Subcutaneous zygomycosis (also known as "entomophthoromycosis basidiobolae", subcutaneous phycomycosis, and basidiobolomycosis) is a both human and non-human animal disease or lesion caused by the granulomatous infection of subcutaneous tissue by<unk> . Several enzymes produced by<unk> , including lipase and protease, might hydrolyze and utilize the fatty tissues of the host and contribute to the pathogenesis of the infection. Prevalence, mode of transmission Considering the broad-range distribution of<unk>  and its high ubiquity, subcutaneous zygomycosis is not really prevalent. In addition, the fact that infections were only reported at tropical and subtropical regions further limits its prevalence. Currently, the reason why the infections were limited to those regions is not fully understood. However, the low prevalence might be explained by the speculations that the widespread immunity of other species was developed against its infection or the number of the<unk>  strains with pathogenic characteristics is much lower than the saprophytic strains. Its transmission mode has not been fully understood though certain general ideas about its transmission are widely accepted. Ingestion of<unk>  is thought to help disperse the agent through the deposition of feces at a distant place where human and other non-human animals might be exposed. As well, the agent may transmit through traumas or insect bites on skin. Vulnerable groups Most of the reported cases were from Nigeria and Uganda in Africa as well as Indonesia and thus the residents there might be considered as one of the vulnerable groups. Over 90% of the reported infections occurred on the people under 20 years old; thus the young are thought to be a particularly vulnerable group for this agent. Based on the skewed male to female ratio of infection reported in Nigeria (3:1) and Uganda (3:2), males are substantially more vulnerable to infection. One explanation that has been offered for this observation suggests that male children in endemic regions areas were likely to use decayed leaves which might be associated with pathogenic<unk>  strains as toilet paper following defecation. Although rarely, the agent can cause gastrointestinal disease which does not show specific vulnerable groups or risk factors. Clinical features and diagnosis In general, the clinical presentation of subcutaneous zygomycosis is quite identifiable and characteristic and the diagnosis is fairly easy. Human infection is characterized by the single formation of enlarging, painless and firm swelling in soft tissues on extremities e.g. buttocks, thighs, perineum, trunk. However, as the infection worsens, symptoms such a burning sensation or itchiness may develop in the swollen region. In addition to general severe symptoms, one unusual case reported that the severe perineal infection of a led to acute large intestinal obstruction. Moreover, other rare cases also reported the infections happened on other anatomical regions such as the colon in the case of gastrointestinal basidiobolomycosis. Infections may be associated with a diffusive bluish pigmentation generally associated with swelling. Joint function is often not affected; however, a few other cases reported the subcutaneous infection transfect local muscle tissues and lymph nodes. Definitive diagnosis requires laboratory effort. Culture, histopathology and immunology can be used to for the diagnosis. First, a portion of the infected tissue will be surgically removed and used for a biopsy. Since the fungus can not tolerate refrigeration, the biopsied material needs to be incubated immediately once it is collected. Then, the examination will investigate the presence of thin-walled, wide, hyaline, coenocytic hyphae and internal cleavage for the production of the sporangiospores in H&E (Haemotoxylin and Eosin) stained sections. Other characteristics of its appearance mentioned in the morphology section might also be used to identify the species. Moreover, the histopathology test will expect a granuloma consisting of a variety of immune cells in which hypha or hyphal fragments (4–10 μm diameter) often stain bright pink in H&E sections. When biopsy is not available, immunofluorescent test can also be used to identify<unk>  strains. Five specific antigens have been identified that can be used measured in the sera of the infected patients using antibodies conjugated to fluorescein dye. The diagnosis of the rare cases, such as gastrointestinal basidiobolomycosis, is challenging given the nonspecific clinical presentation as well as the need for surgical biopsy. Treatment Many cases are thought to resolve spontaneously, although surgical intervention may be help to debulk the infected tissue. The most common treatment is taking potassium iodide (KI) on a daily basis for a half of a year to one-year period. For the patients who can not response to KI, some successful cases with other treatments also reported that medications including cotrimoxazole, amphotericin B, itraconazole, and ketoconazole might also show beneficial effects. In addition, given the fact that Conidiobolus coronatus infection causes a similar disease as<unk>  infection does, coupled with the fact that fluconazole shows great effects on treating C. coronatus infection, there might be a possibility that fluconazole will also be effective in treating<unk>  infection.
Basidiobolus ranarum
Alternaria tenuissima
Trichobacteriosis axillaris
Madurella mycetomatis
Microsporum gypseum
Microsporum fulvum
Epidermophyton floccosum
Trichomonas tenax