by Lisa Sanders
It is seen most commonly with gonorrhea (although it is unusual even in this disease), where it is often accompanied by fever and a rash. Lyme disease can also manifest this way, as can viruses like hepatitis and even HIV. But none of those seemed to fit. There were other, less likely possibilities. Rheumatoid arthritis can come on like this, as can lupus.
Justin Thompson, the intern working with me that month, had admitted Freeman for her earlier hospitalization. When I asked him about her, he wearily flipped through a stack of index cards that he pulled from his pockets. “Right. We tapped her knee and cultured her up,” he said, meaning that they’d drawn fluid from her knee, which should offer some clues, and had sent off some of the fluid, as well as her blood and urine, to check for evidence of infection. “I thought it was gonorrhea,” the intern stated flatly. “It’s not the way you usually see it, but gonorrhea can definitely cause this.”
The art of diagnosis can look a lot like profiling. Doctors constantly ask: Is a particular condition more common in men or women? Whites or blacks? The young or the old? In this way a doctor narrows the possible causes of a given illness in a given patient. Gonorrhea, then, was the most likely diagnosis for this young, sexually active, onetime prostitute. And while none of the tests had confirmed it, none ruled it out either.
But here she was again, knee gigantically swollen—again. This was not part of the disease profile, yet the intern working with me was undeterred. So much so that he had already ordered antibiotics to treat her presumed infection. Because she did not finish her course of antibiotics, the disease had been only partly treated; therefore, all she needed was more antibiotics. “Or maybe her boyfriend was the source,” he said, “and she’s been reexposed since getting treated. Or maybe she’s back on the street.”
These were all reasonable thoughts, but it was clear to me that we needed more evidence to make that diagnosis a second time. I thought we should hold the antibiotics until after we tapped the knee again and repeated her cultures.
I was also interested in the results of the blood tests from Freeman’s earlier hospitalization. I found a computer and tracked down her test results. Lyme was negative; hepatitis, negative; gonorrhea and syphilis, negative. In fact, there was only one set of positive results: the tests for recent strep infection along with several other blood tests consistent with a diagnosis of rheumatic fever. The problem is that rheumatic fever rarely occurs in these days of antibiotics, and when it does it is seen almost exclusively in children. It is practically unheard of for an adult to develop it. Even now that she met some of the criteria for the disease, such a diagnosis was hard to make. She simply didn’t fit the profile.
We went back to the patient. Had she had a sore throat recently? Yes. She’d had a sore throat a few weeks before, but she thought it could have been because of the crack. That convinced me. It now seemed clear that, as unlikely as it might have seemed initially, this young woman had rheumatic fever.
When we went back to the patient, she was dressed and ready to leave. Her knee, which had been red and hot and excruciatingly painful only twenty-four hours earlier, had improved significantly with no intervention. We scheduled her to see her doctor the following week. As she stood with her bag in hand, I tried to explain rheumatic fever and what it might mean to her, but she wasn’t listening.
“I’m better,” she announced, “so I’m gone.” I gave her her prescriptions and shook her hand, then watched as she limped down the hall, waved gaily from the door, and disappeared.
Recently I caught up with her doctor, who told me that Vera had gotten an echo to look for any signs of damage to her heart or their precious valves that direct the flow of blood through the organ. Everything was completely normal. And it made sense. Cardiac injury is very common in the children who get rheumatic fever; in adults the disease tends to “bite the joints and lick the heart,” causing joint pain but not the more significant cardiac lesions.
What has always stuck in my mind is the intern’s insistence on the diagnosis of gonorrhea even in the face of failed tests for that condition. Was he just being prejudiced against a minority woman with a history of behaviors not sanctioned by the larger society? Possibly, but I think the story is more complicated than that.
