Cynthia R. Biron, RDH
Today we are seeing more patients who are medically compromised, and are taking several drugs. There are so many drugs available for the treatment of various conditions and disease processes that prioritizing on the greatest problem in the patient`s medical history requires a great deal of analytical thinking. Phone calls to several medical specialists may be required before dental treatment can be provided for a patient.
Case
The following case shows the medical history of a patient who has hepatitis C. The patient, Rodney Jacobs (name has been changed), took several prescribed medications for a myriad of medical problems. Rodney presented in a dental clinic as a new patient seeking routine dental care. It had been 12 years since his last dental appointment and 10 years since he learned that he had hepatitis C, when he was diagnosed with cirrhosis of the liver. Other conditions that Rodney had included high blood pressure, hypothyroidism and alopecia (hair loss). Medications Rodney had been taking were Hyoscamine Sulfate, Monopril, Synthroid, Lasix and Cortisone injections twice a month. Vital signs were:
Blood Pressure: 160/110
Pulse: 68
Respirations: 20
Height: 5`8"
Weight: 195 lbs.
History of hepatitis C
For several reasons, Rodney should not be treated without a consult from his physician. Hepatitis C is a finding that raises a red flag for all health-care workers due to the risks of exposure. However, universal precautions are taken with every patient, many of whom are carriers of bloodborne pathogens without patient or clinician having knowledge of the presence of the virus in the patient`s blood. So our first concern relative to the hepatitis C is Rodney`s liver function. He takes Hyoscamine Sulfate for gastrointestinal disorders related to cirrhosis of the liver. The liver condition is a finding that requires a consultation, as drugs and local anesthesia used in dentistry cannot be biotransferased in the liver of some patients with cirrhosis. If the liver cannot break down the drugs, a toxic blood level of the drugs can occur. Invasive dental procedures can cause a bacteremia, and patients with a liver disorder also may be immunocompromised. The liver problems also may cause impaired wound healing.
History of hypertension
Rodney`s blood pressure is too high, in spite of his faithfulness in taking the antihypertensive, Monopril, an Angiotensin-Converting Enzyme-Inhibitor (ACE Inhibitor). He has been taking Lasix (a potent diuretic), which also reduces blood pressure. Rodney should be referred back to his physician for a re-evaluation of his blood pressure.
History of hypothyroidism
Rodney takes Synthroid, a synthetic form of thyroid hormone for his hypothyroidism. There are no contraindications to dental treatment for patients taking Synthroid. Rodney is significantly overweight, and there is some concern as to whether the Synthroid regimen Rodney is taking is really controlling his hypothyroidism. A hypothyroid patient can be very sensitive to CNS depressants. Antianxiety agents, pain medications and nitrous oxide are classified as CNS depressant drugs, which commonly are used in dentistry. Before Rodney can be given any CNS depressants, a consultation with Rodney`s physician on the risk factors of hypothyroidism must be considered.
History of Cortisone
Rodney has received two Cortisone injections per month for the last four months for rash-associated alopecia. A consult is necessary to determine the risk factors associated with exogenous corticosteroid therapy. The anti-inflammatory properties of Cortisone places a patient at risk for infection and, on very rare occasions, adrenal insufficiency. Rodney said he has been seeing a dermatologist for the rash on his scalp, which has caused alopecia. A prophylactic antibiotic may be necessary before scaling and other invasive dental procedures.
Concerns about hepatitis C
Having researched all risk factors for providing patient care, we are left with our ultimate concern about the increased incidence of hepatitis C (formerly known as hepatitis non-A non-B), the patient`s prognosis and the disease transmission. Yes, we use universal precautions to prevent transmission of the disease, but we need to know more about the disease and the probability of contracting the disease from the patient. Our first place to look for answers is the Internet, the Center on Disease Control (CDC/OC/MEDIA: Facts About Hepatitis A and C) or (http://www.cdc.gov/od/oc/media/fact/henac.htm).
The latest facts on hepatitis C include the symptoms, which usually include some degree of jaundice, a characteristic fatigue associated with any type of hepatitis, a loss of appetite, periodic nausea and vomiting. There are an astounding 35,000 to 180,000 total infections occurring yearly in the United States; and 8,000 to 10,000 of those individuals infected with the virus will die this year. More than 85 percent of the infected population will develop chronic infection, resulting in chronic hepatitis C infection in 3.9 million Americans. With these statistics, it is easy to see that we are treating patients who have hepatitis C, and probably they, as well as we, do not know they have the virus. From 24,000 to 126,000 patients with hepatitis C will develop chronic liver disease each year. Hepatitis C may be transmitted by blood, body fluids and sexual contact.
In the United States from 1990 to 1993, 55 percent of the cases of Acute HCV were accounted for through the following risk factors: injecting drug use (38 percent), sexual or household exposure (10 percent), percutaneous exposures such as needlesticks or blood transfusions (4 percent), occupational exposure to blood (2 percent), hemodialysis (1 percent). More than 50 percent of the individuals questioned in this study reported that they were involved in high-risk behaviors such as illegal drug use, having sexually transmitted diseases, a sex partner who injected drugs and other transmissible infectious diseases.
