A retrospective case series: Unique clinical presentation and treatment outcomes of Trichophyton violaceum and soudanense tinea in a pediatric population.

To the Editor: Tinea capitis is an infection of the scalp and scalp hair by dermatophyte species. Clinical presentation of tinea capitis differs based on infection species and can range from mild scalp scaling to inflammatory, alopecic plaques with associated lymphadenopathy. If left untreated, it may cause permanent scarring alopecia. There are growing reports of dermatophyte infections due to Trichophyton violaceum and Trichophyton soudanense.1Grigoryan K.V. Tollefson M.M. Olson M.A. Newman C.C. Pediatric tinea capitis caused by Trichophyton violaceum and Trichophyton soudanense in Rochester, Minnesota, United States.Int J Dermatol. 2019; 58: 912-915Crossref PubMed Scopus (20) Google Scholar,2Foster K.W. Ghannoum M.A. Elewski B.E. Epidemiologic surveillance of cutaneous fungal infection in the United States from 1999 to 2002.J Am Acad Dermatol. 2004; 50: 748-752Abstract Full Text Full Text PDF PubMed Scopus (229) Google Scholar Of note, some mycology laboratories (including ours) do not report these distinct, closely related organisms separately, but instead report positive results as T. violaceum/soudanense; they are reported together in this study.3Walsh T.J. Hayden R.T. Larone D.H. Laron’es Medically Important Fungi: A Guide to Identification. 6th ed. ASM Press, 2018: 73-331Google Scholar Studies on T. violaceum and T. soudanense are heterogeneous and generally small; therefore, there is limited information on the evolving clinical presentation of this dermatophyte infection. In this retrospective case series, we identified 20 pediatric patients diagnosed with tinea capitis with positive fungal cultures for T. violaceum/soudanense from December 2021 to August 2022. Cultures were taken via a moisten cotton-tip applicator and potassium hydroxide preps were not uniformly performed across patients. Male and female patients were equally affected, the median age of diagnosis was 6 years and 90% were of African ethnicity, while the other 2 patients were either Black or Hispanic and none were white. Sixteen had a known contact with someone else who tested positive for tinea capitis (Table I).Table IDemographics of patients with tinea capitis caused by Trichophyton violaceum/soudanenseStudy participants, n = 20Sex, n (%) Male11 (55) Female9 (45)Age at diagnosis, median years (range)6 (1-12)Race/Ethnic background AmericanBlack1Latinx1White0 AfricanSomali12Of note, 8/12 were immigrants to USAEthiopian6Of note, 6/6 were immigrants to USAKnown contact with others Yes, siblings15 Yes, other1 No2 Unknown2 Open table in a new tab We found a larger variation in the location and clinical features of T. violaceum/soudanense infections than previously described with typical tinea capitis. On the scalp it presented as non-inflammatory alopecia in a moth-eaten pattern (Supplementary Fig 1, A, available via Mendeley at https://data.mendeley.com/datasets/gwryzb8nd8/1). Initially, T. violaceum/soudanense can lack inflammation and may mimic seborrheic dermatitis early on. Due to this less inflammatory pattern, clinical diagnosis and fungal culture may be delayed or missed. Location-wise, 95% of patients with tinea capitis had concomitant tinea faciei and/or tinea corporis, which is much more common than previously described.4Feußner C. Karrer S. Lampl B.M.J. An uncommon cause of tinea: trichophyton violaceum in a German kindergarten - outbreak report and quantitative analysis of epidemiological data from Europe.GMS Hyg Infect Control. 2022; 17: Doc02PubMed Google Scholar Cases involving the face and body had a distinctive inflammatory pattern, demonstrating scaly, dull red/hyperpigmented, guttate papules on the face, neck, and upper body with associated lymphadenopathy. On the body, these papules were scattered across the shoulders (Supplementary Fig 1, B and C). This pattern is a clinical clue to diagnosis, distinguishing it from other fungal entities. Treatment patterns differed than previously described. All patients were treated with either oral griseofulvin 25 mg/kg/day or terbinafine for 8 weeks with dosing based on patient weight. Based on negative fungal culture and resolution of clinical symptoms, terbinafine treatment was successful in 10/10 patients, while 9/10 patients failed griseofulvin treatment. The 9 patients who failed oral griseofulvin were transitioned to oral terbinafine and subsequently demonstrated clinical clearance (Table II). Our study is limited by a small sample size and lack of susceptibility testing, but our data support previous findings that terbinafine may be more efficacious for Trichophyton species.5Bar J. Samuelov L. Sprecher E. Mashiah J. Griseofulvin vs terbinafine for paediatric tinea capitis: when and for how long.Mycoses. 2019; 62: 949-953Crossref PubMed Scopus (13) Google Scholar Therefore, we recommend that clinicians have a low threshold for obtaining fungal cultures in suspected cases to inform therapeutic interventions. As distinct clinical presentations of tinea capitis become more common and treatment patterns vary, increased awareness is needed.Table IIPresence of inflammatory pattern and responses to treatment in pediatric patient cohort with tinea capitis caused by Trichophyton violaceum/soudanensePatientTinea facieiTinea corporisLymphadenopathyOral antifungal treatmentCured at follow-up?1+--TerbinafineY2+++TerbinafineY3+++TerbinafineY4-+-TerbinafineY5--+TerbinafineY6-++TerbinafineY7-+-TerbinafineY8+++TerbinafineY9-+-TerbinafineY10+--TerbinafineY11+++Griseofulvin, then terbinafineYes, after terbinafine12+++Griseofulvin, then terbinafineYes, after terbinafine13+++Griseofulvin, then terbinafineYes, after terbinafine14+--Griseofulvin, then terbinafineYes, after terbinafine15+++Griseofulvin, then terbinafineYes, after terbinafine16++-Griseofulvin, then terbinafineYes, after terbinafine17++-GriseofulvinY18+++Griseofulvin, then terbinafineYes, after terbinafine19+--Griseofulvin, then terbinafineYes, after terbinafine20+++Griseofulvin, then terbinafineYes, after terbinafineTotal14/20 (70%)15/20 (75%)11/20 (55%)Terbinafine – 10/20 (50%)Griseofulvin then terbinafine – 9/20 (45%)Griseofulvin – 1/20 (5%) Open table in a new tab S.M.M. is a co-founder of Stryke Club, personal care for teenage boys.