K L Gebhard | PubMed Health

PubMed2004

Artificial disruption of skin barrier prior to irritant patch testing does not improve test design.

BACKGROUND: Irritant patch testing is often performed as a 24- or 48-h occlusive patch test with low concentrations of sodium lauryl sulphate (SLS). OBJECTIVES: The aim of this study was to investigate potential ways to shorten this test procedure and obtain precise test results. PATIENTS AND METHODS: Thirty-six healthy volunteers underwent irritant patch testing with different pretreatments (PT) of the test fields. Occlusive test chambers were applied on the upper back with SLS 0.5%, 1%, 2% and 5% in large Finn Chambers(R). The patches were removed after 4 and 24 h, respectively, depending on the concentration used. Test fields were pretreated as follows: PT 0, field without any PT (control); PT 1, prick with lancet; PT 2, prick with test stamp; PT 3, scratch with lancet; PT 4, incision with standardized incision instrument (0.1-0.2 mm depth). Skin reactions were evaluated by transepidermal water loss (TEWL), skin erythema and skin hydration and as well by a visual score (VS) at 4, 24 and 72 h. RESULTS: Our data show an obvious distinction between PT 0-2 and PT 3-4 at all measurement methods. The average TEWL values with PT 3-4 were higher than those with PT 0-2, especially on the 4-h course. This distinction may derive from the shape and size of the skin impairment achieved by PT 3-4, leading to a mechanical barrier disruption. However, SLS may infiltrate directly into deeper skin layers supported by capillarity. Consequently, no or little penetration through the epidermis and interaction with its structures occurs, which is responsible for irritant skin reactions. The SLS dose in the upper skin layers is therefore lower at these PTs. The lower remaining dose of SLS also explains this distinction, especially for the VS. Additionally, there are presumed reactions in deeper layers of the epidermis and dermis at PT 3-4. CONCLUSIONS: In summary, all data suggest a different reaction pattern from the classical irritant response. Therefore, application without any PT seems to be best suited for irritancy skin testing, especially for visual assessment. PTs prior to irritant patch testing have been shown to be unjustifiable.

Adult↗

PubMed2001

Relationship between systemic corticosteroids and osteonecrosis.

Numerous reports describe osteonecrosis after oral corticosteroid therapy. It is still uncertain if corticosteroid treatment alone or in combination with other factors leads to the development of this condition. The literature presents controversial clinical and experimental data. The most affected site for osteonecrosis is the femoral head and therefore our considerations are concentrated at this site. Oral corticosteroids are commonly used in dermatology, especially in the treatment of connective tissue diseases and hypersensitive diseases. This clinical review evaluates the relationship between and the onset of femoral head necrosis. Although osteonecrosis of the femoral head can be caused by various conditions such as trauma, excess alcohol and hemoglobinopathies, studies indicate that treatment with corticosteroids is the most common cause of the condition. There is some controversy on the role of underlying disease and total corticosteroid dose administered, in the development of osteonecrosis of the femoral head. MRI scans are used to establish an early diagnosis. There are several surgical and nonsurgical options for disease management, dependent on the stage of disease, the age of the patient and other risk factors. In general, the risk for osteonecrosis is considered to be low under oral corticosteroid therapy. So far, no data can establish a direct relationship, but data still strongly suggest an existing cause and effect relationship. Further investigations are necessary for example, a large controlled prospective long-term study, to further refine an association between the corticosteroid dose, the duration of treatment and other risk factors. Dermatologists who prescribe oral corticosteroids, should always be aware of the potential risk of avascular femoral head necrosis and the patients should be informed about this severe complication of oral coricosteroid therapy.

Adrenal Cortex Hormones↗