Tinea incognito

Tinea Incognito: Challenges in Diagnosis and Management

Tinea incognito is a dermatophyte infection with atypical features, due to the use of topical or systemic steroids or other immunosuppressive medications. Delayed diagnosis, spread of the infection to critical body surfaces, resistance to antifungal drugs, and increased costs due to prolonged hospitalization and multiple treatment regimens often complicate tinea incognito. It can affect individuals of all ages and genders, but it is more common in children. Atypical clinical appearance often necessitates differentiation from other diseases such as eczema, seborrheic dermatitis, lupus erythematosus, psoriasis, or other non-fungal skin conditions. The treatment of tinea incognito usually involves discontinuation of topical steroids or other immunosuppressive medications. Preventive measures and management of the underlying fungal infection are necessary and can be achieved with antifungal drugs. Patients should wear loose cotton clothes, use boiling water for laundry, and iron their clothing before wearing them. Additionally, they should avoid sharing bed linens, towels, clothes, and shoes. This review aims to raise awareness of tinea incognito among health practitioners, provide tips for detecting the disorder, include it in the differentials, and evaluate the available diagnostic procedures.

Tinea Incognito

Tinea incognito (TI), or incognita, are superficial fungal dermatophyte infections that are changed in shape, most frequently because of topical, systemic steroids use and other immunosuppressants. There are different clinical presentations depending on host factors and the species of dermatophyte causing the disorder. Diagnosis can be challenging and might need combined methods. Once diagnosed the treatment is the usual antifungals, either topical or systemic or combined depending on the site, extent, and host factors.

Species Distribution and Antifungal Susceptibility Profile of Dermatophytes from a Tertiary Care Centre in North India

Objective Dermatophytoses, one of the most ancient diseases, is becoming a menace in recent times. This has made the knowledge of antifungal susceptibility a priority in today's times.

Material and Methods This is a prospective study conducted over 18 months including all dermatophytes isolated during the period. Dermatophytes were identified by routine phenotypic methods. Antifungal susceptibility testing was performed for griseofulvin, terbinafine, and itraconazole as per the Clinical Laboratory Standard Institute M38 A2, and minimum inhibitory concentrations (MICs) were read after 5 days.

Results Patient details and associated risk factors were recorded. Fixed dose combinations with steroids were associated with 79.3% (46 out of 58) of patients with dermatophytosis of skin. Among the 72 dermatophytes isolated during the study period, 58 (80.5%) were isolated from skin scrapings and 14 (19.4%) from nail samples. Tinea corporis with cruris was the most common presentation. The most common dermatophyte isolated from skin scrapings was Trichophyton mentagrophytes complex (70.6%, 41 out of 58), while from nail samples it was Trichophyton rubrum complex (78.57%, 11 out of 14). Based on the MIC50 and MIC90 results, itraconazole showed the lowest MICs, followed by terbinafine and then griseofulvin.

Conclusion With the changing epidemiology of species distribution and antifungal resistance, there is a need for continuous surveillance of these parameters of dermatophytes.

Case Report and Literature Review of Impetigo-Like Tinea Faciei

Impetigo, commonly caused by bacteria, is characterized by lesions of pustules, bullae or golden yellow crusts; it is seldom caused by fungi. Here, we report one case of a 17-year-old female patient with a 1-month history of erythematous pustules on her left cheek. She was clinically diagnosed with “impetigo”, but did not respond to 1 week of treatment with topical mupirocin cream (antibacterial agent). We then saw that a fungal colony grew on the culture, which was identified as T. mentagrophytes based on the morphological and molecular characteristics. The patient was then diagnosed with tinea faciei and was topically treated with 0.2% ketoconazole cream twice per day for 7 days. Through a literature review, we found another 18 cases of impetigo-like tinea faciei with similar clinical manifestations and pathogenic characteristics. Among these, the most common causative agent was T. mentagrophytes complex, which frequently occurs in children and adolescents and exhibits no gender preferences. Systemic and topical antifungals such as terbinafine or itraconazole are effective for impetigo-like tinea faciei caused by T. mentagrophytes complex. However, prolonged course of impetigo in more than 50% cases highlights the importance of mycological examination when dealing with apparent antibiotic-resistant impetigo cases in clinical settings.

