A 13-year-old girl had suffered from eczema since she was 5 years old, when she developed a scaly red rash over her knees and elbows (Fig.1-A, Fig.2-A). Her father had atopic dermatitis, and the family lived in a southern city in China before they immigrated to Singapore. There were no pets, and her parents did not smoke.
The patient’s mother reports that various brown and white creams dispensed by doctors had been applied on her infected lesions during past 5 years. During physical examination the patient was evidently uncomfortable and scratched continuously at her skin. Her mother reports that she scratched the eruptions even while sleeping. Her skin was very dry and red with large scales, displaying scratched and infected lesions on her legs and arms. The patient was advised to avoid hot showers even though the pain produced by hot water is better tolerated than the sensation of itching; however, heat aggravates acute eczema. Meanwhile, she was prescribed Tangs Derma-zema 1440mg three times daily. The patient recovered gradually in a wavelike process which occurred within 30 days after treatment, as shown in Figure.1-B and Figure.2-B.
Thereafter, eczema lesions improved significantly in response to TANGS monotherapy (Fig.1-C, Fig.2-C), together with the use of emollients. During the treatment, no corticosteroid cream was given. Eczema can be provoked by sudden withdrawal of steroid or immunosuppressive drugs: the body will experience a rebound phenomena, which can include inflammatory reactions such as the swelling of joints; allergic responses; feverishness; and discharge from the skin. At the end of month 8, the eczema lesions were completely cleared (Fig.1-D, Fig.2-D).
- Skin Barrier Disruption
Decrease of skin barrier function associated with reduced ceramide levels and increased transepidermal water loss by frequent bathing and hand washing. Dehydration is an important exacerbating factor.
Staphylococcus aureus is almost always present in severe cases; honey-colored crusting, folliculitis, and pyoderma are indicators of secondary bacterial skin infection. Superficial fungal infections are also more common in atopic individuals, and may contribute to the exacerbation of AD. Patients with AD have an increased prevalence of Trichophyton rubrum infections compared to non-atopic controls. There has been particular interest in the role of M. furfur (Pityrosporum ovale or P. orbiculare) in AD. M. furfur is a lipophilic yeast commonly present in the seborrheic areas of the skin. IgE antibodies against M. furfur are commonly found in AD patients and most frequently in patients with head and neck dermatitis. Positive allergen patch test reactions to this yeast have also been demonstrated. The potential importance of M. furfur as well as other dermatophyte infections is further supported by the reduction of AD skin severity in such patients after treatment with antifungal agents.
Placebo-controlled, food challenge studies have demonstrated that food allergens can induce eczematoid skin rashes in nearly 40% of children with moderate to severe AD. In a subset of these patients, urticarial reactions, or non-cutaneous symptoms, are elicited, which can trigger the itch-scratch cycle that flares this skin condition. Children with food allergies generally have positive immediate skin tests or serum IgE directed to various foods, particularly eggs, milk, wheat, soy, and peanuts. After the age of 3, children frequently outgrow their food allergy but may become sensitized to inhalant allergens. Pruritus and skin lesions can develop after intranasal or bronchial inhalation challenge with aeroallergens in sensitized AD patients. Epicutaneous application of aeroallergens (eg., house dust mites, weeds, animal danders, and molds) by atopy patch test on uninvolved skin of AD patients elicits eczematoid reactions in 30–50% of patients with AD. A combination of effective HDM-reduction measures has been reported to improve AD. The degree of IgE sensitization to aeroallergens is directly associated with the severity of AD. The isolation from AD skin lesions and allergen patch test sites of T cells that selectively respond to Dermatophagoides pteronyssinus and other aeroallergens, supports the concept that immune responses in AD skin can be elicited by environmental aeroallergens.
- General Factors
In temperate climates, AD usually improves in summer, and flares up in winter. Pruritus flares after clothing is removed. Wool clothing or blankets directly in contact with the skin are an important trigger. Emotional stress results from the disease, or is itself an exacerbating factor in flareups of the disease.