Cerebral fat embolism with turbid urine as the initial sign

ABSTRACT

Background

Cerebral fat embolism (CFE) is a rare but potentially fatal complication that can occur after long bone fractures. It represents one subcategory of fat embolisms (FE). Diagnosing CFE can be challenging due to its variable and nonspecific clinical manifestations. We report a case of CFE initially presenting with turbid urine, highlighting an often neglected sign.

Case presentation

A 69-year-old male was admitted after a traffic accident resulting in bilateral femoral fractures. Sixteen hours post-admission, grossly turbid urine was noted but received no special attention. Four hours later, he developed rapid deterioration of consciousness and respiratory distress. Neurological examination revealed increased upper limb muscle tone and absent voluntary movements of lower limbs. Brain MRI demonstrated a ‘starfield pattern’ of diffuse punctate lesions, pathognomonic for CFE. Urine microscopy confirmed abundant fat droplets. Supportive treatment and fracture fixation were performed. The patient regained consciousness after 3 months but had residual dysphasia and limb dyskinesia.

Conclusion

CFE can present with isolated lipiduria preceding overt neurological or respiratory manifestations. Heightened awareness of this subtle sign in high-risk patients is crucial for early diagnosis and intervention. Prompt urine screening and neuroimaging should be considered when gross lipiduria occurs after long bone fractures.

KEYWORDS:

• Cerebral fat embolism syndrome
• Lipiduria
• Long bone fracture
• Star-field pattern
• Magnetic resonance imaging

Acknowledgments

The author thanks professor Lubin Gao for his guidance during the treatment of the case, and thanks Engineer Nan Jia for his assistance in imaging retrieval.

Disclosure statement

No potential conflict of interest was reported by the author(s).