Laboratorio de Errores Innatos del Metabolismo y Tamiz, Instituto Nacional de Pediatria, Secretaria de Salud, Mexico.
J Med Screen. 2011;18(3):115-20. doi: 10.1258/jms.2011.011028.
To expose causes leading to the delayed arrival of phenylketonuria (PKU) patients at a governmental reference centre (RC), and to describe their clinical characteristics. Material and methods PKU files registered during the past 18 years at the National Institute of Pediatrics in Mexico City were evaluated. Patients were classified into two groups according to their age at arrival: Group I (early reference), patients arriving during the first month of life; and Group II (late reference), those who arrived after thirty days of age. Time and causes of delay were documented.
Of 57 recorded files, 10 were classified in Group I and 47 in Group II. Causes leading to the late arrival of Group II patients were absence of routine newborn screening (NBS), PKU not included in the routine NBS, sampling after the recommended age, false negative result, results without interpretation and/or instructions to follow, delayed notification of results, poor medical criteria of attending physician, difficulties in obtaining confirmatory tests, and administrative failures.
The main cause of late referral of PKU patients was the absence of PKU testing. As a developing country, Mexico still faces challenges in the proper functioning and expansion of the NBS programme. Most PKU patients arrived at the RC late, presenting with varying degrees of the clinical spectrum. Incorporating PKU testing into the already established Mexican NBS system and adding quality indicators to guarantee proper operation in all NBS phases is necessary to achieve the goal of identifying, referring, diagnosing, and treating patients promptly.
揭示导致苯丙酮尿症（PKU）患者延迟到政府参考中心（RC）就诊的原因，并描述其临床特征。
评估了过去 18 年在墨西哥城国家儿科研究所登记的 PKU 档案。根据患者就诊时的年龄将其分为两组：第 I 组（早期就诊），即出生后第一个月内就诊的患者；第 II 组（晚期就诊），即 30 天后就诊的患者。记录就诊时间延迟的原因。
在记录的 57 份档案中，10 份被归类为第 I 组，47 份被归类为第 II 组。导致第 II 组患者就诊延迟的原因包括新生儿常规筛查（NBS）未进行、PKU 未纳入常规 NBS、采样时间晚于推荐年龄、假阴性结果、结果无解释和/或随访指导、结果通知延迟、主治医生的医疗标准较差、确认性检测困难以及行政失误。
PKU 患者就诊延迟的主要原因是未进行 PKU 检测。作为一个发展中国家，墨西哥在适当运作和扩大 NBS 计划方面仍面临挑战。大多数 PKU 患者就诊较晚，表现出不同程度的临床症状。将 PKU 检测纳入现有的墨西哥 NBS 系统，并添加质量指标以保证所有 NBS 阶段的正常运行，对于及时识别、转诊、诊断和治疗患者以实现目标是必要的。
