[Brown facial pseudochromhidrosis in a child: A bacterial disease?] / Pseudochromhidrose faciale brune, une maladie bactérienne ?

INTRODUCTION: Pseudochromhidrosis denotes the production of colourless sweat that acquires colour after coming into contact with exogenous factors such as dyes in clothing, chemicals or chromogenic microorganisms. PATIENTS AND METHODS: A 9-year-old girl presented with progressive brown pigmentation predominantly on the nose, forehead, perioral region and cheeks. It was easily removable by rubbing with a moist compress, leaving normal-coloured skin as well as brown pigment on the compress. The same pigmentation recurred within 2h. The patient was not using cosmetics. Bacteriological culture of samples taken by rubbing the skin in affected areas on the face was positive for commensal bacteria of the skin (Actinomyces viscosus, Staphylococcus epidermidis, Cutibacterium acnes and Streptococcus sanguinis). Antibiotic therapy achieved total resolution of symptoms. CONCLUSION: Bacteria constitute the most frequent aetiology of pseudochromhidrosis. Where such a cutaneous condition exists, even in the absence of positive bacteriological testing, antibiotic therapy would seem to be indicated as a therapeutic test. Biopsy does not appear to be essential as a first-line approach where a bacterial cause is suspected, but it may be proposed in the event of resistance to antibiotics.

[Childhood postinfectious erythema multiforme]. / Érythème polymorphe postinfectieux de l'enfant.

Postinfectious erythema multiforme is an uncommon skin disease in childhood that can have a strong impact, especially in infants if there is involvement of the mucous membranes. The lesion is targeted (central bullous lesions with three concentric circles). Its diagnosis is typically made clinically. Atypical forms are the highly inflammatory, mainly bullous type, with exclusive involvement of the mucous membrane, or recurrent erythema multiforme. The diagnosis of erythema multiforme is frequently suspected in children with urticaria multiforme. Kawasaki disease and toxic epidermal necrolysis may have a target-like skin aspect with mucosal involvement, and should be considered when planning treatment. The two major infectious etiologies in children are Mycoplasma pneumoniae and Herpes simplex. More recently, postvaccination erythema multiforme has been reported with the majority of vaccines used in pediatric practice. The prognosis is usually good but requires observation of the mucosal involvement because of the risk of serious complications. The treatment of erythema multiforme is essentially symptomatic, with etiology-related treatment.