Huntington s Correa: a Slow Death. Liam Stacey

Transcription

1 Huntington s Correa: a Slow Death Liam Stacey

2 History HC has been recognized as a medical disorder from as early as the Middle Ages, causation, however has only recently been determined. Was simply known as Correa for the herky-jerky manner in which the afflicted persons would move. First definite mention of HC was by Charles Oscar Waters in the medical publication Practice of Medicine, in the year A 22 year old medical student, George Huntington, was the first one to officially break down HC s pathology in Reserch and support groups specifially for HC werent formed until the 1960 s

3 Quote by Huntington "Of its hereditary nature. When either or both the parents have shown manifestations of the disease..., one or more of the offspring almost invariably suffer from the disease... But if by any chance these children go through life without it, the thread is broken and the grandchildren and great-grandchildren of the original shakers may rest assured that they are free from the disease."

4 Introduction HC is a genetically inherited disorder, with 92% of the people afflicted first showing signs between the ages of But, 8% show signs at or before the age of 20. Has been known to develop earlier in each successive generation effected. Child of affected parent has ~50% chance of developing the disease themselves. HC affects between 4-15 of every hundred thousand people of European decent, and is even more rare in people of Asian decent. Effects both men and women equally, as is the norm in genetic disorders.

5 Symptoms Early stage symptoms are subtle in nature, with gradual changes in personality, speech, cognition, and motor skills. These can be present up to 3 years before general onset of HC Those effected commonly underestimate the situation they find themselves in. As the disease progresses: independent movement becomes nearly impossible due the Correa (random uncontrollable movements), slowed eye movement, swallowing and speech decline to nearly impossible levels (commonly causing severe weight loss), unusual facial expressions, and severe sleep disturbances. The mental aspects are even more debilitating: progressive decline in cognitive abilities including planning, abstract thinking, both episodic and procedural memory, and eventually full on dementia.

6 Disease Mechanisms Is caused overall, by the widespread death of brain cells attributable to a mutation in the aptly named Huntington protein. This protein interacts with over 100 different proteins, but its non-mutated functionality is at present unknown. Once mutated the H. protein becomes extremely toxic to certain cell types, particularly brain cells. Early damage becomes most noticeably apparent in the Striatum, hence the problems with movement, and higher cognition.

7 Effect on the Brain As previously mentioned HC s early damage is most noticeable in the Basal Striatum, particularly the caudate nucleus and the putamen. However many other areas are eventually profoundly effected including: the substantia nigra, layers 3,5,6 of the cerebral cortex, the hippocampus, Purkinje cells, the hypothalamus and parts of the thalamus. Also causes an unusual activation of the brain s own immune cells, and astrocytes.

8 Diagnosis and Treatment There is NO known cure for Huntington s Correa. Physical diagnosis can be done once these symptoms have began, but a genetic test can be done at any time in ether a confirmatory or precautionary manner. Medications to help treat the Correa are Tetrabenazine (2008), along with other neuroleptics and benzodiazepines. But really relegated to different management therapies with those afflicted eventually requiring full-time multidisciplinary caregiving.

9 Ethical Issues The fact that genetic testing can be done at any age regardless of symptom manifestations has raised several ethical issues. Chief among these concerns is the age at which one is mature enough to consent to a test being done, and whether or not parents should have the right to forcibly have their children tested. Additionally there is also controversy as to wether or not these tests should be administered in regards to employment, health and life insurance. Thankfully Dr. Charles Davenport s 1910 suggested plan of forced sterilization of family lines found to have HC, didn t take root.

10 Prognosis Patients are usually deceased between 15 and 20 years after initial diagnosis. Many deaths occur as a result of falls or other physical accidents due to the nature of HC. HC patients are extremely vulnerable to both pneumonia and heart disease which claims nearly one-third of these patients. Sadly, approximately 27% of Huntington s patients attempt to take their own lives, with ~ 10% succeeding with suicide. It is unclear if the pathology of the disease itself contributes to suicidal thoughts.