“Hey, come here,” the 19-year-old man called out to his girlfriend. “This isn’t right.” Although it was nearly 2 a.m., the young woman jumped out of bed and hurried to the bathroom. Her partner had been sick on and off for the past few weeks, and they were both too worried to sleep. The water in the bowl was a deep red — the color of cranberry juice. It looked like pure blood when it came out, the young man told her. “You should go to the emergency room,” the girlfriend urged. Not yet, he said. He would rather get a little sleep and call his mother in the morning. She had something like this several years before.
The next morning, his mother agreed that he should go to the emergency room, and so the couple drove to the Yale New Haven Hospital. It was a Wednesday morning, and the place was quiet. He explained the bloody urine and was immediately brought back to be evaluated. He didn’t feel sick, but he was worried.
The previous night he noticed a strange rash on his arms and legs, he explained to the physician assistant in the E.R. Tiny red dots. They didn’t hurt or itch — just a bunch of flat dots, like freckles, only red. He immediately went to the internet. The specks, he learned, were called petechiae, from a 17th-century Italian word for freckles. Each dot marks the spot where a tiny bit of blood has been deposited under the skin. It usually suggests an abnormally low level of a blood cell type known as platelets. These tiny cell fragments are the first step in creating a clot after an injury. His mother had a platelet problem, he told the physician assistant, and now he thought maybe he did, too.
The young woman looked closely at the dots that covered his arms and legs; he was right — they were petechiae. There were other signs that his platelets were low: He had a blood blister on his tongue and a scattering of bloody spots on the inside of his cheek. And of course, he came in because of bloody urine.
In Danger of Bleeding to Death
The blood tests proved the patient right. His platelets were scarily low. He had a platelet count of 2 — that means he had two thousand platelets per microliter of blood. Normal is 150 to just over 400. With so few platelets, the young man was in danger of bleeding to death if he were injured. He was admitted to the hospital for treatment and observation.
A hematologist called to the emergency department diagnosed the young man with a disorder known as immune thrombocytopenia (ITP). This is a somewhat mysterious disorder in which a patient’s own immune system destroys completely normal platelets. 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.
In either case, the first step is to stop the destruction of the platelets. The patient was given intravenous immunoglobulin while he was still in the E.D. This treatment is made up of antibodies taken from thousands of blood donors. After 40 years of use, it’s still not clear exactly how it works, but these donated antibodies significantly increase platelet counts in most patients with ITP.
Dr. Emily Fishman, the intern assigned to care for the patient in the hospital, met the young man when he finally came to the floor. His story, he told her, actually started nearly a month before the rash began to dot his arms and legs. He caught what seemed like a bad cold. He tested himself for Covid-19: negative. And he started to feel better after just a couple of days. But even as he began to recover, he noticed a lump on the left side of his neck. At first it was just a little tender. 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. That was the first time he went to the E.D. A CT scan showed what looked like an inflamed lymph node. A test for mononucleosis was negative, so they sent him home after arranging for him to follow up with an ear, nose and throat doctor.
Over the next several days, the mass on his neck stopped hurting and then started to shrink. But while his neck felt better, the rest of him felt 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. And after a few days, he felt fine again. That’s when he saw the rash.
A Rash of Little Scabs
Fishman listened to the young man’s story and then examined him. The lump on his neck was obvious. She had seen it from the doorway. But it wasn’t tender and moved easily, the way lymph nodes are supposed to. The rash was also easily seen, but on his arms she noticed something different. “What’s this?” she asked, pointing to some dots that looked like tiny scabs. That’s from my cats, the patient replied. They had four at home. They liked to play and sometimes left marks.
After the exam, Fishman excused herself and went out to look for the senior resident she was working with, Dr. Neeharika Namineni. The resident had also seen the patient and reviewed his records. Fishman described what she found and went over the test results from the E.D. His thyroid was normal. He didn’t have antibodies for Lyme or the other tick-borne diseases frequently seen in the Northeast, anaplasmosis and babesiosis. He didn’t have any antibodies for H.I.V. Fishman paused. Still, he could have early H.I.V., at the stage before antibodies are present. It takes four to six weeks to develop a measurable number of antibodies to most infections. Moreover, an acute H.I.V. infection can start with a fever and a rash. So first she would like to send off a test to look for the H.I.V. itself, to make sure he wasn’t in the earliest stages of that infection. He also had these cat scratches. Could this be cat-scratch fever or toxoplasmosis? Each of those diseases can be transmitted from cats to humans through scratches; each can cause a febrile illness and enlarged lymph nodes. Finally, could this be evidence of a hidden cancer — maybe a testicular cancer — that had spread to his lymph nodes?
Namineni thought infection more likely, but certainly cancer was possible. Fishman added tests for these pathogens to their orders. If all the tests came back negative, they would look for a cancer.
The next morning they met with the attending for the patient, Dr. Lloyd Friedman. Again Fishman described the patient and her thoughts. Friedman’s eyes lit up when the young woman mentioned the cat scratches. “I’m betting on cat-scratch fever,” he announced enthusiastically once she finished her presentation. Friedman wondered aloud if that infection can cause ITP. A quick search of the internet turned up a single case report. So it was uncommon but still possible. Friedman doubled down. The scratches, the fever, the hugely swollen lymph node: This felt to him like cat-scratch fever.
The patient got several doses of intravenous immunoglobulin over the next few days. It did its job — his platelet count began to inch back toward normal, going from 2 to 6 to 15 to 30 to 60. The patient hadn’t felt sick since he got to the hospital, and the blood in his urine and the sores in his mouth cleared up after the first dose of immunoglobulin.
With his platelet counts improving — though still far from normal — the patient was safe (and eager) to leave the hospital. Even after he left, Fishman monitored the labs for results. It wasn’t toxoplasmosis. It wasn’t acute H.I.V. Finally, they got their answer: He had cat-scratch fever, an infection caused by a bacterium called Bartonella henselae. By then the patient’s symptoms were long gone. Even the swollen lymph node was barely visible.
A few weeks later, a test revealed that the young man’s platelets were back to normal. He still wonders if there is a genetic connection from his mother involved in all this. She has ITP that has lasted for years. She has to get infusions of immunoglobulin when her platelets drop. Was it just a coincidence that he got this, too? It’s a question for his mother’s hematologist. But he thinks it’s kind of cool that it’s all in the family.
Lisa Sanders, M.D., is a contributing writer for the magazine. Her latest book is “Diagnosis: Solving the Most Baffling Medical Mysteries.” If you have a solved case to share, write her at [email protected].