How Much Does a TB Skin Test Cost? A Comprehensive Guide

How Much Is A Tb Skin Test? Understanding the cost of a TB skin test, also known as the Mantoux tuberculin skin test, involves various factors like location, healthcare provider, and insurance coverage. HOW.EDU.VN provides expert insights into navigating these costs and understanding the importance of this essential screening tool. Explore the details of TB screening costs, local health department options, and affordable screening solutions.

1. Understanding the TB Skin Test

The Tuberculin Skin Test (TST), or Mantoux test, is a common method used to determine if someone has been infected with Mycobacterium tuberculosis, the bacteria that causes tuberculosis (TB). This test involves injecting a small amount of tuberculin purified protein derivative (PPD) under the skin on the forearm.

1.1 How the TB Skin Test Works

The PPD is a standardized solution derived from tuberculin, designed to elicit an immune response in individuals previously exposed to TB bacteria.

Typically, if a person has been infected with TB bacteria, the immune system will recognize the PPD. This is because PPD is derived from proteins that M. tuberculosis excretes when grown in specialized media under standardized conditions. The solution is carefully diluted to meet FDA-approved standards for concentration and potency.

It usually takes between 2 to 8 weeks after the initial TB infection for the immune system to react to PPD, which is when the infection can be detected by the TB skin test.

1.2 Advantages and Disadvantages of the TB Skin Test

1.2.1 Advantages

• Simplicity: The test is simple to perform, requiring no complex laboratory equipment.
• Cost-Effective: Generally, it is a low-cost screening option.
• Accessibility: No need for phlebotomy (drawing blood).
• Established Standards: Well-established criteria for TB skin test conversions.
• Research Legacy: Benefits from decades of clinical and epidemiological research.

1.2.2 Disadvantages

• Professional Administration: Requires trained healthcare personnel to administer and interpret the results.
• Storage Requirements: Requires proper refrigeration and inventory management of the skin test solution.
• Multiple Visits: Requires at least two patient visits – one for administration and another for reading the results.
• False Positives: Previous BCG vaccination or infection with nontuberculous mycobacteria can lead to false-positive results.
• False Negatives: Concurrent infections or a weakened immune system can cause false-negative results.
• Rare Adverse Effects: Although rare, adverse reactions can occur.
• Booster Phenomenon: The test can sometimes cause a booster phenomenon, complicating interpretation.
• Subjectivity: Potential for bias and errors in placement and reading of the skin test.

1.3 Who Can Administer and Read TB Skin Tests?

The TB skin test should be administered and read by a healthcare provider who has been specifically trained to perform these tasks. To find out who is authorized to administer and read TB skin tests in your state, consult your local public health authorities.

1.4 TB Skin Test Training Materials

Training is crucial for healthcare providers to become proficient in both administering and interpreting the TB skin test. The CDC offers free training materials, including fact sheets, wall charts, and videos, which can be downloaded or ordered.

2. Factors Influencing the Cost of a TB Skin Test

The cost of a TB skin test can vary significantly based on several key factors. Understanding these elements can help you anticipate and manage the expenses associated with this essential health screening.

2.1 Location

Geographic location plays a crucial role in determining the price of a TB skin test. Prices can differ between states, cities, and even neighborhoods due to variations in healthcare costs, local regulations, and the availability of services.

• Urban vs. Rural Areas: Urban centers with a higher cost of living often have more expensive healthcare services compared to rural areas. The overhead costs for clinics and healthcare providers in cities are generally higher, leading to increased prices for medical services, including TB skin tests.
• Regional Differences: Different regions may have varying healthcare policies and economic conditions that impact the pricing of medical tests. For example, states with higher minimum wages or stricter healthcare regulations might see higher prices for TB skin tests.

2.2 Healthcare Provider

The type of healthcare provider you choose can significantly influence the cost of a TB skin test. Different providers have varying pricing structures based on their operational costs, specialization, and the services they offer.

