Life-threatening fungal infections have increased significantly in the past decade due to the rising number of immunocompromised patients. Serological diagnosis of most fungal infections is unreliable and blood cultures are positive in only 50% of premortem cases; therefore, tissue sampling together with fast, reliable staining of fungi should be carried out to reach the correct, timely diagnosis. We developed, partly serendipitously, a microwave silver staining method for fungi in histological sections. During a differentiation step in periodic acid, background staining is removed. This rapid staining method can be combined with immunostaining, for example, the alpha smooth muscle actin method, to visualize blood vessels. Silver staining results were optimized using the recently developed MicroMED BASIC microwave labstation for histology (Milestone srl, Italy), featuring no-touch temperature measurements and PC control.
Copyright 1998 Academic Press.