After a 19-year-old man developed "a strange rash on his arms and legs" and noticed blood in his urine, he learned that a platelet disorder was preventing his blood from clotting—and tests revealed a surprising trigger, Lisa Sanders writes for the New York Times Magazine.

Symptoms

In the middle of the night, the 19-year-old man noticed that something was off when he went to the bathroom.

When he looked down, he saw that the water in the bowl was a deep red, resembling the color of cranberry juice, Sanders writes. Although the man's girlfriend encouraged him to go to the ED right away, he decided to wait until the following morning to speak with his mother, who experienced similar symptoms before being diagnosed with a platelet disorder several years earlier.

After the man spoke with his mother, he agreed to visit the ED at Yale New Haven Hospital. While he did not feel sick, he was concerned.

In the ED, he explained that he had developed "a strange rash on his arms and legs" before noticing blood in his urine, Sanders writes.

According to Sanders, the rash consisted of "[t]iny red dots" that "didn't hurt or itch." The specks, which the man soon learned were called petechiae, are typically indicative of an abnormally low level of platelets. The man explained that his mother had a platelet disorder and told the physician assistant that he suspected he might have the same condition.

Blood tests quickly confirmed the man's suspicion—he had a platelet count of two. "Normal is 150 to just over 400," Sanders wirtes. "With so few platelets, the young man was in danger of bleeding to death if he were injured."

Then, a hematologist at the hospital diagnosed the man with a disorder known as immune thrombocytopenia (ITP)—the same condition his mother was diagnosed with years before.

"This is a somewhat mysterious disorder in which a patient's own immune system destroys completely normal platelets," Sanders writes. "The cause is often not found. But just over a third of the time, the disorder can be linked to an infection or other disease process that somehow triggers the body's antibodies to attack these essential clotting components."

While he was still in the ED, the man was given intravenous immunoglobulin to help increase his platelet counts. He was then admitted to the hospital.

'I'm betting on cat-scratch fever'

When the man met Emily Fishman, the intern assigned to care for him in the hospital, he explained that his symptoms began almost a month before he developed a rash on his arms and legs. 

According to the man, he started experiencing severe cold symptoms, which went away within a few days. However, as he started to recover, he noticed a large lump on the side of his neck.

"At first it was just a little tender," Sanders writes. "But soon it became big and tender. It was as if he had a marshmallow buried under his skin. It got so big it scared him."

At the ED, a CT scan showed what appeared to be an inflamed lymph node. However, when doctors tested him for mononucleosis, it came back negative, so he was sent home with instructions to follow up with an ear, nose, and throat doctor.

Then, as the mass on his neck started to shrink, he started to feel worse. "He was feverish, sweaty and tired. He had no appetite. He considered going back to the E.D. but didn't feel quite that sick," Sanders writes. "And after a few days, he felt fine again. That's when he saw the rash."

As Fishman examined the man, she noticed dots that resembled small scabs on his arms. "What's this?" she asked. The patient explained that the marks were from his four cats.

Following her evaluation, Fishman consulted with the senior resident she was working with, Neeharika Namineni. After tests ruled out thyroid issues and tick-borne diseases, the doctors considered other possibilities, including early-stage HIV, cancer, cat-scratch fever, or toxoplasmosis.

The following morning, Fishman and Namineni met with the patient's attending physician, Lloyd Friedman. As Fishman explained their theories, Friedman's eyes "lit up" when she mentioned the cat scratches, Sanders writes.

"I'm betting on cat-scratch fever," he said enthusiastically after Fishman finished speaking. Friedman pondered aloud if cat-scratch fever could trigger ITP. A quick internet search unveiled a single case report, making the connection "uncommon but still possible," Sanders writes. Still, with "the scratches, the fever, the hugely swollen lymph node," Friedman maintained his theory.

Was his condition 'just a coincidence?'

In the following days, the patient received several doses of intravenous immunoglobulin, bringing his platelet count from two to 60.

While his platelet count was still below normal the man "was safe (and eager) to leave the hospital," Sanders writes. After the man went home, Fishman monitored his lab results, which soon ruled out toxoplasmosis or acute HIV.

"Finally, they got their answer: He had cat-scratch fever, an infection caused by a bacterium called Bartonella henselae," Sanders writes. "By then the patient's symptoms were long gone. Even the swollen lymph node was barely visible."

In the following weeks, a test revealed that the man's platelets had returned to normal. Still, he wonders if there is a genetic connection between his experience and his mother's.

"Was it just a coincidence that he got this, too?" Sanders writes. "It's a question for his mother's hematologist. But he thinks it's kind of cool that it's all in the family." (Sanders, New York Times Magazine, 12/29)