Primordial bird-head nanism associated with progressive ataxia and multiple endocrinopathies.
Only two siblings from nonconsanguineous Norwegian parents have been described.
Inheritance is most likely autosomal recessive.
At the time of description, the older individual was a 26-year-old man and his sister was 16 years old. Both had dwarfism (proportionate short stature), a characteristic bird-like face with microcephaly, receding forehead, hypotelorism with small, deep-seated eyes, prominent and curved nose, micrognathia with crowded teeth, and clinodactyly of the fourth finger. Both siblings were mentally delayed and suffered from progressive ataxia and epilepsy. Multiple endocrinopathies included goiter, primary gonadal insufficiency, and insulin-resistant diabetes mellitus (DM). Thyroid-stimulating hormone (TSH) was elevated in one, but both were clinically euthyroid. The age at onset of DM in the male was 16 years. While fasting plasma glucose normal in the girl at the time of publication, she was considered glucose-intolerant due to her severe hyperinsulinemia. Parathyroid hormone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and adrenocorticotropic hormone (ACTH) levels were also elevated. Since polypeptide hormones act via cell membrane receptors, it has been hypothesized that a generalized cell membrane defect might be responsible for this syndrome.
Precautions before anesthesia
Assessment of the endocrine status is paramount prior to anesthesia. Hypothyroidism is most likely already treated with thyroxine; otherwise, elective surgery should be postponed until the patient is euthyroid. DM treatment and glycemic control should be reviewed and optimized if necessary. Adrenal insufficiency should be suspected, and depending on the extent of the procedure, a stress dose of steroids will be indicated. Relative resistance not only to insulin but also to other external hormones might be present. Treatment for seizures and hypothyroidism should be continued until the morning of surgery and resumed postoperatively as soon as possible. Developmental delay may cause agitation and stress in the perioperative period; thus, anxiolytic and sedative premedication and/or presence of a parent (or primary caregiver) for induction of anesthesia may be beneficial.
Depending on the degree of the facial abnormalities, airway management may be difficult. Maintenance of spontaneous ventilation is recommended until the airway has been secured. Alternative airway management options should be immediately available (eg, supraglottic airway device, fiberoptic bronchoscope), and adherence to an established difficult airway algorithm is advised. A surgeon familiar with surgical airway management and the necessary equipment should easily be available in the operating room. Alternatively, an awake fiberoptic intubation should be considered.
Chronic antiseizure treatment may interfere with the metabolism and elimination of other drugs that share the same metabolic pathways. Etomidate and ketoconazole can temporarily depress adrenal function and should therefore be avoided in these patients. Similarly, megestrol (synthetic progesterone), metyrapone (reversible inhibitor steroid 11β-hydroxylase), ...