BRIEF REPORT Pediatric Dermatology Tinea capitis mimicking dissecting cellulitis in three children Abstract Tinea capitis mimicking dissecting cellulitis is a rare presentation, and there is a paucity of information regarding this presentation in the literature. Three children 10-14 years of age who presented with an unusual clinical manifestation of tinea capitis that clinically resembled dissecting cellulitis are reported. The patients were treated with sys- temic antifungals for 3-4 months. Treatment success was measured according to repeat fungal cultures and clinical assessment of hair regrowth at follow-up visits. All three patients had resolution of infection, with negative repeat fungal cultures and complete hair regrowth without scarring. These cases highlight a rare inflammatory subtype of tinea capitis that can be easily misdiagnosed and there- fore improperly treated, prolonging the duration of infection. 1 | INTRODUCTION Tinea capitis, a dermatophyte infection most commonly caused by Trichophyton tonsurans, presents with varied clinical manifestations. 1-3 Noninflammatory presentations include scaly alopecic patches, alo- pecic patches with black dots, and a seborrheic variant with diffuse scaling and subtle hair loss. A hypersensitivity reaction to the der- matophyte infection causes inflammatory subtypes of tinea capitis such as kerion and favus. 4-6 Kerion presents as an inflammatory pla- que with crusting, pustules, and drainage, whereas favus presents with thick yellow crusts. 5 Because tinea capitis can have diverse clini- cal presentations, the differential diagnosis is broad and includes alopecia areata, seborrheic dermatitis, atopic dermatitis, bacterial infection, and psoriasis. 3 There have been several reported cases of an additional clinical subtype of inflammatory tinea capitis that resembles dissecting cel- lulitis. 6-12 Dissecting cellulitis is a noninfectious inflammatory condi- tion of the scalp characterized by painful nodules connected by sinus tracts, with associated scarring. 6,13 Dissecting cellulitis is most common in African American men, with one study reporting a mean age of 26 years. 13 Cases of dissecting cellulitis–like tinea capitis, in contrast, have been reported in children 9-19 years of age. 6-12 Reported cases of this variant of tinea capitis describe its presenta- tion as boggy, erythematous, interconnected plaques and nodules with overlying alopecia, 6-12 but the literature on this rare subtype is limited and it is commonly omitted in reviews of the disease. This subtype of tinea capitis is likely to be misdiagnosed because of a lack of widespread knowledge of it. Our aim is to highlight the importance of this rare tinea capitis variant in children with three illustrative cases. 2 | CASE REPORT 2.1 | Patient 1 A previously healthy 10-year-old girl presented with multiple tender, erythematous cystic plaques and nodules with overlying alopecia affecting approximately 40% of the scalp (Figure 1A). An outside provider had diagnosed her with dissecting cellulitis. Prior treatments included incision and drainage of the lesions and courses of cepha- lexin and doxycycline without improvement. Bacterial culture was negative; no biopsy or fungal culture was performed. Despite these treatments, her scalp grew increasingly edematous and painful, accompanied by worsening hair loss. She was referred to pediatric dermatology for further evaluation. Fungal culture from a lesion at the time of referral grew Trichophyton species. She was treated with prednisone for 5 days and terbinafine for 12 weeks, until hair regrowth was achieved and repeat fungal culture was negative (Figure 1B). She had full hair regrowth without scarring. 2.2 | Patient 2 A previously healthy 14-year-old boy presented with erythematous, fluctuant cystic nodules and plaques on the right parietal, occipital, and frontal scalp with overlying alopecia (Figure 2A). Outside biopsy results demonstrated deep-dermal mixed inflammation with promi- nent edema and fibrosis; Grocott methenamine silver (GMS) and Gram stains were negative. Bacterial culture was negative and a fun- gal culture was not performed. The patient was diagnosed with dis- secting cellulitis; treatment with doxycycline was unsuccessful. Upon referral, fungal culture grew Trichophyton species. The patient was treated with a 14-week course of terbinafine, until hair regrowth was achieved and repeat fungal culture was negative (Figure 2B). The patient had full hair regrowth without scarring. 2.3 | Patient 3 An 11-year-old Caucasian girl with a history of insulin-dependent diabetes mellitus presented with erythematous, boggy nodules and plaques on the scalp that were exudative and painful. Extensive alopecia was noted across the crown, approximating half of the scalp (Figure 3A). The scalp lesions had developed 18 months before; an outside provider diagnosed her with psoriasis and she was treated with clobetasol without improvement. A shave biopsy demonstrated hyphal elements, prompting initiation of itraconazole. She was referred to pediatric dermatology for evaluation of “psoriasis with superimposed tinea capitis.” She required admission to the hospital DOI: 10.1111/pde.13343 Pediatric Dermatology. 2017;1–5. wileyonlinelibrary.com/journal/pde © 2017 Wiley Periodicals, Inc. | 1