Risk of skin cancer in patients on chronic haemodialysis: a nationwide, population-based study in Taiwan.

BACKGROUND: Patients on chronic haemodialysis (HD) have a higher incidence of cancer. However, the risk of skin cancer in this population has rarely been investigated. OBJECTIVES: To investigate the risk of nonmelanoma skin cancer (NMSC) and cutaneous melanoma in patients on chronic HD and to explore the associated risk factors. METHODS: We performed retrospective cohort and nested case-control studies using records in the Taiwanese National Health Insurance Research Database between 1999 and 2013. The HD cohort included 79 668 incident patients on HD, for whom the standardized incidence ratios (SIRs) for incident NMSC and cutaneous melanoma were determined. In the nested case-control study, patients on HD with NMSC were matched to those without skin cancers. The impact of various factors on the development of NMSC was determined by conditional logistic regression analysis. RESULTS: Among the 79 668 patients on HD, 248 cases of NMSC and 22 cases of cutaneous melanoma occurred after a mean 4·95 years of follow-up. The SIRs for NMSC and cutaneous melanoma in patients on HD were 1·58 (95% confidence interval 1·39-1·79) and 1·44 (95% confidence interval 0·91-2·19), respectively. Of the patients on HD, a higher risk of NMSC was found in men (1·5-fold), South Taiwan residents (twofold) and patients with uraemic pruritus after long-term antihistamine treatment (1·53-fold). However, the incidence of NMSC was not increased in patients with uraemic pruritus receiving ultraviolet B phototherapy. CONCLUSIONS: Patients on chronic HD are at higher risk of NMSC. Uraemic pruritus further increases the risk of NMSC, which might be prevented by ultraviolet B phototherapy.

Prostacyclin protects renal tubular cells from gentamicin-induced apoptosis via a PPARalpha-dependent pathway.

To study the protective effect of prostacyclin (PGI2) we increased PGI2 production by infected NRK-52E cells with an adenovirus carrying cyclooxygenase-1 and prostacyclin synthase. PGI2 overexpression protected these cells from gentamicin-induced apoptosis by reducing cleaved caspase-3 and caspase-9, cytochrome c, and decreasing generation of reactive oxygen species. Expression of the nuclear receptor of PGI2, peroxisome proliferator-activated receptor-alpha (PPARalpha), was reduced during gentamicin treatment of the cells, while its overexpression significantly inhibited gentamicin-induced apoptosis and the amount of cleaved caspase-3. Transformation with PPARalpha short interfering RNA abolished the protective effect of PGI2 overproduction in gentamicin-treated cells. The PPARalpha activator docosahexaenoic acid given to gentamicin-treated mice significantly reduced the number of apoptotic cells in renal cortex, but this protective effect was not seen in PPARalpha knockout mice. Our study suggests that increased endogenous PGI2 production protects renal tubular cells from gentamicin-induced apoptosis through a PPARalpha-signaling pathway.

Generalized argyria in two chronic hemodialysis patients.

Silver can be absorbed through ingestion, topical administration, or inhalation. Generalized argyria results from deposition of silver in the skin, nails, mucous membranes, and internal organs and is characterized by a diffuse bluish-gray discoloration in sun-exposed areas. We report two cases of generalized argyria in patients on maintenance hemodialysis (HD) therapy for more than 15 years. They presented with diffuse hyperpigmentation of the face that was mistaken to be related to uremia and bluish-gray discoloration of all nails believed to be cyanosis. Histopathologic examination of skin biopsy specimens showed characteristic findings of argyria, which was further confirmed by radiograph microanalysis. Their serum silver levels were also elevated. No definite silver source could be determined. However, their argyria might be related to their long-term HD therapy because (1) they had been on HD therapy for more than 15 years and the discoloration appeared several years afterward, and (2) the water used for HD was not well processed in the early 1980s in TAIWAN: Argyria should be suspected in chronic HD patients presenting with a diffuse bluish-gray discoloration of the skin and nails and evaluated carefully by skin biopsy.