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Variation in bacterial drug susceptibility tied to TB relapse risk
Higher pretreatment drug concentrations close to a resistance breakpoint for susceptibility were associated with greater relapse risk in TB, based on data from 54 patients who relapsed and 63 who were treated and cured.
“We postulated that drug-susceptible Mycobacterium tuberculosis might have a graded spectrum of susceptibilities that could be used to determine the risk of relapse,” wrote Roberto Colangeli, PhD, of Rutgers University, Newark, N.J., and his colleagues.
In a study published in the New England Journal of Medicine, the researchers examined pretreatment bacterial isolates from adults with TB who had experienced relapse and those who were cured. Using these isolates, they identified the minimum inhibitory concentration (MIC) – the lowest concentration of the drug that prevents visible bacterial growth in culture – for isoniazid and rifampin.
Overall, after controlling for other potential relapse risk factors, higher pretreatment MIC values for both isoniazid and rifampin were associated with an increased relapse risk. For isoniazid, the average MIC below the breakpoint was 0.0334 mcg/mL for relapsed patients and 0.0286 mcg/mL for cured patients. For rifampin, the average MIC below the breakpoint was 0.0695 mcg/mL for relapsed patients and 0.0453 mcg/mL for cured patients. The higher values for the relapsed versus cured patients were represented by factors of 1.17 and 1.53 for isoniazid and rifampin, respectively.
The average age of the patients was 41 years; 83% were men, and 35% were non-Hispanic white.
The study findings were limited by several factors, including the small sample size, retrospective design, and inability to test MIC values from primary cultures versus subcultures, the researchers wrote. However, the results suggest an impact of MIC values on treatment outcomes, and “additional studies that are performed in larger, well-defined prospective cohorts and that include MIC testing of pretreatment culture isolates will be useful to better validate these findings,”
The study was funded by the National Institute of Allergy and Infectious Diseases. Dr. Colangeli reported no financial conflicts. Dr. Alland disclosed funding from Cepheid and several current and pending patents in the United States and Europe, with some royalties paid to Cepheid.
SOURCE: Colangeli R et al. N Engl J Med. 2018;379:823-33.
Although standard four-drug therapy has been shown to cure 90% of patients in several clinical trials, patients do relapse for reasons such as poor treatment adherence and “variations in the characteristics of the infected patients or the infecting pathogens,” wrote Eric J. Rubin, MD, in an accompanying editorial (N Engl J Med. 2018;379:882-3).
Current antibiotic susceptibility thresholds are often set by committees using models, said Dr. Rubin. “Given the uncertainties in modeling, as has been seen in clinical studies, these breakpoints can be imperfect predictors of treatment response.”
Dr. Rubin proposed that minimum inhibitory concentration (MIC) concentrations could be an alternative to in vitro testing as a predictor of treatment response.
“The clinical laboratory provides us not only with a breakpoint interpretation but also with raw data, a quantitative assessment of MIC values,” he noted. “These values can be thought of more as probabilities of successful therapy than as absolute thresholds, a change in attitude that may dispel a false sense of security about the choice of regimen in the treatment of patients with tuberculosis.”
Dr. Rubin is affiliated with the department of immunology and infectious diseases at the Harvard School of Public Health, Boston. He had no relevant financial conflicts to disclose.
Although standard four-drug therapy has been shown to cure 90% of patients in several clinical trials, patients do relapse for reasons such as poor treatment adherence and “variations in the characteristics of the infected patients or the infecting pathogens,” wrote Eric J. Rubin, MD, in an accompanying editorial (N Engl J Med. 2018;379:882-3).
Current antibiotic susceptibility thresholds are often set by committees using models, said Dr. Rubin. “Given the uncertainties in modeling, as has been seen in clinical studies, these breakpoints can be imperfect predictors of treatment response.”
Dr. Rubin proposed that minimum inhibitory concentration (MIC) concentrations could be an alternative to in vitro testing as a predictor of treatment response.
“The clinical laboratory provides us not only with a breakpoint interpretation but also with raw data, a quantitative assessment of MIC values,” he noted. “These values can be thought of more as probabilities of successful therapy than as absolute thresholds, a change in attitude that may dispel a false sense of security about the choice of regimen in the treatment of patients with tuberculosis.”
Dr. Rubin is affiliated with the department of immunology and infectious diseases at the Harvard School of Public Health, Boston. He had no relevant financial conflicts to disclose.
