Sir,

Aplasia cutis congenita (ACC) is a rare, etiologically heterogeneous scalp malformation characterized by the absence of the epidermis or all skin [1]. The management of ACC is a delicate process, usually involving surgical repair [2].

Herein, we report a rare case of aplasia cutis congenita, particularly in its late presentation. A five-year-old child, with no pathological history, presented scalp lesions persistent for two years. A dermatological examination revealed three, well-limited, alopecic plaques with irregular contours of variable sizes in the medioparietal region of the scalp, with a negative traction sign (Fig. 1a). Dermoscopy revealed peri-pillar scales and tufted hairs in places with a downy appearance toward the periphery (Fig. 1b). A CT scan of the skull revealed craniostenosis of the scaphocephalic type, without the need for reconstruction.

Figure 1: (a) Two well-limited, alopecic plaques involving the medioparietal region of the scalp. (b) Dermoscopic features including peri-pillar scales, tufted hair in places, and a downy appearance in the periphery.

Aplasia cutis congenita is an abnormality affecting the scalp in approx. 80–90% of cases [1]. Scalp lesions at birth are usually well-demarcated and non-inflammatory and vary in size (from several millimeters to more than 10 cm). Most lesions only involve the scalp and tend to be superficial [2]. In approx. 20–30% of patients, abnormalities of the underlying cranial bone will be associated. It has multiple etiologies implicated: genetic factors, teratogens, vascular abnormalities, drugs, and intrauterine trauma [1,2]. Cases of extensive ACC require MRI to evaluate bony and intracranial malformations. Histologic examination reveals a scarred tissue lacking skin appendages and elastic fibers. The treatment of ACC usually involves a conservative approach in the cases of simple scalp aplasia, or surgical, using skin flaps and grafts, in the case of associated bone deformities. This is to prevent bleeding and infection [2]. Aplasia cutis congenita of the scalp is a rare malformation, easily diagnosed, yet with difficult management, especially if associated with complex malformations.