Examqo › Examqo library › Neurology › Neuromuscular disease · IMLE
Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP)
CIDP is the "chronic sister" of Guillain-Barré syndrome: symmetric proximal and distal weakness with absent reflexes progressing for more than 8 weeks, and unlike GBS it also responds to steroids, alongside IVIG and plasma exchange.
Why it matters in the exam
Questions present a patient with weakness of arms and legs, including proximal muscles, sensory loss and absent reflexes worsening over months, or a "GBS" patient who keeps worsening or relapses again and again. They test the 8-week timeline, the electrical study showing demyelination, the raised CSF protein, and the fact that steroids work here. An important part is spotting mimics: anti-MAG neuropathy with an IgM paraprotein, POEMS syndrome, and multifocal motor neuropathy (MMN), in which steroids may worsen the disease. A classic distractor is giving steroids for MMN or thinking steroids fail in CIDP as they do in GBS. In diabetes a distal sensory neuropathy is very common and is not CIDP; suspicion rises only with proximal weakness, completely absent reflexes and faster worsening than expected.
Key points
- CIDP: a symmetric proximal and distal neuropathy with absent reflexes progressing over 8 weeks.
- Diagnosis by an electrical study showing demyelination and raised CSF protein.
- IVIG, steroids and plasma exchange are effective, unlike GBS where steroids are not.
- MMN: asymmetric motor weakness in the hands with conduction block — IVIG, not steroids.
- An IgM paraprotein with MAG or POEMS are mimics to exclude.
Summary table
| Condition | Features | Treatment |
|---|---|---|
| Typical CIDP | Symmetric proximal and distal weakness, sensory loss, absent reflexes, progression over 8 weeks | IVIG, steroids or plasma exchange — all effective; subcutaneous IVIG for maintenance |
| GBS versus CIDP | GBS — peak within 4 weeks; between 4 and 8 weeks — subacute; repeated relapses (3 or more) or worsening after 8 weeks — CIDP | In GBS steroids are not effective |
| Multifocal motor neuropathy (MMN) | Asymmetric weakness of the hands only, no sensory loss, conduction block, GM1 antibodies | IVIG; steroids may worsen it |
| Anti-MAG and POEMS | Distal sensory loss with an IgM paraprotein (MAG); lambda paraprotein, high VEGF and bone lesions (POEMS) | Do not respond like CIDP; treat the haematological disease |
| Nodal antibodies | Antibodies against NF155 or CNTN1, tremor and ataxia, poor response to IVIG | Rituximab |
A free exam question
באיזה מהמצבים הבאים נצפה תהליך של Wallerian degeneration ? (the question as examined, in Hebrew)
- א. Anti-Hu sensory neuronopathy
- ב. Motor neuron disease
- ג. Multifocal motor neuropathy
- ד. Section of dorsal spinal root
In the full version for subscribers
- A simple algorithm
- Memory aid
- Exam traps
- 5 review cards
- Enough for IMLE
The full version is open to subscribers of: Neurology, Medical licensing exam (IMLE), Internal medicine.
Subscriber? Read the full topic Plans and prices 25 free questions
Sources
- EAN/PNS Guideline on Diagnosis and Treatment of Chronic Inflammatory Demyelinating Polyradiculoneuropathy, 2021 — Clinical and electrodiagnostic criteria, treatment
- EFNS/PNS Guideline on Multifocal Motor Neuropathy, 2010 — Diagnosis and IVIG treatment
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.