Kawakami Elisabete, Machado Rodrigo Strehl, Reber Marialice, Patrício Francy Reis S
Universidade Federal de São Paulo, Escola Paulista de Medicina, São Paulo, Brazil.
J Pediatr Gastroenterol Nutr. 2002 Jul;35(1):39-43. doi: 10.1097/00005176-200207000-00010.
Studies support the accuracy of 13C-urea breath test for diagnosing and confirming cure of Helicobacter pylori infection in children. Three methods are used to assess 13CO2 increment in expired air: mass spectrometry, infrared spectroscopy, and laser-assisted ratio analysis. In this study, the 13C-urea breath test performed with infrared spectroscopy in children and adolescents was evaluated.
Seventy-five patients (6 months to 18 years old) were included. The gold standard for diagnosis was a positive culture or positive histology and a positive rapid urease test. Tests were performed with 50 mg of 13C-urea diluted in 100 mL orange juice in subjects weighing up to 30 kg, or with 75 mg of 13C-urea diluted in 200 mL commercial orange juice for subjects weighing more than 30 kg. Breath samples were collected just before and at 30 minutes after tracer ingestion. The 13C-urea breath test was considered positive when delta over baseline (DOB) was greater than 4.0%.
Tests were positive for H. pylori in 31 of 75 patients. Sensitivity was 96.8%, specificity was 93.2%, positive predictive value was 90.9%, negative predictive value was 97.6%, and accuracy was 94.7%.
13C-urea breath test performed with infrared spectroscopy is a reliable, accurate, and noninvasive diagnostic tool for detecting H. pylori infection.
多项研究证实，¹³C尿素呼气试验在诊断和确认儿童幽门螺杆菌感染治愈方面具有准确性。有三种方法可用于评估呼出气体中¹³CO₂的增加量：质谱分析法、红外光谱法和激光辅助比率分析法。本研究对采用红外光谱法在儿童和青少年中进行的¹³C尿素呼气试验进行了评估。
纳入75例患者（年龄6个月至18岁）。诊断的金标准是培养阳性或组织学阳性以及快速尿素酶试验阳性。体重达30 kg的受试者，试验时服用50 mg¹³C尿素稀释于100 mL橙汁中；体重超过30 kg的受试者，服用75 mg¹³C尿素稀释于200 mL市售橙汁中。在摄入示踪剂前及摄入后30分钟采集呼气样本。当基线以上差值（DOB）大于4.0%时，¹³C尿素呼气试验被视为阳性。
75例患者中有31例幽门螺杆菌检测呈阳性。敏感性为96.8%，特异性为93.2%，阳性预测值为90.9%，阴性预测值为97.6%，准确性为94.7%。
采用红外光谱法进行的¹³C尿素呼气试验是检测幽门螺杆菌感染的一种可靠、准确且无创的诊断工具。
