Cytomegalovirus (CMV) infection is common among immunocompromised hosts; however, its cutaneous manifestation is considered rare in comparison to internal organ involvement. Clinical manifestations of cutaneous CMV infection generally include perioral or perianal ulcerations. On the other hand, autoimmune bullous dermatosis can have bullae and ulcerations similar to those caused by cutaneous CMV infection. Autoimmune bullous dermatosis requires treatment with immunosuppressive agents for relatively long periods, which may cause reduction of immunocompetence. Because of this iatrogenic immunosuppression, patients with autoimmune bullous dermatosis subsequently acquire increased risk for opportunistic infections. However, cases of bullous pemphigoid (BP) complicated by cutaneous CMV infection are rarely reported. Herein, we report the case of an 88-year-old male who had BP and subsequently recalcitrant perianal skin lesions, which were eventually diagnosed as cutaneous CMV infections.

Prurigo nodularis (PN) is a chronic inflammatory skin disease characterized by multiple nodules and papules, which are accompanied by intense pruritus. Treatment is challenging and requires a diverse approach. Recently, a few reports have described successful treatment of PN with dupilumab. We report a case of a patient with treatment-resistant PN who was successfully treated with dupilumab. Dupilumab was administered at the standard dose: an initial induction dose of 600 mg, followed by 300 mg every 14 days. Pruritus reduced after 2 weeks and almost completely disappeared after 4 weeks of treatment.

Fibrofolliculoma is a benign perifollicular connective tissue tumor that usually occurs in the face. Most fibrofolliculoma present as multiple lesions and typically occur with trichodiscomas and acrochordons, constituting the Birt-Hogg-Dube syndrome. Solitary fibrofolliculoma is nonhereditary and unassociated with other cutaneous abnormalities. A 72-year-old man visited our clinic complaining of a solitary umbilicated nodule on the antitragus of the left ear. Skin biopsy from the lesion showed a central dilated follicular infundibulum with anastomosing bands of follicular epithelium extending into the fibrous stroma. The diagnosis of a solitary fibrofolliculoma was made based on the clinical and histopathological findings. No signs of lesion recurrence for 1 year after shave removal were noted. We report a rare case of solitary fibrofolliculoma that occurred on the antitragus of the ear.

Background: A direct potassium hydroxide (KOH) smear is used to diagnose onychomycosis despite its broad sensitivity range. For a more accurate diagnosis, histopathologic examination can be used and consistently show high sensitivity. Objective: We investigated the value of histopathologic examination of the nail plate as a diagnostic tool for onychomycosis. We proposed effective routine diagnostic staining to compare sensitivity between periodic acid-Schiff (PAS) and Gomori’s methenamine silver (GMS) staining. Methods: This retrospective study was conducted from January 1, 2019 to May 31, 2020, and included 97 patients who showed negative results on direct KOH smear but had clinical manifestations that implied onychomycosis. We performed nail plate biopsy and PAS or GMS staining to identify fungal hyphae missed in the direct KOH smear. Sensitivity comparison between PAS and GMS was performed in co-stained samples. Results: Among 97 patients with 102 cases, 55 cases (53.9%) of onychomycosis were confirmed by histopathologic examination. A total of 68 patients (70.1%) had a previous medical history of antifungal agents within previous six months. PAS and GMS staining were concurrently performed in 73 cases, and onychomycosis was confirmed in 41 cases. The sensitivity of PAS was 100% (41/41), while that of GMS was 87.8% (36/41); this difference was not significant. Conclusion This study suggests that histologic examination of the nail plate is an effective tool to diagnose onychomycosis and can be performed with a direct KOH smear. Two staining methods, PAS and GMS, are recommended for concurrent performance to enhance the identification of fungal hyphae.

Background: A direct potassium hydroxide (KOH) smear is used to diagnose onychomycosis despite its broad sensitivity range. For a more accurate diagnosis, histopathologic examination can be used and consistently show high sensitivity. Objective: We investigated the value of histopathologic examination of the nail plate as a diagnostic tool for onychomycosis. We proposed effective routine diagnostic staining to compare sensitivity between periodic acid-Schiff (PAS) and Gomori’s methenamine silver (GMS) staining. Methods: This retrospective study was conducted from January 1, 2019 to May 31, 2020, and included 97 patients who showed negative results on direct KOH smear but had clinical manifestations that implied onychomycosis. We performed nail plate biopsy and PAS or GMS staining to identify fungal hyphae missed in the direct KOH smear. Sensitivity comparison between PAS and GMS was performed in co-stained samples. Results: Among 97 patients with 102 cases, 55 cases (53.9%) of onychomycosis were confirmed by histopathologic examination. A total of 68 patients (70.1%) had a previous medical history of antifungal agents within previous six months. PAS and GMS staining were concurrently performed in 73 cases, and onychomycosis was confirmed in 41 cases. The sensitivity of PAS was 100% (41/41), while that of GMS was 87.8% (36/41); this difference was not significant. Conclusion This study suggests that histologic examination of the nail plate is an effective tool to diagnose onychomycosis and can be performed with a direct KOH smear. Two staining methods, PAS and GMS, are recommended for concurrent performance to enhance the identification of fungal hyphae.