How the fruit becomes toxic
Kamaranka as a cause of kidney injury is not considered even by doctors, says Dr. Eranga Wijewickrama, who urges colleagues to have it on their checklist along with painkillers etc when taking the case history of patients.
Those with kamaranka toxicity can present with hiccups (hiccoughs), nausea, irritability, agitation, reduced level of consciousness and seizures, he says, with hiccups being the commonest symptomvery suggestive of this toxicity.
Creating an image of how the nephrotoxin, oxalic acid, is absorbed into the body causing havoc with the renal system, this Nephrologist says that once the kamaranka is eaten or drunk, the nephrotoxin, like all other food and drink, gets absorbed into the body through the gastrointestinal tract (the digestive system or the alimentary canal). Thereafter, this nephrotoxin filters through the kidneys depositing the oxalic acid in the vital renal tubules, blocking them and causing oxalic nephropathy.
The renal tubule is a part of the nephron, the basic structural and func- tional unit of the kidney. The nephron also consists of a tuft of capillaries – glomerulus and the bowl- shaped Bowman’s capsule. A normal adult has about 0.8-1.5 million nephrons in each kidney. Nephron is derived from the Greek ‘nephros’ which means kidney.
Taking up the neurotoxin, though it is not his specialty, Dr. Wijewickrama says that caramboxin, on the milder side, causes hiccups, and on the more harmful side, vomiting, agitation, alternating states of consciousness and sometimes also seizures, coma and even death.
The “intoxication” from kamaranka can occur by: Tucking into the fruit as a whole regularly, such as eating one fruit a day over a period of time. Citing the example of a patient who had been eating a kamaranka per day for a year, then suddenly decided to increase it to three fruits per day for a month, this Nephrologist pointed out how he was rushed to hospital with acute renal shut- down. “This patient never recovered fully and his kidneys are still injured.” Drinking the fruit juice, with some ‘trying it’ out because it is available at the juice stalls which are a plenty in Colombo as well as most towns across the country. “The risk is more, particularly on an empty stomach and if the drinker is dehydrated, because then the system gets a concentration or full dose of the nephrotoxin. The absorption of the nephrotoxin would be quicker and there will not be anything else to flush it out when the toxin gets deposited in the tubules,” he explains. Pointing out how it works, Dr. Wijewickrama says that oxalic acid, usually gets bound to calcium and magnesium in our food, forming complexes of calcium and magnesium oxalate, preventing a large amount of oxalic acid from getting absorbed through the gastrointestinal tract. However, if kamaranka is eaten on an empty stomach, the formation of the calcium and magnesium oxalates does not occur, allowing large amounts of free oxalic acid to get absorbed, leading to nephrotoxicity.