Prospective case-control study of role of infection in patients who reconsult after initial antibiotic treatment for lower respiratory tract infection in primary care.
OBJECTIVE
To assess direct and indirect evidence of active infection which may benefit from further antibiotics in adults who reconsult within 4 weeks of initial antibiotic management of acute lower respiratory tract infection in primary care.


METHODS
Observational study with a nested case-control group.


METHODS
Two suburban general practices in Arnold, Nottingham, over 7 winter months.


METHODS
367 adults aged 16 years and over fulfilling a definition of lower respiratory tract infection and treated with antibiotics. 74 (20%) patients who reconsulted within 4 weeks for the same symptoms and 82 "control" patients who did not were investigated in detail at fallow up.


METHODS
Direct and indirect evidence of active infection at the time of the reconsultation or the follow up visit with the research nurse for the controls. Investigations performed included sputum culture, pneumococcal antigen detection, serial serology for viral and atypical pathogens and C reactive protein, throat swabs for detecting viral and atypical pathogens by culture and polymerase chain reaction, and chest radiographs.


RESULTS
Demographic and clinical features of the groups were similar. Two thirds of the 74 patients who reconsulted received another antibiotic because the general practitioner suspected continuing infection. Any evidence of infection warranting antibiotic treatment was uncommon at reconsultation. The findings for the two groups were similar for the occurrence of identified pathogens; chest x ray changes of infection (present in 13%); and C reactive protein concentrations, which had nearly all fallen towards normal. Only three patients in the reconsultation group had concentrations > or = 40 mg/l. Pathogens identified at follow up in the 156 patients in both groups included ampicillin sensitive bacteria in six. Atypical infections diagnosed in 27 (Chlamydia pneumoniae in 22) and viral infections in 54 had probably been present at the initial presentation.


CONCLUSIONS
Our study suggests that active infection, which may benefit from further antibiotics, is uncommon in patients who reconsult after a lower respiratory tract infection, and a repeat antibiotic prescription should be the exception rather than the rule. Other factors, such as patients' perception of their illness, may be more important than disease and infection in their decision to reconsult.
Macfarlane
J
J
Respiratory Infection Unit, Nottingham City Hospital.
Prewett
J
J
Rose
D
D
Gard
P
P
Cunningham
R
R
Saikku
P
P
Euden
S
S
Myint
S
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001424:Bacterial Infections / Q000188:drug therapy / Q000378:metabolism; D002097:C-Reactive Protein / Q000378:metabolism; D016022:Case-Control Studies; D005194:Family Practice; D006801:Humans; D008875:Middle Aged; D010342:Patient Acceptance of Health Care; D011446:Prospective Studies; D012008:Recurrence; D012141:Respiratory Tract Infections / Q000188:drug therapy* / Q000378:metabolism; D014777:Virus Diseases / Q000188:drug therapy
D000900:Anti-Bacterial Agents; D002097:C-Reactive Protein