• Private Clinics: Private clinics often have higher prices compared to public health departments or community health centers. These clinics may offer more personalized care, shorter wait times, and a wider range of services, which can contribute to the higher cost.
• Hospitals: Getting a TB skin test at a hospital can be more expensive due to the higher overhead costs associated with hospital facilities and staffing. Emergency rooms, in particular, should be avoided for routine TB testing due to their high costs.
• Public Health Departments: Public health departments are often the most affordable option for TB skin tests. These departments are government-funded and typically offer TB testing at a lower cost or even for free, especially for individuals who meet certain risk criteria.
• Community Health Centers: Community health centers are non-profit organizations that provide healthcare services to underserved populations. They often offer TB skin tests on a sliding fee scale, making them an accessible and affordable option for low-income individuals.
• Urgent Care Centers: Urgent care centers can be a convenient option for TB skin tests, but they may be more expensive than public health departments or community health centers. However, they often offer extended hours and walk-in appointments, which can be beneficial for those with busy schedules.

2.3 Insurance Coverage

Health insurance coverage can greatly reduce the out-of-pocket expenses for a TB skin test. However, the extent of coverage depends on your specific insurance plan, including the type of plan, deductible, co-pay, and co-insurance.

• Types of Insurance Plans:
  • HMO (Health Maintenance Organization): HMO plans typically require you to choose a primary care physician (PCP) who coordinates your care. You may need a referral from your PCP to get a TB skin test covered.
  • PPO (Preferred Provider Organization): PPO plans allow you to see any healthcare provider without a referral, but you’ll pay less if you stay within the plan’s network.
  • EPO (Exclusive Provider Organization): EPO plans are similar to HMOs but don’t require a PCP. However, you must stay within the plan’s network to have your TB skin test covered.
  • POS (Point of Service): POS plans combine features of HMOs and PPOs. You can see out-of-network providers, but you’ll pay more unless you get a referral from your PCP.
• Deductible: Your deductible is the amount you must pay out-of-pocket before your insurance begins to cover costs. If your deductible is high, you may need to pay the full cost of the TB skin test until you meet your deductible.
• Co-Pay and Co-Insurance:
  • Co-Pay: A co-pay is a fixed amount you pay for a healthcare service, such as a TB skin test.
  • Co-Insurance: Co-insurance is a percentage of the cost you pay after you meet your deductible. For example, if your co-insurance is 20%, you’ll pay 20% of the cost of the TB skin test, and your insurance will cover the remaining 80%.
• Preventive Care Coverage: Many insurance plans cover preventive services, including TB screening, without cost-sharing. However, this may depend on your risk factors and whether the TB skin test is considered medically necessary. Check with your insurance provider to understand your coverage for TB testing.

2.4 Additional Costs

Besides the direct cost of the TB skin test, there may be additional expenses to consider, such as consultation fees, follow-up visits, and the cost of treating latent TB infection if the test is positive.

• Consultation Fees: Some healthcare providers may charge a consultation fee for the initial visit to discuss your risk factors and determine if a TB skin test is necessary.
• Follow-Up Visits: The TB skin test requires two visits: one to administer the test and another to read the results. Each visit may incur a separate charge.
• Treatment Costs: If the TB skin test is positive, you’ll need further evaluation to determine if you have latent TB infection or active TB disease. Treatment for latent TB infection typically involves taking medication for several months, which can incur additional costs. Active TB disease requires a more intensive treatment regimen, including multiple medications and close monitoring.

2.5 Cost Without Insurance

For individuals without health insurance, the cost of a TB skin test can be a significant concern. The out-of-pocket expenses can vary widely depending on the factors mentioned above.

• Average Costs: On average, a TB skin test can cost between $20 and $100 or more without insurance. However, this is just an estimate, and the actual cost may be higher or lower depending on your location and the healthcare provider you choose.
• Negotiating Prices: If you don’t have insurance, don’t hesitate to negotiate the price of the TB skin test with the healthcare provider. Many providers offer discounts for uninsured patients or allow you to pay in installments.
• Financial Assistance Programs: Explore financial assistance programs offered by hospitals, community health centers, and non-profit organizations. These programs can help you cover the cost of the TB skin test and other healthcare services.

Understanding these factors can help you make informed decisions about where to get a TB skin test and how to manage the associated costs. Whether you have insurance or not, there are options available to make TB testing accessible and affordable.

3. Average Cost of a TB Skin Test

The price of a TB skin test is not uniform and can vary significantly depending on the provider and location. Below, we break down the typical costs associated with this essential screening.

3.1 Cost Breakdown by Provider Type

Different types of healthcare providers have varying pricing structures for TB skin tests. Understanding these differences can help you choose the most cost-effective option for your needs.

