Introduction
Pulmonary aspergillosis remains a significant cause of morbidity and mortality in immunocompromised patients. 1 Timely and accurate diagnosis is essential but remains challenging because of non-specific clinical and radiological findings. An important impediment for timely diagnosis is the low yield of positive cultures from respiratory specimens. Furthermore, the positive cultures may not always be indicative of Aspergillus infection. Among the newly delineated species of Aspergillus, A. terreus is associated with severe life-threatening infections. 2 We report a case of pulmonary aspergillosis due to A.terreus in a patient of chronic obstructive pulmonary disease.
Case Report
A 68-year-old diabetic and hypertensive female with chronic obstructive pulmonary disease was admitted in Intensive care unit with chief complaints of breathlessness and high grade fever. On diagnostic evaluation patient had high TLC (15,000/cu.mm) & deranged pulmonary function tests. On repeated endotracheal aspiration for bacterial culture sensitivity, polymicrobial microorganisms isolated. The bacterial isolates (Pseudomonas aeruginosa, Klebsiella pneumoniae, etc) were sensitive to carbapenem group of drugs and colistin. However, there was no improvement in patient’s condition. She was then prepared for collection of bronchoalveolar lavage. Thereafter, three BAL samples at an interval of 3 days were sent for evaluation of fungal etiology. After 5-7 days of aerobic incubation at 37 ̊C on Sabouraud dextrose agar (SDA), there was significant growth of mold. On the obverse mycelium growth was white to pale yellow, dense and in tufts. Conidia tan to light brown with a powdery texture which turned the media bright yellow (Figure 1a). Reverse was reddish brown in appearance. The Lacto Phenol Cotton Blue (LPCB) mount was prepared which showed compact, columnar and biseriate conidial head of size approximately 30 to 50 μm in diameter. Conidiophores were hyaline and smooth walled; conidia were globose shaped, smooth walled and 1.5 to 2.5 μm in diameter (Figure 1b). There was presence of similar growth on 2ndand 3rd bronchoalveolar lavage samples from the patient. Patient was initially managed onthe clinical suspicion of pulmonary mycosis using Amphotericin B but as soon clinicians were informed about A. terreus infection and its inherent resistance to Amphotericin B, the antifungal treatment was changed to Voriconazole 200mg BD for 3 weeks. Other supportive measures were continued with antimicrobials coverage. Repeat BAL culture after 3 weeks of voriconazole treatment was negative for aspergillosis. Gradually improvement in patient’scondition was observed and she was discharged without any adverse events.
Discussion
The spores of Aspergillus species are present ubiquitously in environment, and the risk of spread of infection is influenced by living conditions like precipitation patterns, humidity, temperature, and wind conditions.1 The patients’ immune status plays a major role in contracting infection due to Aspergillus species. Aspergillus spp cause diseases like allergic bronchial pulmonary Aspergillosis (ABPA), aspergilloma, chronic necrotizing Aspergillus pneumonia, and invasive diseases.3 Aspergillus terreus complex belong to section Terrei in which Aspergillus terreus sensustricto is the most commonly isolated species with other species in the complex A. alabamensis, A. allahabadii, A. ambiguus, A. aureoterreus, A. bicephalus, A. carneus, A. citrinoterreus, A. floccosus, A. iranicus, A. hortai, A. microcysticus, A. neoafricanus, A. neoindicus, A. niveus, and A. pseudoterreus. 3 There have been reports of Aspergillus terreus causing invasive infections like fungal peritonitis, fungal spondylodiscitis, fungal sinusitis as well as cutaneous fungal infections.4, 5 The case presented here also was immunosuppressed due to her diabetic as well as hypertensive state. There was no improvement in patients’ status instead of getting treatment for bacterial growth in bronchoalveolar lavage which indicated that there was some other underlying cause which ultimately grew as Aspergillus terreus on fungal culture. Keeping the differential diagnosis of fungal etiology in such immunosuppressed patients would help in better treatment of patients presenting with such symptoms.
Triazoles like voriconazole, isavuconazole and lipid formulation of Amphotericin B are the mainstay of Aspergillus treatment but Aspergillus terreus are found to be resistant to polyenes hence in case of Amphotericin B being treatment option, the speciation of Aspergillus is necessary so the wrong treatment could be avoided. 6, 7 In vitro susceptibility testing may be a predictor of clinical outcome of invasive aspergillosis, although this has not yet been firmly established; this would be particularly important for infections with A. terreus, given its resistance to amphotericin B. The patient in our case also improved when the Amphotericin B was switched with Voriconazole thus indicating the importance of proper identification of invasive molds till species level.
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