Nontuberculous mycobacteria (NTM) infections in cystic fibrosis are difficult to treat and becoming increasingly common. Therefore, it is one of the Cystic Fibrosis Foundation's highest priority antimicrobial areas. Common NTM infections in people with CF include Mycobacterium abscessus (M. abscessus) and Mycobacterium avium complex (MAC). Recognizing the need to better understand how to diagnose and treat these infections, the Foundation developed the NTM Consortium, a network of 10 care centers with expertise in studying and treating NTM infections and relatively large populations of individuals infected with NTM.
The consortium is facilitating two large studies to standardize the diagnosis and treatment of NTM infections in CF. The current diagnosis and treatment plans are based on published clinical practice guidelines sponsored by the Foundation and the European Cystic Fibrosis Society. People with CF with at least one positive NTM culture in the past two years are eligible for the PREDICT study. Those who enroll in this study have multiple respiratory cultures over time and undergo routine testing. Clinicians follow a decision tree to evaluate and treat other conditions that could be affecting the patient's health. Then, they determine if a patient meets diagnostic criteria for NTM lung disease and is likely to benefit from therapy. The determination of NTM lung disease is the trigger to discuss antimicrobial treatment and enrollment in the PATIENCE study.
In the PATIENCE study, clinicians use a detailed plan — or protocol — based on consensus recommendations to treat patients and monitor them to see how well the treatment plan works to reduce their symptoms and clear the NTM from the lungs. This standardized treatment approach will serve as a comparison for new antibiotics and treatment protocols.
The consortium of sites with expertise in NTM also creates a network of clinics where potential NTM therapies can be tested in future clinical trials. Currently, some sites within the consortium are seeking people with CF with NTM infections as volunteers for a clinical trial of inhaled molgramostim. Sites within the consortium will also participate in future studies testing novel antimicrobials in patients with NTM infections.
In 2018, about 13 percent of people with CF in the Foundation's Patient Registry cultured positive for NTM, and over the past five years 20 percent of those tested have had at least one positive culture. However, most people who have NTM found in their respiratory cultures do not go on to have NTM-related health problems.
NTM disease is a condition that clinicians diagnose in an individual when NTM is present in more than one culture, and the NTM appears to be causing illness — weight loss, decreased energy, chronic fevers, and night sweats — or a more rapid decline in that person's lung health than would be expected normally in CF. The diagnosis can include a computed tomography (CT) scan of the chest to look for a characteristic picture that suggests the infection is causing damage to the lungs. (Even with a CT scan, it can be difficult to distinguish NTM lung disease from the normal findings seen in CF lung disease in people who do not have NTM lung disease.)
NTM are resistant to many antibiotics and when treatment is required, it can be complicated and long, sometimes involving months of IV antibiotic treatment. Usually three or four antibiotics (IV, nebulized, and oral) are used together in combination to treat NTM. Unfortunately, treatment is not always successful, and there must be close monitoring to avoid significant side effects, such as hearing loss and problems with kidney function.
The following sites are part of the NTM consortium.
|University of Michigan, Michigan Medicine Pediatric Care Center||Ann Arbor, Mich.|
|Johns Hopkins Cystic Fibrosis Adult Care Center||Baltimore, Md.|
|The Children's Hospital of Alabama, Pediatric Care Center||Birmingham, Ala.|
|University of North Carolina at Chapel Hill Adult Care Center||Chapel Hill, N.C.|
|University of Texas Southwestern Adult Care Center||Dallas, Texas|
|National Jewish Health Adult Care Center||Denver, Colo.|
|Children's Hospital Colorado Pediatric Care Center||Aurora, Colo.|
|Children's Hospital of New York Pediatric Care Center||New York, N.Y.|
|University of Washington Medical Center Adult Care Center||Seattle, Wash.|
|Seattle Children's Hospital Pediatric Care Center||Seattle, Wash.|