Palmoplantar pustulosis with fulminant dystrophic 20-nail psoriasis in a patient receiving adalimumab therapy.

To the Editor: We report a case of new onset palmoplantar pustulosis and fulminant twenty nail psoriasis in a patient receiving adalimumab treatment for Crohn's disease. A 51 year old woman with a three year history of Crohn's disease well controlled on adalimumab therapy for one year presented for evaluation of a pruritic and painful rash on the palms and soles present one month. There was no family history of psoriasis. On physical exam, bilateral palms and soles revealed erythema, scale, hyperkeratosis, and vesicles without pustules. There was no pitting, onycholysis, or dystrophy of the nails. Since a KOH test from the palms and soles and fungal culture to rule out tinea pedis with a vesicular id reaction were negative, she was prescribed potent topical corticosteriods. After one month, she had new findings of twenty periungal edema, erythema, scale, distorted cuticles, and inflamed proximal nail fold (Fig 1,​,2). 2). The diagnosis of palmoplantar pustulosis with fulminant nail psoriasis was made. The patient refused skin and nail biopsies. Given the association of palmoplantar pustulosis with adalimumab, the patient was asked to discontinue adalimumab and was treated with potent topical corticosteroids to both the skin and nails. Two months later off adalimumab despite topical corticosteroids, she continued to progress with increased palmoplantar pustules, more intense twenty nail proximal nail fold edema and nail plate pitting, and eventually onycholysis (Fig 3,​,4). 4). She went on to develop psoriatic patches over her body and substantially thicker, hyperkeratotic nails. Approximately one month later or three months off drug, she began to improve with less nail swelling, pain, and redness as well as improvement of her skin findings. No systemic intervention was added. She presented to clinic six months after her initial presentation with proximal nail clearing and resolution of her paronychia. (Fig 5,​,6). 6). She also had near complete clearing of her palms. (Fig. 7) Figure 1 Palmoplantar pustulosis. Multiple pustules over the palms with scaling and erythema. Figure 2 Nail Psoriasis. Periungal edema, erythema, scale, distorted cuticles, and inflamed proximal nail folds. Figure 3 Nail psoriasis and paronychia – worse. Intense twenty nail proximal nail fold edema with nail plate pitting and onycholysis Figure 4 Nail psoriasis and paronychia – worse. Intense twenty nail proximal nail fold edema with nail plate pitting and onycholysis Figure 5 Nail Psoriasis – improved. Proximal nail clearing and resolution of her paronychia. Figure 6 Nail Psoriasis – improved. Proximal nail clearing and resolution of her paronychia. Figure 7 Palmoplantar pustulosis – resolved. Despite the successful use of TNF-alpha inhibitors for treatment of psoriasis, previous reports have associated therapy with de novo paradoxical development of psoriasis, specifically palmoplantar pustulosis, in patients obtaining treatment for unrelated conditions.1 Onset of symptoms has no distinct correlation to duration of treatment, ranging from days to years following initiation of therapy. Although the mechanism has not been elucidated, it is believed to be a class effect rather than specific to one agent. 2 It is unclear why palmoplantar pustulosis is so prominently represented among the reported cases of psoriasis developing secondary to TNF-alpha inhibitor therapy.1 To date, there have been several reported cases of palmoplantar pustulosis with nail changes. However, our patient represents an extraordinary example of fulminant nail psoriasis with proximal nail fold edema and nail dystrophy. Our patient was not on any medication associated with paronychia.4,5,6 Current hypotheses suggest the blockage of T-cell activation via the TNF pathway may activate alternate dysfunctional pathways leading to distinct cutaneous manifestations.2,7 Other authors have found an increased expression of Type I interferons in patients on anti-TNF alpha therapy, suggesting a new model of drug reaction.3 The benefit of discontinuing therapy may vary and will require further studies to make conclusive recommendations regarding treatment and outcome.1 Explosive psoriasis involving hands and feet can begin with erythema and edema of the proximal nail fold with pitting and substantial hyperkeratosis of the proximal nail plate. The TNF induced flare of psoriasis is not well understood. Clinicians should maintain a high index of suspicion for psoriasis in patients presenting for new rash while on TNF-alpha blocker therapy and be aware of the varied possible presentations.