목적: 단백질 S 결핍환자에서 발생한 좌안의 망막중심동맥폐쇄를 경험하였기에 보고하고자 한다. 증례요약: 36세 남자가 갑작스런 좌안의 시력저하를 주소로 내원하였다. 고혈압, 당뇨 등의 질환은 없었다. 내원시 교정시력은 우안 1.0, 좌안 광각이었고 좌안의 구심성동공운동장애가 관찰되었다. 안저검사상 좌안에서 후극부의 망막혼탁과 함께 앵두반점을 보였다. 혈액응고이상을 포함한 전반적인 혈액학적 검사를 시행하였다. 일반적인 혈액응고검사상 특이소견은 보이지 않았다. 단백질 C활성, 항트롬빈 III의 활성, 항인지질항체, 항카디오리핀항체는 정상이었으나 단백질 S 활성이 감소되어 있었다. 이에 단백질 S 결핍환자에서 발생한 좌안의 망막중심정맥폐쇄로 진단하였다. 결론: 본 증례와 같이 기저질환을 가지지 않은 젊은 사람에서 망막중심동맥폐쇄가 발생하는 경우 일반적인 혈액응고검사 이외에도 단백질 S와 같은 혈액 응고인자에 대한 검사를 시행해 보는 것이 필요할 것으로 생각된다.

Purpose: To report a case of central retinal artery obstruction (CRAO) caused by protein S deficiency. Case summary: A 36-year-old man presented with acutely reduced visual acuity in the right eye. The patient had no other diseases such as diabetes mellitus or hypertension. The visual acuity was 20/20 in the right eye and light perception in the left eye. Afferent pupillary defect was observed in theleft eye. Fundus examination showed diffuse retinal opacification and a cherry-red spot at the macula. Thus the patient was diagnosed with CRAO in the left eye. There were no abnormal findings on routine hematologic tests including blood coagulation test. Protein C activity, antithrombin III activation, anticardiolipin antibody were within normal limits but protein S activity was decreased. Thus, the patient was diagnosed with CRAO with protein S deficiency. Conclusions: Coagulation factors such as protein S need to be measuredin cases of CRAO in young patients without medical problems.

Purpose: To report a case of central retinal artery obstruction (CRAO) caused by protein S deficiency. Case summary: A 36-year-old man presented with acutely reduced visual acuity in the right eye. The patient had no other diseases such as diabetes mellitus or hypertension. The visual acuity was 20/20 in the right eye and light perception in the left eye. Afferent pupillary defect was observed in theleft eye. Fundus examination showed diffuse retinal opacification and a cherry-red spot at the macula. Thus the patient was diagnosed with CRAO in the left eye. There were no abnormal findings on routine hematologic tests including blood coagulation test. Protein C activity, antithrombin III activation, anticardiolipin antibody were within normal limits but protein S activity was decreased. Thus, the patient was diagnosed with CRAO with protein S deficiency. Conclusions: Coagulation factors such as protein S need to be measuredin cases of CRAO in young patients without medical problems.