• Public Health Departments: Public health departments are often the most affordable option for TB skin tests. These departments are government-funded and typically offer TB testing at a lower cost or even for free, especially for individuals who meet certain risk criteria.
  • Average Cost: $0 to $30
  • Benefits: Low or no cost, focus on public health, may offer additional services like counseling and education.
• Community Health Centers: Community health centers are non-profit organizations that provide healthcare services to underserved populations. They often offer TB skin tests on a sliding fee scale, making them an accessible and affordable option for low-income individuals.
  • Average Cost: $10 to $50 (sliding fee scale available)
  • Benefits: Affordable, accessible, culturally sensitive care, focus on community health.
• Private Clinics: Private clinics often have higher prices compared to public health departments or community health centers. These clinics may offer more personalized care, shorter wait times, and a wider range of services, which can contribute to the higher cost.
  • Average Cost: $30 to $100
  • Benefits: Personalized care, shorter wait times, comprehensive services, convenient locations.
• Urgent Care Centers: Urgent care centers can be a convenient option for TB skin tests, but they may be more expensive than public health departments or community health centers. However, they often offer extended hours and walk-in appointments, which can be beneficial for those with busy schedules.
  • Average Cost: $50 to $150
  • Benefits: Extended hours, walk-in appointments, convenient for immediate needs, can handle minor illnesses and injuries.
• Hospitals: Getting a TB skin test at a hospital can be more expensive due to the higher overhead costs associated with hospital facilities and staffing. Emergency rooms, in particular, should be avoided for routine TB testing due to their high costs.
  • Average Cost: $100 to $300
  • Benefits: Comprehensive medical services, advanced diagnostic capabilities, access to specialists, 24/7 availability.

3.2 Regional Price Variations

The cost of a TB skin test can vary significantly based on geographic location. Prices can differ between states, cities, and even neighborhoods due to variations in healthcare costs, local regulations, and the availability of services.

• Northeast: States in the Northeast, such as New York and Massachusetts, tend to have higher healthcare costs, including TB skin tests.
  • Average Cost: $50 to $200
  • Reasons: Higher cost of living, stricter healthcare regulations, higher demand for services.
• West Coast: The West Coast, particularly California, also has relatively high healthcare costs, impacting the price of TB skin tests.
  • Average Cost: $40 to $180
  • Reasons: High cost of living, large urban populations, diverse healthcare systems.
• Midwest: The Midwest generally has more moderate healthcare costs compared to the coasts, resulting in lower prices for TB skin tests.
  • Average Cost: $30 to $120
  • Reasons: Lower cost of living, more rural areas, less competition among providers.
• South: The South has a wide range of healthcare costs, with some states having very affordable TB skin tests and others being more expensive.
  • Average Cost: $20 to $150
  • Reasons: Varied economic conditions, diverse populations, different healthcare policies.

3.3 Factors Affecting Price

Several factors can influence the price of a TB skin test, including the healthcare setting, the provider’s fees, and the inclusion of additional services.

• Healthcare Setting:
  • Public vs. Private: Public health departments and community health centers typically offer lower prices due to government funding and non-profit status.
  • Specialized Clinics: Specialized clinics may charge more for TB skin tests due to their expertise and specialized services.
• Provider’s Fees:
  • Physician Fees: Private physicians and specialists may charge higher fees for their services, impacting the overall cost of the TB skin test.
  • Administrative Fees: Some providers may charge administrative fees for processing paperwork and managing patient records.
• Additional Services:
  • Consultation Fees: An initial consultation to discuss your risk factors and determine the need for a TB skin test may incur an additional charge.
  • Follow-Up Visits: The TB skin test requires a follow-up visit to read the results, which may incur a separate fee.

3.4 Ways to Reduce Costs

There are several strategies to reduce the cost of a TB skin test, including exploring low-cost options, checking for discounts and financial assistance programs, and utilizing insurance coverage.

• Low-Cost Options:
  • Public Health Departments: Contact your local public health department to inquire about low-cost or free TB skin tests.
  • Community Health Centers: Visit a community health center to access TB skin tests on a sliding fee scale based on your income.
• Discounts and Financial Assistance:
  • Uninsured Discounts: Ask healthcare providers if they offer discounts for uninsured patients or allow you to pay in installments.
  • Financial Assistance Programs: Explore financial assistance programs offered by hospitals, community health centers, and non-profit organizations.
• Insurance Coverage:
  • Check Your Plan: Contact your insurance provider to understand your coverage for TB skin tests, including deductibles, co-pays, and co-insurance.
  • Preventive Services: Inquire if your insurance plan covers TB screening as a preventive service without cost-sharing.

