in histologic sections.

The acquired immune deficiency syndrome (AIDS) is characterized by the development of Kaposi's sarcoma and several opportunistic infections including pneumonia caused by Pneumocystis carinii. As a staining method for Pneumocystis carinii, the methenamine-silver nitrate method has been used routinely. Most of fungi can be stained easily by this technique but the identification of Pneumocystis carinii is not always easy. The author has improved the method by using ammoniacal silver nitrate and found that this was a reliable staining method for Pneumocystis carinii. Moreover, this method proved to be superior to others in demonstrating Pneumocystis carinii in histologic sections.