Citation: Vasconcelos A, Rodrigues B, Ferreira P. “Milking” the way to diagnosis. J Clin Images Med Case Rep. 2022; 3(3): 1759.

Description

A 43-year-old non-smoker man presented to the emergency department with exertional dyspnoea and left pleuritic pain for 3 days. He denied fever or cough. He had history of pulmonary embolism, deep venous thrombosis and multiple opportunistic infections. At presentation, his oxygen saturation was 94% with venturi mask at 31% and lung auscultation showed basal crackles. He had no signs of peripheral oedema or deep venous thrombosis. Inflammatory parameters were within normal range. High-resolution chest computed tomography showed diffuse ground-glass opacities with interlobular and intralobular septal thickening — a pattern described as “crazy paving” (Panel A). Bronchoscopy yielded milky appearing lavage fluid (Panel B) and pathological testing revealed proteinaceous material positive on periodic acid–Schiff staining. These findings confirmed a diagnosis of pulmonary alveolar proteinosis (PAP). He underwent volume lavage of both lungs sequentially. At 6-month follow-up, he still maintained substantial improvement, with oxygen saturation of 94% in ambient air. PAP is a rare pulmonary disease caused by impaired surfactant turnover [1]. Although the crazy paving pattern is often associated with PAP [1], it’s not specific and can be seen in other conditions, including acute respiratory distress syndrome, pulmonary haemorrhage, organizing pneumonia, lipoid pneumonia and infections like Pneumocystis jirovecii [2] and SARS-CoV-2 pneumonia.

Figure 1: A) High-resolution chest computed tomography showed diffuse ground-glass opacities with interlobular and intralobular septal thickening — a pattern described as “crazy paving” (Panel A). B) Bronchoscopy yielded milky appearing lavage fluid and pathological testing revealed proteinaceous material positive on periodic acid–Schiff staining.

References

1. Borie R, Danel C, Debray MP, Taille C, et al. Pulmonary alveolar Proteinosis. Eur Respir Review. 2011; 20: 98-107. DOI: 10.1183/09059180.00001311
2. Radiopedia.org. 2020. Crazy Paving | Radiology Reference Article | Radiopedia.org | [online]. Available at: http://radiopedia.org/articles/crazy-paving [Accessed 3 June 2020]