title: Diagnosis of pneumonia by cultures, bacterial and viral antigen detection tests, and serology with special reference to antibodies against pneumococcal antigens.
abstract: In a prospective study of the etiology of pneumonia 196 adult patients were included. One of the following criteria was required for diagnosis of pneumococcal pneumonia: isolation of pneumococci from blood; isolation from transtracheal aspirate; isolation from sputum or nasopharynx or detection of capsular antigen in sputum in combination with a significant increase in antibodies against at least one pneumococcal antigen (type-specific capsular polysaccharide, C-polysaccharide, pneumolysin); or increase in antibodies against two pneumococcal antigens. Pneumococcal pneumonia was diagnosed in 63 patients (32%). Other diagnoses were nonencapsulated Haemophilus influenzae isolated from transtracheal aspirates, 9; Mycoplasma pneumoniae diagnosed by serology, 17; Chlamydia psittaci, 6; and viral infections, 42. Twenty-two patients (11%) had evidence of infection with more than one agent. The pathogen could not be determined in 70 (36%). Many patients were given antibiotics before admittance to the study, and in some cases a convalescent serum sample was not available.
authors.affiliation: Department of Infectious Diseases and Virology, University of Umeå, Sweden.
authors.forename: L A
authors.initials: LA
authors.lastname: Burman
authors.forename: B
authors.initials: B
authors.lastname: Trollfors
authors.forename: B
authors.initials: B
authors.lastname: Andersson
authors.forename: J
authors.initials: J
authors.lastname: Henrichsen
authors.forename: P
authors.initials: P
authors.lastname: Juto
authors.forename: I
authors.initials: I
authors.lastname: Kallings
authors.forename: T
authors.initials: T
authors.lastname: Lagergård
authors.forename: R
authors.initials: R
authors.lastname: Möllby
authors.forename: R
authors.initials: R
authors.lastname: Norrby
mesh_terms: D000293:Adolescent; D000328:Adult; D000372:Agglutination Tests; D000907:Antibodies, Bacterial / Q000097:blood*; D000942:Antigens, Bacterial / Q000032:analysis*; D006192:Haemophilus Infections / Q000175:diagnosis; D006801:Humans; D009305:Nasopharynx / Q000382:microbiology; D011014:Pneumonia / Q000175:diagnosis* / Q000209:etiology; D011019:Pneumonia, Mycoplasma / Q000175:diagnosis; D011018:Pneumonia, Pneumococcal / Q000175:diagnosis; D011024:Pneumonia, Viral / Q000175:diagnosis; D011446:Prospective Studies; D009956:Psittacosis / Q000175:diagnosis; D013183:Sputum / Q000382:microbiology; D013296:Streptococcus pneumoniae / Q000276:immunology / Q000302:isolation & purification*
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial