Case presentation
A 31-year-old woman presented with a 1-year history of purplish-red
papules, nodules, and blisters symmetrically distributed on her scalp,
trunk, and limbs (Fig. 1). The patient had a previous history of
pulmonary tuberculosis. Laboratory test results of the patient show
elevated serum levels of IgG (356.2 mg/dL; normal range, 60–160mg/dL)
and IgA (37.6 mg/dL; normal range, 7–36 mg/dL). Reduced level of C3 (75
mg/dL; normal range, 79–152 mg/dL) and C4 (12 mg/dL; normal range,
16–38 mg/dL) were observed. A monoclonal band was observed as IgA-λ
paraprotein on serum electrophoresis. The serum complement profile
showed reduction of C3 (64.8 mg/dL; normal range, 79–152 mg/dL) and C4
(11.9 mg/dL; normal range, 16–38 mg/dL). Examinations for hepatitis B
and HIV were negative. Full blood count, renal and liver function tests,
and autoimmune antibodies such as antinuclear antibodies were all within
the normal range. A biopsy from the left foot specimen presented a
significant increase of neutrophils, fragmented nuclei, and fibrinoid
necrosis of vascular tissue in the middle and deep layers of the dermis
(Fig. 2).
According to the clinical manifestation and auxiliary examination
results, the diagnosis of erythema elevatum diutinum was considered.
Initial therapy included methylprednisolone and dapsone, beginning at
40mg/d and 100mg/d, respectively. Colchicine 1g/d and dapsone 200mg/d
were subsequently added to her treatment regimen because this patient
had a poor response to dapsone and corticosteroid and her condition
continued to deteriorate. Subsequently, after continuous IVIg
(intravenous immunoglobulin) 22.5g/d for 5 days, the patient’s condition
was quickly stabilized. After a one-month follow-up, most of the plaques
subsided and the papules flattened.