‘Haematoxylin and eosin’ with a difference (but OH, what a difference!)

Abstract

Supplementing the standard H & E section with alcian blue gives valuable additional information in many cases. It may show that a particular carcinoma metastasis is mucin-producing; draw attention to mucinous degeneration of vessels, tumours and other tissues, or to some forms of amyloid; identify mast cells in skin and other sections; pinpoint cartilage cells in osteoid or tumours; reveal intestinal metaplasia in gall bladder or gastric mucosa; and many hundreds of other applications. The difficulty in practice is that the resultant section may not look sufficiently like the ordinary routine H & E to be acceptable for everyday use. Careful planning of, and the order in which, the various solutions are used, together with a technique that favours progressive staining rather than differentiation to obtain good contrast, has enabled this difficulty to be overcome. The resultant method may be used as an automated procedure on a staining machine; or for individual sections stained by hand. The final result looks just like an H & E section, except that mucopolysaccharides stain a clear blue, that is optically quite distinct from the grey-blue to grey-black of nuclei and other haematoxyphil material. Omission of the first stage results in a classical H & E-type section, with good differentiation of eosinophil from neutrophil polymorphs, muscle from collagen and so on. Reversing the order of Alcian Blue and Haematoxylin (HABET) results in stronger alcian blue staining of sulphomucins. This variant identifies the histiocytes in Whipple's disease, and distinguishes differences in intensity of staining between the mucus of small and large intestine—but connective tissue sulphomucin is so prominent that it may conceal important detail in some sections, and is likely to present an unfamiliar appearance to the pathologist whose previous experience has been limited to H & E. The ABHET method (Alcian Blue, ferric alum, Haematoxylin, and Erythrosin with Tungstophosphoric acid) is recommended as <i>the</i> routine stain for all biopsy and post-mortem material, rather than as a special stain for occasional use. Substitution of eosin Y for erthrosin may be preferred as this gives a more transparent section with less dominant reds.