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Review Articles / Prace Poglądowe MYCETOMA REVISITED NOWE SPOJRZENIE NA MYCETOMA Hassan Iffat, Keen Abid Postgraduate Department of Dermatology, STD & Leprosy Govt. Medical College & Associated SMHS Hospital, Srinagar-Kashmir, India, [email protected] N Dermatol Online. 2011; 2(3): 147-150 Date of submission: 25.02.2011 / acceptance: 06.03.2011 Conflicts of interest: None Abstract Mycetoma or ‘Madura foot’ is a chronic infection of skin and subcutaneous tissues, fascia and bone. It may be caused by true fungi (eumycetoma) or by filamentous bacteria (actinomycetoma). The lesions are composed of suppurating abscesses and draining sinuses with the presence of grains which are characteristic of the etiologic agents. The introduction of new broad spectrum antimicrobials and antifungals offers the hope of improved drug efficacy. This article discusses the historical aspects, epidemiology, clinical findings, laboratory diagnosis and treatment of mycetoma. Streszczenie Mycetoma lub ‘stopa madurska’ to przewlekłe zakaŜenie skóry i tkanki podskórnej, powięzi i kości. MoŜe być spowodowane przez grzyby prawdziwe (eumycetoma) lub bakterie nitkowate (actinomycetoma). Zmiany przedstawiają się jako ropiejące wrzody i zatoki z obecnością ziaren, które są charakterystyczne dla tych czynników etiologicznych. Wprowadzenie nowych o szerokim spektrum antybiotyków i leków przeciwgrzybiczych daje nadzieję na poprawę skuteczności leczenia. W tym artykule omówiono aspekty historyczne, epidemiologię, objawy kliniczne, diagnostykę laboratoryjną i leczeniu mycetoma. Key words: mycetoma; Madura foot; actinomycetoma; eumycetoma Słowa klucze: mycetoma; stopa madurska; actinomycetoma; eumycetoma Introduction period of of several years from 1860-1874 and Mycetoma is a localized chronic, suppurative established the fungal etiology of this disorder. He and deforming granulomatous infectious disease of proposed the term ‘Mycetoma’, literally meaning fungal subcutaneous tissue, skin and bones, that is present tumor for the condition, since he found it could also worldwide and is endemic in tropical and subtropical effect other parts of the body than the foot [1]. He regions. Mycetoma is a pathological process in which the classified his cases by the colour of the grains found in causative agents – a fungus (eumycetoma) or a bacterium the sinus tracts as pale or white, black or red. Pinoy in (actinomycetoma) from an exogenous source produce 1913 recognized the possibility of classifying the cases grains. Since the treatment of these two etiologies is of mycetoma by grouping the causative organisms, and entirely different, a definite diagnosis after in 1916 Chalmers and Archibald reviewed the reported histopathological and microbiolological examination is cases and published such a classification dividing them mandatory. The disease is notoriously difficult to treat. into two groups [2,3]: Treatment consists of long courses of antifungals and Group 1 - Maduramycosis, caused by true fungi antibacterials often combined with surgery. exhibiting septate filaments usually with chlamydospores and; Historical aspects Group 2 - Actinomycosis, caused by delicate non-septate Gill, who worked at a dispensary in the southern filaments of the Actinomyces which belong to higher province of Madura, first recognized mycetoma as a bacteria. disease entity in 1842 [1]. The condition had been known there for many years. Godfrey first documented a case of Epidemiology mycetoma in Madras, India. Native people of the Mycetomas are mainly but not exclusively province commonly called the disease as ‘Madura foot’. found in the dry tropics where there is a low annual It was Vandyke Carter, who studied the condition over a rainfall. It is a disease of poverty, most commonly © N Dermatol Online 3.2011 147 affecting agricultural workers and people who are Most cases start out as a small, painless, subcutaneous habitually barefoot. The species causing mycetoma vary nodule at the site of injury. The nodule over a period of from country to country and agents that are commoner in time begins to soften on the surface and ulcerates to one region, are rarely seen in others. Actinomycete discharge a viscous, purulent, seropurulent or Streptomyces somaliensis is isolated most often from serosanguinous fluid containing characteristic granules. from patients originating from Sudan and the Middle The granules vary in size, colour and consistency East. In India, actinomycotic mycetoma is more depending on the etiological species. These grains are the commonly encountered than eumycotic mycetoma [4] . hallmark of mycetoma. However, eumycotic mycetoma accounts for the majority With time papules, pustules and nodules appear which of cases reported from the northern