Lily Toxicosis

A 2-year-old, spayed, female domestic shorthair presented with a 24-hour history of lethargy, depression, and anorexia.

History. She was an indoor cat, the only pet in the household, FeLV/FIV negative, and current on all vaccinations. The owners reported no previous health problems. They had come home the previous night to find several piles of vomitus around the house and casually reported that one pile contained a plant leaf. The vomiting resolved overnight, but the next day the cat became progressively more lethargic and refused all food.

Physical Examination. The cat was quiet but responsive, dehydration was assessed at 5% to 7%, and heart rate was slightly elevated at 180 beats/minute. All other findings were normal.

Diagnostics. The abnormal results of CBC, serum chemistry, and urinalysis are given in the Table.

Ask yourself...

Which of the following is the most appropriate next step toward a definitive diagnosis?A. Do ultrasound-guided renal biopsy.B. Run an ethylene glycol test.C. Take abdominal radiographs.D. Determine the species of plant leaf observed in vomitus.E. Evaluate response to treatment.

Correct Answer: DDetermine the species of plant leaf observed in vomitus.

After further questioning, the owners reported that they had received a lily as a gift 2 days before and that the leaf in the vomitus was from the lily. Members of the Lilium (true lilies) and Hemerocallis (day lilies) genera can cause renal failure and death when ingested by cats. Lilies cause acute renal tubular necrosis without damaging the basement membrane. All parts of the plant are considered toxic. Only small amounts are required-less than one leaf or a small amount of pollen-to cause clinical signs. The results of serum chemistry and urinalysis are generally similar to those of other causes of renal failure, with the exception of the disproportionate increase in creatinine compared with BUN concentrations.

Treatment goals include successful decontamination and fluid therapy. In cats that have already begun to vomit, administration of activated charcoal with a cathartic is advised to minimize further absorption of the plant toxins. Before activated charcoal, administration of an antiemetic is recommended, and the cat should be carefully monitored to reduce risk for aspiration. If the cat has been observed to ingest plant material and has not yet vomited, induction of emesis is appropriate to begin decontamination. Fluid diuresis at twice maintenance rates for at least 48 hours is recommended to maintain urine flow and prevent obstruction of the renal tubules from sloughing epithelial cells. Cats that become anuric have a poorer prognosis, although in some cases renal function has been restored after long-term peritoneal dialysis.

This cat received twice maintenance fluid diuresis for 72 hours. During that time, the renal values gradually returned to normal and the cat maintained good urine output. The cat also stopped vomiting, began to eat, and regained normal mentation. She was weaned off fluids over a 48-hour period, and the renal values remained normal. The cat was discharged. Blood analysis was repeated 2 weeks later, and all values remained normal.

Take-Home MessageIngestion of even small amounts of true lilies or day lilies should be considered potentially toxic in cats.