An inherited disorder that consists of hypohidrosis with teeth and nail anomalies.
Extremely rare, initially described in ten members of a kindred.
Autosomal dominant inheritance has been described in two families.
The hypoplastic, hypocalcified enamel defect affects all teeth in both dentitions. The general thickness of the enamel is decreased, but varies greatly in different areas of the crown. At the cervical portion of the teeth the enamel shows almost normal thickness and slightly better calcification when compared to other areas of the tooth. Dental occlusion is usually poor due to partial resorption of the enamel in the occlusal and incisal areas of the crowns resulting in a rough, moth-eaten appearance. The middle third of the enamel is pitted on most teeth. While the color of newly erupted teeth enamel varies from opaque white to a dark yellow-brown, older teeth may take on an almost black discoloration. The hardness of the enamel varies significantly. In some teeth, particularly the deciduous incisors, the enamel exhibits almost normal hardness and smoothness, while in other areas it is soft, friable, and chalky and can easily be scratched off with a sharp tool. The eruption time for the deciduous teeth is considered normal; however, for the permanent dentition it is delayed with several teeth remaining completely unerupted with some even showing signs of resorption. Generally, the skin appears dry with seborrheic dermatitis of the scalp. The hair itself is normal in texture, density, and distribution. Onycholysis of the distal parts of finger- and toenails with subungual hyperkeratosis was reported in all patients. The number of sweat glands is described as normal, but their activity is rated at less than 30% of normal. The body temperature was maintained in the normal range, but the patients generally preferred a cooler over a warmer environment.
Precautions before anesthesia
Obtain history and document loose teeth. Otherwise do routine peroperative assessment.
Careful and gentle direct laryngoscopy is required to prevent damage to the fragile teeth. Try not to allow the patient to bite down on oropharyngeal airways, endotracheal tubes, laryngeal mask airways or Yankauer suction tips, and use a soft bite block (eg, a cotton roll) instead. Hypohidrosis may potentially result in temperature disturbances.
The side-effects of atropine, glycopyrrolate, ipratropium, scopolamine, and other drugs with anticholinergic effects (eg, antidepressants, antihistamines) should be kept in mind since they all can potentially decrease sweat gland function even further.
Other condition to be considered
☞Ectodermal dysplasia: Large group of inherited disorders that arise from disturbances in one or more ectodermal structures and their accessory appendages. The absence, or deficient function, of at least ...