Subcutaneous entomophthoromycosis mimicking soft-tissue sarcoma in children

Endemic pediatric fungal infections in India: clues to diagnosis

This review is intended to familiarize readers with an emerging group of fungal infections that mostly manifest in immunocompetent individuals. This group was initially considered endemic to the tropics, but increasing worldwide prevalence has been reported. The organisms have been divided into dominant non-invasive forms and dominant invasive forms for ease of understanding. The non-invasive organisms include the group Entomophthoromycota, under which two genera Basidiobolus and Conidiobolus, have been identified as human pathogens. They present with plaques in the extremities and rhinofacial region, respectively. The invasive organisms are dematiaceous fungi (phaeohypomycosis), which includes Cladophialophora and Exophiala among others. They cause invasion of deep tissues, with the central nervous system being the most common target. The mycology, epidemiology, diagnosis, and treatment options have been summarized in brief. The clinical presentation, imaging manifestations, differentiation from other common infections and malignancies that show similar features have been detailed.

Basidiobolomycosis caused by a rare species - Basidiobolus meristosporus

A five-year girl was referred to our centre with swelling over the right lower back. The child was evaluated to rule out chronic cutaneous tuberculosis, lymphoma and soft tissue tumor. Biopsy of the lesion on culture yielded Basidiobolus species. Whole genome sequencing of the isolate identified it as Basidiobolus meristosporus. Sequencing of fungi pathogenic to humans which cannot be differentiated by conventional methods of speciation becomes essential to assign pathogenicity, understand epidemiology and resolve the nuances in the ever-evolving taxonomical classification.

Adverse effects of Lugol's iodine: Heart failure in a patient with subcutaneous phycomycosis from a resource-limited setting

Subcutaneous phycomycosis becomes a chronic, debilitating condition if left untreated. Treatment includes oral antifungal therapy, though oral potassium iodide has been used in resource-limited settings. Lugol's iodine has been an effective substitute, but little is known about its safety. We report a case of subcutaneous phycomycosis complicated by heart failure during treatment with Lugol's iodine. We review subcutaneous phycomycosis, iodine-mediated cardiotoxicity, as well as social determinants of health relevant to our case, suggesting that Lugol's iodine may only be an effective treatment with proper dosing and long-term monitoring.

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Lugol's iodine has been an alternative therapy in resource-limited settings.

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Proper dosing and long-term monitoring is essential to prevent toxicity.

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Excess iodine can cause heart failure through hyperthyroid and hypothyroid states.

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Social determinants of health may cause dosing errors and inadequate monitoring.

Subcutaneous entomophthoramycosis in a child presenting as panniculitis: a case report from Bihar, India

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The article reports a rare case of subcutaneous entomophthoramycosis.

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The patient was misdiagnosed with non-infective panniculitis, which led to extensive involvement.

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Subsequently, the patient was diagnosed correctly using standard techniques which included KOH wet mount, culture and isolation.

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Lactophenol cotton blue mount was performed for identification of the organism as Basidiobolus spp.

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The patient was cured after treatment with itraconazole and potassium iodide.

A 5-year-boy from Bihar, India was admitted to a tertiary care hospital with painful swelling over both lower limbs and buttocks, which had been increasing progressively for the past 1 year. The condition was initially undiagnosed and was later misdiagnosed as non-infective panniculitis, delaying treatment. Subsequently, the patient was diagnosed with subcutaneous entomophthoramycosis caused by Basidiobolus spp. A preliminary diagnosis was made by considering the history, clinical features, radiological findings and histopathological examination of the biopsied tissue. The confirmatory diagnosis was made using conventional techniques on aspirated pus, which included KOH wet mount and fungal culture on Sabouraud dextrose agar tubes incubated at 28°C and 37°C, respectively. Lactophenol cotton blue mount and slide culture were performed for identification of the fungal isolate. The patient responded well to oral itraconazole and oral potassium iodide.

Delayed diagnosis and extensive involvement in a rare case of subcutaneous entomophthoramycosis causing panniculitis emphasizes the importance of correct diagnosis and appropriate, effective treatment.

Entomophthoromycosis in a child: Delayed diagnosis and extensive involvement

Entomophthoromycosis is a rare fungal infection of the skin and subcutaneous tissue occurring predominantly in tropical and subtropical regions. In children, it mostly affects the lower half of the body. With this, we report a case of Entomophthoromycosis in a 6-year-old girl who presented late with extensive involvement of the upper half of the body. She responded well to treatment with potassium iodide and itraconazole. We also reviewed cases of Entomophthoromycosis reported in children.

