Mathematical Examination of Dual Individualization Principles (III): Development of a Scoring System for Pneumonia Staging and Quantitation of Response to Antibiotics: Results in Cefmenoxime-Treated Patients

Abstract

OBJECTIVE:

In order to quantitatively express the important, time-related aspects of response to antimicrobial therapy in patients with pneumonia, we required validated measures of the time course of events during the infection. To quantitate the changes in clinical status in relation to changes in cultures, we developed a scoring system to be used for patient assessment during therapy.

DESIGN:

Retrospective data collection, prospective analysis of factors.

SETTING:

Intensive care unit, Millard Fillmore Hospital.

PATIENTS:

Twenty-eight patients with nosocomial pneumonia.

MAIN OUTCOME MEASURES:

Clinical parameters were assessed daily for the duration of antimicrobial therapy. Using linear regression, the rate of clinical change in each patient treated was quantified. Eradication of the pathogen was determined by serial cultures of the infection site.

RESULTS:

Seventeen of the patients demonstrated eradication of the organism, and 11 demonstrated persistence of the pathogen (7 were considered colonization). The system described the patients at baseline in that the mean baseline scores were similar in both groups of patients (p=0.79). Patients in whom the pathogen was eradicated showed a rate of clinical improvement significantly different from those who had persistence of the organism (p=0.04). In patients demonstrating eradication, the time to eradication inversely correlated with the rate of clinical improvement (p<0.05). Of the ten parameters descriptive of the disease, those most sensitive to change after eradication of bacteria were body temperature, bacterial Gram stain, white blood cell Gram stain, and volume of sputum.

CONCLUSIONS:

In this set of pneumonia patients, the scoring system effectively quantified both baseline and time-related changes in clinical status. The system distinguished between the clinical course of the patient with organism eradication versus organism persistence. A shorter time to eradication was associated with a better clinical response. Prospective study of the system will determine its sensitivity.