Toxicology case: Jatropha multifida toxicosis in a dog

A 4-year old 50-lb (22.7-kg) neutered male standard poodle was presented to an emergency clinic for evaluation of severe vomiting, anorexia, and lethargy that had progressively worsened over the preceding two days. The owner observed that the initial vomitus contained between 10 to 20 intact as well as chewed sections of an unknown type of large seed.

Initial conservative treatment at the pet's regular veterinarian included famotidine (20 mg orally every 24 hours), metronidazole (250 mg orally every 24 hours), sucralfate (1 g orally every 12 hours), and a bland diet. After eight hours, these treatments had failed to control the clinical signs, so the pet was referred to an emergency clinic for further diagnostic testing and treatment.

EMERGENCY ASSESSMENT

Upon arrival to the emergency clinic, the dog was lethargic and moderately dehydrated (estimated 7% to 8%). Jaundice was also noted by the emergency clinician. The jaundice as well as the previously noted emesis of an unknown seed led to a suspicion of sago palm (Cycas revoluta) toxicosis. While the dog was being treated, the owner was sent home to see if the dog could have had access to a sago palm and, if so, if the seeds matched the ones it had vomited earlier.

The owner did not find a sago palm on his property but did find several seeds in the yard that matched the ones found in the vomitus. Upon the advice of the emergency clinician, the owner contacted the ASPCA Animal Poison Control Center (APCC) for help identifying the seed and making recommendations for treatment. The owner provided pictures of the suspected tree (Figures 1 & 2), which allowed the identification and confirmation of Jatropha multifida (commonly known as physic nut, coral plant, or coral bush) as the source of the seeds.

1 & 2: The dog’s owner took photos of the suspicious seeds and tree, later confirmed as Jatropha multifida. [Editors' note: Whoops! These are actually photos of Jatropha podagrica, not Jatropha multifida. The two species look a lot alike, and both have similar toxicology profiles. In this case, the owner was found to have both species of Jatropha in his yard. Jatropha multifida seeds were determined to be the mostly likely cause of the toxicosis in this dog.]

CASE MANAGEMENT

Initial patient management included administration of intravenous fluids (lactated Ringer's solution 100 ml/hr following a 250-ml bolus), antiemetics (maropitant 1 mg/kg subcutaneously every 24 hours), continuation of the gastrointestinal (GI) protectants famotidine and sucralfate (at previous dosages and intervals), and S-adenosylmethionine (SAMe; 450 mg orally every 24 hours). An ultrasonographic examination of the GI system showed no abnormalities other than possible mild generalized enlargement of the spleen.

Presenting serum chemistry profile results showed marked elevation in alkaline phosphatase (ALP) activity (4,600 μmol/L; normal = 0 to 212 μmol/L), gamma-glutamyltransferase (GGT) activity (24 μmol/L; normal = 1 to 6 μmol/L), and total bilirubin concentration (11.5 mg/dl; normal = 0 to 0.7 mg/dl) and a moderate elevation in alanine aminotransferase (ALT) activity (160 μmol/L; normal = 0 to 30 μmol/L). In addition, a moderate thrombocytopenia (41,000/μl; normal = 150,000 to 500,000/μl) was noted and confirmed by a blood smear. In light of the elevations in hepatic enzyme activities and thrombocytopenia, a coagulation profile (including prothrombin time, activated clotting time, and partial thromboplastin time) was performed, and the results were normal.

Initial care was continued with the addition of 5% dextrose to the lactated Ringer's solution in order to prevent further hepatic injury. The hepatoprotective effects of dextrose supplementation are via its inhibition of gluconeogenesis. This inhibition maintains hepatic glycogen stores, which are known to protect hepatocytes from cellular damage.1

After 24 hours of hospitalization, the GI signs resolved, but the ALP activity continued to elevate from 4,600 to 7,000 μmol/L, as did the ALT activity from 160 to 465 μmol/L. The previously noted treatment was continued overnight.

After 48 hours, the dog's condition continued to improve with the return of its appetite. Repeated serum chemistry profile results showed further increases in ALT (from 465 to 586 μmol/L) and GGT (from 24 to 57 μmol/L) activities, while the ALP activity remained elevated and the total bilirubin concentration decreased (from 11.5 to 6.4 mg/dl).

Because of financial constraints, the pet was discharged to the owner 72 hours after exposure with fluids for subcutaneous administration (200 ml lactated Ringer's solution b.i.d. for four days), GI protectants (famotidine and sucralfate at previously noted dosages for seven days), and SAMe (at previously noted dosage for 10 days). A hepatic-specific diet was recommended but never administered because of pet aversion.

FOLLOW-UP

Two days after discharge (five days after exposure) the ALT activity increased from 969 to 1,095 μmol/L, but the ALP activity decreased (from 7,000 to 3,600 μmol/L). Other laboratory values were normal. A follow-up phone consultation with the owner 10 months after exposure showed that while the dog was clinically normal within the week after discharge, the hepatic enzyme activities took three weeks to return to within reference ranges.

