BackgroundNontuberculous mycobacterial (NTM) pulmonary disease has conventionally been classified on the basis of radiology into fibrocavitary and nodular-bronchiectatic disease. Whilst being of great clinical utility, this may not capture the full spectrum of radiological appearances present. The aim of this study was to use latent class analysis (LCA) as an unbiased method of grouping subjects with NTM-pulmonary disease based on their CT features and to compare the clinical characteristics of these groups.MethodsIndividuals with NTM-pulmonary disease were recruited and a contemporaneous CT scan obtained. This was scored using an NTM-specific scoring system. LCA was used to identify groups with common radiological characteristics. The analysis was then repeated in an independent cohort.ResultsThree classes were identified in the initial cohort of 85 subjects. Group 1 was characterised by severe bronchiectasis, cavitation and aspergillomas, Group 2 by relatively minor radiological changes, and Group 3 by predominantly bronchiectasis only. These findings were reproduced in an independent cohort of 62 subjects. Subjects in Group 1 had a lower BMI and serum albumin, higher serum CRP, and a higher mortality.ConclusionsThese findings suggest that NTM-pulmonary may be divided into three radiological subgroups, and that important clinical and survival differences exist between these groups.Electronic supplementary materialThe online version of this article (10.1186/s12890-018-0675-8) contains supplementary material, which is available to authorized users.
Introduction Human rhinoviruses (HRV) are the main aetiological agents of virus-associated COPD exacerbations (Seemungal et al. AJRCCM 2001). The relationship between upper respiratory tract symptoms and HRV load at exacerbation presentation (ExP) and during recovery has not been described in naturallyoccurring exacerbations. We quantified changes in airway HRV load at ExP and during the recovery period, in patients reporting symptoms of a cold, sore throat, or both. Methods Patients in the London COPD cohort recorded new or increased respiratory symptoms on daily diary cards. Exacerbations were defined as an increase in respiratory symptoms for two consecutive days, with at least one symptom being major (dyspnoea, sputum purulence or volume) and the other a major or minor (wheeze, cold, sore throat, cough). Reverse-transcription quantitative PCR was used to detect and quantify HRV in 106 sputum samples collected at ExP (n = 38) and days 3 (n = 16), 7 (n = 27), 14 (n = 16), 35 (n = 6) and 56 (n = 3) following.Results HRV load decreased significantly from ExP to Day 3 in samples associated with either cold symptoms (p < 0.001) or sore throat (p = 0.049) but not in those associated with both symptoms (Figure 1). At Day 3 the HRV load in samples with both symptoms (n = 5) was significantly higher than in those with cold symptoms only (n = 9) (10 4.22(3.94-4.88) vs 10 0.55(0-1.98) pfu/ml; p = 0.002) but not for those with a sore throat only (n = 2) (10 0.89(0-0.89) pfu/ml; p = 0.095). At Day 7, the median (IQR) HRV load in samples with both symptoms (n = 4) (10 4.48(1.85-7.28) pfu/ml) was significantly higher than in those with cold symptoms only (n = 19) (10 0(0-2.74) pfu/ml; p = 0.018) or a sore throat only (n = 4) (10 0(0-0) pfu/ml; p = 0.029). There was no significant difference at subsequent time-points. Conclusion Patients reporting both cold symptoms and a sore throat as part of a COPD exacerbation had higher HRV loads than those with just one symptom until after Day 7 post-exacerbation. In patients with both symptoms, the HRV load remained higher for a longer period of time than in patients with only one symptom, which may suggest longer recovery times for more symptomatic patients. These results may inform the timing of administration of antiviral therapies at COPD exacerbation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.