To the Editor.—
The pathogenesis of psoriasis with or without psoriatic arthropathy is poorly understood. Immunologic phenomena are currently thought to play an important role in the development of these disorders.1 In particular, several studies have demonstrated elevated levels of serum and/or salivary IgA in patients with psoriasis.2,3 The values have been reported to return to normal after therapy.4 We have observed two patients with psoriatic arthropathy associated with selective and complete absence of IgA.
Report of Cases.—Case 1.—
A 27-year-old man had a five-year history of psoriasis involving the scalp, elbows, and knees. There was a two-year history of an asymmetric polyarthritis involving the peripheral joints and axial skeleton. A complete blood cell count and routine blood chemistry results were normal. The ESR was 5 mm/hr. The latex fixation test result was negative, as was an assay for HLA-B27. Quantitative serum immunoglobulin levels measured
Sagransky DM, Greenwald RA. Psoriasis Associated With Selective IgA Deficiency. Arch Dermatol. 1980;116(7):750. doi:10.1001/archderm.1980.01640310020006