Acute Kidney Injury with Neurological Features: Beware of the Star Fruit and its Caramboxin

Exploring the care experiences of hemodialysis nurses: from the cultural sensitivity approach

BACKGROUND

Culturally sensitive care has been identified as a best-practice approach for improving health outcomes. Hemodialysis patients require culturally sensitive care because it involves totally changing their previous life. The purpose of this study was to explore the subjective experiences of hemodialysis nurses in providing culturally sensitive care to hemodialysis patients.

METHODS

A qualitative study was carried out in the hemodialysis center of a teaching hospital in northern Taiwan. Purposive sampling and semi-structured interview guidelines were employed to interview 23 hemodialysis nurses. The interviews were recorded and transcribed verbatim, and the resulting data were analyzed and summarized using content analysis by constant comparative methods.

RESULTS

Hemodialysis nurses exhibited the characteristics for delivering culturally sensitive care, which comprised five aspects: finding the true meaning of the behavior of the participants, recognizing and honoring individual psychological states, culturally sensitive communication in line with patients' values, customizing care content through cultural transformation strategies, and empowerment rather than prohibition.

CONCLUSIONS

The findings of this study on the culturally sensitive care provided by hemodialysis nurses can be utilized by nursing educators and administrators as a reference to develop and enhance the nursing education related to culturally sensitive care for hemodialysis professionals.

Antiepileptic therapy in a patient with star fruit intoxication: A case report

RATIONALE

It is rare for uremia patients to have epileptic seizures after eating star fruit, only a dozen cases are reported worldwide. Such patients usually have poor prognoses. Few patients had good prognoses, all of them were treated with expensive renal replacement therapy. At present, there is no report on the addition of drug therapy to these patients based on the initial renal replacement therapy.

PATIENT CONCERNS

A 67-year-old male patient with star fruit intoxication who had a history of diabetic nephropathy, hypertension, polycystic kidney, and chronic kidney disease in the uremic phase, and regular hemodialysis 3 times a week for 2 years. Initial clinical manifestations include hiccups, vomiting, speech disturbances, delayed reactions, and dizziness, which gradually progress to hearing and visual impairment, seizures, confusion, and coma.

DIAGNOSES

This patient was diagnosed with seizures caused by star fruit intoxication. The experience of eating star fruit and the electroencephalograms can prove our diagnosis.

INTERVENTIONS

We performed intensive renal replacement therapy according to the recommendations in the literature. However, his symptoms did not improve significantly until he received an extra dose of levetiracetam and resumed his previous dialysis schedule.

OUTCOMES

The patient was discharged after 21 days without neurologic sequelae. Five months after discharge, he was readmitted due to poor seizure control.

LESSONS

To improve the prognosis of these patients and to reduce their financial burden, the use of antiepileptic drugs should be emphasized.

Averrhoa carambola leaves prevent dyslipidemia and oxidative stress in a rat model of poloxamer-407-induced acute hyperlipidemia

Background: The star fruit [Averrhoa carambola L (Oxalidaceae)] is traditionally used in the treatment of many ailments in many countries. It possesses several pharmacological activities, including antioxidant and anti-inflammatory effects. However, it contains the neurotoxic caramboxin and its high content of oxalic acid limits its consumption by individuals with compromised kidney function. This study assessed the anti-hyperlipidemic and antioxidant activities of different fractions of the methanolic extract of A. carambola leaves (MEACL). Methods: The antioxidant activity was investigated using FRAP, and ABTS and DPPH radical-scavenging assays and the inhibitory activity toward pancreatic lipase (PL) and HMG-CoA reductase was assayed in vitro. Acute hyperlipidemia was induced by poloxamer-407 (P-407) in rats and different fractions of MEACL (n-hexane, chloroform, n-butanol, ethyl acetate (EA), water, and chloroform) were orally administered. Cholesterol and triglycerides were determined at 0, 12, 24, and 48 h and LDL-C, vLDL-C, HDL-C, lipid peroxidation (LPO) and antioxidants were assayed after 48 h. The expression of ABCA1, ABCG5, ABCG8, LDL-R, SREBP-1, and SREBP-2 and the activity of HMG-CoA reductase were assayed in the liver of P-407-administered rats treated with the EA fraction. Results: The in vitro data revealed potent radical-scavenging activities of MEACL fractions with the most potent effect showed by the EA fraction that also suppressed the activities of HMG-CoA reductase and PL. In P-407-induced hyperlipidemic rats, all fractions prevented dyslipidemia as shown by the decrease in total cholesterol, triglycerides, LDL-C, vLDL-C and atherogenic index. MEACL and its fractions prevented LPO and boosted GSH, superoxide dismutase, glutathione peroxidase, and catalase in P-407-administered rats. The EA fraction showed more effective anti-hyperlipidemic and antioxidant effects than other fractions and downregulated SREBP-2 while upregulated ABCA1 and LDL-R and ameliorated LPL and HMG-CoA reductase in hyperlipidemic rats. Conclusion: MEACL showed in vitro and in vivo antioxidant activity and the EA fraction significantly ameliorated dyslipidemia in a rat model of P-407-induced acute hyperlipidemia by modulating LPL, PL, HMG-CoA reductase, and cholesterolgenesis-related factors. Therefore, the leaves of A. carambola represent a safe alternative for the star fruit particularly in kidney disease patients, and the EA is the most effective anti-hyperlipidemic and antioxidant fraction.

