Causes and features of erythroderma.

Introduction: Erythroderma is a generalised inflammatory reaction of the skin secondary to a variety of causes. This retrospective study aims to characterise the features of erythroderma and identify the associated causes of this condition in our population.

Materials And Methods: We reviewed the clinical, laboratory, histological and other disease-specific investigations of 225 inpatients and outpatients with erythroderma over a 7.5-year period between January 2005 and June 2012.

Results: The most common causative factors were underlying dermatoses (68.9%), idiopathic causes (14.2%), drug reactions (10.7%), and malignancies (4.0%). When drugs and underlying dermatoses were excluded, malignancy-associated cases constituted 19.6% of the cases. Fifty-five percent of malignancies were solid-organ malignancies, which is much higher than those previously reported (0.0% to 25%). Endogenous eczema was the most common dermatoses (69.0%), while traditional medications (20.8%) and anti-tuberculous medications (16.7%) were commonly implicated drugs. In patients with cutaneous T-cell lymphoma (CTCL), skin biopsy was suggestive or diagnostic in all cases. A total of 52.4% of patients with drug-related erythroderma had eosinophilia on skin biopsy. Electrolyte abnormalities and renal impairment were seen in 26.2% and 16.9% of patients respectively. Relapse rate at 1-year was 17.8%, with no associated mortality.

Conclusion: Our study highlights the significant proportion of malignancy-related erythroderma in those whom common underlying causes such as dermatoses and drugs have been excluded. In cases of drug-related erythroderma, traditional medications and antituberculous medications are common causes in our population. Renal impairment and electrolyte abnormalities are commonly seen and should be monitored in patients with erythroderma.