摘要
Hereditary sensory and autonomie neuropathy type IV (HSAN IV) is caused by mu tations in the tyrosin kinase A (TrkA) gene, encoding for the high- affinity re ceptor of nerve growth factor (NGF). The NGF- TrkA system is expressed in many endocrine glands. We hypothesized that HSAN IV represents a natural model for im paired NGF effect on the neuroendocrine system in humans. We have documented the clinical outcome of 31 HSAN IV patients in a single medical center, and investi gated their basal endocrine system status. The endocrine system response to thir st was compared between six patients and six healthy children. High rates of mor tality (22% ) and severe morbidity (30% ) have been found in HSAN IV patients. Hypothermia was noted in 40% of the patients and unexplained fever was observ ed in 56% . Subnormal adrenal function was demonstrated in six (30% ) of the p atients studied. Furthermore, we found lower plasma norepinephrine (NE) levels i n six HSAN IV patients compared with a control group after the thirst test. Our findings emphasize the importance of NGF- TrkA pathway in the physiology of the neuroendocrine system and its response to stress. Inadequate response to stress might contribute to the observed significant mortality, morbidity, and temperat ure instability in HSAN IV patients.
Hereditary sensory and autonomie neuropathy type IV (HSAN IV) is caused by mu tations in the tyrosin kinase A (TrkA) gene, encoding for the high- affinity re ceptor of nerve growth factor (NGF). The NGF- TrkA system is expressed in many endocrine glands. We hypothesized that HSAN IV represents a natural model for im paired NGF effect on the neuroendocrine system in humans. We have documented the clinical outcome of 31 HSAN IV patients in a single medical center, and investi gated their basal endocrine system status. The endocrine system response to thir st was compared between six patients and six healthy children. High rates of mor tality (22% ) and severe morbidity (30% ) have been found in HSAN IV patients. Hypothermia was noted in 40% of the patients and unexplained fever was observ ed in 56% . Subnormal adrenal function was demonstrated in six (30% ) of the p atients studied. Furthermore, we found lower plasma norepinephrine (NE) levels i n six HSAN IV patients compared with a control group after the thirst test. Our findings emphasize the importance of NGF- TrkA pathway in the physiology of the neuroendocrine system and its response to stress. Inadequate response to stress might contribute to the observed significant mortality, morbidity, and temperat ure instability in HSAN IV patients.
