Catching the ID Bug

Mark Crislip, MD


May 02, 2011

In medical school, I was planning to pursue primary care when I landed in an infectious diseases (ID) rotation at the Veterans Affairs hospital in Portland, Oregon. The cardiology rotation I wanted was full, and looking at the elective list I thought, "What the hell, I'll try ID." All too often in my life, serendipity has led to life-changing circumstances. (Sometime I will tell you the story of how I met my wife.)

As a medical student I was amazed by the pathology in ID. A patient with mitral valve endocarditis caused by Staphylococcus aureus required acute valve replacement. A person with Pseudomonas meningitis from urosepsis died. I remember, like it was yesterday, the thin green slime of bacteria and pus covering the patient's brain at autopsy.

As a student, I was also impressed with my attending's breadth and depth of medical knowledge. Unlike my other attendings, who often seemed slightly bored and were going through the motions, the ID doctors were fascinated with medicine. ID doctors, then and now, get excited about a great case. I was hooked. As an intern I did an ID rotation and my addiction was confirmed. ID was the life for me, and I have never looked back. Including my fellowship, I have been an ID physician for 24 years.

I am the sole ID doctor at 3 hospitals and spend 90% of my time seeing acutely ill inpatients and working on infection control. My outpatient practice is 1 hour, 3 days per week, and because of institutional support I have no overhead. ID is considered similar to plumbing and electricity, a necessary part of the hospital infrastructure. That is a good thing in Portland, because no ID doc has ever been able to survive financially on consult income alone.

What are the characteristics of my ID practice?

Novelty. I am usually called to see the difficult, obscure, or confusing cases, such as endocarditis, meningitis, or fever of unknown origin. It is rare to see the mundane or routine while practicing inpatient ID. ID is for those who thrive on novelty, not those who prefer the security of the routine. I am never bored with work; no one uses the term "great case" more frequently than an ID doc. The upside and downside are you are rarely comfortable with your knowledge base, and researching on Google and PubMed takes up a part of the workday.

Uncertainty. More often than not, I do not know what ails my patients. They remain sick and the studies fail to reveal a reason. Most of the time, they get better because of or in spite of my care, but if you are uncomfortable with uncertainty and making decisions with what seems to be inadequate information, ID may not be your best choice.

Breadth. In ID you have to be more than dimly aware of all of medicine, because infections can cross all specialties and many illnesses can mimic an infection.

Depth. The specialty requires not only a deep understanding of infections as they relate to patient care, but ID can interact with larger issues. Climate change, for example, will affect the epidemiology of many illnesses. The only truly holistic doctor is the ID doctor, who has to understand disease at the biochemical level and in the context of global infectious ramifications and everything in between. All other doctors are posers.

Despite the depth and breadth of knowledge that ID doctors acquire, such specialists are more likely to be ignored compared with other subspecialists. Many doctors labor under the delusion that they understand as much about infectious disease diagnosis and treatment as you do, so be prepared to be astounded at some of the approaches to ID you will encounter.

Intellectual curiosity. ID can be a specialty where you have to sort through clues to discover a diagnosis. A careful history is often the key to finding the correct diagnosis. Every once in a while, I will make an obscure diagnosis no one else considered, resulting in an unrivaled ego boost. For those who like to ask "Why?", ID offers endless opportunities to explore the interactions of infections and human society. This week, for example, I learned why stink bugs lead to Enterobacter infections in heroin users. If you are the type who takes time to discover on your own why this is so, ID may be your field. If you are irritated that I did not hand you the answer, perhaps cardiology is in your future.

A great working environment. Lazy, stupid people do not, as a rule, work in acute care hospitals. My colleagues (MD, DO, RN and all the other letters) are smart, hard-working, caring people, and a joy to work with. Working at a teaching hospital, I enjoy the opportunity to warp, er, I mean, guide young physicians and educate them about the most interesting field in medicine. (That said, only a handful of residents I have counseled in the past 20 years have chosen a career in ID, so I wonder if I am a positive or negative influence.)

No procedures. That is a benefit; it has been 20 years since I needed to wear a pair of sterile gloves.

No long-term care. This can be both a benefit and a detriment. In ID, most of your patients are cured and no longer need your care. Unfortunately you do not get the long-term satisfaction of taking care of patients and building relationships. On the other hand, you do not get saddled with the borderline drug seeker. These last 2 lead to:

Worst reimbursement in medicine. Really. If your goal is money, stay away from ID. I make, in private practice billing, about one third of what the average internist makes, but I do not think Portland is representative with what is reported on the interwebs.

For me, ID was the perfect choice for a career in medicine. I like problem solving and curing my patients. I like novelty -- being easily bored -- and am comfortable with uncertainty. There is no bigger ego boost than making the obscure diagnosis everyone missed. I like the controlled chaos of inpatient medicine and prefer the lack of long-term care and procedures. At 53, I know that there are more important things in life than money.

Should you go into ID? I don't know. The important thing is finding an area of medicine that you enjoy and that suits your temperament. Medicine is often a consuming profession, and if you are going to spend most of your waking hours practicing it, you should enjoy what you do.

To follow Dr. Crislip's musings as an ID specialist, visit

Related Content:

What I Have Learned About Infectious Diseases With My Sleeves Rolled Up

Molecular Diagnostics Overview and Focus on Infectious Diseases: An Expert Interview With Wayne W. Grody, MD, PhD

Spores and More: An ID Doc's Take on Infections (blog)

Host-Pathogen Passages (blog)

Preventing Infections: Spreading the Word (blog)


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