The Dietary Treatment for Four Cases of Phenylketonuria during the Past Ten Years in Taiwan

Abstract

苯酮尿症在臺灣十年來共有四例證實病人被發現。飲食療法開始時，其年齡各為十九 個月、十一個月、六歲及九歲，都已有腦神經異常及頭髮呈棕色等症狀出現。其中較 年輕之兩例接受以美國Mead Johnson公司免費提供低苯丙氨酸奶粉Lofenalac為主食 之飲食療法，而年齡較大之另兩例則僅以臺灣出產之低苯丙氨酸蔬菜、水果和穀類等 施以飲食療法。治療方法係根據病人血清內苯丙氨酸濃度，調節食品內容及份量以供 給適量之苯丙氨酸、蛋白質及熱量。血清苯丙氨酸能維持在3~7mg/d1者治療效果較佳 （例如十一個月的病例）。反之，在3~7 mg/dl範圍以外者效果較差（例如其他三例 ）。欲維持血清苯丙氨酸之濃度為3~mg/dl，則病人每天每公斤體重須攝取31~70mg之 苯丙氨酸。其中81.5%(25~57mg)，在斷奶時期之小孩需早期由其他低苯丙氨酸之食物 供給。治療效果以抽筋現象及尿氯化鐵反應之轉變最快而明顯。髮色變黑次之（二至 九週）。再次則為腦波之改善（三至七週）。而行為異常及精神運動之進步最緩慢（ 九至三十六週）。愈早以低苯丙氨酸飲食治療者效果愈佳。著者並制訂食譜以供年齡 較大之病童飲食治療用。加上此四例治療經驗，以供此後在臺灣發現苯酮尿症新病例 時實際治療之參考。 From the therapeutic experience of four cases of phenylketonuric infants and children during the past ten years, we found that the success of the treatment depended on the following factors: 1) Age at which the dietary therapy was started. Case 2, the youngest one in our series showed more remarkable improvement than others. 2) Serum phenylalanine level at 3 to 7 mg/dl frequently determined by chromatographic method. Serum phenylalanine level of 3 to 7 mg/dl was persistently kept in case 2 whose clinical improvement was very striking. Conversely, case 1 whose serum phenylalanine level remained almost below ling/ dl had failure to thrive, and case 3 as well as case 4 whose serum phenylalanine levels were possibly above 10mg/di showed little improvement . 3) Slightly higher daily phenylalanine intake than the usual amount. For example, daily phenylalanine intake of 31 to 7Omg per kg. of body weight instead of 20 to 57mg was required in case 2 to keep 3 to 7ing/dl of serum phenylalanine for the normal physical and mental development. 4) Early initiation of supplementary low phenylalanine diet in different forms in addition to Lofenalac milk is very important if the patient is about to be weaned and can tolerate it. The successful effect of the dietary therapy appeared in the following orders 1) The ferric chloride test of the urine turned negative, and seizures subsided in case 1 and 2 immediately after treatment. 2) The delta waves disappeared, and there, or fast activities showed up in the electroencephalograms done three to seven weeks after treatment. 3) The color of the hairs turned black from two to nine weeks after treatment. 4 ) Mental activities improved later about nine to thirty six weeks after treatment. Finally, we also planned a new menu of low phenylalanine diet with casual foods in Taiwan for our case 2 hereafter. And we hope it also can be used effectively for other new cases, of phenylketonuric children to be found in the future.