Abstract:
Background: Acute appendicitis is a common surgical emergency. Its diagnosis can
be challenging. Scoring systems that make use of clinical and laboratory findings, like
the Alvarado score, have been developed to improve on the diagnosis of acute
appendicitis. Ultrasonography is used as an adjunct in the diagnosis. Correlation
between the clinical and ultrasound diagnosis with histopathology has been done in
various places globally, however, there is no data in our locality.
Objective: To assess accuracy of Alvarado score and Ultrasonography in comparison
to histopathology in the diagnosis of acute appendicitis at Moi Teaching and Referral
Hospital (MTRH).
Method: Hospital-based descriptive cross-sectional study at MTRH. Consecutive
sampling was done between January 2015 and June 2016. Patients who were
clinically diagnosed to have acute appendicitis and subsequently underwent
appendectomy were included. Questionnaires were used to collect data, which
included symptoms and signs at presentation and the ultrasound findings, obtained
from the case notes. Alvarado scoring was done for all patients. Histopathology
reports were sought from the pathology laboratory and finally the results were
analysed.
Result: A total of 85 patients were studied. Male to female ratio was 1.3:1. Age
ranged from 6 to 64 years. Mean duration of onset of symptoms to presentation was
4.56 days (range of <1 – 21 days). Commonest signs and symptoms were right lower
quadrant tenderness, right lower quadrant pain and nausea/vomiting in 90.6% (n=77),
84.7% (n=72) and 78.8% (n=67) patients respectively. Sensitivity and specificity of
the ultrasound were 70.5% and 30% respectively. Majority, (81.2%, n=69) had
Alvarado score of ≥ 4, of which, 90.6% (n=58) had appendicitis. In the 0 - 3 Alvarado
score group, majority (62.5%, n=10) had no appendicitis. The sensitivity and
specificity of Alvarado score from ≥ 4 was 90.6% and 47.6% respectively. The
overall negative appendectomy rate was 24.7%.
Conclusion: Alvarado score is an accurate tool in the diagnosis of acute appendicitis.
Ultrasonography is not as accurate as Alvarado score and cannot be relied upon on its
own to make a diagnosis of acute appendicitis.
Recommendation: Application of Alvarado score should be made the standard
operating procedure in diagnosing acute appendicitis at MTRH. Ultrasound should
not be heavily relied upon in diagnosis of acute appendicitis.
