Diagnostic significance of colloid body deposition in direct immunofluorescence.

Background: Colloid bodies (CB) in direct immunofluorescence (DIF) studies are usually found in interface dermatitis. Furthermore, CB can be found in various skin diseases and even in normal skin. Aim: To evaluate the diagnostic value of CB deposits in DIF studies. Methods: From 1996-2007, data from 502 patients where DIF studies showed immunoreactants at CB were enrolled. The definite diagnoses of these patients were based on clinical, histopathological and immunofluorescent findings. The results of DIF studies were analyzed. Results: Immunoreactants at CB were detected in 44.4%, 43.8%, 4.2%, 3.8%, and 2.2% of interface dermatitis, vasculitis, autoimmune vesiculobullous disease, panniculitis, and scleroderma/morphea, respectively. The most common immunoreactant deposit of all diseases was Immunoglobulin M (IgM). Brighter intensity and higher quantity of CB was detected frequently in the group with interface dermatitis. Conclusions: Immunoreactant deposits at CB alone can be found in various diseases but a strong intensity and high quantity favor the diagnosis of interface dermatitis. CB plus dermoepidermal junction (DEJ) deposits are more common in interface dermatitis than any other disease. Between lichen planus (LP) and discoid lupus erythematosus (DLE), CB alone is more common in LP; whereas, CB plus DEJ and superficial blood vessel (SBV) is more common in DLE. The most common pattern in both diseases is CB plus DEJ. The quantity and intensity of CB in LP is higher than in DLE.

Autologous serum skin test in chronic idiopathic urticaria: prevalence, correlation and clinical implications.

Some cases of chronic idiopathic urticaria (CIU) have histamine-releasing IgG autoantibodies in their blood. This disease subgroup is called "autoimmune urticaria". To date, the autologous serum skin test (ASST) is the best in vivo clinical test for the detection of basophil histamine-releasing activity in vitro. This study aimed to find the prevalence of ASST positive cases in Thai patients with CIU, to identify factors related to the positivity of ASST and to find the clinical implications of ASST in CIU. A retrospective study was performed among 85 CIU patients who attended the Urticaria Clinic at the Department of Dermatology, Siriraj Hospital and were willing to perform ASST, from January 2002 to December 2003. Twenty-one (24.7%) patients had a positive ASST. There was no significant difference between patients with positive ASST and negative ASST as to the severity of the disease (wheal numbers, wheal size, itching scores and the extent of body involvement) as well as the duration of the disease.

Direct immunofluorescence study in Thai patients with scleroderma.

OBJECTIVE: Previous reports of direct immunofluorescence (DIF) studies of the skin biopsies in scleroderma were either negative or positive at various percentages and patterns. The present study was designed to evaluate the positive yield and pattern of DIF in Thai patients with scleroderma and its possible clinical correlation. MATERIAL AND METHOD: Twenty-two patients with localized or systemic sclerosis, who attended the Department of Dermatology, Siriraj Hospital, from 1996 to 2002, were enrolled in the present study. Skin biopsy was performed for DIF studies. RESULTS: Nine out of 22 patients were diagnosed with systemic sclerosis (SS), eleven with morphea, and two with overlapping syndrome. Fifteen of 22 patients (68%) had positive DIF findings; seven of nine (78%) patients with SS, six of eleven (55%) patients with morphea and two of two (100%) with overlapping syndrome. The common sites of deposit in SS, morphea and overlapping syndrome were dermo-epidermal junction and epidermal nuclei. The common immunoreactant deposit in all groups was IgM. There was no significant difference in the comparison of DIF findings with duration of biopsy lesion, clinical correlation, and the positive result of serum antinuclear antibody (ANA) in the three groups of patients. CONCLUSION: Positive DIF yield in the present study was higher than previous reports from Western countries. Similar to the study reported from Western country, there was no statistical significant difference in comparison of DIF findings with the duration of lesion, clinical correlation, and the positive result ofserum ANA in our three groups of patients. However; patients with SS had a tendency to give more frequently positive ENS and DEJ deposits than those with morphea.

Cutaneous leukocytoclastic vasculitis: the yield of direct immunofluorescence study.

BACKGROUND: Leukocytoclastic vasculitis (LCV) is a clinico-pathological entity. Previous direct immunofluorescence study (DIF) studies of vasculitis showed positive findings mainly in the early stage of the disease. OBJECTIVE: To study the positive yield and patterns of DIF in patients with various stages of LCV. DESIGN: One hundred patients with LCV who attended the Department of Dermatology, Siriraj Hospital from 1997 to 2000 were enrolled in the study. RESULTS: The study showed immunoreactive deposits in blood vessel walls in 76 cases (76%). Forty seven per cent of patients showed immunoreactant deposit only in superficial blood vessel walls, 3% had deposits only in deep blood vessel walls. Superficial and deep blood vessel wall deposits were seen in 26%. Dermo-epidermal deposit in addition to blood vessel wall deposit was found in 39%. The most common immunoreactive deposit was C3 (71%), followed by IgM (35%), IgA (12%) and IgG (8%) respectively. The age of the skin lesions at the time of biopsy ranged from 1 to 7 days. 82% of patients with one day old lesions showed immunoreactive deposits in the blood vessel walls and 74% of the group with lesions aged 2-7 days at the time of biopsy showed immunoreactive deposits in the blood vessel walls. CONCLUSION: The present study showed a 76% positive yield for DIF study in patients with LCV when biopsies were performed within one week of onset. There was a tendency for the percentage of positive DIF results to decline when the biopsy was performed on lesions that were more than 1 day old.