When Acute Respiratory Distress Syndrome is not ARDS

Excerpt

A 58-year-old male with Ehler–Danlos syndrome was referred to our hospital for admission to respiratory intensive care unit (RICU) as he presented with fever (38.0°C) followed by an extremely rapid onset of acute respiratory failure with a radiological pattern of acute respiratory distress syndrome (ARDS) on high-resolution computed tomography (HRCT) (Fig. 1). In the days prior to admission, he had developed progressive cognitive and motor deficits with associated mild dysphagia and swallowing impairment due to considerable enlargement of a partially thrombosed aneurysm in the basilar artery. No recent chest radiographic images were available. After RICU admission the patient was treated with invasive mechanical ventilation. Since acute respiratory infection was suspected, he underwent fiberoptic bronchoscopy (FOB) with bronchoalveolar lavage (BAL) whose sample presented with a milky appearance. A few minutes after the procedure, the different components of the sample started separating into fluid and corpuscolated parts (Fig. 2). BAL fluid resulted negative on microbiological analysis, while cytological examination showed multiple lipid-laden macrophages. Based on BAL fluid evidence, we reviewed the patient’s recent medical history and we learned that during the previous week he had been aspirating a minimum quantity of petroleum jelly used as a laxative to treat a form of transient constipation. The progressive neurological impairment due to vascular disease had probably favored the aspiration process. On this ground, the diagnosis of ARDS-like exogenous lipoid pneumonia was made. Despite a wide range of reported manifestations [1], acute respiratory failure requiring RICU admission and mechanical ventilation is a very rare presentation of the disease and it is usually due to a massive aspiration [2]. In our case, petroleum jelly served as a laxative for an intercurrent constipation and was used for only a week. We conclude that although a rare occurrence, even low amounts of oil-based laxatives may increase the risk of ARDS-like life-threatening lipoid pneumonia in patients with neurological impairment.

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