By understanding the average costs, regional variations, and factors affecting price, you can make informed decisions about where to get a TB skin test and how to manage the associated expenses. Whether you choose a public health department, a community health center, or a private clinic, there are options available to make TB testing accessible and affordable.

4. Where to Get a TB Skin Test

Knowing where to obtain a TB skin test is crucial for ensuring you receive timely and affordable screening. Various healthcare providers offer this service, each with its unique advantages and cost considerations.

4.1 Public Health Departments

Public health departments are often the most accessible and affordable option for TB skin tests.

• Services Offered:
  • TB skin tests
  • TB blood tests (IGRA)
  • Chest X-rays
  • Treatment for latent TB infection (LTBI)
  • Treatment for active TB disease
  • Contact tracing
  • TB education and prevention programs
• Benefits:
  • Low or no cost, especially for high-risk individuals
  • Focus on public health and disease prevention
  • Experienced staff with expertise in TB control
  • Connection to other public health services
• Considerations:
  • May have limited hours or require appointments
  • Eligibility criteria may apply
  • Services may be prioritized for high-risk groups

4.2 Community Health Centers

Community health centers provide comprehensive primary care services, including TB testing, to underserved communities.

• Services Offered:
  • TB skin tests
  • TB blood tests (IGRA)
  • Primary care services
  • Preventive care
  • Chronic disease management
  • Behavioral health services
  • Social services
• Benefits:
  • Affordable care on a sliding fee scale
  • Culturally sensitive and linguistically appropriate services
  • Comprehensive primary care services
  • Focus on community health and wellness
• Considerations:
  • May have limited availability or long wait times
  • Eligibility criteria may apply
  • Services may vary by location

4.3 Private Clinics and Physician’s Offices

Private clinics and physician’s offices offer TB skin tests as part of their general medical services.

• Services Offered:
  • TB skin tests
  • TB blood tests (IGRA)
  • General medical care
  • Preventive services
  • Diagnostic testing
  • Treatment for various illnesses and conditions
• Benefits:
  • Convenient and accessible care
  • Personalized attention from a primary care physician
  • Comprehensive medical services
  • Coordination of care with other specialists
• Considerations:
  • May be more expensive than public health departments or community health centers
  • Insurance coverage may vary
  • Appointment scheduling may be required

4.4 Urgent Care Centers

Urgent care centers provide immediate medical care for non-life-threatening illnesses and injuries, including TB skin tests.

• Services Offered:
  • TB skin tests
  • TB blood tests (IGRA)
  • Treatment for acute illnesses and injuries
  • Diagnostic testing
  • Vaccinations
  • Physical exams
• Benefits:
  • Walk-in appointments
  • Extended hours, including evenings and weekends
  • Convenient and accessible care
  • Shorter wait times compared to emergency rooms
• Considerations:
  • May be more expensive than public health departments or community health centers
  • Insurance coverage may vary
  • Not appropriate for serious or life-threatening conditions

4.5 School and Workplace Health Programs

Many schools and workplaces offer TB skin tests as part of their health programs, especially for individuals at higher risk of exposure.

• Services Offered:
  • TB skin tests
  • TB education and prevention materials
  • Referrals for follow-up care
• Benefits:
  • Convenient and accessible testing
  • May be offered at no cost to students or employees
  • Integration with other health programs
• Considerations:
  • Limited availability
  • Eligibility criteria may apply
  • May not offer comprehensive TB services

Choosing the right provider for your TB skin test depends on your individual needs, risk factors, and financial situation. Public health departments and community health centers are often the most affordable options, while private clinics and urgent care centers offer more convenient and comprehensive care. School and workplace health programs provide convenient testing for students and employees at higher risk of exposure.

5. Insurance Coverage for TB Skin Tests

Understanding how your health insurance covers TB skin tests is essential for managing your healthcare expenses. The extent of coverage can vary depending on your insurance plan, risk factors, and the medical necessity of the test.