Although standard four-drug therapy has been shown to cure 90% of patients in several clinical trials, patients do relapse for reasons such as poor treatment adherence and “variations in the characteristics of the infected patients or the infecting pathogens,” wrote Eric J. Rubin, MD, in an accompanying editorial (N Engl J Med. 2018;379:882-3).
Current antibiotic susceptibility thresholds are often set by committees using models, said Dr. Rubin. “Given the uncertainties in modeling, as has been seen in clinical studies, these breakpoints can be imperfect predictors of treatment response.”
Dr. Rubin proposed that minimum inhibitory concentration (MIC) concentrations could be an alternative to in vitro testing as a predictor of treatment response.
“The clinical laboratory provides us not only with a breakpoint interpretation but also with raw data, a quantitative assessment of MIC values,” he noted. “These values can be thought of more as probabilities of successful therapy than as absolute thresholds, a change in attitude that may dispel a false sense of security about the choice of regimen in the treatment of patients with tuberculosis.”
Dr. Rubin is affiliated with the department of immunology and infectious diseases at the Harvard School of Public Health, Boston. He had no relevant financial conflicts to disclose.
Higher pretreatment drug concentrations close to a resistance breakpoint for susceptibility were associated with greater relapse risk in TB, based on data from 54 patients who relapsed and 63 who were treated and cured.
“We postulated that drug-susceptible Mycobacterium tuberculosis might have a graded spectrum of susceptibilities that could be used to determine the risk of relapse,” wrote Roberto Colangeli, PhD, of Rutgers University, Newark, N.J., and his colleagues.
In a study published in the New England Journal of Medicine, the researchers examined pretreatment bacterial isolates from adults with TB who had experienced relapse and those who were cured. Using these isolates, they identified the minimum inhibitory concentration (MIC) – the lowest concentration of the drug that prevents visible bacterial growth in culture – for isoniazid and rifampin.
Overall, after controlling for other potential relapse risk factors, higher pretreatment MIC values for both isoniazid and rifampin were associated with an increased relapse risk. For isoniazid, the average MIC below the breakpoint was 0.0334 mcg/mL for relapsed patients and 0.0286 mcg/mL for cured patients. For rifampin, the average MIC below the breakpoint was 0.0695 mcg/mL for relapsed patients and 0.0453 mcg/mL for cured patients. The higher values for the relapsed versus cured patients were represented by factors of 1.17 and 1.53 for isoniazid and rifampin, respectively.
The average age of the patients was 41 years; 83% were men, and 35% were non-Hispanic white.
The study findings were limited by several factors, including the small sample size, retrospective design, and inability to test MIC values from primary cultures versus subcultures, the researchers wrote. However, the results suggest an impact of MIC values on treatment outcomes, and “additional studies that are performed in larger, well-defined prospective cohorts and that include MIC testing of pretreatment culture isolates will be useful to better validate these findings,”
The study was funded by the National Institute of Allergy and Infectious Diseases. Dr. Colangeli reported no financial conflicts. Dr. Alland disclosed funding from Cepheid and several current and pending patents in the United States and Europe, with some royalties paid to Cepheid.
SOURCE: Colangeli R et al. N Engl J Med. 2018;379:823-33.
Higher pretreatment drug concentrations close to a resistance breakpoint for susceptibility were associated with greater relapse risk in TB, based on data from 54 patients who relapsed and 63 who were treated and cured.
“We postulated that drug-susceptible Mycobacterium tuberculosis might have a graded spectrum of susceptibilities that could be used to determine the risk of relapse,” wrote Roberto Colangeli, PhD, of Rutgers University, Newark, N.J., and his colleagues.
In a study published in the New England Journal of Medicine, the researchers examined pretreatment bacterial isolates from adults with TB who had experienced relapse and those who were cured. Using these isolates, they identified the minimum inhibitory concentration (MIC) – the lowest concentration of the drug that prevents visible bacterial growth in culture – for isoniazid and rifampin.
Overall, after controlling for other potential relapse risk factors, higher pretreatment MIC values for both isoniazid and rifampin were associated with an increased relapse risk. For isoniazid, the average MIC below the breakpoint was 0.0334 mcg/mL for relapsed patients and 0.0286 mcg/mL for cured patients. For rifampin, the average MIC below the breakpoint was 0.0695 mcg/mL for relapsed patients and 0.0453 mcg/mL for cured patients. The higher values for the relapsed versus cured patients were represented by factors of 1.17 and 1.53 for isoniazid and rifampin, respectively.
