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Three diagnoses you don't want to miss

August 2017
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Published in the August 2017 issue of Today’s Hospitalist

BACTERIAL MENINGITIS, spinal epidural abscess and necrotizing soft tissue infection are urgent conditions that hospitalists need to do a better job of diagnosing and treating. That’s in part because the consequences can be so dire.

“We need to recognize these and manage them well so patients can get the best care and outcomes,” explained James Pile, MD, a hospitalist and infectious diseases specialist at Cleveland’s MetroHealth Medical Center, speaking at this year’s Society of Hospital Medicine annual meeting.

As Dr. Pile noted, hospitalists need to step up their care for these conditions for another reason: to make sure they don’t end up as psychological “second victims” in the event of delayed diagnosis and an associated catastrophic outcome.

“Every hour counts with bacterial meningitis.”

~ James Pile, MD
MetroHealth Medical Center

Finally, he pointed out, prompt diagnosis and appropriate management of these diseases will help physicians avoid malpractice suits: “All three are associated with litigation due to diagnostic delay.” He described several myths surrounding these conditions and the latest evidence to help expedite patients’ access to lifesaving care.

Bacterial meningitis
“Until fairly recently, there was still debate over whether a few hours’ delay in giving antibiotics for bacterial meningitis really makes a difference,” Dr. Pile said. But studies—including one in the November 2006 issue of Critical Care Medicine—”have convinced us that time is brain. Every hour counts with bacterial meningitis.”

Mounting evidence also indicates ways that hospitalists can speed up diagnosis and treatment. High-quality evidence, for instance, argues that clinicians may not have to wait for head-CT results before performing a spinal tap and starting antibiotics.

For patients who meet low-risk criteria, including those who are younger, have a normal neuro exam, are not immunocompromised and haven’t had a recent seizure, “we can feel quite comfortable proceeding directly to the lumbar puncture,” he said.

A study published in the April 15, 2015, issue of Clinical Infectious Diseases evaluated national guidelines revised in Sweden in 2009, in which altered mental status and recent seizures were removed as contraindications to performing lumbar puncture without obtaining a CT scan in patients with suspected bacterial meningitis. Study authors found that “mortality for bacterial meningitis, which was already low at 12%, fell to an amazingly low 7%” after the guideline revision, said Dr. Pile. (The mortality rate in most developed countries averages between 15% and 20%.)

Dr. Pile isn’t fully convinced that those guidelines are ready for prime time in the U.S. “But the Swedish experience suggests we are probably getting too many head CTs and thus delaying giving antibiotics,” he said.

Another take-home point: Always order blood cultures on any patient who may possibly have bacterial meningitis. “At least half the time,” he pointed out, “those cultures will be positive, even if you can’t get a timely CSF [cerebrospinal fluid] culture from a lumbar puncture. The blood cultures may nail the diagnosis for you.”

Hospitalists should also know that two of the classic signs of meningitis they were taught to look for—the Brudzinski sign and the Kernig sign—have never been “rigorously studied in the setting of bacterial meningitis,” he explained. Those signs have low sensitivity and shouldn’t be relied on to decide whether patients should undergo a lumbar puncture.

“The classic triad—fever, altered mental status, stiff neck—is seen slightly less than half the time. But importantly, almost all patients will have two of the three,” said Dr. Pile, citing a study in the July 14, 1999, issue of the Journal of the American Medical Association.

Performing a quick “jolt accentuation” test, where patients suspected of having meningitis swing their head from side to side and report whether that makes their headache worse, might also help you make the diagnosis.

And timing may matter when giving steroids to patients with pneumococcal meningitis. According to a landmark November 2002 study in the New England Journal of Medicine, “it is important to receive steroids with or before the first dose of antibiotics,” Dr. Pile said. “Give the steroids. Ask questions later. If it turns out not to be pneumococcal meningitis, you can stop them.”

Spinal epidural abscess
Hospitalists, particularly those who work in safety-net facilities, are seeing more spinal epidural abscesses (SEAs) due to increased injection drug use. Injecting drugs—along with diabetes, bacteremia from any source, alcohol abuse, end-stage renal disease, back surgery and anything that transgresses the epidural space—are risk factors for developing epidural abscesses. The majority, said Dr. Pile, are infected with S. aureus.

“It’s a tough diagnosis, and multiple studies have shown that, on average, it takes two or three trips for medical attention before the correct diagnosis is made,” he noted.

“We should think about this disease all the time in the appropriate setting to shift the curve toward earlier diagnosis.”

Don’t let the absence of a fever dissuade you from considering SEA, he said. “Patients are febrile only two-thirds of the time.” In a single-site study published in the June 2011 issue of Journal of Neurosurgery: Spine, clinicians found they could decrease the time to diagnosis if ED doctors followed an algorithm for patients presenting with back pain and SEA risk factors.

That algorithm used an elevated erythrocyte sedimentation rate (ESR) to determine whether at-risk patients should be sent for urgent MRIs. The center reduced its “diagnostic delay” from 84% before the algorithm was implemented to 10% after.

“The principle is simple,” Dr. Pile said. “If you see a person with central back pain and risk factors, suspect SEA and at least get a sed rate.” If the rate is normal, “you can stop. But if it’s elevated, seriously consider an MRI.”

He further noted that a CT scan is not nearly as sensitive as an MRI. “Be very careful before you discard this diagnosis based on a CT.”

In addition, when patients have an epidural abscess at one level of the spine, hospitalists should consider ordering imaging of the entire spine. According to an article in the Jan. 1, 2015, issue of The Spine Journal, “a clinically unsuspected epidural abscess at another level” exists 10% of the time.

Necrotizing soft tissue infection
It can be “really tough” to decide whether a patient has cellulitis or a necrotizing soft tissue infection such as necrotizing fasciitis, necrotizing myositis or necrotizing cellulitis, said Dr. Pile. The red flag is “pain out of proportion to the physical exam.” In addition, “the more toxic” patients are and the less appropriately they respond to antibiotics, “the more you should think about this scary disease.”

As shown in a study in the September 2011 issue of Critical Care Medicine, the most important risk factor for a bad outcome in these cases is “delayed diagnosis and delayed or inadequate surgery.” That is nearly the only risk factor that clinicians can do anything about.

The optimal imaging study to assist in diagnosis is probably a CT scan, Dr. Pile noted, ideally with intravenous contrast. An article in the May 2010 issue of JAMA Surgery found that a contrasted CT was 100% sensitive in diagnosing necrotizing fasciitis.

Plain films can also help on occasion, although the “time-honored way” to treat these patients is to call a surgeon right away to consider taking the patient to the operating room for direct inspection of the fascia. Now, however, “many younger surgeons are more comfortable with imaging.”

Nonetheless, Dr. Pile recommended “a low threshold to obtain surgical consultation” for patients with what appears to be a bad cellulitis. “If surgery is needed, you want to be aggressive.”

Deborah Gesensway is a freelance writer who covers U.S. health care from Toronto.