Preventing the transmission of hepatitis C
Universal precautions utilized for all dental treatments serve to provide the only protection for the clinicians, dental staff and all patients. Unlike hepatitis B, hepatitis C is not preventable by the hepatitis B Vaccine (Recombivax HB, Engerix-B). There is no vaccine for hepatitis C.
Postexposure prophylaxis for hepatitis C
There is no postexposure prophylaxis available for hepatitis C. The administration of immune globulin (Ig) is not recommended, as in February of 1994 the Immunization Practices Advisory Committee of the CDC declared that data do not support the use of IG for prophylaxis of hepatitis C. With regard to postexposure testing, the data for predicting the probability of disease transmission from needlesticks or other percutaneous exposures, such as instrument sticks, are limited to nonexistent. Therefore, it is difficult to predict a health-care worker`s probability of developing HVC should he or she experience a percutaneous exposure.
The available testing methods are also are limited. The commercially manufactured enzyme immunoassays (EIAs) that detect anti-HCV may have a prolonged exposure and seroconversion. A seroconversion is the development of evidence of antibody response to an antigen, in this case, hepatitis C antigen. The average time period for seroconversion is 8-10 weeks. Of great concern is the fact that the rate of false positivity for anti-HCV is high. Validity can only be ascertained by repeated tests. Some 5-10 percent of infections will not be detected unless a polymerase chain reaction (PCR) test is used to detect the HCV RNA. This type of test will cost at least $200 and must be repeated for validity.
The cause of many false-positive and false-negative results may be from improper handling of blood samples. Some hospitals and institutions have protocols for postexposure that include baseline testing and six-months follow- up testing. Costs of the tests may be the responsibility of the individual who has been exposed. If we do fall in the 2-4 percent category along with other percutaneous exposures including blood transfusions, our risk factor seems to be rather low. Whether we want to get into extensive testing, if we are exposed, may be dependent on many factors. We certainly wouldn`t want to infect those people in our lives with whom we are intimately involved. If you have been exposed and are a known carrier, must you give up your career for fear of exposing a patient? No, not at all. Must you tell your future employers or patients? No, not at all. There are no restrictions for health-care professionals who have hepatitis C, and the risk of transmission to a patient is extremely low. If universal precautions are employed, the risk factors are most probably non-existent. If a patient should contract the disease, there are no serologic assays that determine how he or she was infected, so the data that exists for the low incidence of patients who contracted the disease and happened to be treated by infected clinicians, may, in fact, be coincidence.
Treatment for hepatitis C
There is no specific treatment for hepatitis C. Chronic liver disease has been treated with Recombinant Interferon Alpha-2b (Intron A/Schering) with some effectiveness according to a study conducted at the University of Florida, College of Medicine by virologists J. Lau and G. Davis. "In the clinical studies, the Interferon returned serum aminotransferase levels in more than 27 percent, 33 percent and 41 percent of patients receiving, respectively, 1, 2 and 3 million units, compared with 2.6 percent in untreated patients (study results pooled). However, reduction in levels occurred in at least half the responders after Interferon Alpha-2b treatment was discontinued." Oral Ribavarin is another drug being evaluated for treatment of HCV. More research needs to be conducted to determine the effectiveness of the many drugs in clinical trials.
We know that there are many occupational hazards associated with our profession of dental hygiene, and we are taking all the precautions available. Our knowledge of the likeliness of contracting the diseases, coupled with a respect for the necessary precautions, enable us to confidently provide quality patient-care with a high degree of safety for ourselves and our patients. We pride ourselves with being well informed about these concerns and our abilities to properly inform our patients.
References
- Center for Disease Control: CDC/OC/MEDIA: Facts About Hepatitis A and C, July 25, 1997.
- Center for Disease Control: Hepatitis Surveillance, Report Number 56, April 1996.
- Hernandez MD, Bruguera M, Puyuelo T, Barrera JM, Sanchez Tapias JM, Rodes J. Risk of needle-stick injuries in the transmission of hepatitis C virus in hospital personnel. J Hepatol 1992; 16:56-58
- Zuckerman J, Clewley G, Griffiths P, Cockcroft A. Prevalence of hepatitis C antibodies in clinical health-care workers. Lancet 1994;343:1618-1620.
- Krawczynski K, Alter MJ, Tankersley DL, et al. Effect of immune globulin on the prevention of experimental hepatitis C virus infection. J Infect Dis 1996, in press.
- Alter MJ, Gerety RJ, Smallwood L, et al. Sporadic non-A, non-B hepatitis: frequency and epidemiology in an urban United States population.; J Infec Dis 1982; 145:886-893.
- Esteban JI, Gomez J, Martell M, et al. Repeated transmission of HCV from surgeon to patients during cardiac surgery (abstract). Hepatology 1995;22:347A
- Fried MW, Hoofnagle, JH. Therapy of hepatitis C. Semin Liver Dis 1995: 15:82-91.
- Wynn RL, et al. Drug Information Handbook in Dentistry. 3rd ed. 1997-1998 Lexi-Comp Inc., Hudson (Cleveland)
Cynthia R. Biron, RDH, is chair of the dental hygiene program at the Tallahassee Community College. She also is a certified emergency medical technician.
