* Firstly, "poisoning" and "poisons" are the broadest of terms. Many poison determinations utilize a very wide variety of methodologies that I could not discuss without some specificity.

Secondly, bed side testing, also called "point of care" testing, for toxicology related situations is an untapped area. Mostly because the current types of testing require involved sample prepping and the use of sizable instruments to analyze the products.

In cases of poisoning what are the test/ bedside test done to diagnose it?

* There are very few tests that can be used at bedside. There are numerous drugs of abuse testing that can be run on a card and a little urine, other poisons, not so much.

Are they routinely done in your hospital set-up?

* point of care testing-- no. However our laboratory screens for many drugs using a mass spectrometer. As to other poisons, there is literature that descrbes many techniques for quick testing of other poisons like heavy metals, cyanide etc..

Are there any quick test to diagnose/ confirm a known poison?

* By "quick tests" you may be referring to what we call "spot tests". Spot test can be very general or very specific for a particular compound or classes of compounds. Again literature can be helpful here. A word of caution, spot tests should not be used soley for the determination of a poison or compound. It is strongly suggested that confirmatory (using another methodology) testing be performed before acting on a presumptive spot test.

Are there any test like urine pregnancy test kits to diagnose poisoning cases?

* Yes mostly pertaining to drug use.

Is it really helpful to diagnose poisoning cases by such test?

* In cases involving drugs of abuse, yes. Again, confirmatory testing should be followed up.

Can this be of some importance to medical or medicolegal purpose?

* Testing of newborn urine to determine drug abuse by pregnant mothers is an example of a medicolegal purpose.

Most diagnoses of toxicity are made based on patient history and the clinical presentation (i.e., the signs, symptoms, and results of general lab tests). Since the mainstay of treatment in chemical poisoning is supportive care, these basic findings are often sufficient to begin therapeutic intervention. On the other hand, if the physician suspects a toxicant or class of toxicant for which a specific antidote exists, he or she may desire additional confirmative information. Furthermore, for patients in acute distress, stat (urgent) diagnostic testing is necessary. Because of this need, several qualitative and semiquantitative tests have been developed to rapidly identify selected toxicants. These tests are used with the understanding that there is a balance between the need for quick decision making and the need for accuracy. The National Academy of Clinical Biochemistry has prepared a set of guidelines for two tiers of laboratory tests that should be available for patients in emergency departments. The first tier consists of “stat” (i.e., with an ideal reporting turnaround time of 1 h or less) tests for selected toxicants that are commonly encountered and for which a semiquantitative test is available (see Table 21.1). Usually, these tests are based on immunoassay technology (described in Section 21.4). The second tier of tests consists of comprehensive or broad-spectrum analyses for toxicants that may not have been identified in the first tier, or are unavailable on a stat basis, or for which quantitative results are needed for long-term patient management. These tests entail more quantitative analytical tools such as GC/mass spectrometry (MS) and high-performance liquid chromatography (HPLC). Smaller hospitals that do not have adequate resources to perform these tests usually send samples to a local or regional reference laboratory or toxicology laboratory for analysis. For purposes of monitoring therapeutic effectiveness, it is sometimes more practical to rely on other biomarkers of toxic effect such as acetylcholinesterase activity or coagulation, rather than on the concentration of the toxicant itself.

TABLE 21.1 Recommended “Stat” Toxicology Assaysa

Serum (Quantitative or Semiquantitative)

Acetaminophen Lithium Salicylates Theophylline Valproic acid Carbamazepine Digoxin Phenobarbital Iron

Ethanol Methanol Ethylene glycol Methemoglobin,

carboxyhemoglobinb

Urine (Qualitative)

Cocaine

Opiates

Barbiturates Amphetamines Propoxyphene (Darvon) PCP

Tricyclic antidepressants

a. Adapted from Wu et al. National Academy of Clinical Biochemistry Laboratory Medicine Practice guidelines: Recommendations for the use of laboratory tests to support poisoned patients who present to the emergency department. Clin. Chem. 49 (3): 357–379, 2003.

b. Not specific for any of the multiple toxicants that produce methemo- globinemia or carboxyhemoglobinemia. Detected by co-oximetry, which measures oxygenated hemoglobin as a percentage of total hemoglobin.

Few toxins can be detached like silver nitrate test which can be done aluminum phosphide .

Procedure: A piece of filter paper impregnated with 0.1 N of silver nitrate is put over the mouth in the form of mask and patient is asked to breath. Blackening of paper shows presence of phosphine.

Similarly for Iron poisoning can be diagnosed by qualitative desferroxamine test.

Procedure: add 30% of hydrogen peroxide to gastric fluid and on addition of 0.5ml desferroxamine color change from orange to red indicates iron poisoning.

Dr Murthy sir very nice examples.

But my question is do you doing that test in your hospital. If yes, than how useful is it in diagnosing and treatment purpose.

Are you mentioning this test result in the case papers of hospital record?.

whether this can be of any use for medicolegal purpose?

Can we give cause of death by this poisoning on the basis of test result?

These test will help physician treating as these can be done bed side. But its admissibility in the court of law depends on how the facts are presented and defended. It is always wise to confirmation by forensic science lab as court require quality and quantity.

Dr murty sir whether the Forensic science laboratory in our is able to detect every poison, even the routine common drug or vegetable poison. So how it is wise to depend on them.

also if the diagnosis given by hospital bedside test regarding poison, if it differs from Fsl reports than which will be more authentic.

Any time you need to ask this question concerning a patient; you must have some suspicion that there has been fowl play with the patients' health. I would run a full toxicology screening on the patient: Blood, Urine and Tissue Samples.  Be certain to rule out Ethylene Glycol in the Renal System; as this is one of the more frequently undetected poisons in humans that can kill within 12-24 hours and go undetected unless specifically tested for in Autopsy.

Ethylene Glycol is Anitreeze for automobiles and readily available for sale over the counter. It can be easily added to foods such as Gelatin or to sweet drinks, as it has a sweet flavor; which is why Felines often lick antifreeze that spills over in cars and become fatally-ill with sudden kidney failure.