[Study on intractable factors in urinary tract infections--multiple regression analysis].

Intractable complicated urinary tract infections (UTI) are caused by host and/or bacterial factors which predispose to persistent infections and recurrent infections. It is still unknown what kind of factors are responsible for the intractable complicated UTI. With the increase of compromised host or cases with complicated UTI, the factors involved in intractable and recurrent UTI are diversified. Accurate diagnosis of the factors affecting the therapeutic effect will have more importance. The factors affecting the therapeutic effect was subjected to multiple regression analysis from both aspects of underlying disease in the urinary tract (complicated factors) and systemic conditions (compromised factors) in one hundred and ninety patients of complicated UTI admitted to our clinic. Sex, presence or absence of hydronephrosis and indwelling catheter and volume of residual urine as complicated factors and age, serum creatine value, peripheral neutrophil count, peripheral lymphocyte count, diabetic or not, whether the patient underwent major operation within 1 week or not, and serum albumin value, an indicator of malnutrition, as compromised factors were analyzed by multiple regression analysis. The presence of indwelling catheter, residual urine more than 50 ml and hypoalbuminemia less than 3 g/dl were the most determinant of the clinical efficacy in cases with complicated UTI. Interestingly, presence of residual urine more than 50 ml is considered an equally intractable factor with the presence of indwelling catheter. These factors proved to be important also as recurrent factors. In the host with these factors, UTI are often caused by resistant bacteria and indicated to be intractable also bacteriologically.