A patient has an undetectable CH50 but a normal AH50. Which defect is most consistent with this screening pattern?
1A component unique to the classical pathway✓ 정답
2A terminal complement component shared by both pathways
3Complete absence of all immunoglobulins
4A defect limited to neutrophil myeloperoxidase
해설
CH50 assesses the classical pathway through the terminal pathway, whereas AH50 assesses the alternative pathway. Absent CH50 with preserved AH50 points toward an early classical-pathway component defect.