Mastocytoma has been reported to appear in close temporal or spatial relationship to intramuscular injection of Hepatitis B vaccine. Here, we report a case of isolated vaccine induced mastocytoma occurring in an 8-month-old female patient.

Pityriasis amiantacea (PA) is a scalp condition characterized by thick, adherent scales that are silvery or yellow–gray in color and bind down tufts of hair. PA is associated with several underlying dermatologic conditions including psoriasis, seborrheic dermatitis, atopic dermatitis, tinea capitis, pityriasis rosea, and Darier's disease. Although there is no consensus on standard treatment, PA is generally treated with keratolytic agents and/or ketoconazole shampoo. More resistant cases may require systemic therapies, including tumor necrosis factor-alpha inhibitors. We report a case of a 57-year-old female with severe PA resistant to numerous treatments including topical steroids, salicylic acid shampoo, intralesional steroid injections, mycophenolate mofetil, adalimumab, and apremilast. Following treatment with dupilumab, our patient experienced complete resolution of her PA. These results suggest that dupilumab may have in a role in the management of treatment-resistant PA, particularly when associated with eczematous dermatitis.

Xanthelasma palpebrarum (XP) is the most common cutaneous xanthoma. It is triggered by hyperlipidemia, thyroid dysfunction, and diabetes mellitus. Madarosis, loss of eyebrows, occurs in various diseases ranging from local dermatological disorders to complex systemic diseases. Herein, we present a case of giant XP in a middle-aged female in whom bilateral partial madarosis developed. In polarized contact dermoscopy, the number of hairs on xanthoma plaque was reduced compared to normal.

People affected with severe acute respiratory syndrome coronavirus 2 can have a wide variety of symptoms. Literature and public discussion forums report persistent symptoms among COVID-19 survivors. More than 25% of COVID-19 survivors report hair loss as a persisting issue. The Centers for Disease Control and Prevention state that hair loss as a potential long-term effect of COVID-19 is currently under investigation. This report may be the first case of hair loss in the patient with postCOVID-19 infection in Saudi Arabia.

Lymphatic malformation (LM) of the body surface causes symptoms such as bleeding, pain, lymphatic leakage, or infection of the lesion, usually treated with surgical resection and sclerotherapy, with limited efficacy. The vesicles of the body surface tend to recur after surgical resection and may cause lymphatic leakage, which could be long term a burden for patients, eventually decreasing their quality of life. In recent years, the efficacy of orally administered mammalian target of rapamycin inhibitor (rapamycin) has been reported for LM and other vascular anomalies but few are reported in the East Asian population. We report the case of a Japanese female with intractable gluteal LM that was successfully treated with topical rapamycin for postoperative recurrence and hypertrophic scarring.

Porocarcinoma is a malignant tumor arising from intraepidermal eccrine duct epithelium or acrosyringium with an aggressive course. Sites of predilection include lower extremities (50%), trunk (24%), and head and neck (24%), while it is uncommon in the upper extremities and genitals. We report a case of eccrine porocarcinoma in the axillary region with axillary lymph node involvement and pulmonary metastasis in a 78-year-old male.

Koebner phenomenon (KP) or isomorphic phenomenon often helps in diagnosis of certain conditions and often reflects disease activity. Although commonly reported with psoriasis, vitiligo, and lichen planus, KP has been occasional reported with other conditions. Bullous pemphigoid has a rare association with this and we report a case with scratching being the inciting factor. A 50-year-old female with no comorbidities presented with itchy fluid-filled lesions all over the body for 15 days. Examination showed generalized distribution of bullae and vesicles with linear bulla on the forearms. Histopathology and immunofluorescence studies were conclusive of bullous pemphigoid. KP has been reported in general due to mechanical trauma, therapy, dermatoses, or reactions. KP in bullous pemphigoid is rarely reported and it is mentioned in the category IV of Boyd and Nelder classification. The linear nature of bulla in our patient was suggestive of scratching being the inciting factor for KP, which has not been reported to the best of our knowledge.

Coronavirus disease 2019 (COVID-19) has many cutaneous manifestations. We describe a 30-year-old otherwise healthy male with a generalized purpuric exanthem. Ten days after the onset of the rash, he presented with fatigue, dry cough, shortness of breath, anosmia, and ageusia and was diagnosed as having COVID-19. The presence of an extensive exanthem in an otherwise healthy patient could raise suspicion for underlying COVID-19.

Lethal midline granuloma is a rare aggressive, mutilating disorder of the upper airways. It is most likely secondary to natural killer/T-cell lymphoma and is difficult to diagnose owing to the varied and nonspecific symptoms. It is usually prevalent in the fourth decade of life and carries a poor prognosis. Our patient was a 19-year-old male with disease duration of 3 months, was diagnosed with lethal midline granuloma based on clinical examination, histopathology, and immunohistochemistry. The patient responded well to the first cycle of chemotherapy.

Tinea incognita is a phenomenon occurring when a fungal infection is erroneously treated with topical corticosteroids. This worsens the underlying infection without becoming clinically apparent until treatment is withdrawn, in which case the tinea infection becomes acutely symptomatic. We herein report a case of tinea incognita in a young woman treated with high-potency topical corticosteroids, leading to worsening dermatophyte infection and coinfection with Klebsiella oxytoca. The resulting infection required aggressive oral and topical antimicrobial treatment before resolving. This case illustrates the potentially harmful sequelae of using high-potency topical corticosteroids without first ruling out tinea infection.