At first glance, patients might think that the ideal in diagnosis would be for a doctor to treat (and view) all of their patients identically—to be color, age, gender, and socioeconomically blind. We don’t want our looks to influence our doctor’s objective assessment of our health problems. And yet they must. Illnesses and diseases do not abide by our constitutionally required equal protection. Diseases do discriminate on the basis of race, gender, age, and even socioeconomic status.
To take a obvious example: the vast majority of breast cancer patients are women, so it is not wrong for a doctor to automatically drop that diagnosis down in her priority list when confronted with a male patient with a lump on his chest. A less obvious example is prostate cancer: black men are significantly more likely to get this type of cancer than men of other races—four times more likely, in fact, than Korean men, nearly twice as likely as men of European descent. So if a black man comes to a doctor complaining of urinary symptoms, a good doctor will automatically raise her level of suspicion for prostate cancer based solely on the color of the patient’s skin. In fact, it would be irresponsible of the doctor not to take race into account when considering this diagnosis.
Viewed in this light, the bias of the intern clinging to his suspicion of gonorrhea in a woman with a history of drug use and prostitution is not so egregious. Using drugs and having multiple sex partners, after all, are legitimately associated with an increased risk for sexually transmitted infections. What would be egregious is if the intern (or anybody else) settled on a diagnosis of gonorrhea based only on the color of the woman’s skin, her clothing, or some other aspect of her appearance or behavior, all of which have nothing to do with one’s risk of gonorrhea.
In other words, patients want doctors to be legitimately biased in their thinking and decision-making processes when struggling to find a diagnosis. Doctors should take into account any known associations that might help pin down the cause of an illness. But diagnoses can be missed when doctors apply false generalizations or close off diagnostic possibilities just because they are less likely in a certain group or population (e.g., “This can’t be HIV because the patient is elderly”). Research has shown that medical decision making is shaped by many of the same influences that distort other aspects of human interaction. Indeed, says one group of researchers, “despite their ‘objective’ medical training, physicians remain human actors, socially conditioned to engage in stereotyping, whether consciously or not.” In that respect, medical decision making can be a function of who the patient is as much as what the patient has.
Studies in social science have documented many nonmedical factors that influence medical decisions, including characteristics of the patient such as age, gender, socioeconomic status, race, or ethnicity. These can be important considerations in prioritizing possible diagnoses. But characteristics that have no obvious medical meaning—such as the presence or kind of health insurance, assertive personality type, or even physical attractiveness—have also been shown to play a role in how doctors make decisions about medical diagnosis and care. And even those factors that can affect the probability of disease in some cases, factors such as age and sex, are extraneous in many others.
One of the many careful experiments designed to tease out such influences illustrates this point. A set of videotaped doctor-patient encounters was created using professional actors. Scripts were created for male “patients” and female “patients” who complained of a set of cardiac symptoms. The scripts and all presenting details were identical in every respect aside from trivial changes in personal pronouns and the like. Two hundred fifty-six doctors practicing in both the United States and the United Kingdom were recruited for the study. They viewed either one or the other video scenario and were then asked a ser
ies of questions about what disorder they suspected, what treatments or recommendations they would suggest, and so on. Coronary heart disease (CHD) was chosen because it is the leading killer of both men and women, and although age-specific mortality rates are higher for men than women, twice as many women as men aged forty-five to sixty-four have undetected or “silent” CHD, which suggests that the true incidence between men and woman may be similar. This is a case, in other words, in which doctors should not apply a bias in their decision-making processes—here a gender bias.
The study results, however, clearly demonstrated just such a bias. Gender was found to have significant influence on all aspects of doctors’ diagnostic strategies; in each case women received less attention than men presenting with CHD symptoms. Doctors would ask men more questions than women (on average 7 and 5.7 questions, respectively) and perform more extensive examinations for men than women (5.1 compared to 4.3 parts of the body or body systems would be examined, respectively). CHD was mentioned as a possible diagnosis for more men than women (95 and 88 percent, respectively), and doctors had significantly higher certainty of CHD for male than female patients, 57 and 47 percent, respectively, on a scale of 0 (total uncertainty) to 100 percent (total certainty).
