Carmel R, Green R, Jacobsen D W, Qian G D
Department of Medicine, University of Southern California School of Medicine, Los Angeles 90033, USA.
Am J Clin Pathol. 1996 Jul;106(1):57-63. doi: 10.1093/ajcp/106.1.57.
Neutrophil hypersegmentation is considered the most sensitive peripheral blood cell marker of cobalamin deficiency. However, its diagnostic value in the mild deficiency states that accompany most low cobalamin levels and its relation to metabolic test of cobalamin status are unknown. The authors compared neutrophil lobe averages and percent neutrophils with 5 or more lobes (%5+ lobes) in 169 subjects with their mean corpuscular volume (MCV) and serum cobalamin, methylmalonic acid (MMA), homocysteine, and folate levels and, in 65 cases, with the deoxyuridine suppression test (dUST). Only 9 subjects had hypersegmentation by lobe average and 20 subjects by %5+ lobes. They were not more often cobalamin-deficient than subjects without hypersegmentation. Moreover, only one of 34 subjects with dUST results diagnostic for cobalamin deficiency had neutrophil hypersegmentation. Both indices of neutrophil segmentation in the 169 subjects correlated significantly with homocysteine levels. They also showed weak inverse correlation with cobalamin levels, but did not correlate with MMA, folate, or MCV values. Cobalamin therapy for 6 months did not significantly change neutrophil lobe averages in 35 subjects with mild deficiency, compared with 8 nondeficient controls, and only marginally improved the %5+ lobes. A surprising, incidental observation was that blacks had significantly greater neutrophil segmentation by both criteria than did whites and others. This difference was unrelated to cobalamin or folate status. Our results indicate that dUST abnormalities precede all morphologic changes of deficiency, including hypersegmentation. Although a tendency exists for neutrophil segmentation to increase very slightly as some serum values, especially homocysteine, start to worsen in mild cobalamin deficiency, the metabolic changes precede overt hypersegmentation. Neutrophil nuclear segmentation is insufficiently sensitive in relation to metabolic evidence of deficiency to be used as a clinical tool in the diagnosis of mild cobalamin deficiency.
中性粒细胞核分叶过多被认为是钴胺素缺乏最敏感的外周血细胞标志物。然而，其在伴随大多数低钴胺素水平的轻度缺乏状态下的诊断价值及其与钴胺素状态代谢检测的关系尚不清楚。作者比较了169名受试者的中性粒细胞叶平均数和5叶或更多叶中性粒细胞百分比（%5+叶）与平均红细胞体积（MCV）、血清钴胺素、甲基丙二酸（MMA）、同型半胱氨酸和叶酸水平，并在65例病例中与脱氧尿苷抑制试验（dUST）进行了比较。只有9名受试者的叶平均数显示核分叶过多，20名受试者的%5+叶显示核分叶过多。他们钴胺素缺乏的情况并不比没有核分叶过多的受试者更常见。此外，在34名dUST结果诊断为钴胺素缺乏的受试者中，只有1名有中性粒细胞核分叶过多。169名受试者的中性粒细胞分叶的两个指标均与同型半胱氨酸水平显著相关。它们还与钴胺素水平呈弱负相关，但与MMA、叶酸或MCV值无关。与8名非缺乏对照相比，对35名轻度缺乏的受试者进行6个月的钴胺素治疗并没有显著改变中性粒细胞叶平均数，对%5+叶的改善也很有限。一个令人惊讶的偶然发现是，黑人在这两个标准下的中性粒细胞分叶均显著高于白人和其他种族。这种差异与钴胺素或叶酸状态无关。我们的结果表明，dUST异常先于缺乏的所有形态学变化，包括核分叶过多。尽管在轻度钴胺素缺乏时，随着一些血清值（尤其是同型半胱氨酸）开始恶化，中性粒细胞分叶有非常轻微增加的趋势，但代谢变化先于明显的核分叶过多。中性粒细胞核分叶在缺乏的代谢证据方面不够敏感，不能作为诊断轻度钴胺素缺乏的临床工具。
