How is CIDP diagnosed?

An accurate CIDP diagnosis is dependent on tests like an EMG, MRI, or nerve conduction test, to name a few

Doctor sharing diagnosis with patient

It can be a challenge to diagnose CIDP

CIDP symptoms resemble those of other nervous system disorders. Because of the similarities with symptoms of other disorders, it can take several months to obtain an accurate diagnosis of CIDP. However, there are some tests and tools doctors use to help assess patients.1

In most cases, a diagnosis will come from a neurologist or a neuromuscular specialist that you will have been referred to by another doctor.

Doctor sharing diagnosis with patient

It is important to catch CIDP early

If CIDP is caught early enough, it can be treated, depending on your specific case. The sooner you are evaluated by a neuromuscular specialist or neurologist who is familiar with CIDP, the sooner you can begin treatment.

Tools and tests used to assess and diagnose CIDP

Neurologist Evaluation

Your doctor will typically review your medical history and ask you a variety of questions about your symptoms, including when they started, where you feel them, and how long you’ve had them. Be prepared to discuss your symptoms with your doctor. Your doctor will then perform a physical exam.

Physical Exam

During your initial appointment, your doctor will perform a physical exam to evaluate your symptoms and may also collect blood samples for laboratory testing. The physical exam will evaluate things such as your strength, sensations, reflexes, gait, and coordination. This will help them get familiar with your overall state of health and help them to rule out or identify certain conditions.2

Electromyography (EMG)

This procedure evaluates nerve and muscle. Nerve conduction studies (NCS) involve applying electricity to nerve and recording from nerve or muscle. Needle EMG involves recording the muscle’s electrical activity. The test can help reveal the type and degree of nerve and muscle damage.3

Lumbar Puncture or Spinal Tap

This is an optional medical procedure where a needle is inserted into the lower part of the spine to obtain a small sample of the liquid surrounding your spinal cord. This procedure tests for conditions affecting the brain, spinal cord, or other parts of the nervous system.4

Magnetic Resonance Imaging (MRI)

This is an optional test that uses a powerful magnetic field to take images, such as images of the spinal cord and nerve bundles. An MRI can help in the diagnosis of CIDP by detecting damage to the nerves.5

Nerve Biopsy

This is an optional and rarely performed procedure where a sample of a nerve is taken from your body and looked at under a microscope. A nerve biopsy can be done to either confirm CIDP or rule out other conditions.1,6

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  1. Evers E, Hughes R. CIDP and the Chronic Variants. Heckington, Sleaford Lincolnshire, UK: Guillain-Barré & Associated Inflammatory Neuropathies (GAIN); 2017.
  2. Koski CL. CIDP: Chronic Inflammatory Demyelinating Polyneuropathy. Narberth, PA: GBS/CIDP Foundation International; 2012.
  3. Electromyography (EMG). Mayo Clinic website. Accessed November 18, 2022.
  4. Lumbar puncture. NHS Choices website. Accessed November 18, 2022.
  5. Magnetic Resonance Imaging (MRI). WebMD website. Accessed November 18, 2022.
  6. Nerve biopsy: purpose, procedure, and risks. Healthline website. Accessed November 18, 2022.