Discussion:
EV is a rare inherited genodermatosis characterized by an increased
susceptibility to specific genotypes of human papillomaviruses
(HPV).2 HPV 5 and 8 are reported to be the major
causative agents. Causal genetic mutations have been identified in the
EVER genes.3 The etiopathogenesis is multifactorial,
involving viral, genetic and environmental factors. Over time, affected
subjects have an increased risk of squamous cell carcinoma on
sun-exposed areas. In 1983, Lutzner and colleagues had detected, in a
renal-allograft recipient, HPV 5 DNA, in both Squamous cell carcinomas
and benign skin lesions that resemble clinically and histologically to
the lesions of inherited EV. They suggested a synergistic action between
HPV infection, immunosuppression and sunlight exposure in the occurrence
of skin carcinoma in renal-transplant recipient.4Acquired EV is a term coined in 2009 by Rogers and colleagues to
describe acquired phenotypes of EV discovered in HIV
patients.5 Other conditions of suppressed cellular
immunity have been associated with acquired EV such as systemic lupus
erythematosus,6 GVH disease,7 atopic
dermatitis 8 and solid organ transplantation such as
renal transplantation.9 The description of acquired EV
in immunocompromised hosts suggests the potential role of a specific
immune deficiency. A novel classification for the different types of EV
subdivides the disease into genetic EV (classic and non-classic
according to the mutations) and acquired EV.10Although an underlying genetic susceptibility to HPV infection in
immunocompromised patients with acquired EV has been hypothesized, it
has not yet been identified.
Clinically, acquired EV manifests usually with the same features as
genetic EV, namely a tinea versicolor-like eruption of the trunk, face
and extremities and verruca-like lesions on the distal
extremities.2 Published data about acquired EV related
to renal transplantation is scarce with mainly single case reports.
Table 1 shows all reported clinical cases of acquired EV in renal-
transplant recipients. Most cases have a typical
presentation.9,11,12 In other papers, the presentation
was atypical with lesions limited to the perineum 13and the inguinal folds.14 A case of acquired EV
mimicking a periungual malignant melanoma was reported in a patient
diagnosed with a cutaneous T cell lymphoma.15 In our
case, the diagnosis was discovered fortuitously on a biopsy for a drug
reaction suspicion.
As for cancer susceptibility, the progression to non-melanoma skin
cancers in acquired EV has not been well
established.2,5 In organ-transplant recipients, the
use of immunosuppressive medications to prevent organ rejection is
responsible for increasing the susceptibility for viral infections,
particularly HPV, that may explain the occurrence of the acquired EV
phenotypes. In his report, Mendes highlights the role of
post-transplantation immunosuppressive medications in increasing both
the susceptibility for viral infections and the rate of malignancies.
This effect is caused by most of the molecules used.9In the cases of the literature, all renal-transplant recipients were
undergoing maintenance immunosuppressive
therapy.7,9-14 These immunosuppressant molecules are
known to increase the risk of malignancy.16 Similarly
to genetic EV, acquired EV may be associated with a higher rate of
cutaneous cancers. The cumulative effect of these two risks in
renal-transplant recipients is still unknown and an intensification of
the monitoring could be an option. As a precaution, photoprotection is
mandatory.
No effective curative treatment has yet been discovered for neither the
genetic nor the acquired forms.2,5 Several treatment
options have been proposed. However, no modality has been shown to be
consistently successful. A case of an acquired EV in a renal-transplant
recipient that cleared with a multimodal therapy including Gardasil
vaccination has been reported.14