case_images: PMC8184282_01
case_images: The photograph shows purpura on both legs. (A) Anterior view of the tibia. (B) Anterior view of the ankle.
case_images: TCRM-17-571-g0001.jpg
case_images: PMC8184282_01_TCRM-17-571-g0001.jpg
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case_images: Ten days after radiotherapy initiation, palpable purpura emerged on the lower extremities (Figure 1).
case_images: Histopathology of the palpable purpura and kidney. (A) The superficial dermis has perivascular infiltration of neutrophils, lymphocytes, and eosinophils. (B) Direct immunofluorescence using anti-IgA antibody reveals IgA deposition in the blood vessel walls of the dermal papillary layer. (C) The kidney has mesangial hypercellularity, increased mesangial matrix, and a cellular crescent. (D) Direct immunofluorescence using anti-IgA antibody shows mesangial IgA deposition.
case_images: TCRM-17-571-g0002.jpg
case_images: PMC8184282_01_TCRM-17-571-g0002.jpg
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case_images: Vasculitis in the kidney specimen was similarly noted (Figure 2B). IgA with C3 in the renal cells (Figure 2C) and in the superficial blood vessels of dermis (Figure 2D). In the present patient, treatment with methylprednisolone (500 mg/day) on days 1-3, followed by prednisolone (0.5 mg/kg/day), was initiated after a deterioration in renal function and a decline in urinary volume, as evidenced by a drop in the estimated glomerular filtration rate (eGFR) from 67.9 mL/min/1.73 m2 at the time of admission to 29.7 mL/min/1.73 m2 before starting prednisolone.