AIDSにおける神経障害と治療

Neurological involvements of AIDS and their treatments.

はじめに

　1981年に米国で最初の患者が報告されて以来，AIDS（Acquired Immunodeficiency Syndrome）は治療薬の開発を含む多方面からの研究にもかかわらず，現在なお非常な勢いで増加しつづけており，ちょうど10年後の1991年4月1日現在，米国の167,803人をはじめとして全世界で345,534人の患者が届け出られている^1）（図1）。米国では，既に若年者の死因の第1位を占め，全人口でも心臓病，癌，脳血管障害に次いで第4位を占めようとしている^2）。我が国でも，1985年3月に第1例が発生して以来，年とともにその数は確実に増加しており，1991年2月現在374人の患者と1,640人のキャリアが届け出られている（図2）。ただ欧米，とくに米国と比べて我が国での流行は今までのところ比較的軽く，これは社会的な背景に基づく感染源の違いによるところが大きいと考えられている。すなわち，米国では男性同性愛者が64％，麻薬常用者17％，同性愛＋麻薬常用8％が大部分を占め，血友病患者および輸血によるものは2.5％にすぎない^3）のに対し，我が国では血友病患者に対する凝固因子製剤使用によるものが，全患者の75％，キャリアの86％を占めているのが特徴的である（表1）。

Since the first case of AIDS patient was reported in 1981, the numbers of patients with AIDS and HIV carriers have increased explosively through the world. By March 1991, 345, 534 of patients with AIDS were reported to the World Health Organization from all over the world. In U.S.A., AIDS is becoming the 4-th cause of death, following to cancer, cardiac disease and cerebrovascular disease. In Japan, the first patient was found in March 1985. Since then, 374 of AIDS patients and 1,640 of HIV carriers have been notified to the Ministry of Public Welfare by the end of February 1991. Fortunately so far, epidemics in Japan is not so large as in foreign countries like U.S.A., France and so forth. The most important reason for this difference seems to be due to the different incidence of each risk factor for HIV infection between Japan and other countries. In U.S.A., 64 percent of AIDS patients are homosexual men, 17 percent intravenous drug abuser, and 8 percent homosexual men with drug abusers. In contrast, 75 percent of AIDS patients and 86 percent of HIV carriers in Japan are hemophilias. Although risk factors are different, patients in Japan are supposed to have almost the same spectrum of neurological complications of AIDS as in foreign countries. At the present time, the prevalences of each neurological complication in Japan is difficult to compare exactly with those in these foreign countries, because too few patients were comfirmed their diagnoses by either autopsy or brain biopsy in Japan. This problem must be investigated further.