References Establishing Normal Limits for Blood Hemoglobin Concentration

plauded for developing assay techniques for protein identification that are at least available for problematic cases and for offering their help with characteristic generosity. Needless to say, the clinical constraints are most daunting. Patients will often get sicker while waiting for a diagnosis. Therefore, on occasion, the need arises to make the best guess as to the cause of amyloid disease in a patient with 2 possible amyloid proteins. Discussion with the patient and with colleagues, as well as sharing of material in pursuit of the diagnosis, should be part of this process. Transthyretin tissue staining is often helpful, but as Solomon et al rightly note, the results of immunohistochemical staining for amyloid type can be “misleading or negative.” Finally, with respect to the innovative techniques needed, I had in mind the development of small reactive peptides specific for amyloid from different types of protein and validated for use in appropriately prepared tissue specimens.5 The pursuit of such reagents clearly follows both the dreams and footsteps of alchemists.