Effect of a 150 mg dose of rifabutin on serum itraconazole levels in patients with coexisting chronic pulmonary aspergillosis and Mycobacterium avium complex lung disease

Simultaneous diagnosis of allergic bronchopulmonary aspergillosis and Mycobacterium avium complex lung disease

Allergic bronchopulmonary aspergillosis (ABPA) and Mycobacterium avium complex lung disease (MAC-LD) often coexist because bronchiectasis, caused by ABPA or MAC, might be an important predisposing factor for both conditions. Here, we describe a man with asthma symptoms who had centrilobular small nodules and mucoid impaction on chest CT. We diagnosed the patient with simultaneous ABPA and MAC-LD on the basis of bronchoscopy findings. Itraconazole monotherapy led to substantial clinical improvement, avoiding the adverse effects of systemic corticosteroids. Sputum culture conversion of MAC was achieved after switching from itraconazole monotherapy to combination therapy comprising clarithromycin, rifampicin and ethambutol. ABPA recurred but was controlled by reinitiation of itraconazole. Overall, corticosteroid management was avoided for 38 months. Itraconazole monotherapy may be selected as initial treatment for ABPA with chronic infection, including MAC.

Antifungal Drugs TDM: Trends and Update

PURPOSE

The increasing burden of invasive fungal infections results in growing challenges to antifungal (AF) therapeutic drug monitoring (TDM). This review aims to provide an overview of recent advances in AF TDM.

METHODS

We conducted a PubMed search for articles during 2016-2020 using "TDM" or "pharmacokinetics" or "drug-drug-interaction" with "antifungal," consolidated for each AF. Selection was limited to English language articles with human data on drug exposure.

RESULTS

More than 1000 articles matched the search terms. We selected 566 publications. The latest findings tend to confirm previous observations in real-life clinical settings. The pharmacokinetic variability related to special populations is not specific but must be considered. AF benefit-to-risk ratio, drug-drug interaction (DDI) profiles, and minimal inhibitory concentrations for pathogens must be known to manage at-risk situations and patients. Itraconazole has replaced ketoconazole in healthy volunteers DDI studies. Physiologically based pharmacokinetic modeling is widely used to assess metabolic azole DDI. AF prophylactic use was studied more for Aspergillus spp. and Mucorales in oncohematology and solid organ transplantation than for Candida (already studied). Emergence of central nervous system infection and severe infections in immunocompetent individuals both merit special attention. TDM is more challenging for azoles than amphotericin B and echinocandins. Fewer TDM requirements exist for fluconazole and isavuconazole (ISZ); however, ISZ is frequently used in clinical situations in which TDM is recommended. Voriconazole remains the most challenging of the AF, with toxicity limiting high-dose treatments. Moreover, alternative treatments (posaconazole tablets, ISZ) are now available.

CONCLUSIONS

TDM seems to be crucial for curative and/or long-term maintenance treatment in highly variable patients. TDM poses fewer cost issues than the drugs themselves or subsequent treatment issues. The integration of clinical pharmacology into multidisciplinary management is now increasingly seen as a part of patient care.

Treatment with a macrolide-containing regimen for Mycobacterium kansasii pulmonary disease

BACKGROUND

Mycobacterium kansasii is a major pathogen associated with nontuberculous mycobacterial pulmonary disease. For treatment of M. kansasii pulmonary disease, daily therapy with isoniazid, rifampin, and ethambutol is traditionally recommended. Although a regimen containing a macrolide, instead of isoniazid, has been recently recommended, supporting data are limited. We compared the treatment outcomes of a macrolide-containing regimen (macrolide group) and an isoniazid-containing regimen (isoniazid group) on patients with M. kansasii pulmonary disease.

METHODS

A total of 49 patients were identified between January 2002 and December 2016. Treatment outcomes for the isoniazid group (n = 24) and the macrolide group (n = 25) were compared.

RESULTS

Baseline characteristics of the isoniazid and macrolide groups were similar. Favorable outcomes did not differ between the isoniazid group (79%, n = 19) and macrolide group (88%, n = 22, P = 0.463). Total treatment duration (median 17.9 months vs. 15.4 months; P = 0.712) and time to culture conversion (median 2.0 months vs. 1.2 months; P = 0.838) were also similar between the isoniazid and macrolide groups. Five patients who completed three-times-weekly intermittent treatment containing a macrolide for non-cavitary M. kansasii pulmonary disease achieved negative sputum culture conversion within 12 months of treatment. Only one patient experienced recurrence of M. kansasii pulmonary disease in the isoniazid group.

CONCLUSIONS

A macrolide-containing regimen appears to be as effective as an isoniazid-containing regimen for treatment of M. kansasii pulmonary disease. Additionally, intermittent therapy containing a macrolide could be an alternative treatment option for non-cavitary M. kansasii pulmonary disease.

Risk factors for the development of chronic pulmonary aspergillosis in patients with nontuberculous mycobacterial lung disease

Nontuberculous mycobacterial lung disease (NTM-LD) is increasingly recognized as an important predisposing condition for the development of chronic pulmonary aspergillosis (CPA), but there are limited data on the risk factors for CPA development in NTM-LD patients. We reviewed the medical records of 566 patients who, at the time of diagnosis of NTM-LD, did not have CPA and who received ≥12 months of treatment for NTM-LD between January 2010 and June 2015. Of these patients, 41 (7.2%) developed CPA (NTM-CPA group), whereas the remaining 525 patients did not develop CPA (NTM group). The median time to the development of CPA was 18.0 months from treatment initiation for NTM-LD. The NTM-CPA group was older and had significantly higher proportions of males, current smokers, and patients with a low body mass index (<18.5 kg/m2), when compared to the NTM group. Moreover, the NTM-CPA group was more likely to have a history of tuberculosis and chronic obstructive lung disease and to have used inhaled or systemic steroids. In the NTM-CPA group, more than 40% of patients had Mycobacterium abscessus complex (MABC) as the cause of NTM-LD, and the fibrocavitary form of NTM-LD was the most common; both associations were higher than in the NTM group. Overall, 17 (3%) patients died, and the NTM-CPA group had a higher mortality rate than did the NTM group (19.5% vs. 1.7%, respectively; P<0.001). In a multivariable analysis, old age, male gender, low body mass index, chronic obstructive lung disease, systemic steroids, MABC as the etiologic organism, and the fibrocavitary form of NTM-LD remained significant predictors of development of CPA. In conclusion, CPA occurred in 7.2% of patients after initiation of treatment for NTM-LD, and some risk factors were associated with CPA development. Given the worse prognosis, early diagnosis and treatment of CPA are important in patients with NTM-LD.