Curious Case of Photo-distributed Verrucae in a Renal Transplant Patient: Report of Three Cases.

Viral warts are a common lesion found in patients who have undergone a renal transplant. The occurrence of verrucae also depends on the choice of immunosuppressant and posttransplant time interval. The presence of viral warts only on sun-exposed parts of the body is extremely uncommon and rarely reported. It might also influence the choice of treatment since these warts are often resistant to treatment.

What was known?

Viral warts are commonly seen in renal transplant patients on immunosuppressive therapy. Photodynamic therapy is often used as a treatment for recalcitrant warts.

Introduction

Infectious diseases are the most commonly seen dermatoses in posttransplant patients. They are mostly of viral or fungal etiology. They are often resistant to treatment and a precursor to the development of cutaneous malignancy subsequently especially on infections with high-risk human papillomavirus (HPV) types. Cutaneous verruca may be one of the presentations but extremely uncommon is the presentation in the photo-distributed areas and after an extensive search of medical literature we found hardly a few cases have been reported worldwide.

Case Reports

Case 1

A 50-year-old man, who was a footballer by profession, presented to the Dermatology Outpatient Department with complaints of unsightly raised skin lesions all over his body for the last 2–3 years which were progressively increasing in size and number. He had undergone renal transplant around 10 years back and had been taking azathioprine continuously for several years which had only recently been stopped. He had no other complaints and was in good health otherwise. He had tried some topical treatments but had not got any beneficial effect.

On examination, he had multiple lesions varying in size from 0.5 to 1.5 cm all over his body. The lesions were flat, filiform to dome shaped with a verrucous surface. Some of the lesions were of normal skin color while others were hyperpigmented. They were present over the face and neck extending only till the V-area of the upper chest [Figure 1], the bald area on the scalp, the dorsa of forearms and hands, and dorsa of feet and lower leg [Figure 2].

Figure 1

Multiple warts of varying sizes involving the photo-exposed parts of the upper body - the face, V-area of the neck, and sides of the face of a 50-year-old male patient

Figure 2

Multiple warts involving the bald area of the scalp, dorsa of both hands and feet in the same 50-year-old male patient

Case 2

A 45-year-old married female presented with multiple warty hyperpigmented lesions over the V area of the neck, lower arm (right arm involved more than the left) [Figure 3]. There was characteristic sparing of the areas which are covered by saree in Indian females, thus further accentuating the characteristic photodistribution. She had undergone renal transplant around 8 years back and had been prescribed azathioprine which she was continuing.

Figure 3

Multiple warts of varying sizes involving the sun-exposed sites, the V-area of the neck, and arms with characteristic sparing of the areas covered by “pallu” of the saree in a 45-year-old female patient

Case 3

A 63-year-old man presented with complaints of multiple hyperpigmented warty lesions over the sun-exposed parts of the body mainly on the V-area of the neck, the dorsa of hands and upper arms [Figure 4]. He was a shop owner and spent most of his time indoor, thus the lesions limited to the sites of the body which are most commonly exposed to the sunlight.

Figure 4

A 65-year-old male patient with multiple warts of varying sizes involving mainly the V-area of the neck and dorsa of both hands which are commonly exposed to the sun with sparing of other sun-exposed parts due his occupation which involved staying indoors

He had undergone renal transplant over 15 years back and was not taking any immunosuppressive medication at present.

The most striking feature of these lesions in all these patients was the sharp demarcation between the sun-exposed and normal skin. The lesions were characteristically distributed over the sun-exposed parts of the body and followed the lines of demarcation where the skin was covered with clothes. The covered parts of the body had very few lesions in comparison. The mucosal surfaces were also spared.

A provisional clinical diagnosis of actinic keratosis and viral warts was made and tissue samples from the most characteristic lesions were sent for histopathologic examination for confirmation. In all the three cases, it revealed characteristic features of verruca vulgaris. There was hyperkeratosis with papillomatosis, large keratohyalin granules, and characteristic inward turning of the rete ridges. Parakeratotic columns of stratum corneum were also seen overlying the papillomatous surface. Few koilocytes were also seen [Figure 5]. Thus, the diagnosis of actinic keratosis was ruled out. The clinical and histopathological features confirmed the diagnosis of viral warts. The patient was prescribed cryotherapy and asked to come for regular follow-ups for the same.

Figure 5

Histopathology images showing hyperkeratosis with papillomatosis, large keratohyalin granules and characteristic inward turning of the rete ridges. Parakeratotic columns of stratum corneum were also seen overlying the papillomatous surface. Few koilocytes were also seen (a: H and E, ×40 and b: H and E, ×100)

Discussion

Verruca vulgaris is one of the important dermatoses seen in postrenal transplant patients. Kidney transplant recipients have a 15–50% likelihood of developing common warts associated with the HPV in the 1st year following the transplant and a 77–95% likelihood within 5 years.[1]

In various studies from India, the prevalence of warts in renal transplant patients has been shown to vary from 8% to 55%.[23456789]

In a study by Sulowicz et al., it has been shown that older age, male sex, and longer duration of immunosuppressive therapy are risk factors for the development of viral warts in patients after kidney transplantation. Cyclosporine A and azathioprine also lead to the development of infectious viral warts.[10]

In a study by Dicle et al., it was seen that azathioprine when given in any combination, increased the risk of patients developing HPV infection.[11]

A possible explanation for increased incidence of viral warts in transplant patients is likely the immunosuppression due to high levels of circulating uric acid. However, the likely explanation for the occurrence of warts over the sun-exposed parts of the body could be a selective immunosuppression by the ultraviolet spectrum of light. Immunosuppressive therapy thus has a likely additive effect which increases the risk of acquiring viral warts.

Actinic keratosis is an important differential as they can subsequently lead to cutaneous malignancies. It is thus important to follow-up these patients periodically for early diagnosis of the same.

Viral warts can be seen on any part of the body and commonly on exposed parts. However, in our patients, the lesions were mainly distributed over the sun-exposed parts of the body with clear cut demarcation line, especially on the front of the chest. This is a curious and highly uncommon presentation and likely due to the additive effect of long-term immunosuppressive therapy with azathioprine and sun exposure.

In transplant patients, warts are often recalcitrant to treatment and photodynamic therapy has been used with good results.[12] However, this may worsen the lesions in patients who have lesions in sun-exposed parts of the body like ours and alternative treatments must be considered. Moreover, these patients may also be prone to developing actinic keratosis and cutaneous malignancies in the future because of the nature of their lesions and thus need to be carefully followed up.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

What is new?

This is a very uncommon and curious presentation of viral warts on the sun-exposed parts of the body in a renal transplant patient. The combined immunosuppressive effect of medications and sunlight can cause warts to occur in photo-distributed sites. Chance of infection with high-risk type of human papillomavirus is also a possibility. The treatment modality must be carefully chosen for these patients along with regular follow-up for early identification of any malignancy.