Contact allergy to isothiazolinone derivatives: unusual clinical presentations.

Contact allergic reactions to the mixture of 5-chloro-2-methyl-4-isothiazoline-3-one and 2-methyl-4-isothiazoline-3-one are most frequently associated with intolerance to cosmetics. The present article points out that such reactions, particularly on the face, can have unusual clinical presentations that are very similar to seborrheic eczema, lupus erythematosus, lymphocytic infiltrate or photodermatitis. Atopic dermatitis is also often erroneously suspected.     

Lymphocyte transformation test in patients with nickel sensitivity: an aid to diagnosis

Peripheral blood lymphocytes from 16 patients with a positive patch test to 2.5% nickel sulphate (NiSO4) and 18 healthy controls were tested by the lymphocyte transformation technique where NiSO4 in six different concentrations was used and tested after various days of culture. Lymphocytes from all except one of the patients showed a significantly greater response than that of the controls. Lymphocyte transformation as measured by increased DNA synthesis seems to be a valuable tool for investigating the problems arising from false-positive or false-negative patch tests. With these data we have defined certain criteria for in vitro reactivity that should be fulfilled. Lymphocytes from controls responded non-specifically to high concentrations of NiSO4. Cord blood lymphocytes from 4 newborn infants could also be activated by NiSO4, thus confirming the assumption that NiSO4 is a weak mitogen.     

Lymphocyte transformation test in detection of drug hypersensitivity

Four thousand, three hundred and ninety-two lymphocyte transformation tests with seventy-nine different drugs were performed in 1723 patients because of the clinical suspicion of drug hypersensitivity. The optimal stimulating concentration and the lowest cytotoxic concentration were determined for every drug, and transformation tests were carried out only with those drugs whose optimal stimulating concentration was lower than its lowest cytotoxic concentration. The transformation tests gave positive results in 557 of the 1723 patients (32%); hypersensitivity to one drug could be confirmed in 410 cases (24%), and to two or more drugs in 147 cases (9%). It is considered that the test is a valuable in vitro method in the diagnosis of drug allergy, and that its application can lead to a substantial decrease in the number of patients who must be subjected to the possible risk of in vivo tests for the determination of the sensitizing drug.     

Lymphocyte transformation test in patients with American leishmaniasis

To determine the correlation between the lymphocyte transformation test (LTT) with phytohemagglutinin (PHA) and the clinical forms of American leishmaniasis (AL), duration of the disease and reaction to leishmanin, the authors studied 12 patients and compared them to 25 unaffected individuals. The ulcerated cutaneous form of the disease was observed in 4 patients, the ulcero-nodular lymphangitic form in 1, the mucous cutaneous form with destruction of the nose in 6, and the verrucous form in 1. General patient condition was satisfactory and the Montenegro reaction macroscopically positive with infiltrations of 5-15 mm in diameter. The results revealed no evidence of immunodeficiency among patients. No correlation was observed between clinical forms, duration of the disease and Montenegro reaction and LTT results. LTT with PHA does not appear to be an adequate indicator of the cell immune system in AL cases.     

Lymphocyte transformation test in allergic contact nickel dermatitis

Twenty-five patients with clinically proven, patch test positive nickel dermatitis were studied with the lymphocyte transformation test (LTT). Serial dilutions of NiSO4 were present in the lymphocyte culture. None of the controls showed lymphocyte blast transformation. In fourteen patients maximal incorporation of thymidine occurred at the highest dilutions (I:50,000-I:100,000). In eleven patients the highest incorporation occurred at the lower dilutions. The nature of the antigen responsible for the specific reaction remains unknown.     

Lymphocyte transformation test in Gell's and Coombs' drug reactions]

A method of interpretation of the lymphocyte transformation test is described which results on the basis of statistical evaluation. With this method good results were received in cases of drug induced side effects of type I according to Gell and Coombs. The investigations on 61 patients have shown that differneces between the clinical findings and lymphocyte transformation tests are rare. They are mainly in relation to false-positive reactions of the lymphocyte transformation test in Penicillin allergy.     

Lymphocyte transformation in mycosis fungoides

Summary Lymphocyte transformation tests with PHA were carried out in 26 patients with mycosis fungoides (MF) in different stages of the disease.In premycotic and infiltrative stages of MF there were no significant disturbances in the lymphocyte response to PHA.Inhibition of DNA synthesis and blastic transformation was observed only in the tumorous stage. The results are in favour of the nosological distinctiveness of mycosis fungoides within the lymphoma group.

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Zusammenfassung Bei 26 Mycosis fungoides-Kranken wurde in den verschiedenen Krankheitsstadien ein Lymphocyten-Transformationstest mit PHA durchgeführt.Im prämykotischen und infiltrativen Stadium der MF gab es keine bedeutenden Störungen in der Lymphocyten-Reaktion auf PHA.Eine Inhibition der DNS-Synthese und blastische Transformation war nur in der Tumorperiode zu beobachten. Die Resultate sprechen für die nosologische Verschiedenheit der Mycosis fungoides in der Lymphomgruppe.

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Herrn Prof. H. Götz zum 60. Geburtstag gewidmet.