Immunonutritional status predicts poor prognosis of active pulmonary tuberculosis

<b>Background:</b> The combined nutritional and immunological indices have been used in oncology to determine the indication for surgery and to predict prognosis, but there are few reports on clinical usefulness in tuberculosis. This study aimed to evaluate the relationship between immunonutritional status and prognosis in active tuberculosis. <b>Methods:</b> We retrospectively analysed 1000 consecutive patients with culture-positive tuberculosis at Shizuoka General Hospital between January 2011 and December 2020. The associations between the prognosis and immunonutritional indices, such as prognostic nutritional index (PNI), CRP to albumin ratio (CAR), and procalcitonin to albumin ratio (PAR), were evaluated by ROC analysis. PNI was calculated as follows: 10 x serum albumin (g/dL) + 0.005 x total lymphocyte count (per millimeter). <b>Results:</b> The mean age of the patients was 74.3 years, and 196 patients died during hospitalization. ROC analysis showed that the AUC of PNI was 0.842 (cut off 31.8, sensitivity 67.3%, specificity 88.3%) and that of PAR was 0.840 (cut off 0.046, sensitivity 72.0%, specificity 84.5%). These combined indices had a higher prognostic value than single index, such as albumin and peripheral blood lymphocyte count alone. <b>Conclusion:</b> Immunonutritional indices combining serum albumin, procalcitonin, and peripheral blood lymphocyte count are useful in predicting the prognosis of active pulmonary tuberculosis. ROC analysis for predicting in-hospital death.