DISCUSSION

Jatropha multifida is native to tropical America but is widely cultivated throughout the world, including Australia and Africa. It is a common ornamental species in Florida.2 The plant's fruit is a yellow-green capsule that is slightly more than an inch in length.2 Each capsule contains three seeds on average. The meat of the seeds is white in color and oily in texture, though it is generally considered highly palatable.2

Toxicity

The seeds of J. multifida are known to contain two main toxins that could lead to clinical signs after ingestion. The first type includes a variety of diterpenoid esters, including the tigliane-type, such as citlalitrione, curcusones, and riolozatrione.3 These toxins have been shown by in vitro studies to have the potential to cause cardiac and respiratory depression. The second toxin types are known as toxalbumins, which are proteins known to inhibit protein synthesis, similar to the effects of ricin.2 Despite the presence of these toxins, most cases with exposure to the seeds of Jatropha species are characterized by GI signs only.

Previous Jatropha species ingestions reported to the ASPCA Animal Poison Control Center (APCC) over a 10-year period (2002-2012) showed one other case (out of 42 total exposures) in which hepatic enzyme activities showed marked elevation.4

Transient subclinical elevations in hepatic enzyme activities in people are commonly noted after exposure to Jatropha species, rarely requiring treatment.5,6 As is true with other toxalbumin-containing seeds such as castor beans (Ricinus communis), it appears that mastication is required for release of the toxin and development of subsequent clinical signs.6 It is likely that a marked amount of toxin is released only when the seeds are crushed or broken, leading to GI signs and hepatic damage. When the seeds are not broken, clinical signs are limited to GI upset.

Diagnosis and treatment

A tentative diagnosis of J. multifida toxicosis is based on the presence of seeds in the vomitus or in the stool combined with characteristic GI clinical signs.

Decontaminate suspected cases aggressively, and monitor the patients for appearance of clinical signs and indicators of hepatic injury. Recent ingestions should be initially decontaminated with the induction of emesis with 3% hydrogen peroxide (1 ml/kg orally, not to exceed 45 ml per dose)7 or apomorphine (0.03 mg/kg intravenously or in the conjunctival sac),7 with subsequent administration of a single dose of activated charcoal (1 to 3 g/kg orally with a cathartic such as sorbitol).7 Use of a warm tap water enema (5 to 10 ml/kg) could help facilitate removal of the seeds, provided that diarrhea is not already present.

Symptomatic and supportive control of GI signs, including antiemetics (maropitant 1 mg/kg subcutaneously every 24 hours),7 GI protectants (omeprazole 0.5 to 1 mg/kg orally every 24 hours, sucralfate 0.5 to 1 g orally every eight to 24 hours),7 bland diets, and fluids as necessary to prevent dehydration is warranted. Additional use of hepatic protectants, such as SAMe, in cases of large ingestions may also prove beneficial in preventing hepatic damage.1

Monitoring

Serum chemistry profiles should be evaluated at presentation, with reevaluations at 24 to 48 hours, depending on the development and severity of clinical signs. If severe signs develop, then daily monitoring is indicated.

Differential diagnosis

When presented with a possible case of Jatropha species toxicosis, rule out other hepatotoxic agents such as sago palm, mushrooms (Amanita species, Gyromitra species), nonsteroidal anti-inflammatory drugs, and xylitol as well as metabolic and infectious causes.

Conclusion and clinical relevance

Although likely to only result in GI disturbances, the potential for marked hepatic injury after ingestion of J. multifida seeds necessitates monitoring of hepatic enzyme activities as well as consideration for the use of hepatic protective agents. Additional supportive and symptomatic care (e.g. intravenous fluids) should be provided as necessary.

Jarrod Butler, DVM, ASPCA Animal Poison Control Center, 1717 S. Philo Road, Suite 36, Urbana, IL 61801.

To view the references for this article, visit dvm360.com/JatrophaRefs.

To learn more about sago palm toxicosis, visit dvm360.com/SagoTox.

About the ASPCA Animal Poison Control Center (APCC)

The ASPCA Animal Poison Control Center (APCC) is a 24-hour animal emergency consultation service that provides treatment and diagnostic recommendations to animal owners and veterinarians regarding animal poisoning cases 24 hours a day, 7 days a week, 365 days a year. Since 1978, the veterinary staff at the APCC has experience of handling more than 2 million animal poisoning cases involving pesticides, herbicides, plants, human and animal drugs, heavy metals, and many other potentially hazardous chemicals. A $65 consultation fee may apply. This includes follow-up consultations for the duration of the case. If you think your animal may have ingested a potentially poisonous substance, call (888) 426-4435. Additional information can be found online at www.aspca.org/apcc.