[IgA pemphigus accompanying multiple myeloma has disappeared following the treatment with bortezomib (Velcade), cyclophosphamide and dexamethasone. Case study and literature review].

IgA pemphigus, resembling subcorneal pustulous dermatosis, represents a rare complication of IgA type monoclonal gammopathy. The patient dates the onset of initial symptoms of vesicular-bullous disease to 1990. She was first examined at our clinic in 2001 with the following conclusion "type IgA monoclonal gammopathy of unknown significance". The first immunosuppressive treatment of vesicular-bullous disorder was administered in 2003 (dexamethasone 20 mg on days 1-4 and 15-18 in monthly cycles + daily cyclophosphamide 50 mg). Cyclophosphamide was administered for 6 months in total and dexamethasone for further 3 months. During the treatment, intensity of the skin disorder ameliorated and monoclonal IgA levels decreased to non-detectable levels. Nevertheless, skin symptoms recurred immediately after dexamethasone treatment in its original intensity was terminated, even though the concentration of monoclonal immunoglobulin IgA remained below the sensitivity of quantitative detection for further 6 months (positive immunofixation only). Six rituximab 600 mg infusions were administered in a weekly interval after stopping cyclophosphamide and dexamethasone to prevent early recurrence of skin symptoms but this treatment was without any lasting effect. Transformation into multiple myeloma was identified in 2007. First line treatment (cyclophosphamide, adriamycin and dexamethasone - CAD) remained without any haematological or dermatological treatment response. Second line treatment (thalidomide, cyclophosphamide and dexamethasone - CTD) brought about significant deterioration of skin symptoms up to the clinical picture of erythrodermia. Third line treatment (bortezomib 1.3 mg/sqm i.v. on days 1,4, 8 and 15, cyclophosphamide 50 mg daily and dexamethasone 20 mg on days 1-4 and 15-18 in 28-day cycles - VCD) resulted in rapid decline in monoclonal immunoglobulin IgA concentrations immediately following the first cycle and to negative immunofixation after 5 cycles. In total, six VCD cycles were administered. The patient has had no skin symptoms from the third cycle of this treatment and complete skin and haematological remission has been maintained for 12 months after completion of bortezomib-containing treatment. Combined treatment containing bortezomib has proven useful in the treatment of IgA pemphigus accompanying monoclonal gammopathy of uncertain significance transformed into multiple myeloma.