Laflamme D P, Mahaffey E A, Allen S W, Twedt D C, Prasse K W, Huber T L
Department of Physiology, University of Georgia, Athens 30602.
J Vet Intern Med. 1994 May-Jun;8(3):212-6. doi: 10.1111/j.1939-1676.1994.tb03218.x.
Microcytosis is common in dogs with congenital portosystemic shunts (PSS) and acquired liver disease. The objective of this study was to determine if microcytosis could be induced in normal dogs by surgical creation of PSS, and to characterize the changes in hematology and iron status. Hematocrit, mean cell volume, mean cell hemoglobin, and mean cell hemoglobin concentration decreased linearly from 45.5%, 69.1 fL, 22.8 g/dL and 33.1% to 39.5%, 55.9 fL, 17.8 g/dL and 31.9%, respectively, 18 weeks after creation of PSS. The erythrocyte count did not change, but red cell distribution widths indicated a shift to a heterogenous population with decreased volume. Mean cell volume and mean cell hemoglobin decreased rapidly after induction of PSS and were significantly (P < .05) different from presurgery values within 2 weeks. Serum iron and copper concentrations and total iron binding capacity were decreased in dogs with PSS. Liver iron concentration doubled after creation of PSS, with the majority of stainable iron located in Kupffer cells. The changes in erythrocyte indices and measures of iron status in dogs with surgically induced PSS were similar to those in dogs with congenital PSS. Microcystosis developed rapidly in dogs after induction of PSS. These results indicate that iron deficiency was not the cause of microcytosis in these dogs.
小红细胞症在患有先天性门体分流（PSS）和后天性肝病的犬类中很常见。本研究的目的是确定通过手术创建PSS是否能在正常犬类中诱发小红细胞症，并对血液学和铁状态的变化进行特征描述。在创建PSS后18周，血细胞比容、平均红细胞体积、平均红细胞血红蛋白含量和平均红细胞血红蛋白浓度分别从45.5%、69.1 fL、22.8 g/dL和33.1%线性下降至39.5%、55.9 fL、17.8 g/dL和31.9%。红细胞计数没有变化，但红细胞分布宽度表明向体积减小的异质群体转变。诱导PSS后，平均红细胞体积和平均红细胞血红蛋白迅速下降，在2周内与术前值有显著差异（P < 0.05）。患有PSS的犬类血清铁、铜浓度和总铁结合能力降低。创建PSS后肝脏铁浓度翻倍，大部分可染色铁位于库普弗细胞中。手术诱导PSS的犬类红细胞指数和铁状态指标的变化与先天性PSS犬类相似。诱导PSS后犬类迅速出现小红细胞症。这些结果表明缺铁不是这些犬类小红细胞症的原因。
