Doctors who admitted a 17-month-old girl to the hospital in Arizona thought her tremors and other symptoms were due to a scorpion sting. Only later did they realize the real cause of her condition was that she'd consumed methamphetamines, according to a new report of her case.

The young girl in the case recovered and was discharged from the hospital a week later.

People who have been stung by scorpions of the species Centruroides sculpturatus, which is common in Arizona, often have some of the same symptoms as the girl, said Dr. Farshad Shirazi of University of Arizona College of Medicine, who was one of the doctors who treated the child and a co-author of the case report. 

The case highlights the similarity between the symptoms of a scorpion bite and those of drugs like methamphetamine, the researchers wrote in their case report.

"These [symptoms] include some movement disorders, and movement of upper and lower extremities, and some foaming at the mouth," Shirazi told Live Science. [6 Strange Meth Facts]

When the girl arrived at the emergency department of a hospital in Tucson, Arizona, she was agitated, twitching throughout her entire body, sweating profusely and salivating excessively. Her doctors had previously seen such symptoms in patients bitten by the Arizona bark scorpion, which is endemic to this region of the United States.

The girl's mother said she had indeed seen scorpions many times at their home, so the doctors suspected that the girl had been bitten, and treated her by administering three vials of anti-venom.

This treatment put a stop to the girl's uncontrollable eye movements and salivation, but she continued to experience the tremors. The patient also had a fever, and her heart rate was too high. Meanwhile, the doctors were not able to find any physical indication of a scorpion sting by examining the girl's skin.

The patient's mother eventually revealed that the girl's grandmother temporarily left the tot alone with an aunt who used methamphetamines. The doctors then tested the child's urine and found she had indeed ingested the drug. This was confirmed several weeks later by the results of a blood test. However, it was not clear exactly how the ingestion occurred, the report said.

After receiving treatment for methamphetamine intoxication, the girl recovered.

There have been other reports of children in Arizona ingesting methamphetamines and developing symptoms mistaken for those of scorpion envenomation. One likely reason for this phenomenon is that getting bitten by this type of scorpion is not uncommon in the southwestern United States, the researchers said.

At the same time, "there is a predominance of methamphetamines in the same geographic area of the U.S., as the endemic locale of the C. sculpturatus," the doctors wrote in the report. In 2012, a little less than 11,000 kilograms (24,250 lbs.) of methamphetamine was seized along the southwestern U.S. border with Mexico, which was the highest amount ever recorded, the authors wrote.

"Arrestee data show stable rates of testing positive for methamphetamines in the western and southwestern United States versus the rest of the country, which reveals [their] geographic predominance and areas with higher rates of use," according to the report.

The researchers are also currently investigating why some of the girl's symptoms improved following the administration of the anti-venom, even though the real cause of her symptoms was methamphetamine intoxication. One possibility is that the protein present in the anti-venom bonded with the methamphetamine and led to the improvement, but the exact mechanism is not completely clear, they said.

The report was published in the January issue of the journal Case Reports in Emergency Medicine.

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