GASTROINTEST ENDOSC：缺铁性贫血病人的微型肠道胶囊内镜检查

　　最近在《消化内镜》上发表的一篇文章评估了缺铁性贫血病人的微型肠道胶囊内镜检查的诊断价值。[Gastrointest Endoscopy 2012: 76(5): 983-992]

　　在全球范围，缺铁性贫血是贫血的最常见原因。最近的指南推荐在缺铁性贫血病人中进行微型肠道胶囊内镜检查，但缺铁性贫血病人微型肠道胶囊内镜检查有效性的证据还比较有限。

　　英国的Anastasios Koulaouzidis医生的研究小组评估了缺铁性贫血病人微型肠道胶囊内镜检查的诊断能力。他们的研究基于相关研究的数据库。

　　研究小组检索了相关文章，其中两名研究者独立进行了数据搜集和提取。在24项研究中共有1960名行微型肠道胶囊内镜检查的缺铁性贫血病人入选。研究小组的首要评估指标包括对每个病人的诊断能力（95%置信区间），同时还进行了亚组分析。经随即效应模型评估，研究者收集的数据显示缺铁性贫血微型肠道胶囊内镜的诊断效能为47%，但各个研究之间存在很大的异质性。

　　研究小组指出，仅针对缺铁性贫血进行的微型肠道胶囊内镜研究显示其诊断效力为67%，而并非仅针对缺铁性贫血的研究显示诊断效力为44%。特别地，在亚组1中，微型肠道胶囊内镜可以更好地发现血管性、炎症性和肿块或肿瘤。

　　Anastasios医生总结道：“尽管一些因素（如研究的异质性和入选研究的质量）需要考虑，这项分析仍证明了微型肠道胶囊内镜在缺铁性贫血病人中的有效性。”

Diagnostic yield of small-bowel capsule endoscopy in patients with iron-deficiency anemia: a systematic review

Background

Iron-deficiency anemia (IDA) is the most common cause of anemia worldwide. Current guidelines recommend the use of small-bowel capsule endoscopy (SBCE) in IDA. Evidence of the validity of SBCE in patients with IDA alone is still limited.

Objective

To assess the diagnostic yield (DY) of SBCE in IDA by pooling data from relevant studies.

Design

Systematic review and meta-analysis. Fixed-effects or random-effects models were used as appropriate.

Setting

Studies that estimated the DY of SCBE in IDA were identified. Two investigators independently conducted the search and data extraction.

Patients

A total of 24 studies enrolling 1960 patients with IDA who underwent SBCE were included.

Main Outcome Measurements

Per-patient DY, with 95% confidence intervals. Subgroup analysis was also performed.

Results

The pooled DY of SBCE in IDA, evaluated by a random-effects model, was 47% (95% CI, 42%-52%), but there was statistically significant heterogeneity among the included studies (inconsistency index [I2] = 78.8%, P < .0001). The pooled DY of SBCE in studies focused solely on patients with IDA (subset 1, 4 studies) was 66.6% (95% CI, 61.0%-72.3%; I2 = 44.3%); conversely, that of studies not focusing only on IDA patients (subset 2, 20 studies) was 44% (95% CI, 39%-48%; I2 = 64.9%). In particular, more vascular (31% vs 22.6%, P = .007), inflammatory (17.8% vs 11.3%, P = .009), and mass/tumor (7.95% vs 2.25%, P < .0001) lesions were detected with SBCE in patients participating in the studies in subset 1.

Limitations

Heterogeneity of studies, retrospective design, and selection bias.

Conclusions

This analysis demonstrates the validity of SBCE in the investigation of patients with IDA and negative findings on a previous diagnostic workup, although certain factors such as heterogeneity and quality of the included studies should be taken into account.