Lichenoid drug reaction is a cutaneous drug eruption due to a Type IV delayed hypersensitivity reaction. It usually occurs months to years following the intake of the drug and is characterized by purple, flat, polygonal papules that spread symmetrically and diffusely across the body. We report the case of a 26-year-old female, who was on chlordiazepoxide for the treatment of insomnia, and presented with multiple, annular, purple, scaly, itchy plaques over her breasts. The eruption progressed to involve the thighs and buccal mucosa and did not respond to topical antifungals. Skin biopsy revealed lichenoid lymphocytic infiltrate consistent with lichen planus. After discontinuation of chlordiazepoxide, her skin eruption significantly improved within 3 months. To our knowledge, this is the first case report of a patient who developed a lichenoid drug reaction to chlordiazepoxide.

Searching symptoms on the internet and self-diagnosis is being criticized for its uncertainty in the diagnosis. However, it may help the patient and the doctor in the diagnosis and management of a disease. In this article, we present a case where the use of smartphone and internet search helped the patient and the doctor in the initial management and diagnosis of paederus dermatitis. A 34-year-old male, an urban inhabitant, noticed pain on the right side of his neck while he was sleeping at night. He woke up and noticed a beetle on his pillow. As the beetle was an unfamiliar one, he took pictures on his smartphone and searched about the beetle on the internet. From the results, he identified the beetle as “Nairobi fly,” self-diagnosed it as “paederus dermatitis,” and washed the area with soap and water to remove vesicant secreted by the beetle. Next day morning, he presented with severe pain and mild erythema on the right side of the neck. The diagnosis becomes obvious from the images shown by the patient. The patient was treated with a topical steroid and oral antihistaminic for 7 days. The patient recovered from dermatitis on the 10^th day.

Connective tissue nevi (CTN) are hamartomas consisting of the various components of the dermal connective tissue. The predominant element of the extracellular connective tissue within an individual nevus can be collagen, elastic fibers, or glycosaminoglycans. Those predominantly composed of collagen are called collagenomas. CTN can be classified as congenital or acquired, and independent or in association with a systemic disease. Collagenomas are asymptomatic and can be seen over the trunk, arm, thigh, and soles. We present the case of an 18-year-old boy with an isolated collagenoma over the lower back.

Chronic exposure to ultraviolet light causes wrinkles and dyspigmentation. Imiquimod cream is an immune-modulator medication approved for the treatment of genital warts, actinic keratosis, and superficial basal cell carcinoma. Few scientific papers were published in the literature on the effect of imiquimod on photodamaged skin. We report four patients with benign and malignant cutaneous neoplasms who were treated with 5% imiquimod cream and noticed improvement in their skin appearance. We believe that imiquimod cream is a safe and effective option for improving photodamaged skin with excellent safety profile.

Glomus tumor is a benign vascular tumor derived from modified smooth muscle cells of the glomus body. Although they can develop in any part of the body, they commonly do so in the upper extremities, most frequently in the subungual region of fingers. They can be either solitary or multiple. Extradigital glomus tumors are often misdiagnosed owing to their nonspecific clinical presentations and unusual locations. We report two cases of extradigital glomus tumor occurring at unusual sites such as knee and thigh.

Herpes zoster infection represents a localized reactivation state of latent varicella-zoster virus. Zoster presents as a grouped vesicular rash on an erythematous base distributed over sensory dermatomes. Disseminated zoster is defined as the presence of >20 vesicles outside the primary area or adjacent dermatomes. Atypical manifestations of zoster infection, especially in immunocompromised patients, may lead to delayed diagnosis, infection dissemination, and potentially life-threatening systemic complications. Bacterial superinfection of zoster lesions is a common complication; however, more serious deep soft-tissue infection is not. Here, we present two atypical cases of zoster infection, which needed a high index of suspicion to avoid misdiagnosis and inappropriate treatment. Our first patient is a 30-year-old Saudi male, with systemic lupus erythematosus on oral steroids who presented with a tense vesiculobullous eruption over two adjacent dermatomes. Biopsy revealed herpes infection. The second case is for a 58-year-old diabetic female who presented to the emergency department for evaluation of an extremely painful eruption in a dermatomal distribution 1 week after zoster resolution. Clinical and radiologic evaluation of the lesions identified necrotizing fasciitis. Although zoster commonly affects immunocompromised individuals, the atypical presentation of the initial lesions in our two patients was challenging. A high index of suspicion is required for early detection, with special consideration of the painful lesion in a cropped configuration.

Alopecia areata (AA) is an autoimmune disease characterized by nonscarring hair loss. Alopecia universalis (AU) is the advanced form of AA characterized by complete scalp and body hair loss. Traditional medical therapies for AA include topical and intralesional corticosteroids, topical anthralin immunotherapy, and light therapy. Tofacitinib is a Janus kinase-1 and 3 inhibitor used in the treatment of AA. In this report, we describe a 20-year-old female with AU refractory to topical therapies; thus, she was started on tofacitinib. Mild peripheral neuropathy was an unanticipated side effect that could be kept into consideration.