Abstract
Purpose
This paper describes the radiological and clinical findings identified in a group of patients with H1N1 influenza.
Materials and methods
Between May and mid-November 2009, 3,649 patients with suspected H1N1 influenza presented to our hospital. Our study population comprised 167 (91 male, 76 female patients, age range 11 months to 82 years; mean age 29 years) out of 1,896 patients with throat swab positive for H1N1 and clinical and laboratory findings indicative of viral influenza. All 167 patients were studied by chest X-ray (CXR), and 20 patients with positive CXR and worsening clinical condition also underwent computed tomography (CT). The following findings were evaluated on both modalities: interstitial reticulation (IR), nodules (N), ground-glass opacities (GGO), consolidations (CONS), bacterial superinfection and pulmonary complications.
Results
Ninety of 167 patients had positive CXR results. Abnormalities identified on CXR, variously combined and distributed, were as follows: 53 IR, 5 N, 13 GGO, 50 CONS; the predominant combination was represented by six GGO with CONS. Of the 20 CXR-positive cases also studied by CT, 17 showed pathological findings. The abnormalities identified on CT, variously combined and distributed, were as follows: 14 IR, 2 N, 5 GGO; the predominant combination was 10 GGO with CONS. Despite the differences between the two modalities, the principle radiological findings of bacterial superinfection were tree-in-bud pattern, consolidation with air bronchogram, and pleural and pericardial effusion. Fifteen of the 20 patients studied by both CXR and chest CT showed respiratory complications with bilateral and diffuse CONS on CXR and CT. Six of 15 died: 4/6 of acute respiratory distress syndrome and 2/6 of multiple organ failure.
Conclusions
Our study describes the radiological and clinical characteristics of a large population of patients affected by H1N1 influenza. CXR and chest CT identified the site and extent of the pulmonary lesions and documented signs of bacterial superinfection and pulmonary complications.
Riassunto
Obiettivo
Lo scopo di questo lavoro è stato quello di definire il quadro radiologico e clinico di un gruppo di pazienti con influenza H1N1.
Materiali e metodi
Un totale di 3649 pazienti con sospetta H1N1 si sono presentati al nostro presidio ospedaliero tra maggio 2009 e metà novembre 2009. Centosessantasette su 1896 casi risultati positivi al tampone faringeo per H1N1 (91 M, 76 F, range età 11 mesi-82 anni, età media 29 anni), con alterazioni clinico-laboratoristiche di influenza virale, hanno costituito la popolazione del nostro studio. Tutti i 167 pazienti hanno eseguito radiografia (Rx) del torace; per le più gravi condizioni cliniche, 20 casi positivi alla Rx del torace hanno effettuato tomografia computerizzata (TC) del torace. Abbiamo identificato in ambedue le metodiche: reticolazione interstiziale (RI), noduli (N), opacità ground glass (OGG), consolidamenti (CM), segni di sovrainfezione batterica e complicanze.
Risultati
Novanta su 167 casi mostravano reperti radiografici positivi. Le lesioni polmonari identificate alla Rx, variamente associate e distribuite, sono state: 53 RI, 5 N, 13 OGG, 50 CM; 6 OGG con CM rappresentavano l’associazione predominante. Dei 20 pazienti positivi alla Rx del torace e sottoposti ad esame TC, 17 mostravano reperti TC positivi. Le lesioni polmonari identificate alla TC, variamente associate e distribuite, sono state: 14 RI, 2 N, 5 OGG; 10 OGG con CM rappresentavano l’associazione predominante. Sebbene differentemente identificati in Rx e TC, i segni di sovrainfezione batterica più frequenti sono stati tree-in-bud, CM con broncogramma aereo, versamento pleurico e pericardico. Dei 20 pazienti studiati con Rx e TC, 15 hanno presentato complicanze respiratorie con un quadro Rx e TC di OGG e CM diffusi e bilaterali. Sei/15 sono deceduti: 4/6 per acute respiratory distress syndrome (ARDS), 2/6 per multiple organ failure (MOF).
Conclusioni
Il nostro studio ha delineato le caratteristiche radiologiche e cliniche di un’ampia popolazione di pazienti con influenza H1N1. La Rx e la TC del torace hanno identificato sede ed estensione delle lesioni polmonari, documentando i segni di sovrainfezione batterica e le complicanze polmonari.
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Coppola, M., Porto, A., De Santo, D. et al. Influenza A virus: radiological and clinical findings of patients hospitalised for pandemic H1N1 influenza. Radiol med 116, 706–719 (2011). https://doi.org/10.1007/s11547-011-0622-0
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DOI: https://doi.org/10.1007/s11547-011-0622-0