Accuracy of clinical presentation for differentiating bacterial from viral meningitis in adults: a multivariate approach

OBJECTIVE

To determine whether bacterial (BM) and viral (VM) meningitis can be differentiated based on initial clinical presentation.

DESIGN AND SETTING

Retrospective cohort study in a medical emergency department and intensive care unit in a university hospital.

PATIENTS

144 adults, including 90 with confirmed BM and 54 unpretreated VM.

MEASUREMENTS AND RESULTS

Symptoms, examination findings, paraclinical data, and clinical outcome were assessed. Severity was defined by the presence at referral of one of the following criteria: altered consciousness, seizures, focal neurological findings, and shock. After univariate analyses we performed stepwise logistic regression to determine predictors for BM available at referral (except for CSF Gram stain) and logistic regression using previously validated CSF cutoffs. Univariate methods identified the presence of one sign of severity as the most important predictor for BM (sensitivity 0.989, specificity 0.981, positive predictive value 0.989, negative predictive value 0.981, odds ratio 4,770) and showed that CSF results differ in BM and in VM (except for CSF glucose). Logistic regression analysis revealed severity and CSF absolute neutrophil count as the two predictors of BM (R2=0.876). Logistic analysis showed that BM was related to severity (beta=6.46+/-1.27) and a CSF absolute neutrophil count above 1,000/mm3 whereas CSF glucose below 2 mmol/l and CSF protein higher than 2 g/l were not predictive.

CONCLUSIONS

The presence of at least one sign of severity at referral and a CSF absolute neutrophil count above 1,000/mm3 mm are predictive of BM.

Hypothermia with indoor occurrence is associated with a worse outcome

OBJECTIVE

To describe patients admitted to intensive care unit (ICU) for hypothermia, evaluate prognostic factors, and test the hypothesis that patients found indoors have a worse outcome.

DESIGN AND SETTING

Retrospective clinical investigation in a medical ICU.

PATIENTS

Eighty-one consecutive patients admitted to ICU, with a body temperature of 35 degrees C or lower and rewarmed passively or with minimally invasive techniques, over a 17-year period.

MEASUREMENTS AND RESULTS

Patients were analyzed by age, gender, and causes of hypothermia and split into two groups (indoors and outdoors), according to the location where hypothermia occurred. Prognostic factors were determined by univariate method and stepwise logistic regression. The major complications were acute renal failure (43 %), aspiration pneumonia (22 %), rhabdomyolysis (22 %), and acute respiratory distress syndrome (12%). Principal comorbidities in the outdoor patients (21%) were alcohol and drug intoxication, and those in the indoor patients (79 %) were sepsis and neuropsychiatric disorders. Stepwise logistic regression identified two variables predictive of death: illness severity at admission (SAPS II > or = 40) and the location where hypothermia occurred (indoors versus outdoors).

CONCLUSIONS

With equivalent body temperature, patients found indoors were more severely affected and died more frequently than those found outdoors.