(BMJ)—An otherwise healthy boy in his midteens had multiple horizontal linear marks on his back x2 months. FHx negative. BMI was in the 10th percentile. Exam: back: red-to-purple lines that resembled “whipping”; knees: white, atrophic lines. No central obesity, hirsutism, acne. What’s the dx?
Ehlers-Danlos syndrome
Linear focal elastosis
Cushing syndrome
Adolescent striae
Nonaccidental trauma
You are correct. A dx of physiological adolescent striae was made based on the clinical presentation. This mechanical stretching of skin and elastic fibers commonly presents on the lower back and buttocks of nonobese adolescents, without endocrine or connective tissue disorders, during a growth spurt. The parents confirmed a recent growth spurt in which the patient had gained 3 kg in weight and 6 cm in height over the past 6 months. Girls are more likely to have striae on thighs, calves, and breasts; striae develop more frequently on the knees in boys.

Cushing syndrome and Ehlers-Danlos syndrome may also cause striae, but he had no other clinical signs of these diseases. The whiplike appearance of adolescent striae may raise concern for nonaccidental trauma.

The striae on this patient’s lower back became less erythematous and flattened after tx with topical tretinoin x2 months. Striae alba on the knees became barely visible.

BMJ 2022;378:e070642
(BMJ)—A previously healthy man in his 40s had progressive blurry vision, metamorphopsia, and bilateral conjunctival edema over 3 months. Visual acuity: right eye, 20/60; left eye, 20/50. Slit lamp: chemosis. Optical coherence tomography: severe macular edema. A test confirmed the dx. What is it?
Orbital pseudotumor
Systemic lupus erythematosus
Cavernous sinus thrombosis
Allergic reaction
You are correct. Blood tests showed high titers of antinuclear and anti–double-stranded DNA antibodies, low complement, moderate leukopenia, thrombocytopenia, and proteinuria, confirming the dx of systemic lupus erythematosus (SLE). Although he had no obvious systemic manifestations, he had a primary relative with SLE, prompting the testing.

The common ocular manifestations of SLE include periocular lesions, corneal involvement, scleritis, retinopathy, and optic neuropathy. Chemosis is commonly caused by allergy, but rarely, bilateral chemosis can indicate underlying autoimmune diseases such as SLE. This unusual manifestation should prompt a clinician to consider SLE and, if appropriate, arrange further investigation and timely tx.

BMJ 2022;377:e071693
(BMJ)—A 6-year-old boy with HIV presented with a 5-month hx of enlarging lesions on his face. His family reported that he’d intermittently discontinued his antiretrovirals. Exam: multiple painless, firm, dome-shaped nodules with central umbilication. What’s the dx?
Verruca vulgaris
Kaposi sarcoma
Molluscum contagiosum
You are correct. The clinical dx of molluscum contagiosum was made based on the characteristic central umbilication. In immunocompromised patients, the lesions can become disseminated, large, and resistant to tx. Although curettage, cryotherapy, and topical treatments are among the available tx options, immunocompetent patients don’t require tx because the lesions are self-limiting and benign.

Mollusca that are large, fast growing, and refractory to tx should prompt investigation for underlying immunosuppression. If patients are already receiving tx, this presentation should prompt discussion about tx adherence.

BMJ 2022;378:e069221