Can I Sue an Illinois Doctor for a Misdiagnosis?

 Posted on July 07, 2026 in Medical Malpractice

When you visit an Illinois doctor or hospital, you expect your symptoms to be evaluated correctly. However, sometimes medical professionals fail to accurately diagnose medical conditions, something that can result in serious consequences for patients.

If you are a victim of misdiagnosis in Illinois, it may be possible to sue the doctor or hospital responsible and receive compensation for your injuries. A skilled Rockford, IL medical misdiagnosis lawyer can provide you with guidance. At Mannarino & Brasfield, A Division of Schwartz Jambois, we have handled many complex cases, having secured verdicts and settlements worth millions through clear arguments and detailed investigations.

What Are the Consequences of Medical Misdiagnosis?

Medical misdiagnosis can be very serious, and victims of misdiagnosis often suffer needlessly due to their doctor or medical professional’s incorrect evaluation. There are many consequences that may result from a medical misdiagnosis, including:

• Medical conditions that worsen without proper treatment, causing further illness

• Incorrect medications received that lead to further medical issues

• Extended hospital stays and additional medical bills

• Lost wages or employment due to medical conditions

• Wrongful death, in the case that a serious medical condition does not receive treatment

• Permanent disability

• Pain, suffering, and emotional trauma

How Do I Pursue a Medical Misdiagnosis Claim in 2026?

In Illinois, medical misdiagnosis claims are a type of medical malpractice. The law states that you have two years to file a medical malpractice lawsuit unless you find an injury later on (735 ILCS 5/13-212). If the victim is a minor, different rules may apply. Because these timelines can be difficult to calculate on your own, speaking with an attorney as early as possible gives you the best chance of protecting your rights.

For your medical misdiagnosis claim to succeed, you will need to prove that the medical professional diagnosing you did one or more of the following:

• Failed to correctly interpret your symptoms

• Ignored or downplayed symptoms you reported

• Acted negligently when ordering or administering tests

• Failed to contact or consult the appropriate specialists

• Misread or improperly handled test results

You need to show that these actions resulted in a misdiagnosis. In turn, that misdiagnosis must have caused real harm. An experienced attorney can help you navigate the collection of documents and pursuit of compensation with such a claim.

Who Can Be Held Liable for a Medical Misdiagnosis?

More than one party can be responsible for a misdiagnosis. The doctor who examined you is often the starting point. A physician can be liable for failing to order the right tests, ignoring symptoms, or reaching a conclusion too quickly. Specialists who reviewed test results can also share responsibility if they misread findings or failed to communicate concerns clearly.

Hospitals and medical groups can face liability as well. If a facility had poor staffing, inadequate training, or faulty equipment that contributed to the error, it may bear some of the blame. Laboratories that processed or reported test results incorrectly can also be involved. Illinois law requires showing that the care provided fell below what a reasonably competent medical professional would have done under the same circumstances. 

What Kind of Evidence Do You Need for a Medical Malpractice Claim?

Medical malpractice claims depend heavily on documentation. Your medical records are the foundation. They can show what the doctor knew, what was done, and where the process broke down.

An expert opinion is also required under Illinois law. A qualified medical expert must review your case and confirm that the care you received fell below the accepted standard. Without that, the claim cannot move forward. Your attorney can help identify the right expert for your specific situation.

Other useful evidence can include billing records and correspondence with your care team. Records showing how your condition progressed after the misdiagnosis can also help. If your health declined because of the error, you’ll need to show the timeline supports your claim. The stronger and more complete the record, the better positioned your claim will be.

What Are the Most Commonly Misdiagnosed Conditions That Lead to Harm?

Some conditions are misdiagnosed more often than others. Cancer is one of the most serious. Lung cancer, breast cancer, and colorectal cancer are frequently missed or mistaken for less urgent conditions. A delayed cancer diagnosis can mean the difference between catching it early and running out of treatment options.

Heart attacks are also commonly misdiagnosed, especially in women. Their symptoms often look different from what doctors are trained to expect. Strokes can be misdiagnosed as well. In all of these cases, a delayed or wrong diagnosis can cause permanent harm or death.

Mental health conditions, appendicitis, and autoimmune diseases are also misdiagnosed at troubling rates. A wrong answer from a doctor can cost a patient weeks or months of proper treatment.

How Are Medical Misdiagnosis Claims Handled in Illinois?

Most medical malpractice claims in Illinois are resolved through settlement rather than trial. Settlement allows both sides to avoid the cost and uncertainty of litigation. However, a fair settlement requires strong evidence and preparation. Insurance companies representing hospitals and physicians are experienced at defending these claims. They will look for ways to minimize what they pay.

If a fair settlement cannot be reached, the case may go to trial. A judge or jury will hear the evidence and review expert testimony. They will then decide whether malpractice occurred and what compensation is owed. Illinois also requires that plaintiffs file an affidavit of merit at the start of a case. This document must be signed by a qualified medical professional confirming that the claim has a reasonable basis.

Contact a Rockford, IL Medical Misdiagnosis Attorney

Medical misdiagnosis cases can be complex, and proving that a doctor or medical professional caused your medical misdiagnosis is difficult. You will need the assistance of a seasoned Winnebago County, IL medical malpractice lawyer to help advocate for you and the compensation you deserve.

At Mannarino & Brasfield, A Division of Schwartz Jambois, our attorneys have a successful record dealing with medical misdiagnosis cases and winning significant settlements for our clients. We know how insurance companies operate, and we can help you get the evidence you need to build your case. Call 815-215-7561 for a free consultation about your legal options.