A 65-year-old retired male (Fitzpatrick phototype II) previously healthy except for a distant history of basal cell carcinoma presented to our dermatology clinic with a two-day duration of a rash. The lesions were first noticed on his chest, upper extremity and back []. The rash was extremely pruritic resulting in insomnia for the previous 2 nights which went unrelieved despite oral diphenhydramine. Also concerning to him and his wife was the whip like nature of the rash which was somewhat linear and run vertically right down his back in a manner unlikely to be produced by simple excoriation. In addition, he denied reaching for or scratching his back in any manner. Review of systems was negative, and he denied any recent history of travel, similarly sick contacts or recent outdoor contactants or change in body soaps or laundry detergents.\nHe denied any prior history of similar rashes and his past medical history was non-contributory. A detailed exposure history revealed the patient had eaten mushrooms 48 hours ago during dinner at a Chinese cuisine buffet. He admitted to ingesting great quantities of a medley of cooked and raw mushroom including the Shiitake mushroom variety.\nPhysical examination was striking with a truncal dominant but generalized rash in a centripetal distribution (). The lesions consisted of raised, relatively uniform erythematous papulovesicles arranged in linear arrangement. Close-up views [] confirmed the papulo-vesicular nature of the rash with multiple small papules grouped both along the breadth and length of each linear streak within an erythematous background.\nGiven the clinical history and presentation the diagnosis was consistent with a shiitake dermatitis. Flagellate patterns of eruption have also been noted in drug reactions particularly to bleomycin, peplomycin (a bleomycin derivative), docetaxel, adult-onset Still’s disease, and dermatomyositis [].\nThe patient was put on a mid-potency topical steroid (Triamcinolone 0.1% ointment applied to affected areas twice daily). The rash resolved within 1 week. It has been reported that shiitake dermatitis can also resolve spontaneously.
A 29-year-old male patient, with no prior known medical or dermatological comorbidities or any drug allergy, was diagnosed as a case of Stage IIIB testicular cancer. Contrast-enhanced computed tomography chest, and abdomen was suggestive of the lobulated lesion in paraaortic region with multiple bilateral lung nodules, mediastinal, and hilar lymphadenopathy []. Preoperative tumor marker analysis revealed serum alpha-feto protein level 12,100 ng/ml, serum beta human chorionic gonadotropin (HCG) level 2.39 mIU/ml, and serum lactate dehydrogenase (LDH) level 819 U/L. He underwent right high inguinal orchiectomy in May 2015. Final histopathology report was suggestive of mature cyctic teratoma of right testis with associated features of intratubular germ cell neoplasia []. Postoperative tumor marker analysis revealed serum alpha-feto protein level 126 ng/ml, serum beta-HCG level 2.39 mIU/ml and serum LDH level 292 U/L. Patients pulmonary and renal function tests were normal. He was started on bleomycin (30 units on days 1, 8, and15), etoposide (100 mg/m2 on day 1–5), and cisplatin (20 mg/m2 on day 1–5) based chemotherapy (BEP chemotherapy) as per our institutional protocol. However, after 3 cycles of chemotherapy, the patient started complaining of pruritic linear rashes which patient noticed first over the trunk and then gradually increased to involved skin over the chest, back, shoulder, and bilateral upper and lower limbs []. On physical examination, linear and streaked pigmentation were seen on bilateral upper limbs, lower limbs, and over chest and back. No other skin lesions were noted. There was no mucosal involvement or systemic upset. A clinical diagnosis of bleomycin-induced flagellate rash and postinflammatory pigmentation was considered. Routine laboratory investigations, including liver and renal function tests, were normal. Bleomycin was withheld from subsequent chemotherapy cycles, and the patient was prescribed betamethasone dipropionate ointment for local application twice a day for 2 weeks. On subsequent follow ups, the itching sensation was reduced was mild hyperpigmentation remained [].