Case Report: Atypical posttraumatic fat embolism syndrome: a case of rapidly progressive respiratory failure precipitated by a finger crush injury.

Background: Fat embolism syndrome (FES) is classically associated with long bone fractures; however, digital crush injuries are an extremely rare precipitating factor. Obesity has been identified as an independent risk factor for the development of FES. The potential for rapid disease progression within 12 h of injury necessitates a high index of clinical suspicion. Case summary: A 43-year-old obese male underwent surgical debridement for crush injuries to his left index and thumb fingers. Twelve hours postoperatively, he developed exertional chest tightness. As the disease progressed, escalation from non-invasive to invasive mechanical ventilation became necessary. FES was confirmed by the detection of floating fat droplets and Oil Red O-positive lipid-laden macrophages in bronchoalveolar lavage fluid. After corticosteroid and fluid therapy, pulmonary infiltrates improved markedly, and the patient was successfully weaned from ventilation and extubated on day 7. Conclusions: This case confirms the diagnostic utility of bronchoalveolar lavage in conjunction with Oil Red O staining for rapid FES diagnosis, broadens the etiological spectrum to include atypical injuries of the short bones, and underscores the necessity of maintaining a high index of suspicion for FES in obese patients presenting with unexplained respiratory failure following finger crush injuries, thereby highlighting that early recognition and timely intervention are critical for improving prognosis.