Diagnostic dilemma: A woman kept tasting bleach — and doctors found a hidden cause in her blood

The patient: A 36-year-old woman in Michigan

The symptoms: The woman went to the emergency department after experiencing severe shortness of breath, abdominal pain and fatigue for about a day. She had a complex medical history, including obesity, sleep apnea and vitamin deficiencies, as well as psychiatric conditions, such as anxiety, depression and post-traumatic stress disorder (PTSD).

Twice before, she had been hospitalized for psychiatric episodes. But recently, she'd been receiving treatments — a daily antidepressant and a monthly long-acting antipsychotic injection — that appeared to be keeping further episodes at bay.

What happened next: The patient had been given oxygen en route to the hospital. Once there, doctors stabilized her with multiple blood transfusions after lab tests pointed to anemia, in which the body has too few healthy red blood cells to carry oxygen through the body.

Her blood had low levels of hemoglobin and platelets, the parts of blood that carry oxygen and help form blood clots, respectively. Her heart also showed signs of enlargement on X-ray, indicating it was compensating for the blood's inadequate oxygen-carrying capacity.

Doctors tested the levels of iron and folate in the patient's blood, as these nutrients are essential for the formation of red blood cells. The results of these tests were normal, but her level of vitamin B12 — a micronutrient critical to red blood cell formation — was dangerously low. Later tests revealed that she carried antibodies that interfere with B12 absorption.

The diagnosis: These findings were consistent with pernicious anemia, a condition in which the body's own immune system attacks the stomach cells needed to absorb vitamin B12. Without enough B12, the body can't produce healthy red blood cells, and prolonged deficiency can cause cognitive and behavioral changes, including mood disturbances and, in some reports, psychosis.

Given the patient's psychiatric history, the emergency room doctors consulted a psychiatric team after she was stabilized. At that point, she reported that she had been tasting powdered household bleach two or three times a day for over a month, as she was drawn to its sharp smell and gritty texture. She said she would lick her finger, dip its tip into the powder, put it in her mouth, swish it, and then spit and rinse, and she denied ever swallowing it.

Her family was worried, she said, but she was "neither concerned nor bothered by her behavior," her doctors noted in a report.

The behavior pointed to pica, a disorder in which people compulsively eat or taste nonfood substances, such as dirt, ice or starch. In this case, the compulsion seemed to be tied to the patient's anemia, in that her B12 deficiency was at the root of both the blood disorder and the behavioral changes.

The treatment: The patient's immediate care focused on stabilizing her vital signs with intensive monitoring in the intensive care unit and transfusions to restore her blood levels and relieve the burden on her heart. Once stable and deemed fit for discharge, she was prescribed vitamin B12 supplements and medication to reduce stomach acid. She also agreed to undergo an endoscopy at an outpatient clinic to check for gastritis, or inflammation of the stomach lining.

Pernicious anemia "necessitates lifelong vitamin B12 supplementation to reverse the deficiency and alleviate corresponding psychiatric symptoms," the doctors noted in the report. However, after leaving the hospital, the patient never returned for follow-up, so the doctors don't know whether she continued her treatments or if her symptoms resolved.

What makes the case unique: In other cases, pica has often — though not always — been tied to vitamin and nutrient deficiencies, particularly a lack of iron or zinc. In this case, the behavior stemmed from a severe vitamin B12 deficiency. The clinicians called it "the first of its kind, notable for the underlying anemia from B12 deficiency."

The report also noted that the patient's presentation draws attention to a rare and recently identified variant of pica called desiderosmia, in which a person's cravings initially seem to be fueled more by smell than by taste or the act of ingestion.

The case stands as a reminder of how psychiatry and medicine need to be evaluated alongside each other to provide patients holistic care. With her psychiatric history, the patient's bleach craving might easily have been dismissed as having only psychological causes, the authors argued.

The case highlights how such behavioral changes should prompt careful medical evaluation alongside psychiatric consultation, since they may be the first clue to a hidden, life-threatening disease, the doctors concluded.