Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Sporotrichosis is a deep, cutaneous fungal infection caused by several species of Sporothrix of which the most common in S. schenckii , a rapidly growing dimorphic saprophytic fungus found in soil and plant matter. It can…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Seborrheic keratosis (SK) is the most common human skin tumor. It is a benign lesion that increases in incidence with age. Areas of predilection are the face and trunk, and they follow Langer lines. There are…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Seborrheic eczema (seborrheic dermatitis) is a chronic relapsing dermatitis affecting between 3% and 10% of adults, becoming more prevalent with age. It accounts for up to 3.5% of dermatology specialist outpatient consultations. It is more common…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Sebaceous gland hyperplasia (SGH) represents the most common sebaceous tumor. It is a benign proliferation of sebaceous glands. Neonatal SGH is seen in about 60% of newborns but is self-limited, requiring no treatment. Senile SGH primarily…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Systemic sclerosis (SSc), sometimes referred to as scleroderma, is a rare, multisystem disease characterized by cutaneous sclerosis, autoantibody production, and vascular abnormalities, often leading to visceral disease. It can affect any organ system, particularly the skin,…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Scleredema (scleredema adultorum or scleredema of Buschke) is characterized by progressive, symmetric induration and thickening of the skin secondary to deposition of collagen and glycosaminoglycans in the dermis. Clinically, scleredema commonly involves the posterior neck, shoulders,…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Human scabies is a pruritic condition caused by infestation with the host-specific mite Sarcoptes scabiei var. hominis , which lives its entire life within the epidermis. Transmission typically occurs via direct close contact with an infested…
Acknowledgments We would like to acknowledge the authors of this topic from the last edition: Drs Niraj Butala, Brittany Scapato, and Warren R. Heymann. Open full size image Sarcoidosis is a multisystem disease of unknown etiology characterized histologically by non-caseating granulomas. It is an immune-mediated disease, with a Th1-predominant cytokine profile. Skin manifestations are observed in approximately 25% of cases. Sarcoidosis has been reported to develop…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Courtesy of Jason Smith MD, Rome, Georgia Open full size image Rosacea is a common, chronic, heterogenous, inflammatory skin disease, seen most often in adults of both genders and all skin types. It predominantly involves the central face and is…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Courtesy of Frederick A. Perieira, MD Open full size image The taxonomy of the Rickettsiales order has been reclassified based upon updated genetic and molecular analysis. Coxiella genus and Bartonella genus are no longer considered to be a part of…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Rhinophyma is a benign cutaneous condition that is the result of hypertrophy of the pilosebaceous units of the nasal skin. This overgrowth and subsequent fibrosis can be the end result of rosacea. The Greek word phyma…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Relapsing polychondritis is an autoimmune rheumatic disorder characterized by cartilage inflammation. Characteristic features include nasal bridge, auricular and ocular inflammation, and major airway disease. It is rare with an incidence of 0.71/million/year, with an estimated increased…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Reactive arthritis (ReA), formerly known as Reiter syndrome, is a type of sterile synovitis that follows an enteric or urogenital infection. It is a type of seronegative spondyloarthropathy. This condition is thought to arise in a…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Raynaud phenomenon (RP) is characterized by intermittent peripheral vasoconstriction leading to pallor, cyanosis, and reactive vasodilatation of the arterioles of the fingers and toes. It is caused by vasospasm in response to cold, emotion, hormones, and…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Radiation dermatitis (RD) is a common complication of cutaneous radiation exposure, most frequently from treatment of malignancies or interventional radiologic procedures. Acute radiation dermatitis (ARD) typically occurs within 2–3 weeks of radiation exposure and is caused…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Pyogenic granuloma (PG), also known as a lobular capillary hemangioma , is a common benign vascular growth. It often develops rapidly into a solitary erythematous papule or polyp. PGs can be friable and hemorrhagic and frequently…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Pyoderma gangrenosum (PG) is a neutrophilic dermatosis presenting as pustules enlarging and ulcerating with violaceous, necrotic, and undermined borders healing with cribriform scarring. Multiple subtypes exist involving any skin location. PG has several associations ( Table…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Psychogenic excoriation is a psychodermatologic condition in which patients participate in destructive scratching and picking of normal skin or skin with minor surface irregularities. These behaviors may cause self-inflicted ulcers, abscesses, or scars that can ultimately…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Plaque psoriasis is a common disorder in which environmental factors contribute to the development of sharply demarcated, erythematous, scaling plaques in genetically predisposed individuals. Because there is an overlap in treatments, guttate psoriasis, and inverse psoriasis,…
Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Open full size image Pseudoxanthoma elasticum (PXE) is a rare, autosomal recessive disorder causing abnormal fragmentation and calcification of the elastic fibers in the skin, retina, and cardiovascular system. The prevalence of PXE in the population is approximately 1:50,000. The…