The study authors concluded: “Our findings indicate that women presenting with CHD symptoms are disadvantaged in primary care. Doctors provide a less thorough diagnostic search procedure than for men presenting with identical symptoms, and fewer women are given prescriptions appropriate for treating CHD.”
The impact of conscious or unconscious bias on the diagnostic thinking processes of doctors adds to the complexities of the entire doctor-patient experience. The best doctors acknowledge their vulnerabilities and try hard to retrain themselves or monitor themselves and their thinking processes as they move through any given diagnostic challenge.
The last type of cognitive error I want to talk about is what’s often called in the cognitive literature diagnostic momentum. This is a kind of medical groupthink in which once a diagnostic label is attached to a patient, it tends to become “stickier and stickier.” Doctors are taught in medical school that they should not simply accept a diagnosis given to a patient but should reevaluate the data for themselves before accepting or sometimes rejecting this diagnosis. That we should, as former president Ronald Reagan often exhorted (in a very different setting), “Trust but verify.” Rather than accept a previous diagnosis, doctors are supposed to start fresh by thinking things through for themselves. This, of course, is much easier said than done.
If a doctor is tired or in a hurry, she is far less likely to take the time to review all the test results and other evidence that went into the diagnosis. And even if she does expend the effort to do that, it’s difficult to not fall into the same well-defined disease pattern—potentially mistaken or not—that those who have seen the patient already have defined. But that kind of extra effort can sometimes pay off dramatically.
The Doctor of Last Resort
Graciela Moity spoke in a slow, husky vibrato. She sounded weary, discouraged. “I can remember clear as day when it all began,” she said. “It was just over a year ago. I woke up and felt like my legs were on fire.”
She was talking to Dr. David Podell—the most recent of a train of doctors who had evaluated the woman since that day she awoke in such pain. The three previous doctors couldn’t figure out what was going on. Their best guess was scleroderma, a disease caused by the overproduction of one of the connective tissues, collagen. The patient’s symptoms weren’t a great fit, but sometimes the disease could manifest itself in unusual ways. She was referred to Podell for confirmation of the diagnosis and treatment of this unusual autoimmune disorder.
With years of experience under his belt, Podell knew that when a patient has already been to a slew of specialists before arriving at your door, you need to approach the case with a different mind-set—with different assumptions. You know, for example, that whatever this patient has, it isn’t going to be obvious. Maybe it’s an unusual disease, known best by specialists—like scleroderma—or perhaps it’s an unusual presentation of a more common illness. In any case, it won’t be routine. In such situations, he knew, you had to start from scratch even if the patient comes to you with a diagnosis already made. He asked the woman to continue with her story, apologizing because he knew she had told and retold it so many times already in the past year.
She said that until that morning a year ago she had always been healthy. But the burning pain in her legs had been so intense that now she could hardly walk. And she had felt weak—especially in her left leg. She went to her regular doctor, but he didn’t know what to make of her symptoms and sent her to a neurologist. He examined her, sent off a dozen blood tests, and got a CT scan of her head and spine before sending her back to her internists, still undiagnosed.
Then she developed a cough. It was usually a dry, irritating cough, but occasionally she coughed up blood. Recently she felt out of breath with even slight exertion. This morning, she told Podell, she had to stop and rest during the short walk from the parking lot to his office. Her internist sent her to a pulmonologist because her lungs seemed clearly involved. He got a chest X-ray, then a chest CT, more blood tests, even a biopsy. The chest X-ray proved that her lungs were involved. In the normally black areas of the image over the air-filled lung tissue, there were faint patches of white. The biopsy showed inflammation but nothing more specific. He wasn’t sure what this was. He tried her on a variety of antibiotics. Finally he sent her back to her internist, suggesting the possibility of scleroderma.
