Star fruit intoxication

Star fruit intoxication can be classified into three levels according to signs and symptoms that might provide a useful guideline for institution of proper treatment mild, moderate and severe (Table 2). 

Table 2. Clinical levels of star fruit intoxication.

Seizures are present in 30% of patients with star fruit intoxication [17], and most patients have convulsive [6, 8,10,11,13,14,17,18,19] or non-convulsive [16] status epilepticus. The mortality rate of patients with seizures occurring after star fruit intoxication (severe intoxication) is significantly higher than of patients without seizures [13, 17]. Phenytoin, midazolam, diazepam and phenobarbital seem to have little or no effect on the control of persistent seizures provoked by star fruit toxicity. However, significant clinical improvement of seizure was demonstrated in one patient after the use of profofol [20]. 

Hemoperfusion was used for the first time as an option of treatment in a severe case by Chen LL et al [18] and patient consciousness returned to normal without subsequent mental confusion. Wu MY et al [19] submitted 2 patients with severe intoxication to 20 hours and 8 hours of hemoperfusion and also had good and fast improvement of the intoxication condition. In this 3 cases, 2 hemodialysis sessions in the first described patient, 1 hemodialysis session and 2 daily hemodialysis session in the patients of the second report failed to counterbalance neurotoxicity however consciousness improved dramatically after hemoperfusion [19]. A dramatic decrease in comatose time and rapid weaning from the ventilator may help reduce morbidity and mortality [19]. Hemoperfusion seems to be a promising kind of treatment to severe cases of star fruit intoxication. However this issue requires further analysis with large trials [19]. 

When behavioral recordings are coupled with electroencephalography, in a digital format, the so-called Video-EEG, allows to prove, in freely moving animals, the behavioral and EEG effects after star fruit ingestion or after local apphcation in specific brain regions of either, the crude or the purified toxin. In the first case the hypothesis that experimentally uremic animals, induced by HgCl, a known model of renal failure [48], will reproduce the star fruit intoxication effects found in the patients can be tested (see above). In the second case, the hypothesis that the crude or purified toxin per se will be able to induce behavioral and EEG activity compatible with brain hyperexcitability, possibly associated to seizures is tested. As a positive effect, the latter experimental protocol (with not relationships with renal alterations) will even validate the potential of this neurotoxin as a new tool in the neuroscience field. 

In fhe case of patienfs, fhe only reporf in which the authors claim that star fruit intoxication induce brain lesions (in this case thalamic and cortical) is the one from Chan YL ef al [11]. Unfortimafely fhere is no neurological follow up of fhe evenfual neurological sequelae thaf patienfs who survive will display in fheir future hves after the treatment s rescue. 

It is interesting to notice that the characterization of the cellular and molecular mechanisms of the star fruit intoxication needs to pass through a group of different experimental protocols among them in vivo and the in vitro bioassays. The correlation between in vivo and in vitro models is then more complex that we should think it is [53]. Thus, the particular case of synaptosomes and GABA and glutamate release and re-uptake, shows neurochemical dynamics associated to star fruit intoxication mechanisms in a preparation which consists of isolated synaptic terminals (44). However, additional studies are needed with brain slices from control brains treated with the AcTx and even the use of ex vivo models in vitro bioassays from tissue after in vivo experiments), for example, in our case, brain slices from treated animals. 

Tse KC, Yip PS, Lam MF Choy BY, Li FK, Lui SL, Lo WK, Chan TM. Star fruit intoxication in uraemic patients case series and review ofthe literature. Internal Medicine Journal 2003 33 314-316. 

Tsai MH, Chang WN, Lui CC, Chung KJ, Hsu KT, Huang CR, Lu CH,ChuangYC. Status epilepticus induced by star fruit intoxication in patients with chronic renal disease. Seizure 2005 14 521-525... 

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