Human Pathogenic Entomophthorales

The pathogenic entomophthoralean fungi cause infection in insects and mammalian hosts. Basidiobolus and Conidiobolus species can be found in soil and insect, reptile, and amphibian droppings in tropical and subtropical areas. The life cycles of these fungi occur in these environments where infecting sticky conidia are developed. The infection is acquired by insect bite or contact with contaminated environments through open skin. Conidiobolus coronatus typically causes chronic rhinofacial disease in immunocompetent hosts, whereas some Conidiobolus species can be found in immunocompromised patients. Basidiobolus ranarum infection is restricted to subcutaneous tissues but may be involved in intestinal and disseminated infections. Its early diagnosis remains challenging due to clinical similarities to other intestinal diseases. Infected tissues characteristically display eosinophilic granulomas with the Splendore-Höeppli phenomenon. However, in immunocompromised patients, the above-mentioned inflammatory reaction is absent. Laboratory diagnosis includes wet mount, culture serological assays, and molecular methodologies. The management of entomophthoralean fungi relies on traditional antifungal therapies, such as potassium iodide (KI), amphotericin B, itraconazole, and ketoconazole, and surgery. These species are intrinsically resistant to some antifungals, prompting physicians to experiment with combinations of therapies. Research is needed to investigate the immunology of entomophthoralean fungi in infected hosts. The absence of an animal model and lack of funding severely limit research on these fungi.

Fungi that Infect Humans

Fungi must meet four criteria to infect humans: growth at human body temperatures, circumvention or penetration of surface barriers, lysis and absorption of tissue, and resistance to immune defenses, including elevated body temperatures. Morphogenesis between small round, detachable cells and long, connected cells is the mechanism by which fungi solve problems of locomotion around or through host barriers. Secretion of lytic enzymes, and uptake systems for the released nutrients, are necessary if a fungus is to nutritionally utilize human tissue. Last, the potent human immune system evolved in the interaction with potential fungal pathogens, so few fungi meet all four conditions for a healthy human host. Paradoxically, the advances of modern medicine have made millions of people newly susceptible to fungal infections by disrupting immune defenses. This article explores how different members of four fungal phyla use different strategies to fulfill the four criteria to infect humans: the Entomophthorales, the Mucorales, the Ascomycota, and the Basidiomycota. Unique traits confer human pathogenic potential on various important members of these phyla: pathogenic Onygenales comprising thermal dimorphs such as Histoplasma and Coccidioides; the Cryptococcus spp. that infect immunocompromised as well as healthy humans; and important pathogens of immunocompromised patients-Candida, Pneumocystis, and Aspergillus spp. Also discussed are agents of neglected tropical diseases important in global health such as mycetoma and paracoccidiomycosis and common pathogens rarely implicated in serious illness such as dermatophytes. Commensalism is considered, as well as parasitism, in shaping genomes and physiological systems of hosts and fungi during evolution.

Entomophthoramycosis: a neglected tropical mycosis

The term 'entomophthoramycosis' classically refers to infections caused by members of the order Entomophthorales. A new subphylum, Entomophthoramycota, has been created to include Basidiobolomycetes, Neozygitomycetes and Entomophthoramycetes. Basidiobolomycetes encompass Basidiobolus spp., while the Entomophthoramycetes include Conidiobolus spp. Conidiobolus spp. characteristically cause rhinofacial entomophthoramycosis in apparently immunocompetent hosts. Conidiobolus spp. may also cause disseminated infection in immunocompromised patients. Basidiobolus spp. more typically cause subcutaneous entomophthoramycosis of the limbs, buttocks, back and thorax in immunocompetent patients. While once considered to be rare, there is an increasing number of reported cases of gastrointestinal infection caused by Basidiobolus spp. worldwide in countries such as United States, Thailand, Australia, Iran, Egypt and Saudi Arabia. These cases have clinical presentations similar to those of inflammatory bowel diseases, particularly Crohn's disease. Retroperitoneal, pulmonary, nasal and disseminated basidiobolomycosis have also been reported. Histology of entomophthoramycosis may reveal the Splendore-Hoeppli phenomenon. Culture of infected tissue remains the definitive method of laboratory diagnosis. However, molecular methods with specific DNA probes and panfungal primers, as well as real time PCR, are increasingly used to detect and identify these organisms in tissue. Treatment largely consists of therapy with antifungal triazoles. Surgery plays a selective role in the management of entomophthoramycosis, depending upon location, organism and extent of the infection.