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What’s Wrong With These Results?. Amitava Dasgupta, Ph.D, DABCC Professor of Pathology and Laboratory Medicine University of Texas-Houston Medical School. Alternative Medicine: Unexpected Lab Values.
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What’s Wrong With These Results? Amitava Dasgupta, Ph.D, DABCC Professor of Pathology and Laboratory Medicine University of Texas-Houston Medical School
Alternative Medicine: Unexpected Lab Values • Alternative medicines can interfere with clinical laboratory tests. This interference can be either positive or negative. • Alternative medicines can cause pharmacological effects or toxicity leading to unexpected lab values. • Alternative medicines may interact with therapeutic drugs. • Alternative medicines may be adulterated with Western drugs.
Alternative (Herbal) Medicines Interference in clinical laboratory testing due to direct interference with immunoassays.
Digoxin and Chan Su • One woman died after taking herbal tea containing Chan Su. • She never took digoxin or digitoxin. • Her apparent serum digoxin level was 4.9 ng/ml as measured by Fluorescence Polarization Immunoassay (Abbott Laboratories). Ko et al. West Med J 1996;43: 34-40
Chan Su • Chan Su is a traditional Chinese medicine prepared from skin glands of Chinese toads. It is used in treating heart diseases as Chan Su can stimulate myocardial contraction. • Chan Su contains bufalin which has structural similarity with digoxin. Bufalin is also toxic in animal models.
4.5 4 3.5 3 Pool 1FPIA Digoxin, ng/ml 2.5 Pool 1 MEIA 2 Pool 1 CLIA 1.5 1 0.5 0 Chan Su and Digoxin Assay CLIA: Chemiluminescent Assay (Bayer) 0 1.5 3.5 5 ml of Chan SU added to per ml of Digoxin pool Dasgupta et al. Am J Clin Pathol 2000;114: 174-179
3.5 3 2.5 2 Total Dig Free Dig Digoxin, ng/ml (FPIA) 1.5 1 0.5 0 0 1 2 3.5 5 Elimination of Interference • Chan Su interference eliminated by monitoring free digoxin ml of Chan Su added to per ml of digoxin pool
Digoxin and Herbal Medicines • Herbal medicines potentially interfering with digoxin immunoassays: • Chan Su • Lu-Shen-Wan • Danshen • Siberian and Asian Ginseng • Uzara Roots
Lu-Shen-Wan and Digoxin • Lu-Shen Wan is another Chinese medicine that contains bufalin. • Apparent digoxin activity of 0.88 ng/ml was reported in a volunteer who took one Lu-Shen-Wan Pill. • Lu-Shen-Wan interference: Eliminated by monitoring free digoxin Panesar NS. Clin Chem 1992;38: 2155-2156.
Siberain Ginseng and Digoxin • 74 year old male with a therapeutic digoxin level of 0.9-2.2 ng/ml for 10 years presented with a digoxin level of 5.2 ng/ml but showed no evidence of digoxin toxicity. • He was taking Siberian ginseng. After discontinuing Siberian ginseng his digoxin level returned to 0.9 ng/ml. McRae. Can Med Assoc J 1996;155:293-295
Siberian Ginseng: Our Experience • We tested three different Siberian ginseng for potential digoxin-like activity (Sundown, Root to Health, ZT Universal, Shanghai) • Analytical methods included: • FPIA, MEIA, EMIT 2000, Randox Digoxin, Beckman, chemiluminescent assay (Bayer). • Two preparations showed modest activity with the FPIA assay in vivo in mice after feeding with Siberian ginseng:
Asian Ginseng and Digoxin • Although both Asian and Siberian ginseng are imported from Asia, the two are chemically distinct: • Asian ginseng is prepared from Panax ginseng root • Siberain ginseng is prepared from Eleutherococcus senticosus. • One Asian ginseng (Song Shiu, Shanghai) out of the three products studied also showed modest interference with the FPIA digoxin after feeding in mice.
