An X-linked dominant inherited syndrome characterized by follicular atrophoderma in combination with hypotrichosis, hypohidrosis, and nevoid basal cell carcinomas.
Bazex Syndrome; Acrokeratosis Paraneoplastica; Follicular Atrophoderma-Basocellular Proliferations-Hypotrichosis Syndrome; Follicular Atrophoderma-Basal Cell Carcinoma Syndrome.
First described in 1966 by A. Bazex, A. Dupré, and B Christol in six members of one family. In 1996, A. Kidd et al reviewed all the cases reported at that time and found 120 identified cases from 15 kindreds. Hitherto, approximately 150 cases have been described, all affecting Caucasians, although a very similar disorder was described in a Japanese family.
The incidence and prevalence remain unknown.
X-linked dominant inheritance. The mutations for this defect have been mapped to chromosome Xq24-q27. In affected males, the disease is uniformly severe, whereas female heterozygotes tend to be more variably and overall less severely affected due to lyonization.
Based on the characteristic clinical features of affected patients and the appearance of their hairs under the scanning electron microscope. In contrast to the frequently used term follicular atrophoderma, the histologic analysis of these skin lesions fail to demonstrate signs of atrophy.
Individuals present with follicular atrophoderma (pitting or so-called multiple icepick marks, which are funnel-shaped, round, regular, and wide follicular depressions of the skin) since early infancy on the dorsum of their hands, on the extensor surfaces of the elbows and knees and occasionally on the face and scalp. Milia (orthokeratotic keratin-filled cysts 1-2 mm in diameter, also known as “milk spots”) occur in about two-thirds of patients and are present since birth on the face, limbs, and buttocks. These milia tend to decrease in number or even disappear spontaneously around puberty. An association of milium cysts with basal cell carcinoma has been described. Basal cell nevi are common and often found in areas with follicular atrophoderma. Mainly facial and often multiple basal cell carcinomas start to develop between 15 and 25 years of age. Hypotrichosis is diffuse, found in almost all patients and affecting all body regions including eyelashes and eyebrows. Microscopy reveals pili bifurcati and trichorrhexis nodosa with flattened and twisted appearance of the hair shaft. A generalized reduction in perspiration (hypohidrosis), particularly on the face, is found in more than half of the patients. Some patients may also show circumscribed deficiencies of sweat glands. A triangular face, pinched nose with hypoplastic alae nasi, and prominent columella are considered other characteristic manifestations. No other systemic abnormalities are associated.
Precautions before anesthesia
Routine preoperative assessment and examination. There are no specific anesthetic precautions related to this disorder.