| 【Presentation of Case】
A 68-year-old woman was admitted to our emergency department due to altered consciousness for hours. She had a history of DM with retinopathy, neuropathy and nephropathy in a status of end-stage renal disease (ESRD), for which she received treatment of regular hemodialysis since 2001. Besides, she also had hypertension under medication (dilatrend 6.25 mg BID, glurenorm 30 mg BID). One day prior to this admission, she started to feel dizziness, hiccup with nausea. However, she didn't pay attention to it due to easily nausea and vomiting when smelling some food before. She kept regular hemodialysis on the next day. However, drowsy consciousness and dyspnea developed and worsened even after hemodialysis. She was brought to our emergency department. Throughout the course, there was no fever, chest pain, visual deficit, headache, joint pain, limb weakness or paresthesias. Besides, no special food intake, smoking, drug abuse, alcohol consumption or recent herb use was noted recently.
On examination, her Glasgow Coma Scale (GCS) was E3V3M6. The temperature was 36.6°C, pulse rate was 124 beats per minute, the respirations was 22 breaths per minute and the blood pressure was 142/64 mmHg. She had pale conjunctiva, isocoric pupils with prompt light reflex. Neurological examination showed that corneal reflex was normal and there was no limitation of eye movement, facial palsy, uvula deviation, tongue deviation or protrusion, or focal weakness. Laboratory examinations showed WBC 5600/μL with 92.1% neutrophils, Hgb 11.4 g/dL, Na 132 mEql/L,K 3.8 mEq/L, Ca 9.5 mg/dL, Mg 1.1 mmol/L, ammonia 9.0μmole/L, plasma glucose 242 mg/dL, serum creatine kinase (CK)/CK-MB 146/16 IU/L. Toxicologic drug screen revealed negative findings. Arterial blood gas while she was breathing ambient air showed pH 7.489, PaO2 70.9 mmHg, PaCO2 29.1 mmHg, HCO3 22.3 mmol/L. Electrocardiogram disclosed sinus tachycardia. Chest radiography revealed cardiomegaly with bilateral pulmonary congestion. Endotracheal intubation was performed immediately for prevention from aspiration. Computed tomography (CT) of the brain showed brain atrophy without any organic lesions. A lumbar puncture was performed to reveal normal CSF examinations and hormone levels of the plasma specimens were normal. She was admitted to the intensive care unit with worsening consciousness (GCS E1V1M4) despite continued hemodialysis. A clinical history was obtained from one of her family members that she ever ate one star fruit one day before admission. Under the impression of star fruit intoxication, emergent charcoal hemoperfusion for 10 hours was tried, which was switched to continuous veno-venous hemodialysis (CVVHD) due to thrombocytopenia. Consciousness recovered gradually (GCS E3V5M5 to E4V5M6). Continuous venous-venous hemodialysis (CVVHD) was then discontinued. However, deterioration of mental status reccurred with GCS E4V1M4. Charcoal hemoperfusion was prescribed again. Consciousness improved later and she was discharged uneventfully.
【Laboratory data
】
1. Results of baseline data
WBC |
Hgb |
Hct |
MCV |
PLT |
K/μL |
g/dL |
％ |
fL |
K/μL |
5.6 |
11.4 |
32.7 |
86.4 |
151 |
Amonia |
AST |
ALT |
Alb |
Glucose |
mmol/L |
U/L |
U/L |
g/dL |
mg/dL |
9 |
51 |
43 |
3.4 |
242 |
CK |
Ca |
Na |
K |
Mg |
U/L |
mg/dL |
mmol/L |
mmol/L |
mmol/L |
146 |
9.5 |
132 |
3.8 |
1.1 |
2. Results of the baseline endocrine tests
ACTH |
Cortisol |
hsTSH |
FT4 |
10-65
pg/mL |
5-25
μg/dL |
0.4- 4
μIU/mL |
6.0-17.5
pg/mL |
11 |
26 |
1.3 |
14.7 |
*** corticotropin＝ACTH , high sensitivity thyroid-stimulating hormone＝hsTSH, free thyroxine＝FT4
【病例解析】
楊桃是熱帶亞洲，包括台灣等，所盛產的農作物。在中草藥的療效方面，可以鎮咳及利尿。但若在老鼠腹腔內注射楊桃萃取液，則會導致肌肉痙攣；而直接在腦室注入，更會造成老鼠癲癇大發作。若腎功能不好的人吃了，輕則造成打嗝、嘔吐，嚴重時會讓人昏迷。至於攝取及楊桃中毐症狀發作所相隔的時間則因人而異，有30分鐘至14小時不等。初時大部分以打嗝來表現，且這類打嗝以chlorpromazine 及 metoclopramide治療無效而須以透析方式來改善。新鮮楊桃的含鉀量(重150~200克的楊桃約含7 mEq鉀)遠大於罐裝的楊桃汁，即使如此，臨床上有症狀的病人血鉀並沒有特別升高的現象。輕度的中毐症狀包括持續打嗝、嘔吐及失眠，中度症狀有肌力減低、麻痺麻木、感覺異常、躁動，重者會意識紊亂、癲癇發作甚至到昏迷及癲癇重積狀態、低血壓休克等。而有癲癇發生常表示不好的預後。在有神經症狀的病人腦部，磁振攝影水分子擴散影像(diffusion-weighted, DWI) 系列下，可見到局部或全面皮質高密度的表現( 相對應一個低的擴散係數( apparent diffusion coefficient, ADC))，另外有些區域如海馬迴等處也會有擴散強度增加(diffusion intensity)的現象。
而造成中樞神經障礙的原因：可能與楊桃內所含Averrhoa carambola類的神經毐素(可以抑制GABA神經傳遞)或草酸有關，不過詳細確實機轉仍不明。
治療方面，血液透析(尤其每日進行透析)大多可以使楊桃中毐的情況在1~12天內回復正常且不留任何後遺症。然而，有時候當傳統血液透析一停下來，中毐症狀又可能再出現。故對於較嚴重者，可以進一步採取連續動靜脈血液透析(continuous arterio-venous hemodialysis; CAVHD)、連續靜靜脈血液透析( CVVHD)。至於腹膜透析，在這類中毐是沒有任何效果，尤其是病患有意識方面的問題。若病人對以上血液透析都沒反應或呈深度昏迷、癲癇等狀態, 便須考慮以活性碳血液灌洗（charcoal hemoperfusion）來增加排出效率。而血液灌洗最常見的副作用為血小板的減少，一次平均會耗損30%的血小板，但在24-48小時內常可回復原來的數目。其次如︰低血鈣、低血糖、白血球數目減少，也是可能的副作用。
末期腎病患者發生意識障礙的時候，必須把楊桃中毐列入考慮。及時積極的血液透析治療甚或血液灌洗才能挽救病人免於死亡。
【參考文獻】
- Herbland A, El Zein I, Valentino R, Cassinotto C, Meunier C, Rieux D, Mehdaoui H. Star fruit poisoning is potentially life-threatening in patients with moderate chronic renal failure.Intensive Care Med. 2009 Aug;35(8): 1459-63.
- Tse KC, Yip PS, Lam MF, Choy BY, Li FK, Lui SL, Lo WK, Chan TM, Lai KN. Star fruit intoxication in uraemic patients: case series and review of the literature. Intern Med J. 2003 Jul;33(7):314-6.
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Case Discussion 
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