760 Correspondence In renal graft recipients, the incidence of porokeratosis varies between 0.34 and 10.68%. 1 Disseminated superficial porokeratosis or punctuate porokeratosis are prevalent forms in organ-transplant recipients, but giant porokeratosis is very rare. Systemic immunosuppression is a well-documented trigger in genetically predisposed skin. In the patients here reported, immunosuppressive regimens included corticoids, cyclosporine, azathioprine, and tacrolimus. There is no evidence to suggest that any of the commonly used immuno- suppressive drugs is more likely to induce the development of porokeratosis than another. Complete regression has been reported after discontinuation of immunosuppressive treatment. 2 One of the patients had chronic HCV infection, a condition also found associated with porokeratosis. Our two patients developed hyperkeratotic lesions on the porokeratosis plaques. The first patient had a squamous cell carcinoma that was totally excised. In some cases, the porokeratosis lesions may undergo malignant transformation to Bowen’s disease, squamous cell carcinoma, 3 basal cell car- cinoma (more rarely), or melanoma. The risk of malignant degeneration increases with the size of the lesion and the patient’s age. Our patient was older than 60 years and had a large (6 × 6 cm) porokeratosis lesion. The second patient developed a verrucous lesion. Warty nodules on an annular plaque in a renal transplant recipient have been reported, which were concordant with viral warts, as in our case. 4 Although HPV testing gave negative results, the fact that HPV type 6 was detected in the first patient supports the suspicion that HPV may be involved in the appearance of superimposed hyperkeratotic lesion on porokeratosis in immunosuppressed patients. María Pérez-Crespo, MD Isabel Betlloch Ana Lucas-Costa José Bañuls-Roca María Niveiro de Jaime Javier Mataix Department of Dermatology and Department of Pathology, Hospital General Universitario de Alicante, Alicante, Spain Conflicts of interest: Not declared. Funding: None. References 1 Herranz P, Pizarro A, De Lucas R, et al. High incidence of porokeratosis in renal transplant recipients. Br J Dermatol 1997; 136: 176 – 179. 2 Kanitakis J, Euvrard S, Faure M, et al. Porokeratosis and immunosuppression. Eur J Dermatol 1998; 8: 459 – 465. 3 Lin JH, Hsu MM, Sheu HM, et al. Coexistence of three variants of porokeratosis with multiple squamous cell carcinomas arising from lesions of giant hyperkeratotic porokeratosis. J Eur Acad Dermatol Venereol 2006; 20: 621 – 623. 4 Theng CT, Yosipovitch G. Warty nodules on an annular plaque in a renal transplant recipient. Arch Dermatol 2004; 140: 121 – 126. Correspondence Atypical petechial rash of the lower extremities due to Parvovirus B19 infection Patients with Parvo B19 infection usually undergo a subclinical course but sometimes suffer non specific symptoms like fever, arthralgias and myalgias. Parvo B19 is also considered respon- sible for “papular purpuric gloves and socks syndrome” (PPGSS). Recently, another clinical entity named “acropetechial syn- drome” was described. In this case, the typical PPGSS syndrome is combined with perioral involvement. We report a case of a 71 year-old-lady who presented with generalized arthralgias and purpuric rash (Fig. 1) of the lower extremities from the hip joints down to the ankles sparing the Figure 2 (a) Plaque of porokeratosis on the dorsal aspect of the left hand with a hyperkeratotic tumor in one of the margins. (b) Papillomatous and hyperkeratotic epidermis with cytopathic changes in some keratinocytes and subcorneal erythrocytes, consistent with a viral wart (H&E, ×40) International Journal of Dermatology 2008, 47, 760–762 © 2008 The International Society of Dermatology