The value of inflammatory indices in the diagnosis of acute appendicitis and prediction of complicated appendicitis: a retrospective study.

BACKGROUND

Acute appendicitis is a common cause of acute abdominal pain, typically treated surgically, although medical management is also an option. Laboratory investigations play a valuable role in diagnosis and predicting prognosis. We aimed to investigate and compare the effectiveness of indices such as the Systemic Immune-Inflammation Index (SII), Systemic Inflammatory Response Index (SIRI), and Pan-Immune-Inflammatory Value (PIV), all derived from complete blood count, in diagnosing acute appendicitis and distinguishing between complicated and uncomplicated cases.

METHODS

We retrospectively analyzed data from 334 patients diagnosed with acute appendicitis and 350 healthy individuals. The SII, SIRI, and PIV parameters were compared between the acute appendicitis group and the healthy group. The SII, SIRI, and PIV parameters were also compared between the complicated and uncomplicated groups.

RESULTS

All three parameters demonstrated good performance in predicting the diagnosis of appendicitis. An SII value above 1,008.43 ( < 0.0001, AUC = 0.707), a SIRI value above 2.60 ( < 0.0001, AUC = 0.743), and a PIV value above 904.85 ( < 0.0001, AUC = 0.726) were found to support the diagnosis of appendicitis. For predicting complicated appendicitis, thresholds were identified as SII values above 2501.13 ( = 0.0012, AUC = 0.634), SIRI values above 7.98 ( = 0.0005, AUC = 0.645), and PIV values above 1,869.66 ( = 0.0012, AUC = 0.635).

CONCLUSIONS

All three indices showed good predictive performance for diagnosing appendicitis and acceptable performance for predicting complicated cases. Among the indices, SIRI was slightly superior to the other two in both scenarios.