As infectious bacteria become even more resistant to antibiotics, chronic disease patients with weakened immune systems are in particular danger
Microbiologists and clinical laboratory managers in the United States may find it useful to learn that exceptionally virulent strains of bacteria are causing increasing numbers of cancer patient deaths in India. Given the speed with which infectious diseases spread throughout the world, it’s not surprising that deaths due to similar hospital-acquired infections (HAIs) are increasing in the US as well.
Recent news reporting indicates that an ever-growing number of cancer patients in the world’s second most populous nation are struggling to survive these infections while undergoing chemotherapy and other treatments for their cancers.
In some ways, this situation is the result of more powerful antibiotics. Today’s modern antibiotics help physicians, pathologists, and clinical laboratories protect patients from infectious disease. However, it’s a tragic fact that those same powerful drugs are making patients with chronic diseases, such as cancer, more susceptible to death from HAIs caused by bacteria that are becoming increasingly resistant to those same antibiotics.
India is a prime example of that devastating dichotomy. Bloomberg reported that a study conducted by Abdul Ghafur, MD, an infectious disease physician with Apollo Hospitals in Chennai, India, et al, concluded that “Almost two-thirds of cancer patients with a carbapenem-resistant infection are dead within four weeks, vs. a 28-day mortality rate of 38% in patients whose infections are curable.”
This news should serve as an alert to pathologists, microbiologists, and clinical laboratory leaders in the US as these same superbugs—which resist not only antibiotics but other drugs as well—may become more prevalent in this country.
‘We Don’t Know What to Do’
The dire challenge facing India’s cancer patients is due to escalating bloodstream infections associated with carbapenem-resistant enterobacteriaceae (CRE), a particularly deadly bacteria that has become resistant to even the most potent carbapenem antibiotics, generally considered drugs of last resort for dealing with life-threatening infections.
Lately, the problem has only escalated. “We are facing a difficult scenario—to give chemotherapy and cure the cancer and get a drug-resistant infection and the patient dying of infections.” Ghafur told Bloomberg. “We don’t know what to do. The world doesn’t know what to do in this scenario.”
Ghafur added, “However wonderful the developments in the field of oncology, they are not going to be useful, because we know cancer patients die of infections.”
The problem in India, Bloomberg reports, is exacerbated by contaminated food and water. “Germs acquired through ingesting contaminated food and water become part of the normal gut microbiome, but they can turn deadly if they escape the bowel and infect the urinary tract, blood, and other tissues.” And chemotherapy patients, who likely have weakened digestive tracts, suffer most when the deadly germs reach the urinary tract, blood, and surrounding tissues.
“Ten years ago, carbapenem-resistant superbug infections were rare. Now, infections such as carbapenem-resistant klebsiella bloodstream infection, urinary infection, pneumonia, and surgical site infections are a day-to-day problem in our (Indian) hospitals. Even healthy adults in the community may carry these bacteria in their gut in Indian metropolitan cities; up to 5% of people carry these superbugs in their intestines,” Ghafur told The Better India.
What are CRE and Why Are They So Deadly?
CRE are part of the enterobacteriaceae bacterial family, which also includes Escherichia coli (E. coli) and Klebsiella pneumoniae. CRE, according to the Centers for Disease Control and Prevention (CDC), are considered “antibiotic-resistant” because antibiotic agents known as carbapenems are becoming increasing less effective at treating enterobacteriaceae.
In fact, a 2018 study conducted by the All India Institute of Medical Sciences (AIIMS) in New Delhi, which was published in the Journal of Global Infectious Diseases (JGID), found that bloodstream infections due to CRE were the “leading cause” of illness and death in patients with hematological malignancies, such as leukemia.
“These patients receive chemotherapy during treatment, which lead to severe mucositis of gastrointestinal tract and myelosuppression. It was hypothesized that the gut colonizer translocate into blood circulation causing [bloodstream infection],” the AIIMS paper states.
US Cases of C. auris Also Linked to CRE
Deaths in the US involving the fungus Candida auris (C. auris) have been linked to CRE as well. And, people who were hospitalized outside the US may be at particular risk.
The CDC reported on a Maryland resident who was hospitalized in Kenya with a carbapenemase-producing infection, which was later diagnosed as C. auris. The CDC describes C. auris as “an emerging drug-resistant yeast of high public concern … C auris frequently co-occurs with carbapenemase-producing organisms like CRE.”
Drug-resistant germs are a public health threat that has grown beyond overuse of antibiotics to an “explosion of resistant fungi,” reported the New York Times (NYT).
The NYT article states that “Nearly half of patients who contract C. auris die within 90 days, according to the CDC. Yet the world’s experts have not nailed down where it came from in the first place.”
Cases of C. auris in the US are showing up in New York, New Jersey, and Illinois and is arriving on travelers from many countries, including India, Pakistan, South Africa, Spain, United Kingdom, and Venezuela.
Since antibiotics are used heavily in agriculture and farming worldwide, the numbers of antibiotic-resistant infections will likely increase. Things may get worse, before they get better.
Pathologists, microbiologists, oncologists, and clinical laboratories involved in caring for patients with antibiotic-resistant infections will want to fully understand the dangers involved, not just to patients, but to healthcare workers as well.
—Donna Marie Pocius