5.1 Types of Insurance Plans

Different types of insurance plans have varying coverage policies for TB skin tests.

• HMO (Health Maintenance Organization): HMO plans typically require you to choose a primary care physician (PCP) who coordinates your care. You may need a referral from your PCP to get a TB skin test covered. HMO plans often have lower premiums and out-of-pocket costs but may have more restrictions on covered services and providers.
• PPO (Preferred Provider Organization): PPO plans allow you to see any healthcare provider without a referral, but you’ll pay less if you stay within the plan’s network. PPO plans offer more flexibility than HMO plans but typically have higher premiums and out-of-pocket costs.
• EPO (Exclusive Provider Organization): EPO plans are similar to HMOs but don’t require a PCP. However, you must stay within the plan’s network to have your TB skin test covered. EPO plans often have lower premiums than PPO plans but offer less flexibility.
• POS (Point of Service): POS plans combine features of HMOs and PPOs. You can see out-of-network providers, but you’ll pay more unless you get a referral from your PCP. POS plans offer a balance between flexibility and cost.

5.2 Factors Affecting Coverage

Several factors can influence whether your insurance plan covers a TB skin test.

• Medical Necessity:
  • Insurance plans typically cover TB skin tests when they are considered medically necessary. This means that your healthcare provider must determine that the test is needed to diagnose or rule out a medical condition.
  • Medical necessity is often based on risk factors, such as exposure to TB, living or working in a high-risk setting, or having certain medical conditions.
• Preventive Services:
  • Some insurance plans cover TB screening as a preventive service, especially for individuals at higher risk of TB.
  • The Affordable Care Act (ACA) requires most insurance plans to cover certain preventive services without cost-sharing, including TB screening for high-risk individuals.
• In-Network vs. Out-of-Network Providers:
  • Insurance plans typically have a network of healthcare providers they contract with to provide services to their members.
  • You’ll generally pay less if you see an in-network provider, as they have agreed to accept lower rates from the insurance plan.
  • Seeing an out-of-network provider can result in higher out-of-pocket costs, as the insurance plan may not cover the full cost of the service.

5.3 Understanding Your Policy

To understand your insurance coverage for TB skin tests, review your insurance policy documents and contact your insurance provider.

• Review Your Policy:
  • Read your insurance policy documents, including the summary of benefits and coverage, to understand your coverage for TB skin tests.
  • Pay attention to deductibles, co-pays, co-insurance, and any limitations or exclusions.
• Contact Your Insurance Provider:
  • Call your insurance provider’s customer service line to ask specific questions about your coverage for TB skin tests.
  • Ask about any requirements for prior authorization or referrals.
  • Confirm whether the TB skin test is covered as a preventive service or requires medical necessity.

5.4 Navigating Costs

Even with insurance coverage, you may still have out-of-pocket costs for TB skin tests.

• Deductibles:
  • Your deductible is the amount you must pay out-of-pocket before your insurance begins to cover costs.
  • If your deductible is high, you may need to pay the full cost of the TB skin test until you meet your deductible.
• Co-Pays:
  • A co-pay is a fixed amount you pay for a healthcare service, such as a TB skin test.
  • Your co-pay amount will depend on your insurance plan.
• Co-Insurance:
  • Co-insurance is a percentage of the cost you pay after you meet your deductible.
  • For example, if your co-insurance is 20%, you’ll pay 20% of the cost of the TB skin test, and your insurance will cover the remaining 80%.

By understanding your insurance coverage and navigating the associated costs, you can make informed decisions about where to get a TB skin test and how to manage your healthcare expenses. Whether you have an HMO, PPO, EPO, or POS plan, knowing your policy details and contacting your insurance provider can help you access affordable TB testing.

6. Free or Low-Cost TB Skin Test Options

For individuals without insurance or those with limited financial resources, several options are available to access TB skin tests at no cost or at a reduced price.

6.1 Public Health Departments

Public health departments are often the primary source for free or low-cost TB skin tests.

• Services Offered:
  • TB skin tests
  • TB blood tests (IGRA)
  • Chest X-rays
  • Treatment for latent TB infection (LTBI)
  • Treatment for active TB disease
  • Contact tracing
  • TB education and prevention programs
• Eligibility:
  • Services may be free or low-cost for individuals at higher risk of TB, such as:
    • Close contacts of people with active TB disease
    • People with HIV infection
    • People who inject drugs
    • People who live or work in congregate settings
    • People from countries where TB is common
• How to Access:
  • Contact your local or state health department to inquire about TB testing services.
  • Visit the health department’s website or call their information line for more details.
  • Be prepared to provide information about your risk factors and eligibility.

