Skeletal lesions in human tuberculosis may sometimes heal: an aid to palaeopathological diagnoses

In three to five percent of active cases of tuberculosis, skeletal lesions develop. Typically, these occur on the vertebrae and are destructive in nature. In this paper, we examined cases of skeletal tuberculosis from a skeletal collection (Galler Collection) with focus on the manifestation of bony changes due to tuberculosis in various body regions in association with antibiotic introduction. This skeletal collection was created in 1925-1977 by a pathologist at the University Hospital in Zürich, Ernst Galler. It includes the remains of 2426 individuals with documented clinical histories as well as autopsies. It contained 29 cases of skeletal tuberculosis lesions. We observed natural healing of vertebral lesions through several processes including fusion of vertebrae, bone deposition and fusion of posterior elements. In these cases, we observed a higher frequency and proportion of bone deposition and fusion of posterior vertebral elements where pharmacological agents were used. There were also four cases of artificial healing through surgically induced posterior spinal fusion. With the introduction of pharmaceutical treatments, the number of individuals with multiple tuberculous foci decreased from 80% to 25% when compared to individuals who did not receive any drug therapy. Investigation of comorbidities showed that pneumonia, pleuritis and being underweight were consistently present, even with pharmaceutical treatment. Our results have applications in palaeopathological diagnoses where healing and consequent bone deposition may complicate differential diagnoses.