Generalized pustular psoriasis following withdrawal of oral cyclosporin treatment for palmo-plantar pustulosis

We report the cases of two patients who developed generalized pustular psoriasis on the withdrawal of oral Cyclosporin treatment for persistent palmoplantar pustulosis. This complication does not appear to have been reported previously.     

Neutrophil and monocyte chemotaxis in pustulosis palmo-plantaris and pustular psoriasis

Polymorphonuclear leukocyte (PMN) and monocyte (MN) chemotaxis in nine patients with pustulosis palmo-plantaris (PPP) and ten patients with pustular psoriasis (PP) was determined by an objective in vitro assay employing a 51Cr-labelling technique. PMN chemotaxis was significantly enhanced in both groups of patients compared with controls. MN chemotaxis was normal. There was no difference in the chemotactic responsiveness of leukocytes from patients with PPP and PP. The random migration of PMN and MN from the patients was normal. Homogenized tissue specimens from lesional skin with and without pustules, and from perilesional, normal-looking skin of PPP and PP were analysed for the presence of chemoattractant(s) for PMN. Lesional skin had considerable chemoattractant properties, but perilesional skin did not induce directed migration of PMNs.     

Serum lipid changes during acitretin (etretin) treatment of psoriasis and palmo-plantar pustulosis

The effects of acitretin (free acid of etretinate) on the serum lipoprotein pattern and on the fat elimination in serum of 8 patients with psoriasis and 4 with palmo-plantar pustulosis were studied. The drug was given for 12 weeks; the average daily dose was 40 mg. Lipoprotein analyses and an intravenous fat tolerance test (IVFTT) were performed on three occasions (before, after 8 weeks' treatment, as well as 8 weeks after the end of the treatment). Acitretin increased the triglyceride concentration of the very low density lipoproteins by about 50% (p less than 0.02) and reduced the cholesterol of the high density lipoproteins significantly (p less than 0.001), leading to an increased low density/high density lipoprotein cholesterol ratio (p less than 0.02). The IVFTT indicated a lowering of the fat elimination capacity. All changes reverted to the original values after an 8-week wash-out period. The data suggest that the effects of acitretin on the lipoprotein metabolism resemble those of etretinate and isotretinoin.     

A comparison of Ki-67 antigen presentation in acute generalized exanthematous pustulosis and pustular psoriasis

Ki-67 is an established marker of cell proliferation. It is highly expressed in psoriasis and correlated with the clinical severity of psoriasis. Higher number of Ki-67 positive keratinocytes has been observed in pustular psoriasis (PP) as compared with psoriasis vulgaris. As for Acute generalized exanthematous pustulosis (AGEP), a distinct disease entity but similar in many aspects of clinicopathologic features to PP, Ki-67 immunostaining presentation has never been investigated before. This study aimed to compare Ki-67 immunostaining presentation between PP and AGEP. By immunohistochemical staining, we compared Ki-67 immunostaining presentation on skin lesions of five patients of AGEP and five age-matched patients of PP. Ki-67 positive keratinocytes were counted and mean values were determined to compare between PP and AGEP. An augmented presence of Ki-67 positive keratinocytes was found in both AGEP and PP and they distributed not only in basal cell layer but in middle or even upper part of epidermis. Statistical analysis using Mann–Whitney U test showed no difference of epidermal proliferation rate between the two groups (P = 0.222). The results showed there was no difference of Ki-67 immunostaining presentation between AGEP and PP. Besides, we found marked increase of Ki-67-positive proliferating keratinocytes in AGEP and suggested that epidermal hyperproliferation may also play an important role in the formation of AGEP. We also discussed the possible pathophysiology of AGEP, possible epidermal architecture changes in AGEP and PP, and found the similarity in pathophysiology of AGEP and PP.     

