Hypersensitivities skin testing

The most common in vivo assay of lymphocyte function is the delayed hypersensitivity skin test. This test specifically evaluates the presence... 

The accepted indications for delayed hypersensitivity skin testing include evaluation of immune disorders or chronic diseases that cause cellular immune dysfunction (e.g., uremia, cancer, AIDS, etc), exposure to infectious pathogens (e.g., Mycobacterium tuberculosis), evaluation of nutritional status (because malnutrition can result in cell-mediated immune deficiency), and in some cases, assessment of immune senescence. 

The first patient treated with a thymic factor was a 4-year-old girl with thymic hypoplasia and abnormal immunoglobulin synthesis (Wara et al, 1975 Wara, 1983). She was treated with TF5 at a dose of 20 mg/kg/week for a total of 33 months. After 1 month of thymosin therapy, she had conversion of delayed hypersensitivity skin tests as well as an increase in absolute lymphocyte count. In addition, T cell percentages increased from 10 to 60% and serum immunoglobulin levels increased from 220 to 1220 mg/dl. However, no effects were seen on T cell functions in lymphoproliferative responses to T cell mitogens or in MLR. The patient s clinical condition improved with a decrease in the number and severity of infections and diarrhea. She has continued off therapy and appears healthy at age 13. This initial success prompted the many subsequent therapeutic attempts with a variety of thymic preparations. 

As in other types of drug hypersensitivity, skin testing often yields variable results. Farah and Shbaklu (1971) reported positive skin tests on intradermal injections of progesterone and confirmed the sensitivity of both their patients by passive cutaneous transfer tests. Falliers (1974) noted that 10 out of 11 women with either allergic rhinitis/asthma or urticaria had strong positive wheal and erythema reactions. In contrast, the patients treated by Pelikan (1978) did not show a good correlation between the results of nasal provocation and either scratch or patch tests. 

Brockow K, Romano A, Aberer W et al Skin testing in patients with hypersensitivity reactions to iodinated contrast media - a European multicenter study. Allergy 2009 64 234-241. 

For penicillin-allergic (nonanaphylactoid type) patients cefazolin 6 g/24 hours IV in 3 equally divided doses 6 IB Consider skin testing for oxacillin-susceptible staphylococci and questionable history of immediate-type hypersensitivity to penicillin cephalosporins should be avoided in patients with anaphylactoid-type hypersensitivity to P-lactams vancomycin should be used in these cases ... 

In a patient with a positive penicillin skin test or a history of immediate hypersensitivity to penicillin, vancomycin is the agent of choice. Vancomycin, however, kills S. aureus slowly and is generally regarded as inferior to penicillinase-resistant penicillins for MSSA. Penicillin-allergic patients who fail on vancomycin therapy should be considered for penicillin desensitization. 

Tuberculin skin testing is an important part of the care of all HIV-1-infected patients or persons at risk for HIV-1 infection. Tuberculin skin testing should be done using the Mantoux method. A tuberculin reaction of >5 mm of induration is classified as positive in persons known to have or suspected of having HIV-1 infection. Unfortunately, as the CD4 lymphocyte count declines with progression of HIV-1 disease, many patients no longer react to delayed-type hypersensitivity testing. More than 60% of persons with CD4 lymphocyte counts of <200 cells/pl may have skin test reactions of <5 mm. Thus, it is impossible to detect the presence of tuberculous infection in many HIV-l-infected individuals. 

Observations regarding the cellular immune response in PTSD are also consistent with enhanced GR responsiveness in the periphery. In one study, beclomethasone-induced vasoconstriction was increased in women PTSD subjects compared to healthy, non-trauma-exposed comparison subjects (Coupland et al. 2003). Similarly, an enhanced delayed-type hypersensitivity of skin test responses was observed in women who survived childhood sexual abuse vs those who did not (Altemus et al. 2003). Because immune responses, like endocrine ones, can be multiply regulated, these studies provide only indirect evidence of GR responsiveness. However, when considered in the context of the observation that PTSD patients showed increased expression of the re-... 

The incidence of nonallergic ampicillin eruptions is 40 to 100% in patients with concomitant Epstein-Barr virus (mononucleosis), cytomegalovirus, acute lymphocytic leukemia, lymphoma, or reticulosarcoma. Nonallergic penicillin-associated rashes are characteristically morbilliform (symmetrical, erythematous, confluent, maculopapular) eruptions on the extremities. The onset of typical nonallergic eruptions is more than 72 hours after (3-lactam exposure. The mechanism for the nonurticarial ampicillin rash is not known and is not related to IgE or type I hypersensitivity. Penicillin skin tests are not useful in the evaluation of nonurticarial ampicillin rashes. Patients with a history of nonurticarial ampicillin rashes may receive other (3-lactam antibiotics without greater risk of subsequent serious allergic reactions. 

A 75-year-old man developed triamcinolone-induced anaphylaxis and dose-related positive prick skin tests to triamcinolone, suggesting that an IgE-mediated hypersensitivity mechanism may have played a part... 

The authors of the last report commented that generalized delayed type hypersensitivity to systemic administration of a glucocorticoid is rare. Despite the potent immunosuppressive effect of glucocorticoids on immunocompetent cells, the clinical features, the skin biopsy specimen, and the positive delayed skin test reactions strongly suggested an immunological mechanism T cells were clearly involved and the high concentrations of interleukins 5, 6, and 10 were consistent with a T helper type 2 reaction. The raised concentrations of interleukin-5 were probably responsible for the blood and tissue eosinophilia. 

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