Page mackup April-14.qxd Bangladesh Journal of Medical Science Vol. 13 No. 02 April’14 228 Case Report A Rare case of Subcutaneous Mycosis due to Rhizoctonia solani Sahu. S1, Padhy .S2, Dash.M3, Mohanty.I4, Pattnaik.S5 Introduction: Rhizoctonia solani (R.solani) is the most common- ly identified species of Rhizoctonia. It is a soil borne pathogen with a great diversity of host plants. It was described by Julius Kuhn on potato in 1858.It is a basidiomycete fungus that does not produce any asexual spores. In nature, it reproduces asexually and exists primarily as vegetative mycelium and/or sclerotia1.The vegetative mycelium of Rhizoctonia solani are colorless when young but become brown colored as they grow and mature.The key to identify R.solani are characteristics of its septate hyphae branching at 90? angles ,constrictions at the base of the hyphal branching sometimes with anastomosis and clear white , darkbrown to black colored colonies on SDA. It can be able to survive for extended periods of time in the absence of living host plants by feeding on decaying organic mat- ter2.To the best of our knowledge this is the first ever case of human subcutaneous mycosis due to Rhizoctonia solani reported from south odisha. Case report: A 52 year old female agricultural worker by profes- sion came with a complaint of progressive swelling over the upper part of left leg for the past 3 months .It is a single circular swelling of size 6x5 cm pres- ent on the anterior part of the left leg extends up to lower border of patella . It extended medial and lat- eral compartments slightly.Skin over the swelling was normal without any inflammatory signs.No vis- ible veins,pulsations ,sinus or any discharge from the swelling were seen .On palpation there was no local rise of temperature ,no tenderness and skin over the swelling was pinchable. All the borders were well defined and it was soft in consistency. There was no restricted joint mobility. There was a history of trauma while working in the paddy field.On general examination all the vitals were normal. She had mild pallor.The patient was diabetic but not hypertensive. Pus was aspitated under aseptic conditions and sent to the department Correspond to: Dr.Susmita Sahu, Department of Microbiology M.K.C.G Medical college, Berhampur Odisha PIN- 760001 e-mail: susmitakumarisahu@gmail.com Abstract: Rhizoctonia solani is a very common soil borne pathogen with a great diversity of host plants. A 52 year old lady presented with sole manifestation of subcutaneous swelling over the left leg for 3 months Pus was collected by aspiration revealed septatate fungal hyphae. After culture on SDA at 25 C showed white cottony growth initially, progressed to buff colored to black colonies on further incubation. On LPCB mount we found septate hyphae with acute and right angled branching with out any conidia and hyphal anastomosis which resembled features of Rhizoctonia solani. Patient was put on Fluconazole and responded well to the treatment. 1. Sahu. S, Senior resident, M.K.C.G Medical college 2. Padhy .S, Assistant professor, M.K.C.G Medical college 3. Dash.M , Assistant professor, M.K.C.G Medical college 4. Mohanty.I , Senior resident, M.K.C.G Medical college 5. Pattnaik.S, Junior resident, M.K.C.G Medical college Department of Microbiology; M.K.C.G Medical college Berhampur, Odisha, India. DOI: http://dx.doi.org/10.3329/bjms.v13i2.15060 Bangladesh Journal of Medical Science Vol.13(2) 2014 p.228-230 of microbiology for examination. It was thick and brown in colour without any odour on gross exami- nation .Gram stain of the pus revealed few number of pus cells with septate hyphae. Basing on the pre- liminary staining report pus sample was inoculated into SDA (Sabourauds dextrose agar) slants incubat- ed at 25?C and 37?C . After 5 days of incubation at 25?C cottony white growth was appeared which later turned tan to black colored starting from the periphery of the media. On further incubation.The whole colony turned dark black coloured .The reverse side showed white to grey colour LPCB mount of the colony showed septate hyphae without conidia.The hyphae showed