INTRODUCTION:When the host’s defenses are altered, aspergillus can lead to several clinical conditions, such as hypersensitivity or allergic reactions. These reactions can mimic infections, or obstructive pulmonary diseases, such as asthma.
CASE PRESENTATION:A 25-year-old non- smoking African American female presented with dyspnea and chronic cough of five months’ duration. The cough was productive of thick, whitish ‘rock- like’ masses, associated with mild shortness of breath on exertion and low-grade fevers. She denied weight loss, night sweats and hemoptysis. There was no history of occupational exposure or allergies. On exam, she was afebrile, saturating 98% on room air and had mild distress with prolonged speaking. The patient had a normal WBC count with the exception of a slightly elevated absolute eosinophil count (7,500/dl).Initially, she was treated for ‘asthma’ as an outpatient with an albuterol inhaler. A chest x-ray (CXR) was ordered for continued symptoms, which revealed an infiltrate. Despite multiple courses of antibiotics, over the next 3 months her symptoms persisted during which time repeated CXR’s showed progression of the infiltrates. The following diagnoses were entertained: resistant bacteria, atypical organisms, noninfectious entities, such as cryptogenic organizing pneumonia. At this point, antibiotics were withheld since findings were not consistent with an acute infection. A fungal hypersensitivity panel (serum precipitans to various Aspergillus species, IgE levels, and eosinophil levels) was negative. A chest CT showed an area of consolidation and multiple ovoid densities with distal tapering ends in bilateral lower lobes. The densities were of low attenuation and seen to fill and expand the airways. Bronchoscopy was performed and showed multiple whitish plugs obstructing the endobronchial lumens. On pathology, the plugs contained Aspergillus hyphae, mucus/fibrin, eosinophils, necrotic debris and Charcot-Leyden crystals. There was no invasion of the mucosa by Aspergillus. She was started on prednisone 80 mg/day and discharged. Within two weeks her exertional dyspnea had improved dramatically. Steroids were tapered over the following few months. By five months, the patient had complete resolution of symptoms, with minimal residual radiological findings.
DISCUSSIONS: The patient’s clinical, laboratory and radiological findings did not fulfill the Patterson criteria for allergic bronchopulmonary mycosis (ABPM), nor the pathological criteria for bronchocentric granulomatosis and plasitic bronchitis. Instead, her findings were most consistent with the diagnosis of Mucoid Impaction Syndrome (MIS). In MIS, there is no predilection for age or sex. Patients can present with nonspecific respiratory symptoms, recurrent infections, and expectoration of cast-like mucoid plugs. Although the pathophysiology is still unclear, the plugs are thought to occur as a result of hypersensitivity to fungus which causes overproduction of mucus. Serological findings may include peripheral eosinophilia, and pathology may occasionally demonstrate fungal hyphae. Radiographic findings showing characteristic ‘cluster of grapes’, or ‘finger- in- glove’ appearance represent the mucus plugs impacting and dilating the airways. Good clinical response is seen to prolonged steroids of 4- 6 months duration, and concomitant antifungals are only required in refractory or invasive disease. In rare situations, prolonged mucus impaction can give rise to complications requiring surgical treatment.
CONCLUSION:MIS should be differentiated from other hypersensitivity reactions to Aspergillus such as ABPM, plastic bronchitis and bronchocentric granulomatosis, which can have similar presentations. If additional fungal hypersensitivity is well documented, the syndrome should be called ABPM rather than MIS. At times, the physical symptoms can precede the radiographic abnormalities as in our patient, and bronchoscopy becomes the only definitive way to uncover endobronchial involvement. Mucoid impaction syndrome should be suspected in patients with symptoms of dyspnea and recurrent infection, a negative fungal hypersensitivity panel, and expectoration of cast- like mucus plugs with characteristic radiographic findings of impacted and dilated bronchi.
DISCLOSURE:Neelam Patel, No Financial Disclosure Information; No Product/Research Disclosure Information