Paraneoplastic pemphigus (PNP) is a distinct autoimmune blistering disease that can affect multiple organs other than the skin. It occurs in association with certain neoplasms, among which lymphoproliferative diseases are most commonly associated. The clinical presentation of PNP consists typically of painful, severe oral erosions that may be accompanied by a generalised cutaneous eruption and systemic involvement. The eruption may be of different morphology, consisting of lesions that resemble pemphigus, pemphigoid, erythema multiforme or graft versus host disease, as well as lesions resembling lichen planus. Similarly, the histological findings also show considerable variability. PNP is characterised by the presence of autoantibodies against various antigens: desmoplakin I (250 kd), bullous pemphigoid antigen I (230 kd), desmoplakin II (210 kd), envoplakin (210 kd), periplakin (190 kd), plectin (500 kd) and a 170-kd protein. This 170-kd protein has recently been identified as alpha-2-macroglobulin-like-1, a broad range protease inhibitor expressed in stratified epithelia and other tissue damaged in PNP. The prognosis of PNP is poor and the disease is often fatal. Immunosuppressive agents are often required to decrease blistering, and treating the underlying malignancy with chemotherapy may control autoantibody production. The prognosis is better when PNP is associated with benign tumours and these should be surgically excised when possible.

The DC-HIL/syndecan-4 pathway inhibits human allogeneic T-cell responses. Eur J Immunol 2009;39:965e74.

Aquagenic pruritus (AP) is a rare condition with unknown pathogenesis. We explored its pathogenesis through investigations of a patient and report the first case to be effectively treated with atenolol. A 36-year-old Indian female presented with idiopathic AP. Small-fiber neuropathy involving itch/pain-transmitting C-fibers appears to be pathogenetically important: compared with matched controls, our patient had increased intra-epidermal nerve fibers, raised warmth detection threshold, and marked hyperknesis to electrical stimulation. Autonomic nerve function tests and fingertips vasoconstriction response were normal, indicating integrity of other small (Aδ and C) nerve fibers. She was initially treated with propranolol with good response, but was subsequently switched to atenolol for convenient once-a-day dosing. Symptoms were well controlled long term with no side effect experienced. Atenolol may exert its effect in AP through blockage of over-activated neuronal sodium channels. Through the investigations, we propose that the pathogenesis of idiopathic AP may involve the following: upon contact of the skin with water, yet-unknown mediator/s released stimulate dysfunctional and hyper-innervated C-nerve fibers, which may have resulted from a sodium channel defect. Atenolol may be a preferred therapeutic option compared with propanolol, in view of its convenient once-a-day dosing and better side effect profile.

Generalised pruritus and acquired perforating dermatosis occurring in chronic kidney disease are not uncommon and are often debilitating. However, treatment options are limited. We present two patients with uremic pruritus and acquired perforating dermatosis who were successfully treated with amitriptyline.

No abstract