Predictors of Severity in Soft Tissue Infections - A Nested Case Control Study

Soft tissue infections when not identified and treated on time, leads to severe morbidity and mortality. Various factors are mentioned in literature to predict the severity of the infection. They are not universal and is based on retrospective studies. Hence, we proposed this prospective study to assess the various parameters that predicts the severity in patients with soft tissue infections of the lower limb. A nested case control study was designed with a sample size of fifty-five in each arm. Patients were recruited on accrual basis and based on the outcome they were grouped under one of the two arms: non mortality, non-morbidity arm and mortality, morbidity arm. From the data collected, univariate and multivariate analysis were done to find significant variables predicting morbidity and mortality. The significant variables that predict morbidity in patients with soft tissue infections are Neutrophilia (p-0.079) (OR 1.06, CI 0.99 - 1.14), Hyponatremia (p-0.008) (OR 0.84, CI 0.74 - 0.96) and Fever (p-0.029) (OR 4.30, CI 1.16 - 15.92) at presentation. In patients, who presents to hospital with soft tissue infections of the lower limb, those showing significant neutrophilia (OR 1.06, CI 0.99 - 1.14), hyponatremia (OR 0.84, CI 0.74 - 0.96) and fever at presentation (OR 4.30, CI 1.16 - 15.92) have an increased likelihood of morbidity and mortality. Soft tissue infections have high morbidity if not identified and treated early.Objective variables can help us in early diagnosis and prognostication of the patients with soft tissue infections.