Follow-Up Chest X-Rays After Pneumonia?

[Argirios Argiriou]

Allan S. Brett, MD  reviewing Tang KL et al. Arch Intern Med 2011 Jul 11

Follow-up imaging probably can be limited to older patients.

Older guidelines recommended routine follow-up chest x-rays at about 6 weeks after episodes of community-acquired pneumonia, presumably to screen for malignancy after an acute infiltrate has cleared. More recent U.S. guidelines don't address this issue (Clin Infect Dis 2007; 44(Suppl 2):S27), and a recent U.K. guideline recommends this practice only for patients with persistent symptoms or those “at higher risk of underlying malignancy (especially smokers and those aged >50 years)” (Thorax 2009; 64(Suppl 3):iii1).

In this population-based cohort study, Canadian researchers identified all 3398 patients without known cancer who received inpatient or outpatient treatment for pneumonia between 2000 and 2002 in metropolitan Edmonton. The incidence of newly diagnosed lung cancer was 1.1% at 90 days and 1.7% at 1 year. Only 40% of patients had follow-up chest x-rays performed within 90 days. All but 1 of the 57 patients in whom cancer was diagnosed within 1 year were 50 or older; thus, the authors conclude that routine follow-up chest x-rays should be restricted to people in that age group.

COMMENT
Because less than half the patients underwent follow-up chest x-rays and, because this study was not a randomized comparison of imaging versus no imaging, the benefit of routine radiography after pneumonia remains unclear. However, the low 1-year incidence of lung cancer provides reassurance that a selective approach — limiting follow-up chest x-rays to middle-aged and older adults — is reasonable. Obviously, patients of any age who remain symptomatic also should undergo follow-up imaging. (Read the case history of a pneumonia patient, and decide if you would order a follow-up x-ray.)

CITATION(S):
Tang KL et al. Incidence, correlates, and chest radiographic yield of new lung cancer diagnosis in 3398 patients with pneumonia. Arch Intern Med 2011 Jul 11; 171:1193. (Δεν είναι ορατοί οι σύνδεσμοι (links). Εγγραφή ή Είσοδος)