Gene rearrangement in positive patch tests.

Lymphoproliferative disorders are usually characterized by lymphoid infiltrates that demonstrate clonality in contrast to inflammatory or reactive infiltrates of the skin that are polyclonal without detectable monoclonal populations of T-cells. Probably the southern blot analysis of TCR gene rearrangement can help to delineate the reactive from the malignant processes. In this study, we applied the technique on benign reactive processes in the skin. We examined biopsies from positive patch tests from patients with a delayed hypersensitivity reaction. We found the same gene rearrangement configuration in 11 of 17 patients with positive patch tests. The extra band revealed in these cases was situated in the EcoR1 digested DNA lane at the 8.0 Kb, between the 2 germline bands at the 11 Kb and the 4 Kb respectively. This observation was not correlated to the degree of the inflammatory response or to the specific hapten induced reaction. This pattern was not found in any of 107 patients with malignant diagnoses, but also in six of 43 patients with benign diseases. The clinical implication may suggest the presence or development of clonality in benign inflammatory disorders.

Analyses of T-cell receptor beta-chain genes by Southern blotting in known and suspected cutaneous T-cell lymphoma. A study of 67 samples from 32 patients.

In this study we have investigated the configuration of the T-cell receptor (TCR) beta-chain genes in benign cutaneous conditions (n = 5) and known (n = 22) or suspected (n = 5) cutaneous T-cell lymphoma (CTCL). Sequential biopsies from skin, lymph node, blood and/or bone marrow were available in 12 cases of the 22 confirmed CTCL, and a total of 67 samples were analysed. In the benign conditions, clonal rearrangements of the TCR beta-chain genes were seen in neither skin nor blood samples. In contrast, in CTCL clonal rearrangements were detected in all skin samples from plaque or tumour lesions of mycosis fungoides. Clonal TCR rearrangements were also present in skin and blood samples from two patients with Sèzary's syndrome, and in skin and blood samples from three of five patients with clinically suspected CTCL. In 10 patients with large cell lymphomas, clonal rearrangements were detected in skin samples in half of the cases. In the remaining patients, clonal TCR rearrangements could not be detected in the skin, but only in the blood and/or bone marrow specimens. Results from the analyses of sequential biopsies showed identical patterns of rearrangement in 11 patients. In the remaining patient, the pattern of rearrangement differed between skin and lymph node. These data confirm and extend previous reports and indicate that analysis of TCR beta-chain genes by Southern blotting forms a useful supplement to other methods for the diagnosis of known and suspected CTCL. They also emphasize the importance of studying not only skin, but also extracutaneous sites.

Subclinical human papilloma virus infection in condylomata acuminata patients attending a VD clinic.

In 37 (77%) of 48 patients with external genital warts, application of 5% acetic acid revealed areas of acetowhite epithelium. The lesions were not clinically apparent before acetic acid was applied but were easily detected without the use of a colposcope. In a control group of 20 patients with chlamydial urethritis and no history of genital warts, none had acetowhite genital lesions. Histological examination of biopsy specimens from the flat acetowhite lesions showed HPV infection with koilocytosis in 29 (78%) and in 3 (8%) intra-epithelial neoplasia grade II-III. Using in situ hybridization with commercially available biotinylated DNA probes, HPV types 16/18 could be detected in 7 (24%) patients with koilocytosis and in 3 (100%) patients with dysplasia. Simultaneous infection with HPV types 6/11, 16/18, and 31/33/35 was found in 8 of the 13 HPV DNA-positive patients. It is concluded that subclinical HPV-induced acetowhite lesions are common among patients with genital warts and that these flat lesions may be associated with a high grade of dysplasia. Consequently, routine use of the acetic acid test on the genital epithelium is recommended in patients with condylomata acuminata in order to diagnose and treat all HPV-infected areas.