The Need for Consensus on Primary Familial Brain Calcification Nomenclature

Primary familial brain calcification is characterized by the presence of symmetrical and bilateral brain calcifications, mainly on the basal ganglia but also on other brain structures, such as the thalamus, cerebellum, and cerebral white matter.¹ Over the years, a variety of names have been associated with this disease, and the commonly used eponym, “Fahr’s disease,” has slowly been substituted by other terms, following a tendency seen in medicine as a whole.^2,3

Although Fahr’s disease was first described in 1850 in France, its name refers to Karl Theodor Fahr, the German physician who described the disorder 80 years later.^4,5 (Figure 1) The eponym was used for the first time in 1951,⁶ and variations of it are seen, ranging from possessive to nonpossessive forms, as well as from syndrome to disease. This results in four different variations of the original eponym: Fahr’s disease, Fahr disease, Fahr’s syndrome, and Fahr syndrome. Furthermore, since 1952 a large selection of terms has been used in the literature when referring to this disorder, and more recently there has been a tendency to move toward biologically based names.^3,7

The diminished use of eponyms is not exclusive to Fahr’s disease. Although common in the past, it has fallen in popularity among researchers and physicians around the world for several reasons. The main reason is that in recent years the scientific community has mostly agreed that disease names should focus primarily on conveying the underlying cause of the disease, not on the physician who first described it.³ Some disadvantageous aspects related to the use of eponyms include the possibility of several names being attributed to a single disorder, which can generate confusion, as well as the use of a single eponym to describe different disorders.² In addition, some eponyms are being avoided due to the connection between the physicians honored and unethical practices.⁸ On the other hand, it can be argued that the use of eponyms makes referring to a disease easier—especially for patients—saves physicians time, and prevents misunderstanding.^9,10 Some well-known examples of commonly used eponyms include Alzheimer’s, Parkinson’s, and Huntington’s disease, and there is no indication that these terms will be discontinued any time soon. Regardless, the use of the correct term when referring to a disease is important not only to ensure that no confusion is generated between health care providers and researchers but also in order to represent the disease in its entirety.¹¹

With regard to Fahr’s disease, the names used from 1951 until now include, but are not limited to, the four Fahr eponyms, idiopathic basal ganglia calcification,¹² and primary familial brain calcification,¹³ resulting in a total of more than 35 different names.¹⁴ The terms mentioned above are the most commonly used, and there appears to be no exact criteria to distinguish them or to define when one is used over the others. Use of the correct nomenclature is especially important for this disease, because the term used has the capacity to identify whether the patient’s calcifications developed primarily, when they can be attributed to genetics, or whether they developed secondarily in response to traumatic, metabolic, or infectious stimuli.¹

Taking this into consideration, here we aimed to compare the use of different terms used when referring to primary familial brain calcification throughout the years and, possibly, to identify a tendency from the research community to abolish or adopt a specific term.