Because of the unusual occurrence of this condition it might be well to define it and consider it briefly from a historical standpoint.
Hematoporphyrin is described as hematin without the iron, and, in minute traces, occurs as a constant constituent of normal urine. Hematoporphyrin is frequently present in the urine in increased quantity in disease, but without being associated with any obvious change in the color of the urine. This form of hematoporphyrinuria is seen in many ailments and was first described in connection with measles and rheumatic fever. Again hematoporphyrin may occur in great excess in the urine associated with a distinctly abnormal color described as pink, dark brown, port wine or almost black. Until recently it was supposed that it was the hematoporphyrin which caused these abnormal colors, but we now know that other elements, as yet unrecognized, are responsible for this, since these changes in color occur