CASE REPORT Poisoning of a dog with the explosive pentaerythrityl tetranitrate A three-year-old male Labrador retriever was presented at the Clinic of Internal Medicine, University of Zagreb, Croatia. The owner reported that the dog was ataxic, and this was evident by its markedly unsteady, swaying gait. The dog also had difficulty rising and fell several times while trying to stand. It had come into contact with the explosive, pentaerythrityl tetranitrate, while training to detect explosives. The following clinical symptoms were observed: bradycardia, depression, mild disorientation and a broad-based stance. The dog had conscious proprioceptive deficits in the hindlimbs, but cranial nerve function was normal except for miosis. Ion scan analysis of the dog’s serum after evaporation of the current phase by mass spectroscopy revealed the presence of fragments that are characteristic of pentaerythrityl tetranitrate. The aim of the present case report was to identify pentaerythrityl tetranitrate poisoning and describe the clinical signs of pentaerythrityl tetranitrate poisoning in dogs. To the authors’ knowledge, there are no published scientific articles on pentaerythrityl tetranitrate poisoning in dogs. D. POTOC ˇ NJAK, R. BARIC ´ -RAFAJ, N. LEMO, V. MATIJATKO, I. KIS ˇ , V. MRLJAK AND I. HARAPIN Journal of Small Animal Practice (2008) 49, 314–318 DOI: 10.1111/j.1748-5827.2008.00549.x INTRODUCTION Pentaerythrityl tetranitrate (PETN) is a nitroglycerin compound. PETN (also known as penthrite) is one of the strongest known high explosives. PETN does not occur naturally, so the production and use of this type of product can lead to con- tamination of the environment. PETN is subject to biodegradation in untreated urine and faeces. There have also been some reports of its degradation by bacteria (Binks and others 1996). It is more sensi- tive to shock and friction than TNT or tet- ryl, and it is never used alone as a booster. It is used primarily in booster and bursting charges of small calibre ammunition, in upper charges of detonators in some land mines and shells and as the explosive core of detonation cord (Stettbacher 1919). PETN is known to cause long-term antioxidant and anti-atherogenic effects by as yet unidentified mechanisms (Oberle and others 2002). Nitroglycerin has been used (in sublingual form) for more than 100 years to alleviate the symptoms of angina pectoris. It has also become an important therapeutic agent for chronic congestive heart failure and for heart fail- ure associated with acute myocardial infarction. In addition, it has been found to reduce acute myocardial ischaemia, enhance electrical stability of ischaemic myocardium and improve localised ven- tricular asynergy (POISINDEX 1998). Exposure to industrial nitroglycerin is involved in jobs that require working with dynamite, cordite and blasting gelatin (Rabinowitch 1944). The most common adverse side effects of nitroglycerin seen in human medicine are usually related to the cardiovascular system. Nitrate administration is some- times associated with mild hypotension, but serious side effects are uncommon. The efficacy of nitrates is attributed to their vasodilator effects, especially their peripheral venodilating properties. A de- crease in venous return and, to a certain extent, in arteriolar resistance usually causes hypotension of varying degrees. This hypotension leads to baroreceptor- mediated reflex stimulation of the vaso- motor centre. In turn, vascular tone and heart rate both increase, helping to regu- late blood pressure (Khan and Carleton 1981). Acute nitroglycerin poisoning in human beings is characterised by nausea, vomiting, abdominal cramps, diarrhoea, headache, mental confusion, delirium, bradypnea, bradycardia, paralysis, convul- sions, methaemoglobinaemia, cyanosis, circulatory collapse and death (Merck Index 1989). Therefore, nitroglycerin must be administered with caution. Poisoning in human beings after oral ingestion is uncommon, unless large doses have been ingested. There are insufficient data in the literature to enable an accurate assessment of an acute sublingual or oral toxic dose of nitroglycerin. Determining the severity of intoxication after oral inges- tion should be based on clinical findings (POISINDEX 1998). Although nitroglyc- erin has been used to treat bronchial asthma in dogs (Merck Index 1989, The Clinic of Internal Medicine, The Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, Zagreb 10000, Croatia 314 Journal of Small Animal Practice Á Vol 49 Á June 2008 Á Ó 2008 British Small Animal Veterinary Association