Badu Isaac K, Girela Eloy, Beltrán Cristina M, Ruz-Caracuel Ignacio, Jimena Ignacio
Section of Legal and Forensic Medicine.
Section of Legal and Forensic Medicine
Med Sci Law. 2015 Jul;55(3):228-35. doi: 10.1177/0025802414538791. Epub 2014 Jun 24.
A diagnosis of drowning is a challenge in legal medicine, as there is generally a lack of pathognomonic findings indicative of drowning. Diatom analysis has been considered very supportive for a diagnosis of drowning, although the test is still controversial for some investigators. We assessed diatoms association with drowning in the peripheral tissues of drowned rats and the effects of the drowning medium on the diatom yield. A modified acid digestion method was optimised for diatom recovery in water and rat tissues. Eighteen adult Wistar rats were employed for the study, subdivided into six groups of three rats. Groups 1, 3 and 5 were drowned in seawater, lake water, or river water respectively, while groups 2, 4 and 6 were controls (immersed after death in seawater, lake water or river water respectively). Water samples were taken from the sea, lake and river in Málaga and Córdoba (Spain) for the purposes of diatomological mapping and drowning of the rats. Diatoms were successfully recovered from all water samples and matched with tissues of the drowned rats. There were significant differences in diatom numbers between control and test samples for all the tissues studied, as well as within test samples. Histological investigations conducted on lung samples obtained from drowned rats provided complementary and valuable information. This study demonstrates the feasibility of the diatom test as a reliable method for the diagnosis of drowning, especially if adequate precautions are taken to avoid contamination, and if interpretation of the analysis is performed in light of other complementary investigations.
溺水的诊断在法医学中是一项挑战，因为通常缺乏指示溺水的特征性发现。硅藻分析一直被认为对溺水诊断有很大帮助，尽管该检测对一些研究人员来说仍存在争议。我们评估了溺水大鼠外周组织中硅藻与溺水的关联以及溺水介质对硅藻产量的影响。优化了一种改良的酸消化方法以用于从水和大鼠组织中回收硅藻。18只成年Wistar大鼠用于该研究，分为6组，每组3只大鼠。第1、3和5组分别在海水、湖水或河水中溺水，而第2、4和6组为对照组（分别在死后浸入海水、湖水或河水中）。从西班牙马拉加和科尔多瓦的海、湖和河中采集水样用于硅藻图谱绘制和大鼠溺水实验。所有水样中均成功回收了硅藻，并与溺水大鼠的组织进行了匹配。在所研究的所有组织中，对照样本和测试样本之间以及测试样本内部的硅藻数量均存在显著差异。对溺水大鼠的肺样本进行的组织学研究提供了补充性的有价值信息。本研究证明了硅藻检测作为一种可靠的溺水诊断方法的可行性，特别是如果采取了足够的预防措施以避免污染，并且如果根据其他补充性研究对分析结果进行解释的话。
