Kundiona I, Chihaka O B, Muguti G I
Cent Afr J Med. 2015 Sep-Dec;61(9-12):66-73.
High negative appendicectomy rates are no longer acceptable with improvements in imaging techniques and clinical prediction rules. The use of ultrasound and CT scan in addition to clinical assessment and blood investigations has greatly reduced the negative appendicectomy rate to less than 10%.
The aim of the study was to determine the negative appendicectomy rate at the two major teaching hospitals in Harare and to evaluate the accuracy of the Alvarado score and ultrasound scan in diagnosing acute appendicitis.
Prospective observational, cross sectional study.
Parirenyatwa Group of Hospitals and Harare Central Hospital, in Zimbabwe.
A total of 206 patients undergoing appendicectomy at the two major teaching hospitals in Harare were included in this study between June 2012 and May 2013. Information recorded included: age, sex, clinical features, investigations and treatment. Alvarado score was calculated from the data in the case notes and ultrasound scan results were also captured. All appendices removed at operation were sent for histopathological examination. Appendicitis was confirmed at histology. The positive predictive value of Alvarado score and sensitivity and specificity of ultrasound scan were calculated.
The overall negative appendicectomy rate was 16.5%. The negative appendicectomy rate for men was 13.3% and that for females was 24.4%. The negative appendicectomy rate for Parirenyatwa Group of Hospitals was 19.0% and that for Harare Central Hospital was 12.1%. The mean age was 28 years (SD 12.8). Appendicitis was diagnosed commonly in the second and third decades of life. Sensitivity of ultrasound scan in diagnosing acute appendicitis was 89.5% with a positive predictive value of 77.2%. Females were 2.6 times more likely to have an ultrasound scan done to diagnose appendicitis than males. Alvarado score had a sensitivity of 95.3% with a positive predictive value of 90.3%.
The negative appendicectomy rate (16.5%) at the two University Teaching Hospitals in Harare is relatively high when compared with modern trends. Alvarado score had a high sensitivity (95.3%) and predictive value (90.3%). Ultrasound scan had a high sensitivity (89.5%) and a relatively low predictive value (77.2%) in diagnosing acute appendicitis. Regular use of these assessment modalities should contribute substantially to reduction in the negative appendicectomy rate in our practice.
随着影像技术和临床预测规则的改进，高阴性阑尾切除率已不再能被接受。除临床评估和血液检查外，超声和CT扫描的应用已大幅降低阴性阑尾切除率至10%以下。
本研究旨在确定哈拉雷两家主要教学医院的阴性阑尾切除率，并评估阿尔瓦拉多评分及超声扫描在诊断急性阑尾炎中的准确性。
前瞻性观察性横断面研究。
津巴布韦的帕里伦亚瓦医院集团和哈拉雷中心医院。
2012年6月至2013年5月期间，哈拉雷两家主要教学医院共206例行阑尾切除术的患者纳入本研究。记录的信息包括：年龄、性别、临床特征、检查及治疗情况。根据病历数据计算阿尔瓦拉多评分，并记录超声扫描结果。所有术中切除的阑尾均送病理组织学检查，以组织学确诊阑尾炎。计算阿尔瓦拉多评分的阳性预测值及超声扫描的敏感性和特异性。
总体阴性阑尾切除率为16.5%。男性阴性阑尾切除率为13.3%，女性为24.4%。帕里伦亚瓦医院集团的阴性阑尾切除率为19.0%，哈拉雷中心医院为12.1%。平均年龄为28岁（标准差12.8）。阑尾炎常见于20至30岁年龄段。超声扫描诊断急性阑尾炎的敏感性为89.5%，阳性预测值为77.2%。女性因诊断阑尾炎而行超声扫描的可能性是男性的2.6倍。阿尔瓦拉多评分的敏感性为95.3%，阳性预测值为90.3%。
与现代趋势相比，哈拉雷两家大学教学医院的阴性阑尾切除率（16.5%）相对较高。阿尔瓦拉多评分具有较高的敏感性（95.3%）和预测值（90.3%）。超声扫描在诊断急性阑尾炎方面具有较高的敏感性（89.5%）和相对较低的预测值（77.2%）。在我们的实践中，定期使用这些评估方法应能大幅降低阴性阑尾切除率。
