[Critical evaluation and predictive value of clinical presentation in out-patients with acute community-acquired pneumonia].
Diagnostic probability of community-acquired pneumonia (CAP) depends on data related to age and clinical and radiological findings. The critical evaluation of data in the literature leads to the following conclusions: 1) the prevalence of CAP in a given population with acute respiratory disease is 5% in outpatients and 10% in an emergency care unit. This could be as low as 2% in young people and even higher than 40% in hospitalized elderly patients; 2) the collection of clinical data is linked to the way the patient is examined and to the expertise of the clinician. The absolute lack of "vital signs" has a good negative predictive value in CAP; presence of unilateral crackles has a good positive predictive value; 3) there is a wide range of X-ray abnormalities: localized alveolar opacities; interstitial opacities, limited of diffused. The greatest radiological difficulties are encountered in old people with disorders including chronic respiratory or cardiac opacities and as a consequence of the high prevalence of bronchopneumonia episodes at this age; 4) among patients with lower respiratory tract (LRT) infections, the blood levels of leukocytes, CRP and procalcitonine are higher in CAP patients, mainly when their disease has a bacterial origin. Since you have not a threshold value reliably demonstrated in large populations with LRT infections or acute respiratory disease, presence or absence of these parameters could only be taken as a slight hint for a CAP diagnosis.
Mayaud
C
C
Service de pneumologie et de réanimation respiratoire, hôpital Tenon, 4, rue de la Chine, 75020 Paris, France. charles.mayaud@tnn.aphp.fr
Fartoukh
M
M
Prigent
H
H
Parrot
A
A
Cadranel
J
J
D000208:Acute Disease; D017714:Community-Acquired Infections / Q000188:drug therapy* / Q000453:epidemiology; D006801:Humans; D010045:Outpatients; D010808:Physical Examination; D011014:Pneumonia / Q000188:drug therapy* / Q000453:epidemiology; D011237:Predictive Value of Tests; D015995:Prevalence; D014481:United States / Q000453:epidemiology