Objectives: To evaluate the diagnostic yield of preoperative estimation of serum C-reactive protein
(CRP) and total leucocytic count (TLC) as adjuncts to modified Alvarado score (MAS) for diagnosis of
acute appendicitis (AA) and prediction of cases of complicated appendicitis (CA).
Patients & Methods: The study included 324 patients underwent appendicectomy; all patients underwent
clinical examination and calculation of MAS and had abdominal ultrasonography (US). Blood samples
were taken for estimation of serum CRP and TLC. Patients were categorized according to intraoperative
findings into: CA including those had suppurative, gangrenous and/or perforated appendix, had
appendicular abscess or mass and Uncomplicated appendicitis (UA) included patients had edematous or
normal appendix.
Results: MAS defined 107 patients had score <7 and 217 patients had score of >7 with a mean total score
of 5.62.3; range: 2-9. MAS could predict AA with 71.9% sensitivity, 68.2% specificity, 96%, positive
predictive value (PPV) and 15% negative predictive value (NPV) with accuracy rate of 69.4%. Surgical
exploration defined CA in 213 and UA mill patients. US defined 185 CA cases and 139 UA patients
with 53.1% sensitivity, 35.1% specificity, 61.1% PPV, 28% NPV and 46.9% accuracy rate. TLC
was >10,000 cells/ml in 193 patients, was <10,000 cells/ml in 131 patients. Serum CRP level of >10 mg/1
was defined in 230 patients, while 94 patients had serum CRP of <10 mg/1. Patients had CA had
significantly higher TLC and serum CRP compared to uncomplicated cases. Preoperative leucocytosis
defined CA with sensitivity rate of 71.4%, specificity rate of 61.3%, PPV of 77.9% and NPV of 52.7%
with accuracy rate of 67.9%. Preoperative serum CRP could define CA with sensitivity rate of 83.1%,
specificity rate of 42.3%, PPV of 73.4% and NPV of 56.6% with accuracy rate of 69.1%. ROC curve
analysis defined high Alvarado score, TLC and serum CRP as the most sensitive predictors for CA.
Regression analysis defined high serum CRP as a significant predictor for CA, followed by MAS, high
TLC, US and male gender.
Conclusion: No single diagnostic modality could be used for proper discrimination between cases with
RIF pain. However, preoperative estimation of serum CRP with its high PPV could be used as adjunct to
MAS to improve its NPV so improving home-return decision making; sparing unnecessaiy
appendicectomy and reducing consumption of hospital resources. |
