Trautmann A, Seitz C S, Stoevesandt J, Kerstan A
Department of Dermatology and Allergy, University Hospital Würzburg, Würzburg, Germany.
Clin Exp Allergy. 2014 Dec;44(12):1531-8. doi: 10.1111/cea.12437.
The lymphocyte transformation test (LTT) has been promoted as in-vitro test for diagnosis of drug hypersensitivity. For determination of statistical LTT sensitivity, series of patients with clinically uniform reactions followed by complete drug hypersensitivity work-up are mandatory. Assessment of LTT specificity requires control patients who tolerated exposure to the drug studied.
To prospectively determine the diagnostic value of the LTT in a clinically and diagnostically well-defined series of patients.
Patients with exanthematous skin eruptions after ampicillin (AMP) intake were included in this study. After exclusion or confirmation of delayed-onset allergic AMP hypersensitivity by skin and provocation testing, two independent LTTs were performed: one standard LTT and a modified LTT with additional anti-CD3/anti-CD28 monoclonal antibody stimulation.
By testing, delayed-onset allergic AMP hypersensitivity was diagnosed in 11 patients and definitely ruled out in 26. The standard LTT reached a diagnostic sensitivity of 54.5% while the modified LTT yielded 72.7%. However, the methodical test modification resulted in a decline of specificity from 92.3% (standard LTT) to 76.9%.
In cases of AMP-associated exanthems, the diagnostic value of the LTT compared with routine allergy testing is limited. When evaluating such exanthems, provocation testing remains the gold standard. Delayed reading of intradermal skin tests remains most useful to avoid positive provocation reactions.
淋巴细胞转化试验（LTT）已被推广作为药物超敏反应诊断的体外试验。为了确定LTT的统计学敏感性，必须对一系列临床反应一致且随后进行完整药物超敏反应检查的患者进行研究。评估LTT的特异性需要有耐受所研究药物暴露的对照患者。
前瞻性地确定LTT在一系列临床和诊断明确的患者中的诊断价值。
本研究纳入了服用氨苄西林（AMP）后出现皮疹的患者。通过皮肤和激发试验排除或确认迟发性过敏性AMP超敏反应后，进行两项独立的LTT：一项标准LTT和一项采用额外抗CD3/抗CD28单克隆抗体刺激的改良LTT。
通过检测，11例患者被诊断为迟发性过敏性AMP超敏反应，26例被明确排除。标准LTT的诊断敏感性为54.5%，而改良LTT为72.7%。然而，方法学上的试验改良导致特异性从92.3%（标准LTT）降至76.9%。
在AMP相关皮疹病例中，与常规过敏试验相比，LTT的诊断价值有限。在评估此类皮疹时，激发试验仍是金标准。皮内皮肤试验延迟读数对于避免激发试验阳性反应最为有用。