The average age of the patients was 41 years; 83% were men, and 35% were non-Hispanic white.
The study findings were limited by several factors, including the small sample size, retrospective design, and inability to test MIC values from primary cultures versus subcultures, the researchers wrote. However, the results suggest an impact of MIC values on treatment outcomes, and “additional studies that are performed in larger, well-defined prospective cohorts and that include MIC testing of pretreatment culture isolates will be useful to better validate these findings,”
The study was funded by the National Institute of Allergy and Infectious Diseases. Dr. Colangeli reported no financial conflicts. Dr. Alland disclosed funding from Cepheid and several current and pending patents in the United States and Europe, with some royalties paid to Cepheid.
SOURCE: Colangeli R et al. N Engl J Med. 2018;379:823-33.
FROM THE NEW ENGLAND JOURNAL OF MEDICINE
Key clinical point: Risk of TB relapse increased with higher pretreatment minimum inhibitory concentration values for either isoniazid or rifampin.
Major finding: The higher values for the relapsed versus cured patients were represented by factors of 1.17 and 1.53 for isoniazid and rifampin, respectively.
Study details: The data come from a retrospective study of isolates from 54 patients with TB who relapsed and 63 who were treated and cured.
Disclosures: The study was funded by the National Institute of Allergy and Infectious Diseases. Dr. Colangeli reported no financial conflicts. Dr. Alland disclosed funding from Cepheid and several current and pending patents in the United States and Europe, with some royalties paid to Cepheid.
Source: Colangeli R et al. N Engl J Med. 2018;379:823-33.
RSV-related risk of hospitalization higher in Down syndrome patients
reported Andrea Beckhaus, MD, and Jose Castro-Rodriguez, MD, PhD, at the Pontificia Universidad Católica de Chile in Santiago.
Because DS is the most common chromosomal disorder, affecting 1 in every 800 children born worldwide, and respiratory infections are the leading cause of hospitalization in children with DS, especially during the first year of life, the results of this study are important and have considerable consequences for public health, the authors observed.
The economic burden on families of children with DS and the health care systems that treat them is, not surprisingly, significantly higher given their sevenfold higher need for supplemental oxygen therapy, threefold likely increased risk of ICU admission, fivefold higher likely need for ventilator support, and average increased length of hospital stay by nearly 5 days.
In the 15 years from 1997 to 2012, RSV-related hospital charges for infants with DS increased by nearly 80% from $10,141 (US dollars) to $18,217, compared with charges for infants not at high risk, which increased by more than 60% from $6,983 to $11,273 during the same period, according to a study (PLoS One. 2016;11[4]:e0152208).
Dr. Beckhaus and Dr. Castro-Rodriguez conducted their systematic review and meta-analysis to evaluate RSV-associated morbidity in children with DS. Following a search of four electronic data bases, a total of 12 studies published between 2004 and 2017 across 10 different countries were identified, including six in Europe, three in Asia, two in the United States, and one in Latin America. Altogether, 3,662 children with DS and 1,145,509 without DS were included in the review.
“Any potential strategy to reduce RSV infection (e.g., prophylaxis with monoclonal antibodies or new vaccines) in children with DS could decrease their morbidity and mortality,” the authors noted. Specifically, they cited the humanized monoclonal antibody palivizumab, which is used for prophylaxis against RSV. Palivizumab is known to reduce hospitalizations in children at high risk from comorbid conditions, including chronic lung disease, hemodynamically significant congenital heart disease (CHD), neuromuscular disease, immunodeficiency, and prematurity. At present, palivizumab is not recommended by the American Academy of Pediatrics for routine use to prevent RSV infection in patients with DS who are not already qualified for other reasons because there are insufficient data to recommend routine prophylactic use of the drug in children with Down syndrome.
The authors cited recent studies in Canada and Japan that may warrant further reconsideration of the AAP’s recommendations, however. A fourfold lowering of RSV-related hospitalizations was observed during the first 2 years of life among 532 children with DS receiving palivizumab who were included in a recent prospective Canadian study. The drug also was found to be safe and effective for preventing lower respiratory tract infections caused by RSV in a recent Japanese multicenter postmarketing surveillance study that evaluated palivizumab prophylaxis for RSV infection in 138 children with DS who did not have hemodynamically significant CHD; only 2 of the children treated required hospitalization.
