Leprosy in Premodern Medicine: A Malady of the Whole Body (review)

Leprosy may popularly be associated with danger, fear, revulsion, and moral or spiritual contamination, but physicians historically have dealt with it as a somatic disease. While surveying a broad range of sources over a long history, Luke Demaitre pays close attention to the classic texts of Galen, Aretaeus, and Avicenna along with dozens of later writers, especially Bernard de Gordon in the fourteenth century, Ambroise Paré in the sixteenth, and Isaac Uddman in the eighteenth.

Differences between theoretical positions of Galen and Avicenna resulted in definitions and interpretations of “bewildering diversity” (109), despite attempts at resolution from the fourteenth century onward. From Montpellier came the influence of a “new” Galen, according to which liver failure (following Avicenna despite the anti-Arabism of the medical humanists) was identified as the source of leprosy’s corruptio in the body.

The etiology of leprosy was poorly understood, and the very Latin or vernacular terms used to name and charactize it were very fluid: “tangled” (85) and “unstable” (194). From the beginning, authors called it both lepra and elephantiasis, Renaissance medical humanists preferring the latter term. Garbled terminology added to difficulty of diagnosis and to historians’ retrospective diagnoses.

The premodern pathology of leprosy relied on the notion of black bile overwhelming and corrupting blood, resulting in a disease of the whole body. This corruptio reinforced the popular image of leprosy as unclean, repulsive, and malus. According to Demaitre, “conceptual” definitions and terminology, along with humoral explanations in examination reports, gave way by the seventeenth century to more “experiential” approaches (30), especially when learned physicians began replacing nonmedical personnel on examination juries.

Although leprosy’s symptoms were ambiguous, the stakes in its diagnosis —lifetime social isolation — were very high for both the individual and the community, so examiners carried out their work with “agonizing” precision (235), most often judging a patient clean (or, at most, predisposed). Eager to exploit this situation, many would-be mendicants sought certificates of infection in order to benefit from charity or hospitalization.

Demaitre describes the protocol for the examinations that led to diagnosis and sought to place verdicts in the context of authoritative medical writings. In mainly French and German archives, he found hundreds of certificates which also reveal personal, familial, and social contexts for the visitations.

Diagnosis was complicated by a “muiltifarious semiology” (256); the number of symptoms in checklists ranged from Avicenna’s twenty-nine to a list of fifty-two from fourteenth-century Montpellier (the most common signs from a dozen authorities are tabulated on page 220). Medical writers differed as to which signs were most telling, although facial symptoms were especially important for Bernard de Gordon and his followers. By the sixteenth century all-body symptoms relating to the Galenic faculties of natural, vital, and animal functions were cited more frequently than were signs linked to humoral disorders. At the same time, authors were focusing less on Galenic medical taxonomy and more on correlations or parallels with other diseases, notably cancer.

By the seventeenth century medical writers and examiners alike emphasized the contagious and, perhaps, hereditary (or congenital) aspects of the disease. Because leprosy affected the whole body rather than a single organ or member, medical writers remained convinced that this disease was incurable, even by religious rituals. Still, physicians who succeeded in treating it, thereby reversing the original diagnosis, were well paid; this underscores the ambiguity and uncertainty around diagnosis and confusion between “predisposition” and actual disease.

Preservative and palliative therapies drew on the doctrine of signatures; others on controlling “non-natural” lifestyle elements (mainly diet and sex); evacuating bad humors by bloodletting, purgatives, and baths; or employing antidotes like gold, seawater, snake meat, and (for Hildegard of Bingen) menstrual blood.

More than other diseases, leprosy presented a “chiaroscuro” (276) of signs, causes, diagnoses, and human responses. Like plague, its identity in this period is problematic, but its incidence apparently declined with...