Diagnostic dilemma: A woman got unusual bruising from a massage gun. It turned out she had scurvy.

The patient: A 37-year-old woman in Philadelphia

The symptoms: The patient went to the emergency department after four days of pain, swelling and bruising on the upper part of her left knee. She reported that these symptoms appeared after she'd used a massage gun on her leg.

What happened next: Doctors took the woman's medical history, noting that she had been on blood thinners for about six years due to previously having a blood clot in her lung and a stroke caused by a small birth defect in her heart that had allowed a clot to reach her brain. She also reported heavy menstrual bleeding.

Doctors saw bruising on her thigh, knee and calf, with swelling but no joint damage or blood clots on scans. They advised the patient to stop using the massage gun, continue her medication regimen and follow up later.

A few weeks later, she returned with shortness of breath and lightheadedness, and she still had bruising on her leg. An MRI of the leg showed tissue swelling and a small muscle bruise, typically caused by blunt trauma to the tissue. Blood work revealed that her red blood cells and hemoglobin — the part of blood that carries oxygen — had dropped to dangerously low levels.

Suspecting that the patient may have anemia due to an iron deficiency, the medical team also checked her iron levels and found they were low. To search for a potential source of blood loss, doctors ran stool tests and did stomach and colon scopes, all of which were normal.

The patient was discharged with a prescription for daily iron tablets and weekly intravenous iron, but these failed to keep her hemoglobin levels up. She then received several blood transfusions, with each transfusion briefly lifting her numbers, only for them to fall again within a week. Concerns about her low hemoglobin levels prompted doctors to pause her blood thinners and to have an intrauterine device placed, to stop any menstrual bleeding.

About six weeks into this decline, she returned to the emergency department with chest pain, night sweats, weight loss and worsening breathlessness. Her lungs sounded clear, but scans showed the right side of her heart was enlarged and weak, and pressures in her lungs were very high, a condition called pulmonary hypertension. Her oxygen levels worsened overnight, so the doctors transferred her to intensive care. At that point, doctors noticed that she had tiny red spots around the hair follicles on her legs and that the hairs twisted into corkscrews; she also had swollen, purplish gums.

The diagnosis: The red spots, corkscrew hairs and swollen gums were classic signs of vitamin C deficiency, and tests confirmed her vitamin C level was undetectable. Upon further questioning, she then reported that citrus foods gave her hives, so she had avoided them for years. (Additional fruits and vegetables can also be good sources of vitamin C; the woman's doctors didn't note whether she consumed any of those other foods.)

Without vitamin C, the body cannot build strong collagen, the scaffolding that supports blood vessels and tissues. Fragile vessels leak, bruises linger, wounds heal poorly, and in rare cases, the strain can affect the function of the heart and lungs.

The treatment: Doctors started the patient on high-dose oral vitamin C supplements and the turnaround was dramatic. Within 48 hours, she was stable enough to leave intensive care. She was then discharged with a prescription for vitamin C supplements, an iron-containing multivitamin, and medications for her pulmonary hypertension.

Over the next weeks, her blood counts rose without more transfusions, her bruises and gum swelling faded, and her breathing improved. Her blood thinner was restarted safely. Within six months of discharge, she no longer needed medicines for pulmonary hypertension, her heart function and scans returned to normal, and she was back to exercising as she had before the bruising event.

What makes the case unique: Scurvy is usually remembered as a historical sailor's disease, but this form of malnutrition can still affect people in the modern day.

Most cases of scurvy cause fatigue, easy bruising or mild anemia, but this patient developed transfusion-dependent anemia, meaning she required regular blood transfusions to keep her blood counts up. Her condition was so severe it did not respond to iron therapy — a rare occurrence described only occasionally in medical literature.

She also developed high lung pressure with strain in the right side of the heart, an uncommon complication of scurvy that typically improves only when vitamin C is replaced, not with standard drugs for the treatment of pulmonary hypertension.

"The current case serves as a reminder that scurvy continues to occur in the United States and highlights its potential severity and clinical features," doctors wrote in a report of the case. "It also underscores the importance of a dietary-history review, especially when a diagnosis is elusive."

For more intriguing medical cases, check out our Diagnostic Dilemma archives.