In Vivo Digoxin Activity in Mice • Herb FedBefore*After* • Asian Ginseng (Song) ND 0.68 • Asian Ginseng (Song) ND 0.50 • Siberian (ZT) ND 0.47 • Siberian (ZT) ND 0.32 • Siberian (Sundown) ND 0.26 • Siberian (Sundown) ND 0.21 *Fluorescence polarization assay (Abbott Laboratories) used
Ginsengs and Digoxin FPIA MEIA EMIT Randox Bayer
Dan Shen • Dan Shen is a traditional Chinese medicine prepared from roots of Salvia miltiorrhiza. • Dan Shen is used as a heart tonic. • More than 20 diterpene quinones known as “Tanshinones” have been isolated from Dan Shen. These compounds have structural similarity with digoxin.
Dan Shen and Digoxin Assay Digoxin, ng/ml Dasgupta et al Clin Chimica Acta 2002;317:231-234.
Dan Shen: In Vivo Results • Mouse # Apparent Digoxin, ng/ml Before 1h After 2h After 1 ND 0.20 0.46 2 ND 0.23 0.54 3 ND ND 0.26 4 ND ND 0.36 5 ND 0.20 0.45 6 ND 0.21 0.41 Dose:50 mg/Kg Dasgupta et al. Clin Chimica Acta2002;317:231-234.
Herbs and Digoxin assays. • Drug free serum supplemented with extract of different herbs. • Specimen FPIA Chan Su 4.9 ng/ml Lu-Shen-Wan 3.5 ng/ml Dan Shen 0.67 ng/ml Asian Ginseng 0.46 ng/ml Siberian Ginseng 0.32 ng/ml
Herbs and Digoxin Assay • HerbInterference Chan Su High Lu-Shen-Wan Moderate to High Dan Shen Moderate Asian Ginseng Low to Moderate Siberian Ginseng Low to Moderate
Elimination of Interference of Herbs in Digoxin Assays by Measuring Free Dig • HerbProtein BindingFree Digoxin • Chan Su 80-90% Yes • Dan Shen 70-80% Yes • Asian Ginseng 35-45%No • Siberian Ginseng 30-40%No Datta P, Dasgupta A. Ther Drug Monit (in press)
Elimination of Interference • EMIT 2000, Randox, Roche, Beckman and Bayer digoxin assays are free from interference by Dan Shen, Asian Ginseng and Siberian Ginseng. Only FPIA and MEIA are affected. • All assays except Bayer showed interference with Chan Su and Lu-Shen-Wan.
Alternative (Herbal) Medicine Unexpected test results due to pharmacological effect or toxicity directly related to the use of herbal medicine.
Herbs and Bilirubin Chan E. Biol Neonate 1993;63: 201-208.
Licorice (Glycyrrhizin) and Hypokalemia • Licorice usually induce hypertension. • However, 59 cases of licorice induced hypokalemic myopathy have been reported. • mean serum potassium - 1.98 mEq/L • total CK - 5385 U/L • plasma renin activity - 0.17 ng/ml/h (low) • 57 patients recovered after stopping licorice. Shintani et al. Eur Neurol 1992;32:44-51
Alternative (Herbal) Medicine Interactions between therapeutic drugs and herbals can lead to unexpected low drug levels in patients who were previously therapeutic.
Phenytoin, Phenobarbital and Herbs • Reduced seizure threshold • Reduced serum drug concentrations • EEvening primrose oil and borage oil both reduce seizure threshold of phenobarbital. • SShankhapushpi reduces seizure threshold of phenytoin. Fugh-Berman. Lancet 2000;355:134-138
St John’s Wort • A 32 year old female 3 year post kidney transplant showed a sub-therapeutic FK 506 (tacrolimus) level of 3.5 ng/ml. Her previous level was 8.3 ng/ml. Repeat testing with a fresh specimen next day (2.9 ng/ml) confirmed the previous result. • The patient had started taking St. John’s Wort; 300 mg capsules (0.03% hypericin, Nature’s Way) tid, ~8 weeks earlier.