“More cost-utility studies used to determine the efficacy of RSV immunoprophylaxis in this specific high-risk patient population need to be done,” Dr. Beckhaus and Dr. Castro-Rodriguez recommended.
The review was not without limitations. Not all of the studies included subgroups of participants with DS with CHD and without CHD or other additional risk factors. However, when only those studies were considered that had data for participants with DS without other risk factors, almost all results were similar.
One key strength of the study concerned the study methodology. Using the Newcastle–Ottawa scale, the risk of bias among the 12 studies was generally low, the total number of participants was considerably high, and the outcomes selected had importance for the patients and also public health implications. “It is important to remark that the vast majority of the outcomes that were analyzed had no or unimportant bias,” they said.
Dr. Beckhaus and Dr. Castro-Rodriguez had no relevant disclosures to disclose.
SOURCE: Beckhaus A et al. J Pediatrics. 2018;142(3):e20180225.
reported Andrea Beckhaus, MD, and Jose Castro-Rodriguez, MD, PhD, at the Pontificia Universidad Católica de Chile in Santiago.
Because DS is the most common chromosomal disorder, affecting 1 in every 800 children born worldwide, and respiratory infections are the leading cause of hospitalization in children with DS, especially during the first year of life, the results of this study are important and have considerable consequences for public health, the authors observed.
The economic burden on families of children with DS and the health care systems that treat them is, not surprisingly, significantly higher given their sevenfold higher need for supplemental oxygen therapy, threefold likely increased risk of ICU admission, fivefold higher likely need for ventilator support, and average increased length of hospital stay by nearly 5 days.
In the 15 years from 1997 to 2012, RSV-related hospital charges for infants with DS increased by nearly 80% from $10,141 (US dollars) to $18,217, compared with charges for infants not at high risk, which increased by more than 60% from $6,983 to $11,273 during the same period, according to a study (PLoS One. 2016;11[4]:e0152208).
Dr. Beckhaus and Dr. Castro-Rodriguez conducted their systematic review and meta-analysis to evaluate RSV-associated morbidity in children with DS. Following a search of four electronic data bases, a total of 12 studies published between 2004 and 2017 across 10 different countries were identified, including six in Europe, three in Asia, two in the United States, and one in Latin America. Altogether, 3,662 children with DS and 1,145,509 without DS were included in the review.
“Any potential strategy to reduce RSV infection (e.g., prophylaxis with monoclonal antibodies or new vaccines) in children with DS could decrease their morbidity and mortality,” the authors noted. Specifically, they cited the humanized monoclonal antibody palivizumab, which is used for prophylaxis against RSV. Palivizumab is known to reduce hospitalizations in children at high risk from comorbid conditions, including chronic lung disease, hemodynamically significant congenital heart disease (CHD), neuromuscular disease, immunodeficiency, and prematurity. At present, palivizumab is not recommended by the American Academy of Pediatrics for routine use to prevent RSV infection in patients with DS who are not already qualified for other reasons because there are insufficient data to recommend routine prophylactic use of the drug in children with Down syndrome.
The authors cited recent studies in Canada and Japan that may warrant further reconsideration of the AAP’s recommendations, however. A fourfold lowering of RSV-related hospitalizations was observed during the first 2 years of life among 532 children with DS receiving palivizumab who were included in a recent prospective Canadian study. The drug also was found to be safe and effective for preventing lower respiratory tract infections caused by RSV in a recent Japanese multicenter postmarketing surveillance study that evaluated palivizumab prophylaxis for RSV infection in 138 children with DS who did not have hemodynamically significant CHD; only 2 of the children treated required hospitalization.
“More cost-utility studies used to determine the efficacy of RSV immunoprophylaxis in this specific high-risk patient population need to be done,” Dr. Beckhaus and Dr. Castro-Rodriguez recommended.
The review was not without limitations. Not all of the studies included subgroups of participants with DS with CHD and without CHD or other additional risk factors. However, when only those studies were considered that had data for participants with DS without other risk factors, almost all results were similar.
One key strength of the study concerned the study methodology. Using the Newcastle–Ottawa scale, the risk of bias among the 12 studies was generally low, the total number of participants was considerably high, and the outcomes selected had importance for the patients and also public health implications. “It is important to remark that the vast majority of the outcomes that were analyzed had no or unimportant bias,” they said.