6.2 Community Health Centers

Community health centers provide affordable healthcare services to underserved communities, including TB skin tests.

• Services Offered:
  • TB skin tests
  • TB blood tests (IGRA)
  • Primary care services
  • Preventive care
  • Chronic disease management
  • Behavioral health services
  • Social services
• Eligibility:
  • Services are often provided on a sliding fee scale, based on income and family size.
  • Eligibility criteria may vary by location and funding source.
• How to Access:
  • Find a community health center near you by using the HRSA Health Center Locator.
  • Contact the health center to inquire about TB testing services and eligibility requirements.
  • Be prepared to provide documentation of your income and family size.

6.3 TB Screening Programs

Some cities, counties, or states have specific TB screening programs that offer free or low-cost testing to targeted populations.

• Examples:
  • School-based TB screening programs
  • Workplace TB screening programs
  • TB screening programs for immigrants and refugees
• Eligibility:
  • Eligibility criteria vary by program and may be based on age, occupation, immigration status, or other risk factors.
• How to Access:
  • Contact your local or state health department to inquire about TB screening programs in your area.
  • Check with schools, workplaces, or community organizations to see if they offer TB screening programs.
  • Be prepared to provide documentation of your eligibility.

6.4 Clinical Trials and Research Studies

Occasionally, clinical trials or research studies may offer free TB testing as part of their research efforts.

• Opportunities:
  • These opportunities may be available through universities, medical centers, or research institutions.
• Eligibility:
  • Eligibility criteria vary by study and may be based on age, health status, or other factors.
• How to Access:
  • Search for clinical trials or research studies related to TB testing on websites like ClinicalTrials.gov.
  • Contact the study investigators to inquire about eligibility and participation requirements.
  • Be aware of the potential risks and benefits of participating in a clinical trial.

6.5 Financial Assistance Programs

Various financial assistance programs may help cover the cost of TB testing for eligible individuals.

• Examples:
  • Medicaid
  • Children’s Health Insurance Program (CHIP)
  • Patient assistance programs offered by pharmaceutical companies
  • Charitable organizations
• Eligibility:
  • Eligibility criteria vary by program and may be based on income, age, health status, or other factors.
• How to Access:
  • Contact your local social services agency to inquire about Medicaid and CHIP eligibility.
  • Check with pharmaceutical companies or charitable organizations for patient assistance programs.
  • Be prepared to provide documentation of your income, health status, and other relevant information.

By exploring these free or low-cost options, individuals without insurance or those with limited financial resources can access the TB skin tests they need to protect their health and prevent the spread of TB. Public health departments, community health centers, TB screening programs, clinical trials, and financial assistance programs all offer valuable resources for affordable TB testing.

7. Understanding TB Test Results

Interpreting the results of a TB skin test requires careful assessment by a trained healthcare professional. The interpretation depends on the size of the induration (swelling) and the individual’s risk factors.

7.1 Reading the TB Skin Test

The TB skin test reaction should be read between 48 and 72 hours after administration by a healthcare worker trained to read TB skin results. If a patient has symptoms of TB disease, healthcare providers should not wait for TB skin test results before starting other diagnostic tests.

A patient who does not return within 72 hours will need to be rescheduled for another skin test. There is no risk associated with repeated TB skin test placements, unless a previous test was associated with a severe reaction.

The reaction should be measured in millimeters of the induration (firm swelling). Erythema (redness) should not be measured. The diameter of the indurated area should be measured across the forearm (perpendicular to the long axis).

