Author:
DW Denning1,2*
Author address:
1Manchester Fungal Infection Group, The University of Manchester, Manchester , UK
2Director’s Office, Global Action For Fungal Infections, Geneva, Switzerland
Full conference title:
10th Advances Against Aspergillosis and Mucormycosis
Date: 2 February 2022
Abstract:
Purpose:
Chronic pulmonary aspergillosis (CPA) may be confused with, be a co-infection of pulmonary tuberculosis (PTB), or manifest after completion of anti-tuberculous therapy (ATT). In 2011, we modeled its occurrence after ATT, primarily using data from a UK longitudinal study of 500 patients. Since then, much additional data has been published allowing more sophisticated modeling.
Methods:
Epidemiological literature on CPA has been continuously tracked since 2010. Papers with high quality datasets were selected for modeling purposes.
Results:
Key assumptions made are
· The percentage of clinically diagnosed ‘PTB’ patients with CPA is 20% in HIV- and 10% in HIV+ (Nigeria: Oladele, 2017).
· The percentage of patients with CPA and PTB or developing it as ATT finishes, presenting in the first years after PTB diagnosis is 10% (Indonesia: Setianingrum, 2021).
· The percentage of cured PTB patients left with cavitation is 12% in Europe, 22% outside Europe, or higher if documented in that country (multiple studies).
· The annual rate of development of CPA from 2-5 years after PTB diagnosis is 6.5% in those with cavitation and 0.2% in those without (Uganda: Page, 2018).
· The mortality of CPA is 20% in year 1 and 10% thereafter (Japan: Ohba, 2011; France: Maitre, 2021).
These assumptions (which are supported more broadly in other papers) can be used to estimate the annual incidence of CPA, annual deaths from CPA and 5 year period prevalence.
As one example, Agarwal et al in 2014 estimated a 5 year period prevalence of CPA in India of 290,147 cases, all PTB related. The new model provides an annual incidence estimate of 328,049 cases, a prevalence of 1,310,000 and annual deaths of 197,494 in the context of 2,072,000 PTB cases, 54% of which are proven, not including non-TB cases. A recent publication from Vietnam found that 57% of TB patients returning to care with symptoms after completion of ATT had CPA (Singla, 2021).
Conclusion:
The diagnosis of CPA can be difficult and with Aspergillus antibody testing very difficult in its early phases. Modelling provides a guide to the size of the problem in each country. As George Box said: “Essentially all models are wrong, but some are useful.”
Abstract Number: 1
Conference Poster: Poster 001
Conference Year: 2022
URL Conference abstract: