Around 20 million Americans have thyroid disease, but 60% do not even know that they have it. The reason? They never get tested! Thyroid testing (including blood tests that measure the level of thyroid-stimulating hormones) is the most effective way to diagnose thyroid disorders. But is their billing as effective? Find out as we explore CPT code 84443 in detail.
This code is your key to collecting accurate reimbursements for performing TSH tests on insured patients.
CPT Code 84443 – Description
The Current Procedural Terminology (CPT) code 84443 can be found in the ‘Chemistry Procedures’ code range, which is maintained by the American Medical Association (AMA). It describes a thyroid-stimulating hormone (TSH) test to assess the patient’s thyroid function. The healthcare provider draws a blood sample from the patient’s vein and sends it to the laboratory for testing.
The lab technician measures the level of TSH in the blood and reports it in milli-international units per liter (μIU/mL) to determine whether the patient is suffering from hypothyroidism or hyperthyroidism. Note that when the level of TSH in the blood is high (above 4.2 μIU/mL), the patient is diagnosed with hypothyroidism. In contrast, when the levels of TSH fall in the bloodstream (below 0.4 μIU/mL), the patient is said to have hyperthyroidism.
Understanding TSH and Its Effects
But what is a thyroid-stimulating hormone, and why does its rise or fall in the bloodstream matter so much? Let’s explore this a little to understand the importance of a TSH lab test in relation to the patient’s well-being.
Thyroid-stimulating hormone, or thyrotropin, is produced inside the pituitary gland and released to regulate thyroid function. TSH stimulates the thyroid to produce and release triiodothyronine (T3) and thyroxine (T4), both of which are also hormones and help maintain the body’s metabolic rate. Besides regulating metabolism, T3 and T4 help control:
- Heart and digestive functions
- Bone health
- Brain development
- Muscle movement
Understanding Hyperthyroidism
Hyperthyroidism is a condition associated with an overactive thyroid gland. It means that the patient’s body is producing and releasing excess T3 and T4 hormones, and that is why the level of TSH in the blood is lower. Why? Because the T3 and T4 thyroid hormones suppress the production and release of TSH via a negative feedback loop.
Hyperthyroidism can cause a person to experience:
- Weight loss
- Rapid heartbeat
- Diarrhea
- Nervousness
- Vision changes
- Swelling or enlargement in the neck
- Irregular menstrual periods
Understanding Hypothyroidism
Conversely, hypothyroidism develops when the patient has an underactive thyroid gland. The levels of T3 and T4 plummet, which in turn signals the pituitary gland to produce more thyroid-stimulating hormone. Hence, the level of TSH in the blood rises. Hypothyroidism manifests itself as:
- Weight gain
- Fatigue
- Constipation
- Muscle weakness and numbness
- Feeling cold
- Depression
- Frequent and heavy menstruation
Scenarios Where CPT Code 84443 is Applicable
Now that we understand what a TSH blood test helps diagnose and its significance in ensuring the patient’s well-being, let’s discuss some clinical scenarios where this lab test will be necessary and can be accurately reported with CPT code 84443.
Assessing Thyroid Function During Pregnancy
Studies have shown that thyroid hormone production increases up to 50% during pregnancy. This is because, in the first few months of pregnancy, the fetus relies on the mother’s thyroid hormones for normal brain development. However, excessive thyroid hormone (T3 and T4) production, or hyperthyroidism, can complicate pregnancy. Therefore, TSH tests are performed on pregnant women to check the level of thyroid-stimulating hormone in the blood and detect hyperthyroidism early on.
Now, considering this fact, let’s assume that a 33-year-old pregnant woman (first trimester) visits her physician complaining of a rapid heartbeat, anxiety, heat intolerance, excessive sweating, and difficulty sleeping. The physician can also notice a visible bulge on the patient’s neck. He suspects that the patient has an overactive thyroid gland and suggests a blood test to diagnose or rule out hyperthyroidism. He draws a sample of blood from the woman’s arm vein and sends it to the lab for TSH testing. The lab analyst measures the TSH level in the blood, which comes out to be less than 0.18 μIU/mL. Hence, the patient is diagnosed with hyperthyroidism, and the lab analyst reports CPT code 84443 on the claim for the TSH pathology lab test.
Diagnosing Thyroid Disorders
We have mentioned in detail before that the primary function of a TSH lab test is to diagnose thyroid disorders like hypothyroidism and hyperthyroidism. So, let’s consider an example of that.
Suppose that a 20-year-old woman visits her physician complaining of weight gain (despite eating less), persistent fatigue, depression, and intolerance to cold temperatures. Moreover, she complains of heavy periods. After a brief physical exam, the physician orders a TSH blood test to check her thyroid function. The lab analyst performs the test, measures the level of TSH in her blood, which comes out to be over 4.3 μIU/mL, and uses CPT code 84443 for insurance billing. Later, at the physician’s office, she is diagnosed with hypothyroidism.
Monitoring the Effectiveness of Thyroid Treatment
Thyroid disorders can be effectively treated with medication. In the case of hypothyroidism, the most effective treatment is thyroid hormone replacement therapy. Physicians prescribe levothyroxine, a synthetic form of thyroxine (T4) hormone, to increase its levels and promote normal thyroid function.
Since thyroid hormone replacement therapy is needed for life and its dosage needs to be increased gradually over time, the physician will have to check TSH levels in the blood to monitor the effectiveness of the medication. So, a normal TSH level (between 0.4 and 4.0 μIU/mL) will indicate that the medicine is working.
Now, assume that a 45-year-old man was diagnosed with hypothyroidism and was prescribed levothyroxine as its treatment. The physician asked him to return after a month for a TSH test to see if the levels had dropped and whether the medication was working. Hence, the lab analyst will use CPT code 84443 to collect reimbursement for the test.
Applicable Modifiers for CPT Code 84443
Modifiers are two-digit medical codes that help provide supplemental information to the insurance payer regarding a clinical procedure or service. For example, you can use modifiers with the CPT and HCPCS codes to explain who performed the service and under what circumstances. A few modifiers that are commonly appended to CPT code 84443 include:
Modifier 33
Appending modifier 33 to a pathology CPT code explains that the service or lab test was preventive. So, you should append modifier 33 to CPT code 84443 when the TSH blood test is being performed as part of preventive screening, the insurance payer is a commercial one, and the routine TSH screening is covered by the payer.
Modifier 90
Modifier 90 explains that the blood test was performed at an outside laboratory, but another provider is billing for it. So, for example, if you are an in-network provider and do not have the facility and resources to perform a TSH test, you can send the blood sample to an outside lab and bill it under your name. In this case, however, you must append modifier 90 to CPT code 84443.
Modifier 91
Modifier 91 indicates repeat tests that are performed on the same day. So, if you repeated the TSH test on the same day to obtain subsequent results, modifier 91 can be appended to CPT code 84443 to explain this to the payer.
Modifier QW
Thyroid-stimulating hormone test, represented by CPT code 84443, is a Clinical Laboratory Improvement Amendments (CLIA)-waived lab test. It means that the FDA has designated this test as “having a low risk of erroneous results”. Therefore, it is exempt from the stringent CLIA regulatory requirements.
However, you must append modifier QW to CPT code 84443 to explain to the insurance payer that the TSH test was performed using the specific CLIA test kit from manufacturers identified and approved by the Centers for Medicare & Medicaid Services (CMS).
CPT Code 84443 – Billing & Reimbursement Guidelines
Can you guarantee fast and full reimbursements just by entering the correct CPT code and modifiers? The answer is NO. It takes a lot more than that to ensure your submitted claims are error-free and compliant with the payer’s billing policies. Let’s discuss some billing dos and don’ts that are specific to CPT code 84443.
Do Not Confuse CPT Code 84443 with 84439
CPT codes 84439 and 84443 are both used to describe blood tests that were performed to assess the patient’s thyroid function. However, these two codes and the blood tests they represent are very different.
CPT code 84439 denotes that the lab analyst took a blood sample from the patient’s arm vein to measure the level of free thyroxine (T4) in the bloodstream. In contrast, CPT code 84443 reports that the lab analyst performed a blood test to measure the level of thyroid-stimulating hormone (TSH) in the patient’s blood. As we have discussed above, both are different hormones produced and released by distinct glands.
Therefore, you should report CPT code 84443 only when TSH levels in the blood are measured.
Do Not Report CPT Code 84443 More Than Twice Per Year
In the case of a clinically stable Medicare beneficiary, you are not allowed to perform thyroid testing (covered by CPT code 84443) more than twice a year. However, the CMS will accept frequent testing if it is reasonable and medically necessary. For example, if the patient’s thyroid therapy was altered or if new symptoms or signs of thyroid disorders (hyperthyroidism and hypothyroidism) are noticeable.
Report CPT Code 84443 Only for Diagnosis or Treatment Follow-Up
You must understand that Medicare does not accept TSH testing (CPT code 84443) for preventive reasons. You can only perform the TSH blood test and report it with CPT code 84443 if the purpose was to diagnose a thyroid disorder and follow up on the patient’s health after diagnosis and treatment.
According to the CMS guidelines, thyroid testing may be necessary when:
- You have to differentiate between primary and secondary hypothyroidism.
- Diagnose or rule out hyperthyroidism or hypothyroidism.
- Monitor the levels of thyroid hormones (T3 and T4) in patients with goiter (enlarged thyroid gland, bulge on the neck), thyroid nodules, or thyroid cancer.
- Assess the effectiveness of drug therapy in patients with hypothyroidism or hyperthyroidism.
Pair CPT Code 84443 with the Appropriate Diagnosis Codes
Medicare accepts the medical necessity of a TSH blood test (CPT code 84443) in patients with the following conditions:
- Malnutrition
- Hyperlipidemia
- Certain types of anemia
- Psychosis and non-psychotic personality disorders
- Unexplained depression
- Ophthalmologic disorders
- Various cardiac arrhythmias
- Disorders of menstruation
- Skin conditions
- Myalgias
- Alterations in consciousness
- Malaise
- Hypothermia
- Symptoms of the nervous and musculoskeletal system
Therefore, you should use the most appropriate ICD-10 diagnosis codes to justify the need for a TSH test and prevent its claim denial.
Besides the CPT code 84443-specific billing tips we mentioned above, be sure to follow each payer’s particular policies regarding the billing of laboratory tests and submit complete documentation to prove the test’s medical necessity.
Summary
Did the main points get buried under the heap of information? Relax! Let’s do a quick recap to jog your memory on CPT code 84443. We discussed that CPT code 84443 reports a laboratory test where the technician measures the level of thyroid-stimulating hormone in the patient’s blood and assesses the thyroid function.
The test is necessary to diagnose thyroid disorders like hypothyroidism and hyperthyroidism, evaluate the effectiveness of drug therapies, and monitor thyroid function during pregnancy. You may append modifiers 33, 90, 91, and QW to CPT 84443 for coding specificity.
Hopefully, with our billing tips, you will be able to file clean and compliant claims for CPT code 84443. However, if you encounter hurdles along the way, consider our pathology billing services and notice the difference.
