Trends in Blood Mosaicism and Clinical Phenotype Score in Patients with Beckwith-Wiedemann Syndrome Evaluated for Tongue Reduction Surgery.

INTRODUCTION: Most patients with Beckwith-Wiedemann syndrome (BWS) have macroglossia with some requiring tongue reduction surgery (TRS). This study reports correlations between levels of affected cells (mosaicism) and BWS clinical score in patients evaluated for TRS. We also show correlations of clinical score and mosaicism with obstructive sleep apnea (OSA) severity.

METHODS: Blood mosaicism levels and BWS clinical score were recorded in patients with macroglossia referred to plastic surgery for evaluation. Associations among blood mosaicism, BWS clinical score, TRS, and OSA were assessed with appropriate statistics.

RESULTS: Of the 225 patients included, BWS blood testing was available in 128 (56.9%). Mosaicism levels were higher in those who underwent TRS compared to those who did not (85.9 85.9 (56.5-95.9)% vs. 29.7 (2.8-73.1)%, p<0.001). BWS clinical score was also higher in those requiring TRS (9.0 (8.0-11.0) versus 7.0 (6.0-9.0), p<0.001). There was a positive correlation between clinical score and obstructive apnea-hypopnea index (r=0.320, p=0.011). Receiver operating characteristic curve analysis showed a clinical score ≥11 had 100% specificity and 36.4% sensitivity for detecting patients requiring TRS. Blood mosaicism ≥80% had 63.6% sensitivity and 83.6% specificity for predicting surgery. A combined criteria of BWS clinical score ≥11 or mosaicism ≥80% had 72.7% sensitivity and 83.6% specificity for predicting TRS.

CONCLUSION: Blood mosaicism levels and higher BWS clinical scores appear associated with a greater frequency of having surgery in patients with macroglossia referred for surgical evaluation. Elevations in BWS clinical scoring are associated with increased OSA severity while increased blood mosaicism is not.