Hyponatremia Is a Specific Marker of Perforation in Sigmoid Diverticulitis or Appendicitis in Patients Older Than 50 Years

Table 3

Specificities, sensitivities, percentage of correctly classified patients, and the likelihood ratios of the markers correlating significantly with infectious colon perforation.

Marker	Sensitivity	Specificity	Correctly classified	Likelihood ratio +	Likelihood ratio −
Fever (>37.5°C)	28%	87%	66%	2.2	0.8
Tachycardia (>100 bpm)	21%	91%	65%	2.4	0.9
Hyponatremia (<136 mmol/L)	31%	79%	61%	1.5	0.9
Markedly elevated CRP (>50 mg/L)	80%	40%	54%	1.3	0.5
Leukocytosis (>10/nL)	74%	39%	51%	1.2	0.7