This Medical Mystery is courtesy of Dr Allison Bond, a resident in internal medicine at Massachusetts General Hospital. It has been adapted from the original article in STAT News https://www.statnews.com/2017/04/17/postoperative-infection-medical-mystery/
If you have a similar Medical Mystery in which pathology plays a similar role, email us at info@knowpathology.com.au
Background
By the time Patient X attended Dr. Hogan’s office, it had been three months since she had felt like herself. Previously completely healthy, the 25-year-old woman had been plagued by shaking chills, fevers, and unremitting fatigue, barely able to drag herself to work. Most troubling, though, was the thin yellow fluid draining from her thighs and the undersides of her breasts.
Patient X’s symptoms had started a little over two weeks after she underwent an operation in the Dominican Republic. The cosmetic surgery – known colloquially as a Brazilian butt lift – had entailed sucking fat out of the belly and low back, then injecting it into the buttocks and thighs. She also underwent breast augmentation.
The clinic had looked pristine. She received a weeklong course of antibiotics after the operation, and the surgical wounds seemed to be healing well. As instructed by the doctor, she kept the incisions clean, and didn’t swim or use hot tubs.
Just a few days after she returned home to Boston, she started draining the fluid from her breasts and thighs.
“My first day back at work, I noticed my shirt felt wet,” Patient X said in an interview with STAT. “I looked in my bra and saw this thin liquid.” Some days, the towels she stuffed into her bra to absorb the fluid became soaked within an hour or two.
Around this same time, Patient X noted large bruises on her legs; these became red and excruciatingly painful, sometimes opening up at night and releasing the same thin fluid.
She’d become extremely fatigued — falling asleep at 5 p.m. some days — and was spiking fevers. She was also losing weight without trying to.
Patient X went to see her General Practitioner, who took samples of this draining fluid and prescribed antibiotics. Over the next few months, the samples would show just a sprinkling of the types of bacteria that normally live on the skin, such as Staphylococcus aureus. Doctors prescribed Patient X various types of antibiotic pills, and although her symptoms sometimes improved temporarily, they always returned.
Alarmingly, the silicone breast implants also eroded through her skin about a month after her surgery; they were visible through the incision. The implants were removed at a hospital; the surgeon told Patient X he thought they might be infected. Although the wounds were rinsed with an antibiotic called cefazolin, no samples were sent for microbiological studies.
Putting it all together
By August 2016, Patient X was fed up. She was then seen by Hogan, a fellow in infectious diseases at Massachusetts General Hospital.
On exam, Hogan noted that the opening in the fold beneath her left breast was draining something that was thinner than pus, but was nevertheless indicative of infection. He was alarmed at the way the infection had bored holes through Patient X’s flesh.
“She had multiple draining ulcers separate from the surgical sites,” said Hogan, who has followed Patient X closely ever since that first appointment. “It looked like a deep infection from within the soft tissue” making its way to the skin, he said.
Full blood count showed slightly high white blood cell and platelet counts, both of which can be high when there’s an infection or inflammation. Her kidney and liver tests were normal. Looking over Patient X’s imaging, Hogan noticed what looked like areas of infection in the parts of her breasts seen in a CT scan of her chest. Hogan thought it might show some smudges indicating a collection of infected fluid.
Hogan felt confident Patient X was infected from the surgery. He ruled out other possible sources of infection: Patient X had no pets. She was not a drug user and never had been. She hadn’t travelled out of the country other than her recent trip for the cosmetic surgery.
The question was which microbe was causing the infection, and why the previous treatments hadn’t gotten rid of it.
Something didn’t quite fit
Patient X’s General Practitioner might have treated her with the wrong antibiotics, or for too short a time, for a commonplace bacterial infection. There also might be a walled-off collection of pus inside of her body that the antibiotics couldn’t reach. Yet if that were the case, the samples collected from the wounds should have grown a lot more bacteria; a mix of a few bugs commonly found on the skin wasn’t exactly a slam-dunk for an infection that just wouldn’t quit.
The other possibility, he thought, was an infection different from the usual ones after surgery in the United States. As opposed to fast-moving staph and strep infections, for example, bacteria in the mycobacterial family could cause chronic, draining infections.
At the forefront of his mind were Mycobacterium fortuitum, Mycobacterium chelonae, and Mycobacterium abscessus, which can cause infections of the skin and underlying tissue and are cousins to Mycobacterium tuberculosis, which causes tuberculosis. M. abscessus can cause lung infections, and more rarely meningitis or infections in the brain. Special material is needed to grow mycobacterial species, so it wouldn’t be surprising that previous pathology tests hadn’t revealed these bacteria.
Hogan sent samples of the fluid from her legs and chest for analysis for fungi, mycobacteria, and nocardia, another rare cause of chronic bacterial infections. He also ordered breast and thigh ultrasounds to look for the hidden pockets of infection possibly seen on the CT scan. Finally, he switched Patient X’s antibiotic to better treat staph on the off-chance that this was the cause of her symptoms.
At last, a diagnosis
Hogan and Dr. Raj Gandhi, his more senior colleague on the case, were not surprised when the cultures revealed Mycobacterium abscessus. The defining characteristics of the case — from the chronicity, to the sites and nature of fluid drainage, to the preceding surgery, to the recalcitrance of the infection to many antibiotics — pointed to an infection by this bug.
“It really was classic for mycobacterial disease,” Hogan said.
The tempo of the infection — never disappearing, but never ramping up to the extent that Patient X developed a life-threatening systemic infection — was also typical. If the staph isolated from her wounds had been causing the infection, for example, Patient X likely would have become much sicker, much more quickly — progressing over days, instead of lingering for months. The staph bacteria in her samples were innocent bystanders, not the root of her infection.
Another clue pointing to M. abscessus was the way more and more wounds kept popping up; run-of-the-mill postoperative infections tend to solely entail the area where the surgery was originally performed.
For Patient X, getting a diagnosis after months of searching felt like a breakthrough.
“I was relieved, because at least I had an answer,” she said.
