The Case of the Vanishing Diagnosis
As revisions to APA's Diagnostic and Statistical Manual (DSM) have reflected, our understanding of psychiatric disorders has evolved over time. For example, consider the diagnosis of pellagra—it has virtually vanished.
Pellagra, with its triad of dermatitis, dementia, and diarrhea, is rarely seen today, but less than a hundred years ago it was a major reason for admission to mental hospitals in the United States, particularly in the southern states.
As late as 1930-32, the state hospital in Goldsboro, N.C., for example, reported that pellagra was responsible for 19 percent of all admissions.
In 1863 John Gray, M.D., editor of the American Journal of Insanity (AJI), published a report in the journal of a case of pellagra with psychosis at his hospital in Utica, N.Y. In 1906 Reuben Searcy reported an epidemic of 88 cases at his psychiatric hospital in Alabama. In 1908 the staff of South Carolina's state hospital published a literature review and a review of pellagra-related cases in the AJI, and in 1912 another report from that hospital stated that 28 percent of admissions were due to psychosis with pellagra. Case reports were published from other parts of the country, including Connecticut and Maine.
Pellagra had been known in Europe since the 18th century, but its presence in the United States was often denied by physicians and others. Osler's 1906 textbook, Practice of Medicine, said it did not occur in this country. The disease was thought to be due to spoiled maize (corn), but other suggested causes were infectious agents, toxins, and insect bites.
The discovery of the cause of pellagra rivals the story of Dr. John Snow, who ended an epidemic of cholera in 1854 simply by removing the handle of the Broad Street pump in London.
In 1914 Joseph Goldberger, a physician in the U.S. Public Health Service, was assigned to work on the problem of pellagra, which was reaching epidemic proportions. His observations in a Mississippi orphanage led to controlled studies in a Mississippi prison and at the state hospital in Milledgeville, Ga. He determined that pellagra was due to a nutritional deficiency curable by a diet containing milk and meat. By 1937, the chemistry of the disease was elucidated—tryptophan in the diet is a precursor of nicotinic acid (niacin), which is a necessary co-enzyme in cell metabolism.
During this period, the American Medico-Psychological Association (now APA) was concerned with the need for a classification of mental diseases. The first such classification was developed and adopted in 1917. It included the diagnosis of psychosis with pellagra. The rubric was retained in the 1934 revision and in 1942 was placed under “psychoses due to disturbances in metabolisms.”
The 1952 revision of DSM changed the rubric to “chronic brain syndrome associated with other disturbances of metabolism” and specifically included pellagra. The 1968 revision placed pellagra under“ psychoses with other physical conditions” and the subheading“ psychoses with other metabolic or nutritional disorders (including pellagra).”
The 1980 DSM-III, with its atheoretical and descriptive approach, makes no mention of pellagra, although it does mention toxic and metabolic disturbances as etiologic factors. DSM-III-R, published in 1987, changed the classification to “organic mental disorder of known etiology,” with mention of metabolic disorder but no reference to pellagra.
In 1994 DSM-IV used the term “dementia due to (indicate general medical condition)” and mentions vitamin B-12 but not pellagra. An appendix to that volume showing ICD-9-CM codes for selected medical conditions lists pellagra (niacin deficiency) under “nutritional diseases.”
Most recently, DSM-IV-TR notes in the chapter “Delirium, Dementia, and Amnestic and Other Cognitive Disorders” that the etiology of these disorders is either a general medical condition or due to the effects of a substance.
The story of pellagra is a classic example of how psychiatry has progressed as new knowledge unfolds. ▪