region [5]. also break down to form draining sinuses appearing on Men are more commonly affected than the women and the skin surface. The disease progresses to involve the the maximal incidence is seen in the age group of 21-40 surrounding tissues which become swollen, indurated years. Since it mostly affects young men, it has a and deformed by fibrous tissue reaction and multiple socioeconomic effect on the dependent family members. sinus formation. The condition is usually painless, but become very painfull with the involvement of bones or Pathogenesis as a result of secondary bacterial infection. The disease is usually acquired while Mycetoma is usually localized but may extend slowly by performing agricultural work. The organisms are direct contiguity along the fascial planes, invading the implanted subcutaneously, usually after a penetrating subcutaneous tissue, fat, ligaments, muscles, and bones. injury. It is usual to find any underlying predisposition in In eumycotic mycetoma, there may be multiple punched patients with mycetoma, and the persistence of the out lytic lesions in bones. Actinomycotic mycetoma is organism after an initial inoculation appears to be related characterized by both osteolytic and osteosclerotic to its ability to evade host defenses through a variety of lesions. The end result is gross swelling of the affected adaptations such as cell wall thickening and melanin foot or other part with serious deformity. production. Complications Etiology The disease causes disfigurement but is rarely Mycetomas may be caused by various species of fatal. In advances cases, deformities or ankylosis may fungi and bacteria, which occur as saprophytes in soil or occur. Chronic neglected infection may necessitate on the plants. Actinomycotic mycetoma is caused by amputation. Immunocompromised patients may develop aerobic species of actinomycetes belonging to the genera invasive infection. Lymphatic obstruction and fibrosis Nocardia, Streptomyces and Actinomadura. may cause lymphoedema. Complications may also result Eumycotic mycetoma is associated with a variety of from toxicity due to prolonged antimicrobial or fungi, the most common being Madurella mycetomatis, antifungal therapy. Pseudoallescheria boydii and Acremonium species. Differential Diagnosis Common causative agents of actinomycotic mycetoma: Mycetoma has to be differentiated from the Agent Grain colour following: Nocardia asteroids White • Osteomyelitis (bacterial or tubercular) Nocardia brasilienses White • Actinomycosis Nocardia otitidiscaviarum White • Botryomycosis Actinomadura madurae White • Chromoblastomycosis Actinomadura pelletieri Red to pink • Sporotrichosis Streptomyces somaliensis White-to-yellow • Atypical mycobacterial infection Common causative agents of eumycotic mycetoma:- Laboratory Diagnosis Agent Grain colour Clinical material: Madurella mycetomatis Black to brown Serosanguinous fluid or seropurulent fluid, Madurella grisea Black to brown scrapings of sinuses, tissue biopsy or excised sinus Leptosphaeria senegalensis Black should be examined for the presence of grains. Saline Curvularia lunata Black dressings applied overnight over the swelling can also be Neotestidina rosatii Yellow observed for the presence of grains. The grains Acremonium spp. White to yellow discharged from the sinuses vary in size, colour and Fusarium spp. White to pale yellow consistency, features used for the rapid provisional Scedosporium apiospermium White to pale yellow identification of the etiological agent [8,9]. Clinical presentation of the disease Direct microscopy: Mycetoma is a chronic suppurative infection of A Gram stain is of considerable value in the subcutaneous tissue and contagious bone. The distinguishing between actinomycetoma and clinical features are fairly uniform, regardless of the . eumycetoma. The fine branching filaments, only about 1 organism involved [6,7] Since trauma favours infection, micron thick, within the grains of actinomycetoma are feet are the most common site for infection and account gram-positve. The grains of eumycetoma are gram for almost two-thirds of cases. Other sites include the negative [10,11]. The filaments and hyphae of the causal lower leg, hands, head, neck, chest, shoulder and arms. agent can be stained better in biopsy samples with Gram 148 © N Dermatol Online 3.2011 stain (actinomycetoma) or Gomori methamine silver or sulphonamides, rifampicin, tetracyclines, isoniazid, periodic-acid-Schiff stains (eumycetoma). streptomycin, amikacin and amoxicillin-clavulanic acid The study of discharged granules crushed on the slide have been used with variable results [20-22]. The and stained with lactophenol blue particularly allows addition of aminoglycosides and cotrimoxazole gives differentiation between the thin filaments of