Drug Interactions:St John’s Wort • Decreased serum drug concentrations • metabolism/transport: carbamazepine, cyclosporine, tacrolimus, HIV protease inhibitors (indinavir, nevirapine), simvastatin, theophylline, amitriptyline, ethinyl estradiol/desogestrel, digoxin, warfarin • decreased absorption: iron • Serotonin excess • SSRI’s (sertaline, paroxetine, nefazodone)
St John’s Wort CYP3A • hyperforin: pregnane X receptor ligand • species and organ specific • expression / activity • human: CYP3A4 (hepatic/intestinal) • rat: hepatic 3A2 (not intestinal 3A2) Hennessy. Br H Clin Pharmacol 2002;53:75-82 Durr. Clin Pharmacol Ther 2000;68:598-604 Roby. J Clin Psychopharmacol 2001;21:530-2
St John’s Wort P-glycoprotein/MDR1 • expression / activity • human: intestinal, hepatic, PBMC • rat: intestinal, PBMC (not hepatic) • enhanced drug efflux function • rhodamine 123 (PBMC’s) Hennessy. Br H Clin Pharmacol 2002;53:75-82 Durr. Clin Pharmacol Ther 2000;68:598-604 Roby. J Clin Psychopharmacol 2001;21:530-2
Oral Anticoagulants and Herbs • Ginseng, Danshen, Garlic, Ginkgo Biloba, Garlic, Ginger, Devil’s Claw, Red Clover and Horse-Chestnut inhibit platelet activity and interfere with extrinsic coagulation pathway. • These herbs should be avoided by all patients on warfarin therapy because of the possibility of excessive bleeding. Miller. Arch Int Med 1998;158:2200-2211
Herbs and Bleeding Ang-Lee and Yuan. JAMA 2001;286:209-216
Dan Shen and Warfarin • Mitral valvuloplasty was performed in a 48 year old female and her INR (international normalization ratio) was 1.5-3.0 (Warfarin dose: 2.5-3.5 mg). • She later came to ER. Her coagulation tests were abnormal (PT:>60 s, PTT >120 s, INR 5.62). She was taking Dan Shen causing over-anticoagulation. • Dan Shen was discontinued and her coagulation tests returned to normal again (INR:2.5).
Herbs and Surgery • Herbal ProductsEffects • Garlic, Ginkgo,Ginseng Bleeding • Ma Huang, Ephedra Cardiovascular • Ginseng Hypoglycemia • Kava-Kava, Valerian Prolonged Sedative effect of Anesthetics Ang-Lee et al JAMA 2001;286:208-216.
Alternative (Herbal) Medicine Unexpected results due to contamination of herbal products with Western medicines
Chinese Herbs Contaminated with Phenytoin • A patient never on phenytoin was admitted with a phenytoin level of 48.5 mg/ml. The patient was taking valproic acid and carbamazepine but never took phenytoin. However she was taking Chinese herbs (Jue Dian Shen Wan, Nang San Hao, etc). • Toxicological analysis confirmed the presence of phenytoin in these two preparations. Lau et al. Human Exp Toxicol 2000;19:385-386.
Herbal Medicine: Sulfonylurea • A 56 year old male presented to ER with severe hypoglycemia. Despite treatment, hypoglycemia did not improve. • Glucose: 37.8 mg/dL to 52.2 mg/dL. • He was taking Chinese medicine ZhenQi for Type II diabetes. • On analysis sulfonyluria (glibenclamide) was found in the herb. Goudie and Kaye MJA 2001;175:256-257.
Herb and Aplastic Anemia • A 12 year old boy was brought to ER for rash and gum bleeding. His hemoglobin was 8 gm/dL, platelet count 5000/ml. • His mother gave him Gan Mao Tong Pian for pain and fever a week ago. • Bone marrow biopsy confirmed aplastic anemia. • The boy survived after five months of therapy. • The herb contained phenylbutazone. Nelson et al Clin Toxicol 1995;33:467-470.
Herbs and Contamination • Western drugs like acetaminophen, caffeine, indomethecin, prednisolone, digoxin, phenytoin, phenylbutazone, and hypoglycemic agents have been found in herbal preparations. Huang Wf et al J Clin Pharmacol 1997;37:344-350
Conclusions • Unexpected digoxin results may be due to ingestion of Chinese herbs. Digoxin levels may be falsely high or low! • Unexpected low levels of therapeutic drugs may occur due to use of St. John’s Wort. • Patients taking drugs with narrow therapeutic ranges should not use any herbal products.
Conclusions • Abnormal coagulation tests may occur due to use of garlic, ginger, ginkgo etc. • Unexpected results may be related to contamination of herbals with Western medicines. Amitava Dasgupta: E-mail: Amitava.Dasgupta@uth.tmc.edu