Discontinuous polyostotic fibrous dysplasia with multiple systemic disorders and unique genetic mutations: A case report

Figure 1 Photographic images of the patient showing signs of Cushing syndrome. A-C: Abdominal obesity with thin arms and legs, acne, a round face and a fat lump between the shoulders (orange arrows); D: Poorly developed teeth; E and F: Thumb duplication on the left hand (orange arrow).

Figure 2 Radiography examination results. A: Anterior view; B: Posterior view of skeletal scintigraphy showing the location of the bone lesions on left ischium and left fibula, talus, and calcaneus (orange arrows); C and D: Computed tomography shows well-circumscribed bone lucencies and ground-glass opacities in left talus and calcaneus (yellow arrows).

Figure 3 Pathological reports. A: Fibrous and osseous tissue are present in varying proportions [hematoxylin-eosin (HE), 40 ×]. The box shows the view field of B; B: The fibrous tissue is composed principally of bland fibroblastic cells. Mitoses are uncommon (HE, 100 ×). The box shows the view field of C; C: The osseous component is comprised of irregular, curvilinear, trabeculae of woven or rarely lamellar woven bone (HE; 200 ×).

Figure 4 Sequencing chromatograms of the analyzed genes. A: Results for HSPG2; B: Results for RIMS1. The red arrows indicate the variants in HSPG2 (c.6913G>A, p.Asp2305Asn) and RIMS1 (c.3139del, p.Thr1047His). The variants indicate a maternal source.

Figure 5 Possible genetic pedigree: The inheritance of HSPG2 and RIMS1. The HSPG2 mutation is homozygous, while the RIMS1 mutation is heterozygous. The abnormal genotype of HSPG2 is likely caused by uniparental disomy, a single chromosome from her mother is duplicated leading to the homozygous mutation in HSPG2.