A 61-year-old female who had never smoked was referred to Osaka University Hospital with a productive cough, shortness of breath, and wheezing for 5 years. She had a high eosinophil range of 6–20% (normal, 2–4%) and transient recurrent infiltrates on serial chest X-rays. Eosinophilic pneumonia with bronchial asthma had been diagnosed and treatment with oral prednisolone resulted in the remission of symptoms for 2–3 weeks at a time.\nThe patient complained of up to 10 mL of sputum per day which was purulent, malodorous and sometimes formed mucoid plugs. She was prescribed with inhaled corticosteroids and long-acting beta-agonists. She was found to have bilateral coarse crepitations with biphasic polyphonic rhonchi on pulmonary examination. Blood cell analysis revealed a total leukocyte count of 7240 cells/μL; with 44.7% polymorphs, 36.8% lymphocytes, 5.5% monocytes, 11.9% eosinophils, and 1.1% basophils. The absolute eosinophil count was elevated at 861/μL. Serum biochemistry findings were unremarkable, and Aspergillus spp. IgG antibody was negative. Total IgE was within the normal range (70.36 IU/mL), but specific IgE for Aspergillus spp. was found to be positive.\nA chest X-ray showed infiltrates in the right lower lung (A), and computed tomography revealed bilateral dilation of the central bronchi in the right upper lobe (B). The involved bronchi contained hyperattenuating mucus. Bilateral central bronchiectasis was diagnosed. The patient was further investigated because saccular bronchiectasis is a feature of allergic bronchopulmonary aspergillosis (ABPA). Direct analysis of sputum samples using random sequencing (shotgun sequence) using a next-generation sequencer revealed fungal DNA. Aspergillus fumigatus was dominant and four other fungal sequences including Schizophyllum commune were found ().\nMicroscopic assessment of sputum was negative for acid-fast bacilli (AFB) and other bacteria. However, Charcot–Leyden crystals that are generated through the breakdown of eosinophils and hyphae were identified (C and D). Direct microscopy of KOH wet mounts of three consecutive sputum specimens and expectorated sputum/mucoid plugs revealed two types of septate and branching hyphae (A and B). Homogenized sputum and mucoid plugs inoculated onto Sabouraud's glucose agar (SGA) developed green and white colonies with a wooly texture after 4 days at 2 °C (C and D).\nOne of the fungi was morphologically identified as A. fumigatus (A and C), but the other (B and D) remained obscure. Therefore, DNA was extracted and the internal transcribed spacer region (ITS) and the D1/D2 region of large subunit rRNA gene were amplified by PCR. Direct sequencing of the PCR products showed that the sequences of the ITS and D1/D2 regions were 100% similar to those of various S. commune strains, such as IFM 46097. The diagnosis of allergic bronchopulmonary mycosis (ABPM) due to co-infection with A. fumigatus and S. commune was made.\nThe susceptibility of the isolated A. fumigatus and S. commune strains to antifungal drugs (minimum inhibitory concentration; MIC) was as follows: amphotericin B (1 and 0.5 μg/mL), 5-fluorocytosine (64 and 0.25 μg/mL), fluconazole (>64 and 4 μg/mL), itraconazole (0.12 and 0.25 μg/mL), voriconazole (0.5 and 0.12 μg/mL), and micofungin (0.03 and >16 μg/mL), respectively.\nThe administration of oral itraconazole and prednisolone, improved the symptoms in this patient.
A 54-year-old woman was referred to Saitama Cardiovascular and Respiratory Center in August 2000 for investigation of a cough, sputum, and an abnormal chest X-ray shadow. The cough and sputum had developed in December 1999 and had not improved. The patient had no relevant personal or family history. Physical examination did not reveal any abnormalities, including wheezes.\nChest X-ray showed bilateral, hilar band-like shadows (). Computed tomography (CT) of the chest showed mucous plugs in both B3 bronchi and consolidation (indicating atelectasis) in the peripheral part of the mucous plugs (). Pulmonary function tests did not indicate bronchial asthma. Laboratory tests showed a white blood cell count of 3,400/mm3, with 9.5 percent eosinophils (323/µl). Radioimmunosorbent test showed the IgE concentration to be within normal limits, and results of radioallergosorbent test for specific IgE antibodies against Aspergillus, Cladosporium, Candida, and Cryptococcus were all negative. No inflammatory reactions, assessed by the C-reactive protein level and erythrocyte sedimentation rate, were observed. Bronchoscopy disclosed thick white mucous plugs in both B3 bronchi () that could not be removed by forceps and suctioning. Removal was attempted again on another day but failed. Higher magnification of the mucous plug sample showed numerous eosinophils (). Grocott staining of the mucous plug sample showed mold with a fragmented appearance (). Transbronchial lung biopsy specimens showed infiltration of eosinophils in the wall of the right upper lobe bronchus. From the third to tenth day after cultivation, cultures of the mucous plugs, bronchial aspirates, and sputum samples yielded the same mycelial colonies, which were white and had a felt-like, fluffy appearance on Sabouraud dextrose agar plates (); however, no other pathogenic microorganisms were isolated. A methane-like odor was observed. With regard to form, there were narrow and thin walls approximately 1.5 mm in width, as well as wide and thick walls approximately 2.5 mm in width, with separate hyphae but no clamp connection. Considering the feature of colonies, form, odor, and the two types of hyphae in the colony, we hypothesized that it was a monokaryotic strain of S. commune. We consulted the Chiba University Research Center for Pathogenic Fungi and Microbial Toxicoses for identification of the fungus. Mating tests were performed [,,]. The clinical isolate was inoculated onto plates opposite each tester monokaryotic strain of S. commune, wherein it was dikaryotized and a fruit body was formed at the point of contact (). When co-cultured with a dikaryotic strain, it was dikaryotized and produced basidiocarps. From the foregoing, this fungus was identified as a monokaryotic mycelium of S. commune. At a later time, the presence of S. commune in the patient's garden was confirmed ().\nABPM, as well as ABPA (allergic bronchopulmonary aspergillosis), usually is diagnosed on the basis of Rosenberg’s seven primary criteria []: (1) episodic bronchial obstruction (asthma); (2) peripheral blood eosinophilia; (3) immediate scratch test reactivity to Aspergillus antigen; (4) precipitating antibodies to Aspergillus antigen; (5) elevated serum IgE concentrations; (6) history of pulmonary infiltrates (transient or fixed); and (7) central bronchiectasis. The diagnosis of ABPM is considered likely if the first six criteria were present, and the presence of all seven made the diagnosis certain. The present case satisfied only two (the second and the sixth criteria) of seven criteria (neither the third nor the fourth criteria were investigated because of methodological limitation), and diagnosis of ABPM cannot be established. We diagnosed the patient as MIB due to S. commune infection.\nComplete removal of the mucous plugs by bronchoscopy was attempted twice unsuccessfully, and the patient was treated with ITCZ for three months, beginning in September 2000. The cough improved and sputum diminished, and in December 2000, bronchoscopy disclosed that the mucous plugs had disappeared. Bronchoscopy was repeated in July 2001, January 2002, and 2003, and there has been no recurrence of the mucous plugs () or symptoms. The patient has been followed up on an outpatient basis for seven years and has shown no signs of recurrence.