Levels of proelafin peptides in the sera of the patients with generalized pustular psoriasis and pustulosis palmoplantaris

The levels of proelafin peptides in the sera of patients with pustulosis palmoplantaris, a unique type of localized pustular psoriasis, and generalized pustular psoriasis were determined by competitive enzyme-linked immunosorbent assays using antibodies against synthetic proelafin polypeptides corresponding to the elastase inhibitor (elafin) and transglutaminase substrate domains. The sera of patients with pustulosis palmoplantaris (9 cases) exhibited a normal range of proelafin peptide levels. The sera of patients with generalized pustular psoriasis (3 cases) showed high titres of proelafin peptide. There were no large differences in the titres between the 2 antibodies. The antibodies for 2 different domains of proelafin showed a similar immunoreactivity for the non-pustular region of the epidermis in all pustulosis palmoplantaris tested. The results indicate that serum proelafin peptides in pustular psoriasis may depend on the extent of the involved area, and that proelafin peptide level in pustulosis palmoplantaris remains normal despite enhanced local expression in the lesional skin. Since the skin lesions of patients with pustulosis palmoplantaris are limited to the palms and soles, enhanced expression of proelafin in the lesional skin may not lead to elevation of proelafin peptides in the serum.     

A diagnostic challenge: acute generalized exanthematous pustulosis or pustular psoriasis due to terbinafine

A 72-year-old man developed a generalized erythematous pustular eruption 11 weeks after commencing terbinafine. Clinically and histologically, the appearance was that of acute generalized exanthematous pustulosis (AGEP), and the disease was managed with topical preparations. Initial improvement was marred by relapse of acute pustulosis, now more in keeping with terbinafine-induced pustular psoriasis (PP), which was successfully treated with acitretin. This case highlights the difficulty of differentiating between AGEP and PP.     

Chronic subcorneal pustulosis with vasculitis: a variant of generalized pustular psoriasis in black South Africans

A rare, but distinctive chronic eruption in six female black South Africans is reported. The original diagnosis of subcorneal pustular dermatosis of Sneddon and Wilkinson in these patients was refuted by the subsequent histological observation of both spongiform pustules and an underlying vasculitis. This may represent a previously undocumented form of generalized pustular psoriasis.     

Animal models of psoriasis and pustular psoriasis

Investigation of psoriasis and pustular psoriasis is presently hampered by the lack of appropriate animal models. So far, more than ten models have been developed in mice by spontaneous gene mutations and by gene manipulation. However, none of them has satisfactorily reproduced the clinicopathological and immunopathological phenotypes of these diseases. Xenotransplantation techniques have been used for designing models of psoriasis vulgaris, in which CD4(+) T cells have been shown to play an important role. An ideal model for pustular psoriasis should have an immunological background and fulfill the diagnostic criteria of psoriasis.     

A Crohn's disease-associated insertion polymorphism (3020insC) in the NOD2 gene is not associated with psoriasis vulgaris,palmo-plantar pustular psoriasis or guttate psoriasis

A C-insertion polymorphism in the NOD2 gene (3020insC) on chromosome 16 is a rare mutation associated with Crohn's disease. Crohn's disease and psoriasis are more commonly observed together than expected by chance. Furthermore a susceptibility locus for psoriasis has been identified on chromosome 16q which overlaps the recently identified susceptibility locus for Crohn's disease. Thus, NOD2 may potentially be important as a candidate susceptibility gene for psoriasis. We tested this hypothesis by genotyping psoriasis patients for the C-insertion polymorphism using the Taqman ABI 7700 sequencing system. No statistically significant differences were observed between psoriasis vulgaris (n = 216), palmo-plantar pustular psoriasis (PPP) (n = 100), guttate psoriasis (n = 118) and the control group (n = 283). In both patient and control groups, no mutant homozygotes were observed and approximately 4% were heterozygotes. This particular insertion mutation in the NOD2 gene does not appear to contribute to the genetic susceptibility of psoriasis vulgaris, PPP or guttate psoriasis. However, other mutations exist in the NOD2 gene, which may potentially have a role in psoriasis susceptibility.     

Colchicine in generalized pustular psoriasis: Clinical response and antibody-dependent cytotoxicity by monocytes and neutrophils

Summary Four patients with generalized pustular psoriasis were treated with oral colchicine in an open study. Three of the four patients went into total remission within two weeks while receiving colchicine. The monocyte- and neutrophil function was assessed by studying antibody-dependent cytotoxicity. Increased values observed before treatment decreased during treatment. The patient who responded poorest clinically also showed less changes in monocyte- and neutrophil antibody-dependent cytotoxicity.