Acute and sub-chronic toxicological evaluation of Averrhoa carambola leaves in Sprague Dawley rats

Averrhoa carambola is a species of tree native to tropical Southeast Asia. It possesses antioxidant and anti-hyperlipidemia effects and has traditionally been used to treat a variety of ailments. However, the presence of oxalic acid in its fruits might restrict its consumption by individuals suffering from kidney disease, and caramboxin can cause neurotoxicity. In this study, we evaluated the acute and sub-chronic toxicity of the methanolic extract of A. carambola leaves (MEAC) in male and female rats. In the acute study, female rats were given a single oral dose of 5000 mg/kg of MEAC and closely examined for distinct indications of toxic effects during the first 4 h, periodically for 48 h, and daily thereafter for 14 days. Rats of both sexes were employed in the sub-chronic investigation for the 28-day repeated dose oral toxicity study. Results of the acute study revealed the safety of MEAC up to a dose of 5000 mg/kg where the rats did not show changes or signs of toxicity. In the sub-chronic toxicity study, MEAC (250, 500, and 1000 mg/kg) administration did not affect the body weight, food, and water consumption, motor coordination, behavior, or mental alertness in the treated rats. In addition, no variations in hematological or biochemical markers were found in MEAC-treated rats. In conclusion, these findings pinpoint the safety of MEAC at doses up to 5000 mg/kg. The leaves of A. carambola could be safely consumed by people with kidney disease to treat other ailments.

Nephrotoxicity and neurotoxicity following star fruit (Averrhoa carambola) ingestion: a narrative review

In recent times, star fruit (Averrhoa carambola) nephrotoxicity and neurotoxicity have been increasingly reported, both in individuals with pre-existing renal disease and those with previously normal renal function. We summarise the clinical findings of star fruit toxicity in humans and outline the important pathogenetic insights provided by animal studies. Google Scholar, EMBASE, Scopus and PubMed were searched from 1995 through July 2020 for case reports/series on renal or neurological manifestations of star fruit toxicity in humans and mechanisms of star fruit toxicity in animal studies. Ten case series and 28 case reports in humans (total number of individuals=136) were included and 8 animal studies were analysed. Ninety-four (69.1%) patients had prior renal impairment. Renal histology showed acute oxalate nephropathy with tubulointerstitial nephritis or tubular necrosis. Neurotoxicity manifestations ranged from hiccups to status epilepticus. Oxalate and caramboxin are considered the main substances causing nephrotoxicity and neurotoxicity. Caramboxin inhibits GABA binding and activates the glutamatergic receptors. Haemodialysis improved outcomes in neurotoxicity. Nephrotoxicity and neurotoxicity need to be looked for with star fruit toxicity, both in individuals with abnormal or normal renal function. Once star fruit intoxication is identified, early renal replacement therapy should be considered. Further studies on the mechanisms of star fruit toxicity are needed.

Nutritional and medicinal properties of Star fruit (Averrhoa carambola): A review

Star fruit (Averrhoa carambola), a popular fruit in many parts of the world, is considered to have many beneficial nutritional and medicinal effects. However, harmful nephrotoxic and neurotoxic effects have also been described. In this review, we have discussed the reported beneficial effects of star fruit, explored the potential mechanisms for such beneficial effects, and outline factors that may affect the safe level of consumption. The beneficial effects include the following: antioxidant (mediated via L-ascorbic acid, epicatechin, and gallic acid), hypoglycemic (mediated via high fiber levels and 2-dodecyl-6-methoxycyclohexa-2,5-diene-1,4-dione), hypotensive (mediated via apigenin), hypocholesterolemic (mediated via micronized fiber), anti-inflammatory, anti-infective, antitumor effects, and immune-boosting effects. The presence of chronic kidney disease, gastroenteropathies, chronic pancreatitis, dehydration, consumption on an empty stomach, and higher concentration of oxalate in fruit/juice consumed predisposes to toxicity. The level of ingestion at which the beneficial effects transition to nephrotoxicity and neurotoxicity is still to be accurately ascertained. Furthermore, the relationship between the amount of star fruit ingested and the severity of toxicity is not certain and warrants further study.

Mechanisms of star fruit (Averrhoa carambola) toxicity: A mini-review

The star fruit (Averrhoa carambola) is consumed in high amounts in Asia and Central/South America. It contains oxalic acid and caramboxin. In some individuals, its ingestion may lead to nephrotoxicity and neurotoxicity. The nephrotoxic effect is due to oxalate deposition in renal tubules resulting in acute tubular necrosis and interstitial nephritis. Although uraemic encephalopathy secondary to acute kidney injury may play a role, a shift to an excitatory state of the central nervous system (CNS) by caramboxin through activation of excitatory neuroreceptors and inhibition of GABA receptors leads to mental confusion, seizures and status epilepticus seen with star fruit intoxication. In this mini-review, we discuss the mechanisms of star fruit-related toxicity.