Bullous lesions following phototherapy in a newborn

ABSTRACT A male infant presented with progressive jaundice immediately after birth. Fecal acholia and choluria associated with extensive bullous skin lesions in his trunk, abdomen, and upper and lower limbs developed during phototherapy. Several diagnostic hypotheses were presented, including neonatal porphyria, hemochromatosis, Alagille syndrome, and neonatal lupus. A 24-hour urine sample for the dosage of urinary porphyrins was collected, showing high results (1823.6µg in 100mL). At 50 days of life, fluorescence spectroscopy using a Wood’s lamp revealed simultaneous bright red fluorescence of urine-stained diapers and sample blood. A definitive diagnosis of congenital erythropoietic porphyria was made following identification of a mutation of the uroporphyrinogen synthetases III gene on genetic testing. The patient was subsequently maintained in a low light environment since then, resulting in improvement of the lesions. Congenital erythropoietic porphyria is a disease of the group of porphyrias that presents shortly after birth with blistering occurring in regions exposed to the sun or other ultraviolet light. Atrophic scars, mutilated fingers, and bright red fluorescence of the urine and teeth may also be observed. There is no specific treatment, and prophylaxis comprising a total avoidance of sunlight is generally recommended. A high degree of suspicion is required for diagnosis. An early diagnosis can lead to less damage. Here, we present the case of a newborn with congenital erythropoietic porphyria diagnosed after presenting with bullous lesions secondary to phototherapy.摘要 1例男婴出生后即刻出现进行性黄疸。光疗期间，患儿出现白陶土样粪便及胆红素尿，伴躯干、腹部及上下肢广泛大疱性皮肤损害。当时提出了多项鉴别诊断假设，包括新生儿卟啉病、血色病、阿拉基尔综合征（Alagille syndrome）及新生儿红斑狼疮。采集24小时尿标本检测尿卟啉含量，结果显著升高（100mL尿液中含1823.6μg）。出生后第50天，采用伍德灯（Wood’s lamp）行荧光光谱检测，可见尿渍尿布及血液标本均呈现亮红色荧光。经基因检测发现尿卟啉原Ⅲ合成酶（uroporphyrinogen III synthase）基因存在突变后，最终确诊为先天性红细胞生成性卟啉病（congenital erythropoietic porphyria）。此后将患儿安置于低光照环境中，皮损得到改善。 先天性红细胞生成性卟啉病属于卟啉病谱系疾病，多于出生后不久发病，暴露于日光或其他紫外线的部位可出现水疱。患者还可出现萎缩性瘢痕、手指残毁，以及尿液与牙齿的亮红色荧光。该病暂无特效治疗方案，临床通常建议采取完全避光的预防措施。诊断该病需保持高度警惕，早期诊断可减轻机体损伤程度。本文报告1例因光疗后继发大疱性皮损而确诊的先天性红细胞生成性卟啉病新生儿病例。