Dr. Beckhaus and Dr. Castro-Rodriguez had no relevant disclosures to disclose.
SOURCE: Beckhaus A et al. J Pediatrics. 2018;142(3):e20180225.
reported Andrea Beckhaus, MD, and Jose Castro-Rodriguez, MD, PhD, at the Pontificia Universidad Católica de Chile in Santiago.
Because DS is the most common chromosomal disorder, affecting 1 in every 800 children born worldwide, and respiratory infections are the leading cause of hospitalization in children with DS, especially during the first year of life, the results of this study are important and have considerable consequences for public health, the authors observed.
The economic burden on families of children with DS and the health care systems that treat them is, not surprisingly, significantly higher given their sevenfold higher need for supplemental oxygen therapy, threefold likely increased risk of ICU admission, fivefold higher likely need for ventilator support, and average increased length of hospital stay by nearly 5 days.
In the 15 years from 1997 to 2012, RSV-related hospital charges for infants with DS increased by nearly 80% from $10,141 (US dollars) to $18,217, compared with charges for infants not at high risk, which increased by more than 60% from $6,983 to $11,273 during the same period, according to a study (PLoS One. 2016;11[4]:e0152208).
Dr. Beckhaus and Dr. Castro-Rodriguez conducted their systematic review and meta-analysis to evaluate RSV-associated morbidity in children with DS. Following a search of four electronic data bases, a total of 12 studies published between 2004 and 2017 across 10 different countries were identified, including six in Europe, three in Asia, two in the United States, and one in Latin America. Altogether, 3,662 children with DS and 1,145,509 without DS were included in the review.
“Any potential strategy to reduce RSV infection (e.g., prophylaxis with monoclonal antibodies or new vaccines) in children with DS could decrease their morbidity and mortality,” the authors noted. Specifically, they cited the humanized monoclonal antibody palivizumab, which is used for prophylaxis against RSV. Palivizumab is known to reduce hospitalizations in children at high risk from comorbid conditions, including chronic lung disease, hemodynamically significant congenital heart disease (CHD), neuromuscular disease, immunodeficiency, and prematurity. At present, palivizumab is not recommended by the American Academy of Pediatrics for routine use to prevent RSV infection in patients with DS who are not already qualified for other reasons because there are insufficient data to recommend routine prophylactic use of the drug in children with Down syndrome.
The authors cited recent studies in Canada and Japan that may warrant further reconsideration of the AAP’s recommendations, however. A fourfold lowering of RSV-related hospitalizations was observed during the first 2 years of life among 532 children with DS receiving palivizumab who were included in a recent prospective Canadian study. The drug also was found to be safe and effective for preventing lower respiratory tract infections caused by RSV in a recent Japanese multicenter postmarketing surveillance study that evaluated palivizumab prophylaxis for RSV infection in 138 children with DS who did not have hemodynamically significant CHD; only 2 of the children treated required hospitalization.
“More cost-utility studies used to determine the efficacy of RSV immunoprophylaxis in this specific high-risk patient population need to be done,” Dr. Beckhaus and Dr. Castro-Rodriguez recommended.
The review was not without limitations. Not all of the studies included subgroups of participants with DS with CHD and without CHD or other additional risk factors. However, when only those studies were considered that had data for participants with DS without other risk factors, almost all results were similar.
One key strength of the study concerned the study methodology. Using the Newcastle–Ottawa scale, the risk of bias among the 12 studies was generally low, the total number of participants was considerably high, and the outcomes selected had importance for the patients and also public health implications. “It is important to remark that the vast majority of the outcomes that were analyzed had no or unimportant bias,” they said.
Dr. Beckhaus and Dr. Castro-Rodriguez had no relevant disclosures to disclose.
SOURCE: Beckhaus A et al. J Pediatrics. 2018;142(3):e20180225.
FROM PEDIATRICS
Key clinical point: Strategies to reduce RSV are needed to decrease morbidity and mortality in children with Down syndrome.
Major finding: Down syndrome children with RSV-related hospitalization had sevenfold higher need for supplemental oxygen therapy, threefold likely increased risk of ICU admission, fivefold higher likely need for ventilator support, and average increased length of hospital stay by nearly 5 days.
Study details: Systematic review and 12-study meta-analysis of 3,662 children with DS and 1,145,509 without DS.
Disclosures: The authors had no relevant financial disclosures.