7.2 Interpreting TB Skin Test Reactions

Skin test interpretation depends on two factors:

• Measurement in millimeters of the induration
• Person’s risk of TB infection or the risk of progression to TB disease if infected

7.3 Classification of TB Skin Test Reactions

7.3.1 An Induration of 5 or More Millimeters Is Considered Positive In:

• People with HIV
• Recent contacts of people with infectious TB disease
• People with chest x-ray findings suggestive of previous TB disease
• People with organ transplants
• Other immunosuppressed people (e.g., patients on prolonged therapy with corticosteroids equivalent to/greater than 15 mg per day of prednisone or those taking TNF-α antagonists)

7.3.2 An Induration of 10 or More Millimeters Is Considered Positive In:

• People born in countries where TB disease is common, including some countries in Asia, Africa, and Latin America
• People who misuse drugs and alcohol
• People who live or work in high-risk congregate settings (e.g., nursing homes, homeless shelters, or correctional facilities)
• Mycobacteriology laboratory workers
• People with certain medical conditions that place them at high risk for TB (e.g., silicosis, diabetes mellitus, severe kidney disease, certain types of cancer, or certain intestinal conditions)
• People with a low body weight (<90% of ideal body weight)
• Children younger than 5 years of age
• Infants, children, and adolescents exposed to adults in high-risk categories

7.3.3 An Induration of 15 or More Millimeters Is Considered Positive In:

• People with no known risk factors for TB

7.4 False-Positive Results

Some persons may have a positive result from a TB skin test even though they are not infected with TB bacteria. The causes of these false-positive results may include:

• Previous TB vaccination with the bacille Calmette Guérin (BCG) vaccine
• Infection with nontuberculosis mycobacteria (mycobacteria other than M. tuberculosis)
• Incorrect measurement or interpretation of reaction
• Incorrect antigen used

7.5 False-Negative Results

Some persons may have a negative result from a TB skin test even though they are infected with TB bacteria. The reasons for these false-negative results may include:

• Anergy (inability to react to a TB skin test because of a weakened immune system)
• Recent TB infection (within the past 8 to 10 weeks)
• Very young age (younger than 6 months)
• Recent live-virus vaccination, for example, measles or varicella
• Recent viral illness, particularly measles
• Incorrect method of giving the TB skin test
• Incorrect measuring or interpretation of TST reaction

Many life-threatening illnesses are associated with false-negative TB skin test results, such as protein-calorie malnutrition, advanced cancer, and TB disease itself, notably miliary TB and TB meningitis. If a false-negative TB skin test result is possible and TB is a concern in one of these situations, consult with a TB expert.

7.6 What to Do with Test Results

A person with a positive result from a TB skin test or symptoms of TB disease should be evaluated for TB disease. This includes performing:

• A chest radiograph and
• Appropriate bacteriologic examinations of sputum specimens

If latent TB infection is diagnosed, short and convenient treatment regimens are available. Treatment for latent TB infection is 90% effective for preventing the development of TB disease.

It is important to note that a negative TB skin test result does not exclude the diagnosis of TB disease, especially for patients with severe TB illness or HIV.

7.7 Reporting

All persons with clinically active or presumed TB disease should be reported to the local or state health department. Latent TB infection is reportable in some states and localities. For information on reporting requirements in your jurisdiction, consult your state TB program.

Understanding your TB test results is crucial for determining the appropriate course of action. If you have questions or concerns about your results, consult with your healthcare provider or a TB expert.

8. Benefits of Consulting with a TB Specialist via HOW.EDU.VN

Navigating the complexities of TB testing, understanding results, and determining the best course of action can be challenging. Consulting with a TB specialist through HOW.EDU.VN offers numerous benefits, providing expert guidance and personalized care.

8.1 Access to Top Experts

HOW.EDU.VN connects you with a network of over 100 renowned doctors and specialists from around the globe. These experts bring a wealth of knowledge and experience in diagnosing and treating TB, ensuring you receive the highest quality care.

8.2 Personalized Advice

Each individual’s situation is unique, and a one-size-fits-all approach is rarely effective. TB specialists on how.edu.vn provide personalized advice tailored to your specific risk factors, medical history, and test results. This ensures you receive the most appropriate and effective recommendations for your care.

8.3 Accurate Interpretation of Results

TB test results can be complex and may require careful interpretation. A TB specialist can accurately assess your results, taking into account factors such as the size of the induration, your risk factors, and any potential false-positive or false-negative results. This ensures you receive the correct diagnosis and appropriate treatment plan.

8.4 Comprehensive Evaluation

A TB specialist can conduct a comprehensive evaluation to determine the extent of your TB infection and rule out other potential causes of your symptoms. This may include ordering additional tests, such as chest X-rays or sputum cultures, to get a complete picture of your health.