# Situation: A 41-year-old man is admitted to the medical ward with weakness that began in both feet 3 days ago and has now reached his thighs. He had diarrhea 2 weeks earlier. His knee and ankle reflexes are absent, and he reports tingling in both feet. Guillain-Barré syndrome (GBS) is suspected. On the 10th day of his illness, a lumbar puncture is done. Which cerebrospinal fluid (CSF) result supports the diagnosis of GBS?

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> subject: Nursing Practice III — Care of Clients with Problems in Surgery, Oxygenation, Fluid and Electrolytes, Infectious, Inflammatory and Immunologic Response, Cellular Aberrations

## 문제

Situation: A 41-year-old man is admitted to the medical ward with weakness that began in both feet 3 days ago and has now reached his thighs. He had diarrhea 2 weeks earlier. His knee and ankle reflexes are absent, and he reports tingling in both feet. Guillain-Barré syndrome (GBS) is suspected.

On the 10th day of his illness, a lumbar puncture is done. Which cerebrospinal fluid (CSF) result supports the diagnosis of GBS?

## 보기

1. High protein with a normal white cell count **✔ 정답**
2. High white cell count with a normal protein
3. Low glucose with a high neutrophil count
4. Oligoclonal bands with a normal cell count

**정답: 1**

## 해설

GBS shows albuminocytologic dissociation: a high CSF protein with a normal cell count. It may be absent in the first week, which is why the test is timed later. Oligoclonal bands point to multiple sclerosis, and low glucose with many neutrophils points to bacterial meningitis.

## 심화 해설

Core CSF finding in GBS

The cerebrospinal fluid pattern that supports Guillain–Barré syndrome is albuminocytologic dissociation: the protein level rises while the white cell count stays normal. In this patient, the lumbar puncture was deliberately performed on day 10 because this dissociation is often absent during the first week of illness. A large international cohort of 1,231 patients found this pattern in 70% of cases when protein was defined as above 0.45 g/L with fewer than 50 cells/μL [4]. A meta-analysis similarly confirms that the diagnostic yield depends on both the timing of the tap and the protein threshold used [1].

The elevated protein reflects inflammation and disruption of the blood–nerve barrier at the spinal nerve roots, where the immune attack in GBS is concentrated. Because the pathology is centered on peripheral nerve roots rather than the meninges or brain parenchyma, inflammatory cells do not pour into the CSF in large numbers. This explains the combination of high protein with a normal cell count [2].

| CSF pattern | Typical condition | Why it differs from GBS |
| --- | --- | --- |
| High protein, normal cells | GBS (albuminocytologic dissociation) | Root-level inflammation raises protein without pleocytosis |
| High white cells, normal protein | Viral meningitis, early infection | Meningeal inflammation draws leukocytes into CSF |
| Low glucose, high neutrophils | Bacterial meningitis | Bacteria consume glucose and provoke a purulent response |
| Oligoclonal bands, normal cells | Multiple sclerosis | Intrathecal antibody synthesis within the CNS |

Key point! A normal CSF cell count is essential for the diagnosis. In GBS, a cell count above 50 cells/μL should prompt reconsideration of the diagnosis, such as infection, malignancy, or another inflammatory neuropathy [3][4]. Watch out! Protein elevation may be missed if the lumbar puncture is performed too early. Repeating the tap after the first week increases the likelihood of detecting albuminocytologic dissociation [1][4].

The age of the patient also matters. Because normal CSF protein rises with age, using an age-adjusted upper reference limit can identify albuminocytologic dissociation in older patients who would otherwise fall below the conventional 0.45 g/L cutoff [3]. In a 41-year-old man, the conventional threshold is generally appropriate, but the principle of timing remains the dominant clinical consideration.References (research sources)

- [1]Time- and threshold-dependent cerebrospinal fluid protein elevation and albuminocytologic dissociation in Guillain-Barré syndrome: a systematic review and meta-analysis.Meta-analysis/systematic reviewLu X, Dai H, Zhao L, Huang W. (2026) · DOI: 10.1007/s00415-026-14024-4

- [2]Cerebrospinal fluid findings in Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathies.Research articleIlles Z, Blaabjerg M (2017) · DOI: 10.1016/B978-0-12-804279-3.00009-5

- [3]Albuminocytologic Dissociation and the Impact of Age-Adjusted Cerebrospinal Fluid Protein Levels in Guillain-Barré Syndrome.Research articleThatikonda N, Lerint A, Takle C, Fang X, Patel C (2025) · DOI: 10.3390/neurolint17020018

- [4]CSF Findings in Relation to Clinical Characteristics, Subtype, and Disease Course in Patients With Guillain-Barré Syndrome.Research articleAl-Hakem H, Doets AY, Stino AM, Zivkovic SA, Andersen H, Willison HJ (2023) · DOI: 10.1212/WNL.0000000000207282

## 임상 시나리오

GBS CSF InterpretationAlbuminocytologic dissociation on day 10
In Guillain-Barré syndrome, the key CSF finding is albuminocytologic dissociation: high protein with a normal white cell count. This reflects inflammation at the spinal nerve roots, not meningeal infection.

Timing matters. The dissociation is often absent in the first week, so a lumbar puncture is more useful around day 10 of illness. A large cohort found this pattern in about 70% of cases using a protein threshold above 0.45 g/L and fewer than 50 cells/μL.

CautionDo not mistake other patterns for GBS: high white cells with normal protein suggests viral meningitis, low glucose with high neutrophils suggests bacterial meningitis, and oligoclonal bands suggest multiple sclerosis.

## 핵심 개념

- **albuminocytologic dissociation** — Elevated CSF protein with a normal white cell count, the hallmark CSF finding in Guillain-Barré syndrome
- **Guillain-Barré syndrome** — Acute immune-mediated polyradiculoneuropathy often presenting with ascending weakness and areflexia after infection
- **lumbar puncture** — Procedure to sample cerebrospinal fluid; in GBS it is most informative after the first week of illness
- **pleocytosis** — Abnormally high white cell count in CSF, typically absent in GBS
- **oligoclonal bands** — CSF immunoglobulin bands that suggest intrathecal antibody synthesis, classically seen in multiple sclerosis

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