“I have a rash all over my back.”

“Physical examination revealed a diffuse rash covering most of the patient’s back.”

One sentence overheard in conversation, the other appearing in a medical report; the former more colloquial, the latter more technical—but both correct, right? Well, not quite. While rash has been used in medical writings since at least the second half of the 19th century, current thought is that rash is a lay term lacking precision and specificity. Thus, while it is perfectly acceptable (and understandable) for a patient to use the term when describing symptoms to a clinician, once the clinician turns to describing an inflammatory (as opposed to a cystic or neoplastic) skin condition for the patient’s record or in a case report or other formal medical literature, rash should be replaced with a more descriptive and specific term.

However, this does not mean that rash has no place in medical literature. Because patients typically use rash when describing their symptoms, the term might legitimately appear, for example, in a report of a patient presenting with specific symptoms and signs or a list of adverse reactions self-reported by participants in a randomized trial; similarly, report forms provided to trial participants might also include rash in a list of potential adverse reactions.

Editors of medical literature, then, need to take into account the context in which rash was originally used as well as the intended audience. The term is appropriate when it appears in passages quoted from patients or when used in materials intended for lay use, eg, instruction sheets, patient care brochures, and medication inserts (however, use of the term skin rash in such materials is redundant and should be avoided [see 11.2.1, Redundant Words, in the AMA Manual of Style, pp 405-406 in print]). In many cases, as noted above, the term is also appropriate in more formal medical literature reporting nondermatological studies in which rash is one of several adverse events listed and any type of rash would be lumped together in one category. In literature describing physical examinations, specific skin-related adverse events, or dermatological studies, rash should be replaced with a more precise term. While skin eruption or dermatitis are often acceptable replacements, ideally the replacement term should be precise enough to describe the appearance of the lesion (eg, macule or patch vs papule, bulla, vesicle, nodule, or pustule) and the suspected specific cause (eg, allergy; heredity; irritation; bacterial, viral, and fungal infections). Replacement terms might also describe the distribution of inflammation and the histological structures involved.

The range of findings and topics reported in JAMA and the Archives Journals allows for the use of rash as well as more specific terms within a single family of publications. For example, rash does appear regularly in JAMA, since many studies in that journal report adverse events that include rash as a category. On the other hand, the editorial staff of the Archives of Dermatology always replaces rash with a more specific term, unless rash appears in material quoted from a patient.— Phil Sefton, ELS