Clinical Dermatology Review

CASE REPORT
Year
: 2020  |  Volume : 4  |  Issue : 2  |  Page : 182--185

Eumycetoma caused by Alternaria alternata in an immunocompetent host: A rare case report


Vasudha A Belgaumkar, Ravindranath Brahmadeo Chavan, Vijay Vidyadhar Raut, Pallavi Prataprao Patil 
 Department of Dermatology, Venereology and Leprology, BJ Government Medical College and Sassoon General Hospital, Pune, Maharashtra, India

Correspondence Address:
Ravindranath Brahmadeo Chavan
Department of Dermatology, Venereology and Leprology, BJ Government Medical College and Sassoon General Hospital, Pune - 411 001, Maharashtra
India

Abstract

Mycetoma is a chronic granulomatous subcutaneous infection caused by either true fungi (eumycetoma) or filamentous anaerobic bacteria (actinomycetoma). Herein, we report a case of mycetoma foot due to a rare opportunistic fungus in a male farmer. He presented with swelling and sinuses discharging pus and bloodstained black granules on the right foot for 6 years. A final diagnosis of eumycetoma (caused by Alternaria alternata) with bone involvement in immunocompetent patient was confirmed on the basis of histopathology and culture. Opportunistic fungi most commonly cause infection in immunocompromised hosts. Although mycetoma caused by opportunistic and saprophytic fungi responds relatively well to systemic antifungal treatment, few cases such as ours might require amputation. Clinically, it is difficult to comprehend the exact etiological agent. Proper diagnosis and radiological investigation are necessary for the precise identification of the etiological agent and extent of spread which in turn dictate choice of treatment.



How to cite this article:
Belgaumkar VA, Chavan RB, Raut VV, Patil PP. Eumycetoma caused by Alternaria alternata in an immunocompetent host: A rare case report.Clin Dermatol Rev 2020;4:182-185


How to cite this URL:
Belgaumkar VA, Chavan RB, Raut VV, Patil PP. Eumycetoma caused by Alternaria alternata in an immunocompetent host: A rare case report. Clin Dermatol Rev [serial online] 2020 [cited 2020 Oct 27 ];4:182-185
Available from: https://www.cdriadvlkn.org/text.asp?2020/4/2/182/292470


Full Text



 Introduction



Maduramycosis, most commonly known as “Madura foot,” is a localized chronic subcutaneous infection caused by various saprophytic species of fungi or anaerobic actinomycetes. Mycetoma is a triad comprising painless tumefaction, sinuses, and grains. It is most prevalent in males aged 11–30 years.[1] Most of the cases have been reported from Mexico, Sudan, and India. The most frequently isolated actinomycetes include Actinomadura madurae, Streptomyces somaliensis, Actinomadura pelletieri, Nocardia brasiliensis, and Nocardia asteroides, whereas the most common fungi are Madurella mycetomatis, Scedosporium Boydii, Falciformispora senegalensis, and Trematosphaeria grisea.[2] Herein, we report a case of fulminant eumycetoma caused by a rare opportunistic microorganism.

 Case Report



A 72-year-old male farmer, resident of a rural area in Pune district, Maharashtra, India, reported with a gradually increasing asymptomatic swelling on the right foot for 6 years, associated with intermittent fever, localized pain, and oozing of blood-stained pus for 1 year. History of discharge of black-colored material was elicited. He had been treated at various health centers with multiple courses of antibiotics without any improvement. The patient could not recall any injury preceding appearance of the swelling. He was not a known case of any systemic comorbidities.

On local examination, there was a bosselated swelling over the right foot with multiple nodules, discharging sinuses, and scars on mediolateral aspect. The overlying skin was hyperpigmented and indurated [Figure 1]a and [Figure 1]b. The discharge was purulent and hemorrhagic with extrusion of black-colored granules on overnight occlusion with gauze. General and systemic examination was normal. Clinical diagnosis of eumycetoma was considered. Investigations revealed low hemoglobin 8.9 mg/dL), and serum ferritin suggestive of anemia of chronic disease; all other investigations including HIV serostatus were unremarkable. Gram stain revealed Gram-positive cocci in groups, confirmed as methicillin-resistant Staphylococcus aureus sensitive to clindamycin on culture. X-ray of the right foot showed multiple osteolytic lesions with minimal adjacent sclerosis involving tarsals, metatarsals, and lateral part of calcaneum with soft-tissue swelling with specks of calcification and mid joint space reduction in mid foot joints [Figure 2]. Local ultrasound revealed multiple ill-defined hypoechoic collections seen tracking toward skin surface through multiple sinus tracts with multiple mobile internal echoes. Multiple osteolytic erosions were noted. All these findings were suggestive of chronic infective etiology. Magnetic resonance imaging (MRI) findings [Figure 3] confirmed clinical diagnosis of mycetoma with extensive bony and soft-tissue involvement of ankle and foot.{Figure 1}{Figure 2}{Figure 3}

The black grains were collected on a sterile gauze pad and crushed in between slides [Figure 4] and sent in normal saline bottles for microscopy, Gram, Ziehl–Neelsen (ZN) and periodic acid–Schiff staining, and mycobacterial and fungal culture. The grains had variable size and shape with soft consistency. ZN staining of grains was noncontributory. Light microscopic examination of crushed grains with 10% potassium hydroxide revealed multiple thick brown-colored septate hyphae. Lactophenol cotton blue staining demonstrated light brown-colored septate hyphae and single and grouped ovoid-shaped conidia with a rounded base and short conical apex with transverse and oblique septations [Figure 4]. The grains were inoculated on two tubes of Sabouraud's dextrose agar (SDA) media, each containing SDA with (at 37°C) and without antibiotic (at 25°C). Fungal growth appeared within 2–3 days. Colonies were greyish to black with floccose appearance on one side and brown on the other side [Figure 5]. The causative organism was identified as Alternaria alternata [Figure 6] on the basis of the typical macroscopic and microscopic characteristics of the fungus.{Figure 4}{Figure 5}{Figure 6}

The patient was started on oral itraconazole 200 mg twice a day. However, the extensive cutaneous, subcutaneous, and bony involvement forced the decision to perform a below-knee amputation. Postoperatively, he has been continued on oral itraconazole and is currently under regular follow-up.