Source: Beckhaus A et al. J Pediatrics. 2018;142(3):e20180225.
FDA warns against azithromycin in blood or lymph node cancers
The Food and Drug Administration has issued a in patients with blood or lymph node cancers who have received donor stem cell transplants.
This use of azithromycin can lead to increased risk of cancer relapse and death in this population. The FDA is continuing to review data and is expected to issue further recommendations.
Patients with blood or lymph node cancers are at an increased risk of bronchiolitis obliterans syndrome after donor stem cell transplant; although azithromycin is not approved for prevention of this condition, the antibiotic is sometimes prescribed for that purpose.
A French study of 480 patients was undertaken to assess the effectiveness of this prophylaxis but revealed the increased risk of relapse and death and was halted 13 months after completing enrollment. The rate of cancer relapse was 32.9% in the azithromycin group and just 20.8% in the placebo group; the 2-year survival rate was 56.6% in the azithromycin group and 70.1% in the placebo group (JAMA 2017;318[6]:557-66).
Bronchiolitis obliterans syndrome is marked by inflammation and scarring of the airways that leads to severe shortness of breath and dry cough. There are no known effective antibiotic treatments for prophylaxis of the condition, according to the FDA.
FDA officials are advising physicians not to prescribe long-term azithromycin in this population. Patients who have had a stem cell transplant and are already taking the antibiotic, should consult a doctor before discontinuing.
The manufacturer of brand name azithromycin (Zithromax) has issued a Dear Healthcare Provider letter about the safety issue, and more information can be found in the FDA’s safety announcement.
The Food and Drug Administration has issued a in patients with blood or lymph node cancers who have received donor stem cell transplants.
This use of azithromycin can lead to increased risk of cancer relapse and death in this population. The FDA is continuing to review data and is expected to issue further recommendations.
Patients with blood or lymph node cancers are at an increased risk of bronchiolitis obliterans syndrome after donor stem cell transplant; although azithromycin is not approved for prevention of this condition, the antibiotic is sometimes prescribed for that purpose.
A French study of 480 patients was undertaken to assess the effectiveness of this prophylaxis but revealed the increased risk of relapse and death and was halted 13 months after completing enrollment. The rate of cancer relapse was 32.9% in the azithromycin group and just 20.8% in the placebo group; the 2-year survival rate was 56.6% in the azithromycin group and 70.1% in the placebo group (JAMA 2017;318[6]:557-66).
Bronchiolitis obliterans syndrome is marked by inflammation and scarring of the airways that leads to severe shortness of breath and dry cough. There are no known effective antibiotic treatments for prophylaxis of the condition, according to the FDA.
FDA officials are advising physicians not to prescribe long-term azithromycin in this population. Patients who have had a stem cell transplant and are already taking the antibiotic, should consult a doctor before discontinuing.
The manufacturer of brand name azithromycin (Zithromax) has issued a Dear Healthcare Provider letter about the safety issue, and more information can be found in the FDA’s safety announcement.
The Food and Drug Administration has issued a in patients with blood or lymph node cancers who have received donor stem cell transplants.
This use of azithromycin can lead to increased risk of cancer relapse and death in this population. The FDA is continuing to review data and is expected to issue further recommendations.
Patients with blood or lymph node cancers are at an increased risk of bronchiolitis obliterans syndrome after donor stem cell transplant; although azithromycin is not approved for prevention of this condition, the antibiotic is sometimes prescribed for that purpose.
A French study of 480 patients was undertaken to assess the effectiveness of this prophylaxis but revealed the increased risk of relapse and death and was halted 13 months after completing enrollment. The rate of cancer relapse was 32.9% in the azithromycin group and just 20.8% in the placebo group; the 2-year survival rate was 56.6% in the azithromycin group and 70.1% in the placebo group (JAMA 2017;318[6]:557-66).
Bronchiolitis obliterans syndrome is marked by inflammation and scarring of the airways that leads to severe shortness of breath and dry cough. There are no known effective antibiotic treatments for prophylaxis of the condition, according to the FDA.
FDA officials are advising physicians not to prescribe long-term azithromycin in this population. Patients who have had a stem cell transplant and are already taking the antibiotic, should consult a doctor before discontinuing.
The manufacturer of brand name azithromycin (Zithromax) has issued a Dear Healthcare Provider letter about the safety issue, and more information can be found in the FDA’s safety announcement.