High Resolution Computerized Tomography Evaluation of Infl uenza H1N1 Infection

  • Sonali Salvi Assistant Professor, Department of Medicine
  • Dileep Kadam Professor and Head, Department of Medicine
  • Minakshi Gajbhiye Professor and Head, Department of Radiology
  • Shephali Pawar Associate Professor, Department of Radiology
  • Ajay Chandanwale Dean, B. J. Government Medical College
Keywords: Infl uenza A virus, H1N1 subtype, Pneumonia, Radiography, Tomography computed

Abstract

Background: H1N1 infection presents with features of predominantly bilateral pneumonia. The fi ndings on plain chest
radiograph (CXR) in these patients often fail to correlate with the extensive clinical fi ndings. The study was carried out to bring
to light the array of features that can be observed on a computerized tomography (CT) of the thorax.
Methods: All throat swab culture verifi ed H1N1 infected patients admitted to the Department of Medicine, Sassoon General
Hospital between August 2012 and April 2013, who underwent frontal CXR within 24 h of presentation were subjected to high
resolution CT of thorax (HRCT). There were ten cases in which HRCT of thorax was performed. These cases were analyzed
in terms of their clinical, laboratory and radiological fi ndings.
Results: Clinical profi le of these patients matched the presentation of acute lower respiratory infection, and seven of ten
patients had underlying risk factors such as diabetes, pregnancy, chronic obstructive lung disease and rheumatic valvular heart
disease. In all ten patients, HRCT revealed greater number of fi ndings. Lower zones were predominantly involved. Bilateral
presentation was seen in eight cases. Consolidation (n = 7) and bilateral ground glass opacities (n = 3), constituted the most
common fi ndings. Pleural thickening (n = 2), septal thickening (n = 2), air trapping (n = 2), mediastinal adenopathy (n = 1),
pleural effusion (n = 1), sub-pleural nodules (n = 2) and organizing pneumonia (n = 1) were other notable observations. Chest
radiograph (in comparison to HRCT), failed to reveal these heterogenous abnormalities.
Conclusion: HRCT of thorax had greater co-relation with clinical fi ndings in H1N1 infection than plain CXR.

Author Biographies

Sonali Salvi, Assistant Professor, Department of Medicine

B J Government Medical College, Pune, Maharashtra, India

Dileep Kadam, Professor and Head, Department of Medicine

B J Government Medical College, Pune, Maharashtra, India

Minakshi Gajbhiye, Professor and Head, Department of Radiology

B J Government Medical College, Pune, Maharashtra, India

Shephali Pawar, Associate Professor, Department of Radiology

B J Government Medical College, Pune, Maharashtra, India

Ajay Chandanwale, Dean, B. J. Government Medical College

Pune, Maharashtra, India

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Published
2021-10-09