 Discussion



Alternaria, a dematiaceous fungus, is considered as a weak pathogen. Soft-tissue infections by Alternaria species are usually encountered as opportunistic events in the setting of iatrogenic immunosuppression such as systemic lupus erythematosus[3] and organ transplant.[4],[5] Other risk factors include hematologic malignancy,[6] HIV, diabetes, Cushing's disease, pulmonary fibrosis,[7] and prolonged corticosteroid use. However, mycetoma caused by Alternaria appears to be extremely rare with only a single case reported so far in literature.[8] Another interesting feature about our case is the acquisition of this opportunistic infection despite complete absence of any major comorbidities or immunocompromised state.

Kpodzo et al.[6] described a case of a progressive subcutaneous A. alternata infection over the hand of a patient with chronic lymphocytic leukemia. Despite combination therapy with voriconazole and micafungin, the lesion continued to progress. Posaconazole therapy along with surgical excision of the infected tissue resulted in the eradication of infection. Gürcan et al. reported an immunocompetent patient with an erythematous scaly lesion on the foot caused by Alternaria which regressed completely with 6 weeks of oral itraconazole therapy.[9] In contrast, although our patient was also immunocompetent, the extensive involvement of subcutaneous and osseous tissue necessitated an amputation in addition to antifungal treatment with itraconazole.

The previous report of eumycetoma caused by this agent was documented from Dhule district of Maharashtra, India.[8] Their patient responded well to antifungal treatment probably due to the lack of bony involvement. Similar to most patients affected with mycetoma, our case belonged to low socioeconomic status with poor health awareness.[10] These factors, further compounded by the relentlessly progressive course and difficulty in etiological identification, probably resulted in the patient presenting at an advanced stage where unfortunately the limb could not be salvaged with antifungal therapy alone. Currently, various techniques are available to confirm diagnosis such as imaging (radiography, ultrasonography, computed tomography, and MRI), molecular techniques (polymerase chain reaction), and serodiagnosis (enzyme-linked immunosorbent assay and complement fixation tests). However, demonstration of classical grains with direct microscopy, culture, and histopathology can aid the diagnosis in resource-limited settings. Actinomycetoma usually responds well to adequate medical management. On the other hand, eumycetoma may need surgical debridement or occasionally amputation in addition to antifungals as dictated by the extent of involvement.

 Conclusion



Our case illustrates that though rare, opportunistic organisms such as Alternaria are capable of causing fulminating soft-tissue infections even in immunocompetent hosts. Early and correct etiological diagnosis of potentially mutilating diseases such as mycetoma is the key to prompt treatment initiation. The management of actinomycetoma and eumycetoma remains challenging, and all attempts must be made to avert psychologically and physically disabling surgeries such as amputation.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Gupta M. Maduromycosis of foot. Our Dermatol Online 2017;8:92-93.
2van de Sande WW. Global burden of human mycetoma: A systematic review and meta-analysis. PLoS Negl Trop Dis 2013;7:e2550.
3Akman A, Sakalli Cakcak D, Ozhak Baysan B, Yazisiz V, Terzioglu E, Ciftcioglu MA, et al. Cutaneous alternariosis in a patient with systemic lupus erythematosus. Lupus 2007;16:993-6.
4Demirci M, Baran N, Uzum A, Calli AO, Gul-Yurtsever S, Demirdal T. Cutaneous alternariasis in a patient with renal transplant. Jundishapur J Microbiol 2015;8:e19082.
5Pereiro M Jr., Pereiro Ferreirós MM, De Hoog GS, Toribio J. Cutaneous infection caused by Alternaria in patients receiving tacrolimus. Med Mycol 2004;42:277-82.
6Kpodzo DS, Calderwood MS, Ruchelsman DE, Abramson JS, Piris A, Winograd JM, et al. Primary subcutaneous Alternaria alternata infection of the hand in an immunocompromised host. Med Mycol 2011;49:543-7.
7Ioannidou DJ, Stefanidou MP, Maraki SG, Panayiotides JG, Tosca AD. Cutaneous alternariosis in a patient with idiopathic pulmonary fibrosis. Int J Dermatol 2000;39:293-5.
8Buwa S, Ingale H, Dravid M, Adchitre H. Mycetoma due to Alternaria: A case report. Int J Contemp Med Res 2016;3:1352-3.
9Gürcan S, Pişkin S, Kiliç H, Temelli BA, Yalçin O. Cutaneous infection caused by Alternaria alternata in an immunocompetent host. Mikrobiyol Bul 2009;43:163-7.
10Fahal A, Mahgoub el S, El Hassan AM, Abdel-Rahman ME, Alshambaty Y, Hashim A, et al. A new model for management of mycetoma in the Sudan. PLoS Negl Trop Dis 2014;8:e3271.