北美学到的一些取得正确诊断的有益思路 Helpful tips to achieve accurate diagnoses learnt from North America 黄彦云 兽医 ; 硕士 ; 博士 ; 北美兽医病理协会认证病理师 加拿大平原诊断服务副诊断总裁及病理师 萨斯卡切温大学客席教授 Yanyun Huang BAgr (Vet Med), MAgr (Vet Path), MSc, PhD, DACVP Associate Director of Diagnostics and Anatomic Pathologist Prairie Diagnostic Services Inc. Adjunct Professor Department of Veterinary Pathology University of Saskatchewan
#1 注意用多种方法验证一个诊断 Use more than one method to confirm a diagnosis
哺乳仔猪, 急性死亡 有一些有腹泻 死亡率约 1% Suckling pigs, acutely died. Some degree of diarrhea. Mortality ~1%. 你会怎样做? What will you do? PCR: PED -, TGE -, DCV -, Rotavirus A + 这是轮状病毒引起的腹泻死亡吗?Is this rotavirus diarrhea and death?
肠毒性大肠杆菌 Enterotoxigenic E. coli (ETEC) http://what-when-how.com/acp-medicine/infections-due-to-escherichiacoli-and-other-enteric-gram-negative-bacilli-part-1/
#1 注意用多种方法验证一个诊断 Use more than one method to confirm a diagnosis 以上面的病例为例, 很多北美临床医生会要求实验室做 In this case, many vets in North America will order: 病理组织学 Histopathology 肠道细菌培养 ( 配以 F4 和 F18 凝集试验 ) Culture of the guts (with F4 and F18 agglutination tests) ( 如果没有凝集试验,PCR 也可以 if agglutination test not available, PCR can work) PCR: PED, TGE, rotavirus 加上临床观察, 大体病变观察, 一共是 7 种方法 With clinical and gross observation, 7 methods are involved to achieve the diagnosis of ETEC
#1 注意用多种方法验证一个诊断 Use more than one method to confirm a diagnosis 使用多种方法是验证一个诊断是谦卑的表现 To use several methods to establish a diagnosis is an act out of humility 使用多种方法是验证一个诊断是充分考虑到疾病的各种可能 To use several methods to establish a diagnosis demonstrate the understanding of different possibilities 使用多种方法是验证一个诊断不是大包围, 需要有过硬的临床知识帮助选择需要的方法 To use several methods to establish a diagnosis is not fishing, but needs good clinical skills to help to chose necessary methods
#2 病理学诊断是与其他实验室诊断配合的有力诊断工具 Pathology is a powerful tool to supplement other laboratory tests
断奶前仔猪腹泻,~20% 发病率 死亡不多 Pre-weaned piglets diarrhea, ~20% morbidity, but mortality is not high. 粪便黄色或白色, 水状至糊状 yellow to white, watery to pasty diarrhea
检测结果 test results: PED 你的诊断是什么? What is your diagnosis? 还是你觉得是否有足够的资料去诊断? Or can you have a diagnosis from these information? 假设你还做了轮状病毒,TGE,Delta 冠状病毒检测, 都是阴性 suppose you have also done PCR for rotaviruses, TGE, Delta coronavirus, and they are all negative?
回肠绒毛完全消失 Subtotal loss of villi 正常
断奶仔猪腹泻, 发病率最高达 80%, 死亡率 12% post weaning diarrhea, morbidity as high as 80%, mortality 12%
分离到沙门氏菌 Salmonella spp isolated
#2 病理学诊断是与其他实验室诊断配合的有力诊断工具 Pathology is a powerful tool 人是最强大的多重目标发现者 Human is the most powerful multiplex test 病理组织学可以观察到病原对组织的影响, 从而引导如何解释其他实验室检测的结果 Histopathology can reveal the effects of pathogens to tissues, to guide the interpretation of the other laboratory test results 病理组织学是中国动物疾病诊断系统所缺的一块重要拼图 Histopathology is an important missing piece of the Chinese animal diagnostic system
#3 检出 感染 发病 detection infection disease
断奶猪急性死亡, 偶发, 死亡前似乎有神经症状 post weaning pigs acute deaths, occasional, seemingly neurological signs before death PRRS PCR +, Ct 32
这是 PRRS 吗? Is this PRRS? PRRS PRRSV
#3 检出 感染 发病 detection infection disease 检出 感染 detection infection 需要有过关的检测技术 need to have confident test results 感染 发病 infection disease 在某种病原阳性的场, 有很多动物可以亚临床感染而不显著影响生长性能 In farms that are positive for a certain pathogen, there may be many sub-clinical infection which do not significantly affect performance 病理组织学可以观察到病原对组织的影响, 从而引导如何解释其他实验室检测的结果 Histopathology can reveal the effects of pathogens to tissues, to guide the interpretation of the other laboratory test results
#4 排除和确诊同等重要 To rule out is as important as to diagnose
你的鉴别诊断是什么? 措施是什么? What is your differentials? And what are your control strategies?
如果是猪瘟, 你怎样防控? 沙门氏菌? 圆环病毒? 大肠杆菌? What will you do if it is CSF? Salmonella? PCV2? ETEC?
如果都不是呢? What if all those differentials are ruled out?
#4 排除和确诊同等重要 To rule out is as important as to diagnose 在某种疾病阴性的场, 如果出现怀疑这种疾病的临床症状或病变, 马上排除 / 确定是否这种病原感染对这个场尤为重要 When you see clinical signs or lesions similar to what can be caused by a pathogen that is negative on this farm, to rule out/confirm this pathogen is very important
#1 注意用多种方法验证一个诊断 Use more than one method to confirm a diagnosis #2 病理学诊断是与其他实验室诊断配合的有力诊断工具 Pathology is a powerful tool to supplement other laboratory tests #3 感染 发病 infection disease #4 排除和确诊同等重要 To rule out is as important as to diagnose
致谢 Acknowledgements