Objective: To investigate the diagnostic and treatment experience of a Costello syndrome case

so as to arouse pediatric practitioner’s concern of the disease

make early diagnosis

reasonable treatment and improve prognosis. Methods: The clinical data of a case of Costello syndrome were retrospectively analyzed and the related literatures were reviewed. Results: Atrial arrhythmia

ventilator dependence

special facial and skin appearance were the main clinical manifestations of a prematurity transferred to Shenzhen Children’s Hospital due to “dyspnea and abdominal distension for 42 days”. A heterozygous novel de novo pathogenic variant (c. 34gG> A) in HRAS was detected by high-throughput sequencing of the whole exome. Then Costello syndrome was diagnosed. Digoxin

propafenone

propranolol

sotalol and other anti-arrhythmic drugs were administrated to control the arrhythmia. The ventricular rate was improved slightly and the ventilator was successfully evacuated. However

due to poor prognosis

family members gave up treatment

and one day after discharge

the patient had frequent atrial premature contractions and died of cardiogenic shock. Conclusion: Gene diagnosis

ECG

and cardiac color doppler ultrasound are essential for children with arrhythmia

feeding difficulties

special facial and skin appearance. Antiarrhythmic treatment should be adjusted according to heart rate

and cardio-involvement is the determinant of prognosis.