Case Report Pyrenochaeta romeroi: a causative agent of phaeohyphomycotic cyst Ziauddin Khan, 1 Suhail Ahmad, 1 Kusum Kapila, 2 Noorni V. Ramaswamy, 3 Preetha Alath, 4 Leena Joseph 1 and Rachel Chandy 1 Correspondence Ziauddin Khan zkhan@hsc.edu.kw Received 23 December 2010 Accepted 20 February 2011 1 Department of Microbiology, Faculty of Medicine, Kuwait University, Kuwait 2 Department of Pathology, Faculty of Medicine, Kuwait University, Kuwait 3 Department of Haematology, Kuwait Cancer Control Center, Kuwait 4 Department of Cytology, Kuwait Cancer Control Center, Kuwait A subcutaneous phaeohyphomycotic cyst caused by Pyrenochaeta romeroi in a 47-year-old Indian female is described. The organism was isolated repeatedly from the aspirated material from the cyst. It was identified by colony and microscopic characteristics, and sequencing of internal transcribed spacer regions of the rDNA. Although the patient recovered without antifungal therapy, the isolate appeared resistant to commonly used antifungal agents. To the best of our knowledge, this is only the second report of subcutaneous phaeohyphomycotic cyst caused by Pyrenochaeta romeroi. Introduction The members of the genus Pyrenochaeta are widely distributed in the environment in soil or in association with wood and plant debris (de Hoog et al., 2000; Badali et al., 2010). So far, four species, namely Pyrenochaeta romeroi, Pyrenochaeta mackinnonii, Pyrenochaeta unguis-hominis and Pyrenochaeta keratinophila, have been implicated in human infections (de Hoog et al., 2000; Ferrer et al., 2009; Badali et al., 2010; Verkley et al., 2010). Previously, Pyrenochaeta unguis-hominis has been isolated from cases of onychomy- cosis (English, 1980). However, the aetiological role of this species in nail infection has not been established unequi- vocally (Punithalingam, 1979). Most of the isolates of Pyrenochaeta romeroi and Pyrenochaeta mackinnonii have originated from clinical material obtained from patients with mycetoma (Andre ´ et al., 1968; Baylet et al., 1968; David-Chausse ´ et al., 1968; Young et al., 1973; Thammayya et al., 1979; Cerar et al., 2009). The lesions usually develop slowly following trauma and remain localized to cutaneous and subcutaneous tissues (Borelli, 1979; Serrano et al., 1998; Girard et al., 2004). Apart from the aetiological role of Pyrenochaeta romeroi in black grain mycetoma, the species has recently been isolated from a case of subcutaneous phaeohyphomycotic cyst in an Indian female, thus increas- ing the spectrum of its clinical manifestations (Badali et al., 2010). Here, we present a second case of subcutaneous phaeohyphomycotic cyst caused by Pyrenochaeta romeroi in an Indian female with acute lymphoblastic leukaemia (ALL). Case report A 47-year-old Indian female with ALL, a resident of Kuwait since September 2006, was diagnosed with ALL in September 2006 and completed a hyper-CVAD (cyclophosphamide, vincristine, Adriamycin, dexona, a high dose of methotrexate and a high dose of cytosine arabinoside) regimen in May 2007. In June 2007, she was started on maintenance therapy comprising prednisone, vincristine, methotrexate and 6- mercaptopurine. During her regular follow-up, she noticed a small round swelling over the proximal interphalangeal joint of the right index finger in July 2009. This lesion developed gradually over a 6-month period and remained localized with no discharge or sinus formation (Fig. 1). It was painless and attained a diameter of about 10 mm with central necrosis. The patient gave no history of trauma at the site of infection. She had not visited her home country since 2006. The pus from the cystic lesion was aspirated. It was non-sanguineous and free from any discrete granules. Microscopic examina- tion of the aspirated material with 10 % KOH–calcofluor and of smears stained with Gomori methenamine–silver revealed septate hyphal elements with irregular swellings (Fig. 2a, b). Haematoxylin and eosin-stained smears also showed fungal elements along with an acute inflammatory response containing a few epitheloid granulomas and multi- nucleated giant cells. No antifungal therapy was adminis- tered. Following repeated drainage of the exudates, the swelling subsided gradually over a 2-month period. Abbreviation: ALL, acute lymphoblastic leukaemia. The GenBank/EMBL/DDBJ accession number for the sequence of the ITS region of the Pyrenochaeta romeroi isolate from this study is FN826905. Journal of Medical Microbiology (2011), 60, 842–846 DOI 10.1099/jmm.0.029520-0 842 029520 G 2011 SGM Printed in Great Britain