Case study
A 32-year-old mechanic presented with a three-year history of intense itching and rash to both the palmar aspects of his hands. The rash periodically improved, usually when he went on holiday. Initially, his symptoms were mild and intermittent, but they had become more persistent and troublesome.
The patient found that wearing gloves at work sometimes helped because this meant he needed to wash his hands less frequently.
He felt his symptoms were significantly affecting his work and his sleep was also being disrupted. He had been prescribed various creams over the past two years, which had not appeared to help.
On examination, there was a rash to both palmar aspects of his hands. Both hands were dry, with scaly skin and a few vesicles. There was evidence of fissuring, lichenification and poorly demarcated erythema. A few excoriations were visible.
Differential diagnoses include irritant contact dermatitis and allergic contact dermatitis. Allergic contact dermatitis may arise several hours after contact with an allergen - in this case, there was probably exposure to multiple allergens.
Irritant contact dermatitis may have similar symptoms, but is caused by excessive contact with irritants, such as soap and solvents. It tends to occur more often in those with atopic dermatitis.
After advising the patient about possible causative factors, I explained that keeping his nails short and, if possible, avoiding irritants and wet work would be helpful. Wearing vinyl gloves at work might help, but these should not be worn for long, because they may exacerbate symptoms due to sweating.
I prescribed emollients to be used regularly and as a soap substitute. Greasier preparations are more effective, but can make working more difficult. The patient opted to use a greasier emollient at night. I also prescribed a potent topical steroid.
Irritant contact dermatitis was the more likely diagnosis, so I did not consider patch testing.
Review one week later indicated significant improvement. We decided to step down topical corticosteroid use and I advised him about long-term emollient therapy.
Discussion
Contact dermatitis may account for up to 7% of dermatological consultations.1 Allergic contact dermatitis involves an allergen causing dermatitis or exacerbating existing dermatitis through sensitisation.1
Irritant contact dermatitis is more common than allergic dermatitis and the latter tends to have a worse prognosis, particularly if it has not been possible to identify the allergen.1
The condition is largely managed by avoiding contact with irritants, such as soap; there may be more specific irritants, depending on the patient's occupation. Wet work may also be a factor.1
Patients with steroid-resistant contact dermatitis should be referred.2 Those with occupational contact dermatitis may need to see an occupational health specialist.
- Dr Kochhar is a GP principal in Bexhill, East Sussex
References
1. Bourke J, Coulson I, English J. Br J Dermatol 2009; 160: 946-54.
2. Royal College of Physicians. Diagnosis, management and prevention of occupational contact dermatitis. London, RCP, 2011.
