By: By Catherine Winters, Contributing writer
Published: 07/24/2013 08:19 AM EDT on LiveScience
A woman who devoured a 1-pound box of baking soda a day — before and during her pregnancy — developed serious muscle and heart conditions, according to a report of her case.
But it took doctors a week from the time she was hospitalized to pinpoint the cause of her life-threatening illnesses: the mysterious condition known as pica.
The condition involves cravings for nonfood items such as cornstarch, clay, baking powder, dirt or ice, and is common during pregnancy.
The 35-year-old mother-to-be, who showed up at the hospital complaining of weakness and dizziness during her 37th week of pregnancy, was initially diagnosed with an irregular heartbeat and muscle weakness in her legs. She also had low levels of potassium, an electrolyte vital for the proper functioning of nerve and muscle cells, especially the heart muscle.
"The low potassium levels explained why she was weak" and her irregular heartbeat, said Dr. Thomas Myles, co-author of the report and a professor of obstetrics, gynecology and women's health at St. Louis University in Missouri. [9 Conditions That Pregnancy May Bring]
But the next question that doctors needed to answer was why her potassium levels were low.
"I had seen a patient who was weak from overdoing caffeine, so I thought about diet," Myles said. He said he is also familiar with pica and its symptoms, but the patient didn’t admit to any unusual dietary practices.
Doctors admitted the woman to the hospital, and when she developed a rapid heart rate, they transferred her to the intensive care unit, treating her with fluids and electrolytes.
Then lab tests found high blood levels of creatine kinase, an enzyme that signals a condition called rhabdomyolysis, a breakdown of muscle fiber that can harm the kidneys.
When an echocardiogram showed that the left ventricle of the woman's heart was dilated, doctors suspected the woman also had a condition called peripartum cardiomyopathy. This condition occurs when the heart muscle weakens and is unable to pump blood efficiently. It affects one in every 1,300 to 5,000 births, and is usually diagnosed during the last month of pregnancy, or within five months of delivery, according to the National Institutes of Health.
After doctors treated the woman with heart medication and a blood transfusion, they induced labor. On her fifth day in the hospital, she delivered a healthy 5-pound, 4-ounce baby boy.
Further treatment improved her creatine kinase levels, but her potassium levels stayed stubbornly low.
During her hospital stay, the doctors and nursing staff kept questioning the woman about her dietary and other habits. Finally, two days after giving birth, she admitted she had been downing baking soda daily for several years, as a remedy for hiccups. She had even consumed some while in the hospital.
"I suspect she felt a little guilty that her symptoms were self-induced," Myles said.
She was told to stop eating the baking soda, and was closely watched to make sure she complied. Within a day, her potassium levels returned to normal and she was discharged.
At that point, the woman began to see a cardiologist, and three months later, an echocardiogram showed she still had mild cardiomyopathy, Myles said.
However, the muscle weakness in her legs had resolved. "As soon as you get away from the offending trigger and stay hydrated, muscle becomes stable and rebuilds," Myles said.
The baking soda, which is mainly sodium bicarbonate, triggered a cascade of metabolic abnormalities that led to her condition. Once the woman stopped her baking soda habit, "it made it a lot easier to treat her," Myles said.
The case report is published in the August issue of the journal Obstetrics & Gynecology.