Khandpur Sujay, Ahuja Rhea
Department of Dermatology and Venereology, All India Institute of Medical Sciences, New Delhi 110029, India.
Dermatopathology (Basel). 2022 May 7;9(2):164-171. doi: 10.3390/dermatopathology9020021.
Maculopapular exanthem is a commonly encountered presentation in routine clinical practice, and differentiation between its two most common etiologies, i.e., viral- and drug-induced, often poses a diagnostic dilemma. Clinical, hematological and biochemical investigations are seldom reliable in distinguishing between a drug reaction and a viral exanthem. Certain key histopathological features such as the presence of a moderate degree of spongiosis, extensive basal cell damage with multiple necrotic keratinocytes and dermal infiltrate rich in eosinophils or lymphocytes and histiocytes may favor a drug exanthem, while distinctive epidermal cytopathic changes and lymphocytic vasculitis point towards a viral etiology. Similarly, notable immunohistochemical markers such as IL-5, eotaxin and FAS ligand may support a diagnosis of a drug-induced maculopapular eruption. Histopathological and immunohistochemical evaluations may help in distinguishing between the two etiologies when faced with a clinical overlap, especially in patients on multiple essential drugs when drug withdrawal and rechallenge is not feasible.
斑丘疹性皮疹是日常临床实践中常见的表现，区分其两种最常见的病因，即病毒感染和药物引起的，常常会造成诊断难题。临床、血液学和生化检查在区分药物反应和病毒疹方面很少可靠。某些关键的组织病理学特征，如存在中度海绵形成、广泛的基底细胞损伤伴多个坏死角质形成细胞以及富含嗜酸性粒细胞或淋巴细胞和组织细胞的真皮浸润，可能提示药物疹，而独特的表皮细胞病变变化和淋巴细胞性血管炎则指向病毒病因。同样，显著的免疫组化标志物如白细胞介素-5、嗜酸性粒细胞趋化因子和FAS配体可能支持药物性斑丘疹性皮疹的诊断。当面临临床重叠情况时，尤其是在服用多种必需药物且停药和再激发不可行的患者中，组织病理学和免疫组化评估可能有助于区分这两种病因。