Eventually her internist sent her to Podell, who is a rheumatologist—a specialist in diseases of connective tissues. Because connective tissues are found throughout the body, complex, multisystem illnesses are the rheumatologists’ bread and butter.
The patient was a slender woman with a mass of straight dark hair streaked with gray. Her skin was clear, but her eyes were puffy with fatigue, and she looked older than her fifty-three years. Examining her, Podell found few obvious signs of disease. Despite the cough and breathing problems, her lungs sounded clear. She had some mild weakness in her left hip, but other than that, her joints, skin, and muscles were all normal.
Podell could see why the previous doctors were puzzled. Her symptoms suggested that her illness involved the nervous system and the pulmonary system, which is an unusual pairing. Although scleroderma can affect both nerve and lung tissue, Moity didn’t have the classic thickening of the skin that is the hallmark of that disease. Could this be an atypical form of scleroderma? Or was it something else altogether?
Could this be Sjögren’s syndrome, a disease in which the immune system mistakenly attacks a patient’s fluid-producing glands? Sjögren’s can affect the lungs and sometimes spreads to the nervous system. Patients with Sjögren’s usually complain of painful eyes or a dry mouth, and this patient had mentioned that her mouth was dry.
Podell ordered blood tests to look for evidence of Sjögren’s. He assured the patient that he would do all he could to figure out what was going on, but that it would take a bit more time. Looking defeated, Graciela Moity made an appointment to return in a couple of weeks and trudged out toward the parking lot.
Podell wanted to examine the patient’s extensive medical record, especially the tests and results obtained by the other doctors. He didn’t read the records in advance in complicated cases. He felt it was important to take in the information without any preconceived notions about what was going on. But at the end of the day Podell sat down with her thick chart and went through every page. When you are the last in a string of practitioners, one of your most important jobs is to review each piece of the puzzle with fresh eyes, questioning every assumption and double-checking the reported results. In complex cases like this, the answer is sometimes already there, just waiting to be noticed.
A long list of blood tests had been done. Several suggested an inflammatory process, but none identified the cause.
The patient also had MRIs of her head and spine, as well as a CT scan of the chest. Podell was particularly interested in the chest CT, which showed something he could not have detected in his physical exam: faint, cloudy patches throughout both lungs. He wasn’t an expert in interpreting CT scans, so he called in a radiologist to look them over. But the colleague merely confirmed what Podell could already see: cloudy areas showed the presence of fluid in both lungs. Etiology: unknown.
The patient had also had a lung biopsy. The pathology report said there was evidence of inflammation but, like the blood tests, revealed nothing of the cause. But, again, Podell sought an expert opinion—in this case from the pathologist Tom Anderson. Podell and Anderson sat at a double-headed microscope in the pathology lab, scanning slides that held the biopsy samples. The first slide showed evidence of extensive inflammation, Anderson agreed, but nothing more. As he zipped across the second slide, Anderson reported that again he saw lots of inflammation. Suddenly he stopped. He quickly flipped the microscope lens to zoom in tight on one group of cells that formed a cluster, quite different in appearance from the cells around it.
“That looks like a granuloma,” he said.
These distinctive cell formations are characterized by groups of giant cells up to a hundred times larger than normal cells. They are seen in the lungs only in a few diseases—most commonly sarcoidosis (known more commonly as sarcoid) and tuberculosis. Podell almost laughed out loud. At last, the needle had fallen from the haystack. He picked up the phone and called the patient.
“I know what’s going on,” he told her. “I can explain everything.”
The culprit, Podell explained, was almost certainly sarcoid, a mysterious chronic disease characterized by inflammation of tissues that often display the unusual granuloma collections of cells. The disease usually affects the lungs, but in one third of cases can attack other parts of the body as well, including (rarely) the nervous system. He told her she would need to be tested for tuberculosis, as that disease can also cause granulomas, but he was confident that’s not what she had. She had none of the common symptoms of TB such as night sweats, weight loss, or fever. No, Podell said, this is overwhelmingly likely to be sarcoid.