Synonyms: localised pustular psoriasis

Palmoplantar pustulosis (PPP) is a chronic inflammatory skin condition, which typically presents as multiple sterile pustules on the palms and soles (initially yellowish fading to brown macular pinpoint lesions). It is considered by some to be a variation of psoriasis and occurs in patients with other types of psoriasis.¹ However, the nature of the link with psoriasis is unclear and there are significant differences. Neuroendocrine dysfunction of the sweat glands has been implicated in the pathogenesis.²

Epidemiology

The condition occurs much more commonly in smokers and ex-smokers. It may run in families and rarely occurs in childhood. Gluten sensitivity and tonsillar streptococcal infection have been implicated in some cases.³

Differential diagnosis

• Infected eczema - less defined, white vesicles rather than pustules, swabs often grow Staphylococcus aureus. Acute pompholyx is an episodic form of eczema affecting the palms and soles with bullae formation, which frequently becomes infected.
• Tinea pedis - commonly unilateral or asymmetrical erythema, scaling and pustules. Toe clefts and nails are usually involved.
• Reiter's disease - gross palmar and plantar lesions may occur (keratoderma blennorrhagica) which are histologically indistinguishable from psoriasis. This also affects the mouth and penis.
• Acrodermatitis continua of Hallopeau (ACH): a rare indolent form of psoriasis with sterile pustular changes and dactylitis affecting the distal digits and nails.⁴

Primary care management^1,5,6

Evidence-based treatment for palmoplantar pustulosis (PPP) is contentious. Those who claim that PPP is simply a variation of psoriasis believe that the condition should be managed as per the guidelines for psoriasis but there is no consensus on this.² Various treatments have been used but none is generally accepted as universally effective.³ A Cochrane Review highlighted methodological problems with the studies designed to differentiate between the efficacy of different approaches.⁷

Within primary care:

• Encourage general measures:
  • Good footwear made from natural fibres.
  • Avoidance of even minor trauma.
  • Waterproof dressings over fissured areas.
  • Rest the affected area where possible.
• Emollients are important:
  • Apply thick greasy emollients to soften skin and prevent fissures.
  • Soak in warm water with emulsifying ointment.
  • Use salicylic acid ointment or urea cream to peel dead skin.
  • Wash with soap substitutes.
• Potent topical steroid ointments, e.g. clobetasol propionate, may be used twice daily for limited periods. High-potency steroids are required in order to penetrate the thick skin of the hands and feet. Occlusion with clingfilm or dressings can enhance penetration but should not be used for more than five days in a row.
• Coal tar is messy but can be applied directly, often mixed into an ointment base.
• Calcipotriol can be helpful - apply twice a day and do not cover.

When to refer^1,5

Referral is primarily for help with diagnosis and treatment, or if symptoms are particularly disabling.

Palms and soles are difficult sites to treat and palmar pustular psoriasis can be resistant to treatment so specialist advice may be required.

Further treatment options which dermatologists can use include:

• Systemic retinoids - for example, acitretin, arotinoid ethyl ester.⁸
• Psoralen combined with ultraviolet A (UVA) treatment (PUVA) to hands and feet (sometimes combined with systemic retinoids).⁷
• Methotrexate.¹
• Etanercept.⁹

Complications

• Pain from lesions and associated fissuring may be significant.
• Walking and standing for long periods can exacerbate lesions on the soles of the feet.
• Manual activity can be uncomfortable if the hands are affected.
• Occupational and functional disability secondary to above.
• Pustulotic arthro-osteitis (sterile inflammatory osteitis of the sternoclavicular region) is a rare but severe complication of palmar pustulosis.¹⁰

Prognosis

The condition tends to be chronic and poorly responsive to treatment.¹

Document references

1. Palmoplantar Pustulosis, DermNet NZ
2. de Waal AC, van de Kerkhof PC; Pustulosis palmoplantaris is a disease distinct from psoriasis. J Dermatolog Treat. 2011 Apr;22(2):102-5. Epub 2010 Aug 5. [abstract]
3. Mrowietz U, van de Kerkhof PC; Management of palmoplantar pustulosis: do we need to change? Br J Dermatol. 2011 May;164(5):942-6. doi: 10.1111/j.1365-2133.2011.10233.x. [abstract]
4. Bordignon M, Zattra E, Albertin C, et al; Successful treatment of a 9-year-old boy affected by acrodermatitis continua of Photodermatol Photoimmunol Photomed. 2010 Feb;26(1):41-3. [abstract]
5. Psoriasis - General Management, British Association of Dermatologists (2008)
6. Diagnosis and management of psoriasis and psoriatic arthritis in adults, Scottish Intercollegiate Guidelines Network (SIGN), October 2010
7. Marsland AM, Chalmers RJ, Hollis S, et al; Interventions for chronic palmoplantar pustulosis. Cochrane Database Syst Rev. 2006 Jan 25;(1):CD001433. [abstract]
8. SHAN SJ, LI YH, ZHANG G, et al; Treatment of palmoplantar pustulosis with arotinoid ethylester. Eur J Dermatol. 2009 Sep-Oct;19(5):474-7. Epub 2009 Jun 5. [abstract]
9. Bissonnette R, Poulin Y, Bolduc C, et al; Etanercept in the treatment of palmoplantar pustulosis. J Drugs Dermatol. 2008 Oct;7(10):940-6. [abstract]
10. Hayama K, Inadomi T, Fujisawa D, et al; A pilot study of medium-dose cyclosporine for the treatment of palmoplantar Eur J Dermatol. 2010 Nov-Dec;20(6):758-62. Epub 2010 Nov 4. [abstract]

Internet and further reading

• Pustular Psoriasis of the Palms and Soles, DermIS (Dermatology Information System)
• Pustular Psoriasis, Psoriasis Association
• Chang L, Ubriani R, Yan AC; Picture of the month--quiz case. Pustular psoriasis, annular type. Arch Pediatr Adolesc Med. 2008 Oct;162(10):989-90.

Acknowledgements