Persistence of lung inflammation and lung cytokines with high-resolution CT abnormalities during recovery from SARS.
BACKGROUND
During the acute phase of severe acute respiratory syndrome (SARS), mononuclear cells infiltration, alveolar cell desquamation and hyaline membrane formation have been described, together with dysregulation of plasma cytokine levels. Persistent high-resolution computed tomography (HRCT) abnormalities occur in SARS patients up to 40 days after recovery.


METHODS
To determine further the time course of recovery of lung inflammation, we investigated the HRCT and inflammatory profiles, and coronavirus persistence in bronchoalveolar lavage fluid (BALF) of 12 patients at recovery at 60 and 90 days.


RESULTS
At 60 days, compared to normal controls, SARS patients had increased cellularity of BALF with increased alveolar macrophages (AM) and CD8 cells. HRCT scores were increased and correlated with T-cell numbers and their subpopulations, and inversely with CD4/CD8 ratio. TNF-alpha, IL-6, IL-8, RANTES and MCP-1 levels were increased. Viral particles in AM were detected by electron microscopy in 7 of 12 SARS patients with high HRCT score. On day 90, HRCT scores improved significantly in 10 of 12 patients, with normalization of BALF cell counts in 6 of 12 patients with repeat bronchoscopy. Pulse steroid therapy and prolonged fever were two independent factors associated with delayed resolution of pneumonitis, in this non-randomized, retrospective analysis.


CONCLUSIONS
Resolution of pneumonitis is delayed in some patients during SARS recovery and may be associated with delayed clearance of coronavirus, Complete resolution may occur by 90 days or later.
Wang
Chun-Hua
CH
Department of Thoracic Medicine II, Chang Gung Memorial Hospital, Taipei, Taiwan. wchunhua@ms7.hinet.net
Liu
Chien-Ying
CY
Wan
Yung-Liang
YL
Chou
Chun-Liang
CL
Huang
Kuo-Hsiung
KH
Lin
Horng-Chyuan
HC
Lin
Shu-Min
SM
Lin
Tzou-Yien
TY
Chung
Kian Fan
KF
Kuo
Han-Pin
HP
D000293:Adolescent; D000328:Adult; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology / Q000382:microbiology; D016207:Cytokines / Q000276:immunology*; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging / Q000276:immunology* / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000175:diagnosis* / Q000276:immunology* / Q000382:microbiology; D020127:Recovery of Function / Q000276:immunology; D012189:Retrospective Studies; D045473:Severe acute respiratory syndrome-related coronavirus / Q000302:isolation & purification; D045169:Severe Acute Respiratory Syndrome / Q000175:diagnosis* / Q000276:immunology* / Q000382:microbiology; D013997:Time Factors; D014057:Tomography, X-Ray Computed
D016207:Cytokines