Abstract:

Background information: The diagnosis making in patient’s acute appendicitis poses a diagnostic challenge worldwide, despite much advancement in abdominal surgery. The Modified Alvarado Score has been reported to be a cheap and quick diagnostic tool in patients with acute appendicitis. However a difference in sensitivities and specificities has been observed when the scores were applied to various populations and clinical settings. This study analyses its diagnostic utility in patients with acute appendicitis in our local setting.

Methods: A Descriptive cross-sectional study involving all patients with a clinical diagnosis of acute appendicitis at Bugando Medical Centre over a six-month period between November 2008 and April 2009 was conducted. All patients who met the inclusion criteria were consecutively enrolled in the study. They were evaluated on admission using the MASS to determine whether they had acute appendicitis or not. All patients underwent appendicectomy. The decision to operate was the prerogative of the surgeon or surgical resident based on overall clinical judgment and not the MASS. The diagnosis was confirmed by histopathological examination. Data was collected using a pre-tested coded questionnaire and analyzed using SPSS statistical computer software.

Results: A total number of 127 patients were studied. Their age ranged from eight to 76 years (mean 29.64 ± 12.97). There were 37 (29.1%) males and 90 (70.9%) female (M: F=1:2.4). All patients in this study underwent appendicectomy. The perforation rate was 9.4%. Histopathological examination confirmed appendicitis in 85 patients (66.9%) and the remaining 42 patients had normal appendix giving a negative appendicectomy rate of 33.1% (26.8%) for males and 38.3% for females). The sensitivity and specificity of MASS in this study were 94.1% (males 95.8% and females 88.3%) and 90.4% (males 92.9% and female 89.7%) respectively. The PPV and NPV were 95.2% (males 95.5% and female 90.6%) and 88.4% (males 89.3% and females 80.1%) respectively. The accuracy of Mass was 92.9% (males 91.5% and females 87.6%).

Conclusion and Recommendations: The study shows that use of MASS in patients suspected to have acute appendicitis provides a high degree of diagnostic accuracy and can be employed at Bugando Medical Centre to improve the diagnostic accuracy of acute appendicitis and subsequently reduces negative appendicectomy and complication rates. However, additional investigations may be required to confirm the diagnosis in case of females and atypical presentation.