Scarlet fever is a childhood disease that is caused by a reaction to erythrogenic toxin produced by Streptococcus pyogenes (GAS). Scarlet fever is primarily a clinical diagnosis based on fever, pharyngitis, and the classical scarlatiniform rash. It peaks at 4…
Polymorphic eruption of pregnancy – aka pruritic urticarial papules and plaques of pregnancy – is a benign, self-limited skin condition that is characterised by erythematous papules and urticarial plaques during the third trimester or immediate postpartum period. It typically affects…
Pityriasis rosea is a self-limiting skin disorder characterized by a solitary oval-shaped herald patch followed by smaller erythematous papulosquamous lesions in a characteristic ‘Christmas tree’ distribution along Langer lines. It is associated with HHV-6 and HHV-7 reactivation. Pityriasis rosea vs…
Periorificial dermatitis is an inflammatory skin disorder that is characterised by eruption of multiple erythematous papules and pustules around the orifices – eyes, nose, and mouth. Most cases are associated with topical steroids or cosmetics. It commonly affects young women.
Molluscum contagiosum is a skin infection caused by molluscum contagiosum virus (MCV) – a DNA pox virus. It appears as skin-coloured white papules with central umbilication.
Keratoacanthoma is a rapidly growing, self-resolving, low-grade cutaneous tumour; it is often mistaken for squamous cell carcinoma. It presents as a solitary, dome-shaped nodule with a central keratin-filled crater.
Intertigo is dermatitis affecting skin folds. It is commonly complicated by a secondary fungal infection. It appears as an erythematous rash on a skin fold.
Hyperhidrosis refers to sweating excessively, beyond the physiological needs of thermoregulation and emotional stimuli. Classification of hyperhidrosis Classification Features Primary hyperhidrosis Affects specific body regions, e.g., axilla, palms, plantar area, craniofacial area, or inguinal region Secondary hyperhidrosis Generalized sweating (due…
Dermatitis herpetiformis is a chronic, pruritic, autoimmune, blistering skin condition. It is the cutaneous manifestation of coeliac disease. It presents as clusters of small vesicles or papules on the extensor surfaces (elbows, knees, and buttocks). It peaks at 30 –…
Atopic eruption of pregnancy is characterised by pruritus and rash (eruption) during the first and second trimester of pregnancy. It is the most common skin condition of pregnancy. The diagnosis is clinical. It is more common in women with atopy…