Tinea Incognito—A Great Physician Pitfall

Tinea incognito is a dermatophyte infection exacerbated after inadequate administration of topical or systemic glucocorticoids. A 57-year-old man presented to the Department of Dermatology due to skin lesions persisting for one month. He reported having recently worked under hot conditions, in tight clothing, which caused sweating. Later, he noticed erythematous–exfoliative lesions in his groins and on the buttocks. He presented to the general practitioner who diagnosed him with eczema and prescribed clobetasole ointment. Since the skin lesions became more severe, he presented to the Department of Dermatology. On the physical examination, extensive erythematous–infiltrative lesions were observed in the area of medial, lateral, and posterior surface of both thighs and buttocks. Pustules were also present. Suspicion of tinea incognito was raised, and direct mycological examination and culture confirmed the presence of dermatophytes. The patient was prescribed topical terbinafine and oral itraconazole. Tinea incognito may be challenging to diagnose because the clinical presentation is relatively nonspecific and definitive culture or histopathological diagnosis such as by microscopic sample examination to identify fungal elements is not universally available. Every doctor has to keep in mind the fact that tinea may be a great mimicker of other dermatoses and to not prescribe medications without microscopic confirmation of tinea, and refer patients for dermatological consultation in case of doubt.

Topical steroid containing combinations: Burden of adverse effects and why the recent regulatory action may not be enough

OBJECTIVES AND METHODS

In September 2018, the government of India banned 328 fixed dose combinations (FDCs), 24 of which are combinations containing topical steroids. To assess what impact can be expected from this regulatory action, we analyzed reports of adverse drug events due to topical corticosteroids at a hospital-based pharmacovigilance center between January 2017 and August 2018.

RESULTS

Among 34 different steroid-containing FDCs responsible for 485 reports of ADEs with topical steroids, only three preparations, accounting for 50.10% of ADEs, come under the umbrella of the recent ban. Clobetasone propionate (68.87%) and betamethasone (28.45%) were the corticosteroids most frequently associated with adverse events. Most of the steroid preparations (87.84%) had been bought without a prescription for the treatment of dermatophytoses (76.70%). Males (77.73%) were predominantly affected, and nearly half (47.43%) of the patients were between 21 and 30 years of age. Skin atrophy (50.10%), striae (25.54%), and hypopigmentation (19.79%) were the major ADEs.

CONCLUSION

Nearly half of the cutaneous adverse effects were due to topical steroid combinations which are still widely available over the counter.

Tinea Corporis Masquerading as a Diffuse Gyrate Erythema: Case Report and a Review of Annular Lesions Mimicking a Dermatophyte Skin Infection

Tinea is a superficial fungal infection of the skin. Gyrate erythemas are reactive conditions that present as annular red lesions. A 61-year-old woman was diagnosed with tinea corporis whose skin lesions morphologically mimicked a gyrate erythema. She presented with diffuse annular plaques affecting the left side of her chest and abdomen that did not respond to a combination antifungal-corticosteroid cream for six-month duration. The appearance and clinical differential diagnosis included a gyrate erythema. Initial evaluation of the skin biopsy from the lesion's edge demonstrated a spongiotic dermatitis, and staining for fungal organisms was negative. However, deeper sections and a different fungal stain revealed hyphae in the stratum corneum and established a diagnosis of tinea corporis. The PubMed database was used to review the following terms: tinea corporis, gyrate erythema, and tinea incognito. Relevant papers and references cited in those papers that were generated by the search were used. Tinea corporis, especially if previously treated with topical corticosteroids, can masquerade as other dermatoses including a gyrate erythema. Correlation of clinical presentation and pathology findings is essential, especially if the biopsy results do not confirm the suspected clinical diagnosis. Consideration to perform deeper sections or additional special stains or both should also be entertained when the initial pathology observations do not support the presumptive diagnosis based on clinical morphology and history.

