Neurofibtomatosis NF1 and NF2 Essay Example | Topics and Well Written Essays - 2000 words

Neurofibtomatosis NF1 and NF2 - Essay Example Thereafter, this affliction is also known as von Recklinghausen’s disease. (Von Recklinghausen, 1882). Crowe, Schull and Neel estimated that the prevalence of NF1 in the general population was 1 in 5000. Moreover, though all persons having the NF1 genes will show features of the disease, there is a large amount of variation shown in the presentation of this disease even in the same family. (Crowe, Schull and Neel, 1956). Moreover, sporadic cases are known to occur (without any family history of the disease), believed to result from germ cell mutations. (Mulvihill etal, 1990). Neurofibromatosis 2 Kantner, Eldridge, Fabricant, Allen, and Koerber found that amongst patients thought to suffer from neurofibromatosis, a certain subset of patients had propensity to develop central nervous system tumors, especially, tumors of the auditory nerves (acoustic neuromas). These patients were genetically and clinically distinct from the other neurofibromatosis patients and were subsequently identified as NF2. (Kantner, Eldridge, Fabricant, Allen, and Koerber, 1980) The prevalence of NF2 is less, estimated to be in the range of 1 in 210 000 population. (Husom, 1989.) Body Systems Affected NF1 mainly affects the skin, peripheral nerves, optic nerve, iris and long bones (e.g. those of the extremities) of the body. NF2, on the other hand, affects the central nervous system and causes the premature formation of cataract in the eyes. Characteristics of the Disease Gutman etal have summarized the features of the diseases. (Gutman, 1997). Neurofibromatosis 1 is characterized by the presence of cafe-au-lait spots, brownish colored patches on the skin. They may also display freckling in the axilla or groin. They develop tumors of the peripheral nerves called neurofibromas, which can arise in the nerve endings in the skin (cutaneous neurofibromas), peripheral nerves (nodular neurofibromas) or optic nerves (optic gliomas). Extensive tumor formation in the peripheral nerves is the most easily identifiable feature of NF1, leading to grotesque disfiguration of the face and limbs, a condition known as plexiform neurofibromatosis. The so-called Elephant Man, Mr. John Merrick is believed to be a victim of this condition. In addition, patients with NF1 may suffer from thinning of the long bones of the body. Some patients develop typical tumors in the iris of the eye called Lisch nodules. Patients with NF1 also have an increased tendency to develop other tumors like those of the adrenal gland (phaeochromcytoma), thyroid and parathyroid glands (as part of a syndrome called Multiple Endocrinal Neoplasia), small intestinal tumors and chronic myeloid leukemia. These patients often have a larger than average sized skull (macrocephaly) and are shorter in stature. Abnormalities in the functioning of the pituitary gland may lead to precocious puberty and growth hormone deficiency. They may also have learning disabilities. Other problems associated more frequently with this condition are epilepsy, headaches and deafness. The characteristic feature of NF2 is bilateral vestibular schwannomas or acoustic neuromas (tumors of the 8th cranial nerve – the auditory nerve). As a result, these patients present with gradual, progressive hearing loss. Other central nervous s