Three patients developed extrapulmonary Mycobacterium abscessus infections subsequent to receiving embryonic stem cell injections in Mexico, according to a recent report published in the MMWR Morbidity and Mortality Weekly Report. This situation underscores the need for healthcare professionals to advise individuals who are contemplating traveling abroad for medical treatments, a phenomenon known as medical tourism, of the potential infection risks associated with such decisions.
Between 2022 and 2023, these three patients were admitted to different hospitals in Colorado, suffering from extrapulmonary M. abscessus infections which arose after their visit to Mexico for stem cell therapies. These clinical findings were reported to both state and public health departments by the physicians who treated these patients.
The first case involved a female patient, aged between 30 and 39, who sought intrathecal donor embryonic stem cell injections in Mexico as a treatment option for multiple sclerosis. This patient was subsequently hospitalized in Colorado due to symptoms including fever and headache – alarms signaling the potential onset of meningitis. An analysis of her cerebrospinal fluid revealed neutrophilic pleocytosis and cultured specimens grew M. abscessus.
The two remaining cases entailed males aged between 60 and 69 years, who went to different clinics in Mexico to receive donor embryonic stem cell injections for psoriatic arthritis and osteoarthritis, respectively. Both patients developed post-treatment infections. The second patient was diagnosed with an osteoarticular infection in his right elbow while the third patient suffered from infections in both knees.
Following these cases, infectious disease specialists obtained the initial isolates from the first and second patients to conduct whole-genome sequencing and phylogenetic analysis. The results disclosed that the isolates were, in fact, clonal M. abscessus subspecies massiliense with just a single nucleotide polymorphism discrepancy in the core genomes. It was found that despite receiving treatment at different clinics in Mexico, all patients were infected by a single clone, alluding to a shared source of infection.
The authors of the study emphasized the need for awareness regarding the historical connection between stem cell treatments and bacterial infections and the associated risks pertaining to procedure-related infections in the sphere of medical tourism. Healthcare providers and public health agencies have been urged to remain vigilant towards similar cases and cognizant about the risk for M. abscessus infections resulting from stem cell treatment indications that have not yet been endorsed by the Food and Drug Administration. It is noted that several study authors declared affiliations with pharmaceutical and biotech companies, as well as device manufacturers.