Currently, invasive aspergillosis (IA) is an important cause of morbidity and mortality of hospitalised patients of developing countries, though the exact frequency of IA is not known due to lack of adequate diagnostic mycology laboratories in such countries. Most clinicians are still unaware of the manifestations of IA. Only handful of centres from India, China, Thailand, Malaysia, Korea, Iran, Israel, Saudi Arabia, Sri Lanka, Egypt, Brazil, and Argentina have reported case series in the field of IA. The estimated number of IA is expected to be higher in developing countries compared to developed world due to below optimum hospital care practice, continuous hospital renovation work in the vicinity of wards occupied by immunocompromised patients, overuse or misuse of steroids by doctors and quacks (untrained health professionals), use of contaminated infusion sets/fluid, and increase in intravenous drug abusers. This is reflected by higher rate (6.1-90%) of IA in so-called immunocompetent hosts. Higher Aspergillus spore count in the hot and humid climate in developing countries (exceeding 12 X 106 / m3) is an additional risk factor for development of IA. Liver failure (33 cases at our centre), chronic obstructive pulmonary diseases (7.5%-94%), diabetes (2-17%), and tuberculosis (0-28%) are the new underlying diseases recognized for the development of IA. As tuberculosis patients are very high in number in developing countries, Aspergillus species get an opportunity to colonize tuberculous cavity and lead to IA in opportune moment. Even for patients with allergic bronchopulmonary aspergillosis, progression of disease to IA is reported. The clinical manifestations of IA have also certain peculiarities in developing countries. Besides usual invasive pulmonary aspergillosis, large numbers of cases of central nervous system (CNS) aspergillosis, and Aspergillus endophthalmitis are reported. CNS aspergillosis cases are largely due to extension of lesion from invasive fungal sinusitis. To diagnose the IA cases, the laboratories still rely considerably on conventional technique including direct microscopy, and culture. Galactomannan, β -D glucan test, and DNA detection in IA are available only in few centres. Though the use of HRCT has become popular in many centres, still a large numbers of IA cases are diagnosed only post-mortem. Interestingly the comparative rate of Aspergillus flavus infection is high (up to 56%) in developing countries. It may be due to higher prevalence of A. flavus in the environment. Antifungal use is largely restricted to amphotericin B deoxycholate and itraconazole, though voriconazole, caspofungin, and lipid preparations of amphotericin B are available in the market. This is due to prohibitive cost of latter group of antifungal drugs in developing countries.
Full conference title:
4th Advances Against Aspergillosis
- AAA 4th (2010)