right angled branching hyphae at some places fused together to form anas- tomosis .This was identified as Rhizoctonia solani basing on above features.Patient was put on oral Fluconazole and the whole pus was drained. The patient was discharged with advice for follow up in out patient department. Discussion: Rhizoctonia solani belongs to the Phylum Basidiomycota,class Agaricomycetes, order Cantharellales,Family ceratobasidiaceae and genus Rhizoctonia2 .It usually exists in nature as vegetative mycelium and does not produce any asexual spores. It consists of hyphae partitioned into individual cells by septum containing small pore through which movement of cytoplasm, mitochondria and nuclei from cell to cell occurs.The hyphae branch often branch at a 900 angles and usually possess more than three nuclei per hyphal cells. The branched hyphae is sometimes slightly constricted at the origin.They produce sclerotia which are resistant to variation in environmental conditions. These above features dif- ferentiate R.solani from other Rhizoctonia fungi. R.solani grows on potato dextrose agar and forms grey to black colored colonies at the temperature range of 18-280 .Sclerotia are produced on the sur- face of cultures after 4 to 6 six weeks of incubation2. In 1969, J.R Parmeter and his colleagues reintro- duced the concept of ‘hyphal anastomosis’ to charac- terize and identify Rhizoctonia.This includes that the isolates of Rhizoctonia which have the ability to rec- ognize and fuse with each other are genetically relat- ed,where as isolates that do not have this ability are genetically unrelated3,4.This hyphal anastomosis cri- teria have been extensively used to place isolates of Rhizoctonia into taxonomically distinct groups .It is grouped into 13 anastomosis groups (AG) that vary in pathogenecity,physical characsteristics and sequence variations5. It is the method of genetic recombination in Rhizoctonia. It causes wide range of commercially significant plant diseases ,but reports of human diseases caused by it are very rare6. Till now two cases of human mycosis due Rhizoctonium solani causing Keratitis7 and extensive mycosis2 were reported. In this case the patient was a agricultural field work- er and gave the history of trauma while working in the field.This might be the cause of infection by pen- etration of soil pathogen through the injury.Also the patient is a known diabetic which helped the pathogen to grow at the site of injury. To conclude ,R.solani is a well known plant pathogen and very rarely causes human infection.This case was report- ed because of its rarity. Figure-1: Subcutaneous swelling on left leg. Figure-2: Gram staining of pus sample showed septate branched hyphae Subcutaneous Mycosis due to Rhizoctonia solani 229 Reference: 1. Paulo ceresini Pathogen profile created by course PP- 728 Soil borne plant pathogens,offered on spring1999 2. Kaore NM,Atul AR,Khan MZ,Ramnani VK. A rare case of human mycosis by Rhizoctonia solani.Indian J Med Microbiol 2012; 30:361-3. http://dx.doi.org/10.4103/0255-0857.99508 3. Anderson NA.The Genetics and Pathology of Rhizoctonia Solani. Annu Rev Phytopathol 1982; 20:329-47. http://dx.doi.org/10.1146/annurev.py.20.090182.001553 4. Gracia VG,Onco MAP,Susan VR.Review,Biology and Systematics of the form genus Rhizoctonia.Span J Agric Res 2006;4:55-79. 5. Foley RC,Gleason CA,Anderson JP,Hamann T,Singh KB(2013). Genetic and Genomic analysis of Rhizoctonia solani Interactions with Arabidopsis;Evidence of Resistance mediated through NADPH oxidases.PLOSONE 8(2):e56814 doi :10.137/journal.pone.0056814. 6. Manisha K,Panwar N.Morphological effects of Isolated fungal specis on Human p o p u l a t i o n . 1 : 5 2 1 . d o i : 1 0 . 4 1 7 2 / S c i e n t i f i c reports.521.2012;1:1-6. 7. Srivastava OP,Lal B,Agarwal PK,Agarwal SC,Chandra B,Mathur IS.Myotic keratitis due to Rhizoctonia sp.Sabouraudia 1977;15:125-31. http://dx.doi.org/10.1080/00362177785190201 Sahu. S, Padhy .S, Dash.M, Mohanty.I, Pattnaik.S 230 Figure-3: Growth of Rhizoctonia after 12 days on SDA agar. Figure-3: Fig 4 LPCB mount from slide culture showing right anglebranching and anastomosis