Malassezia (Pityrosporum) Folliculitis Incognito: Malessezia-associated Folliculitis Masked by Topical Corticosteroid Therapy

Malassezia (Pityrosporum) folliculitis usually appears as pruritic monomorphous papules and pustules on the upper back, chest, extensor arms and face. Acne vulgaris, bacterial folliculitis, eosinophilic folliculitis and systemic corticosteroid-induced acne can clinically mimic the fungal-caused acneiform condition. The designation incognito is used to describe tinea or scabies when the characteristic presentation is masqueraded by the application of topical corticosteroid treatment. Application of corticosteroid cream altered the morphology of the skin lesions in a man with Malassezia folliculitis. His cutaneous findings-localized areas of post-inflammatory hyperpigmentation with flattened or completely resolved follicular papules-raised the possibility of partially treated follicular eczema or follicular contact dermatitis. Pathognomonic findings from biopsies of the skin lesions established the diagnosis of Malassezia folliculitis; the condition completely resolved after treatment with topical antifungal shampoo and cream. Similar to tinea incognito and scabies incognito, folliculitis caused by Malassezia yeast in which the cutaneous morphology has been concealed by management with topical corticosteroids should be referred to as Malassezia (Pityrosporum) folliculitis incognito. 

Fungal Infections From Human and Animal Contact

Fungal infections in humans resulting from human or animal contact are relatively uncommon, but they include a significant proportion of dermatophyte infections. Some of the most commonly encountered diseases of the integument are dermatomycoses. Human or animal contact may be the source of all types of tinea infections, occasional candidal infections, and some other types of superficial or deep fungal infections. This narrative review focuses on the epidemiology, clinical features, diagnosis and treatment of anthropophilic dermatophyte infections primarily found in North America. Other human-acquired and zoonotic fungal infections also are discussed in brief.

Tinea incognito in Korea and its risk factors: nine-year multicenter survey

Tinea incognito (TI) is a dermatophytic infection which has lost its typical clinical appearance because of improper use of steroids or calcineurin inhibitors. The incidence of TI is increasing nowadays. We conducted retrospective review on 283 patients with TI from 25 dermatology training hospitals in Korea from 2002-2010 to investigate the demographical, clinical, and mycological characteristics of TI, and to determine the associated risk factors. More than half (59.3%) patients were previously treated by non-dermatologists or self-treated. The mean duration of TI was 15.0 ± 25.3 months. The most common clinical manifestations were eczema-like lesion, psoriasis-like, and lupus erythematosus-like lesion. The trunk and face were frequently involved, and 91 patients (32.2%) also had coexisting fungal infections. Among 67 isolated strains, Trichophyton rubrum was the most frequently detected (73.1%). This is the largest study of TI reported to date and the first investigational report concerning TI in Korea. We suggest that doctors should consider TI when a patient has intractable eczema-like lesions accompanied by tinea pedis/unguium. Furthermore, there should be a policy change, which would make over-the-counter high-potency topical steroids less accessible in some countries, including Korea.

Mechanisms of action of topical corticosteroids in psoriasis

Psoriasis is a lifelong, chronic, and immune-mediated systemic disease, which affects approximately 1-3% of the Caucasian population. The different presentations of psoriasis require different approaches to treatment and appropriate prescriptions according to disease severity. The use of topical therapy remains a key component of the management of almost all psoriasis patients, and while mild disease is commonly treated only with topical agents, the use of topical therapy as adjuvant therapy in moderate-to-severe disease may also be helpful. This paper focuses on the cutaneous mechanisms of action of corticosteroids and on the currently available topical treatments, taking into account adverse effects, bioavailability, new combination treatments, and strategies to improve the safety of corticosteroids. It is established that the treatment choice should be tailored to match the individual patient's needs and his/her expectations, prescribing to each patient the most suitable vehicle.

Tinea incognito Caused by Microsporum gypseum in a Patient with Advanced HIV Infection: A Case Report

The prevalence and the clinical relevance of dermatophytoses in HIV-infected patients are poorly documented, particularly for those caused by tinea incognito. Here, we report a case of widespread facial tinea incognito occurring in an Italian patient with advanced HIV infection, showing both skin and brain lesions. Second-line treatment with liposomal amphotericin B and cotrimoxazole, administered after a microbiological characterization of the skin scrapings, led to complete clearance of all lesions.