Master Vignesh, a 7-year-old boy, 2nd order child of non-consanguineous marriage from Coimbatore, Tamil Nadu presented with complaints of rapidly progressive weakness of both lower limbs progressing to both upper limbs over 4 days, inability to walk, and difficulty in closing both eyes noticed 2 days prior to presentation.

HOPI

• Antecedent Illness:
  • The child had an episode of acute febrile watery diarrhea with abdominal cramps approximately 2 weeks prior to the onset of weakness (characteristic antecedent Campylobacter jejuni enteritis), which resolved completely in 3 days with oral rehydration therapy.
• Onset & Ascending Progression of Weakness:
  • 4 days ago, the child complained of pain and tingling sensation in both feet and calves, followed by difficulty getting up from a sitting position and unsteady gait.
  • By Day 2 of illness, weakness progressed rapidly; the child became completely unable to walk, stand, or climb stairs, and was confined to bed.
  • By Day 3 of illness, weakness ascended to involve both upper limbs; the child had difficulty lifting his arms to feed himself, raising hands above the shoulder level, and holding a pencil or cup.
• Cranial Nerve Symptoms (Facial Diplegia):
  • 2 days ago, the mother noticed that the child was unable to close both eyes completely while sleeping (lagophthalmos) and had difficulty blowing his cheeks, drinking through a straw, or holding water in his mouth.
  • Mild slurring of speech was observed; no frank choking or nasal regurgitation of fluids.
• Respiratory & Autonomic Symptoms:
  • Child has mild breathlessness on talking; his single breath count (SBC) has decreased from normal ($>25$) to 12.
  • Mother noted intermittent excessive sweating of palms and flushing of face.

Pertinent Negatives in HOPI:

• No history of fever at the onset of weakness (rules out acute poliomyelitis and acute transverse myelitis).
• No history of back trauma, falls, or localized vertebral spine tenderness (rules out spinal cord compression/hematoma).
• No history of a definitive sensory level on the trunk (rules out acute transverse myelitis).
• No history of acute urinary retention requiring catheterization (rules out transverse myelitis; bladder is typically preserved or only transiently affected in GBS).
• No history of dog bite (rules out paralytic rabies).
• No history of canned food or honey ingestion (rules out botulism).
• No history of tick bites or intramuscular gluteal injections (rules out tick paralysis and traumatic sciatic neuritis).
• No history of diurnal fluctuation of weakness or fatiguability (rules out Myasthenia Gravis).
• No history of similar episodic weakness in the past (rules out hypokalemic periodic paralysis).

Past History

• No history of previous episodes of acute flaccid paralysis or chronic neurological illnesses.
• No history of recent vaccinations (rabies, OPV) in the preceding 6 weeks.
• No history of drug allergies or surgical procedures.

Family history

• 2nd-order male child born to non-consanguineously married parents.
• Elder sister (10 years old) is healthy and asymptomatic.
• No family history of hereditary motor sensory neuropathies (Charcot-Marie-Tooth) or periodic paralyses.

Immunization history

• Completely immunized for age per National Immunization Schedule (BCG, OPV 0-3, Pentavalent 1-3, fIPV, MR 1-2, DPT booster).
• BCG scar is present on left deltoid.

Dietary history

• Regular family diet; independent feeder prior to illness; currently fed semi-solids in bed due to arm weakness.

The expected calories and proteins should be calculated from the ideal body weight, not from current weight.

Socioeconomic and KAP

• Family resides in a pucca house with sanitary latrine and piped drinking water in Coimbatore.
• Father is an industrial supervisor; Mother is a graduate homemaker.
• Socioeconomic Status: Upper-middle class (Modified Kuppuswamy Score: 19).
• Parents brought the child promptly recognizing the rapid ascending nature of the paralysis.

Summary of History

General head to toe examination

Pre-Examination Child Behavioral State

• Child State: Alert, anxious, cooperative, breathing comfortably at rest (Prechtl State 3: quiet wakefulness).
• Glasgow Coma Scale (GCS): E4 V5 M6 = 15/15.

Vitals & Autonomic Monitoring

• Pulse Rate: 108 bpm (resting sinus tachycardia, reflecting mild autonomic dysfunction), regular.
• Blood Pressure: 116/78 mmHg (supine) $\rightarrow$ 102/66 mmHg (seated) — mild orthostatic drop without syncope.
• Respiratory Rate: 24/min, shallow abdominothoracic pattern.
• Single Breath Count (SBC): 12 (Normal $\ge 25$; $<15$ signifies significant respiratory muscle weakness).
• Neck Flexor Power: Grade 3/5 (unable to lift head against resistance, an important marker of impending diaphragmatic weakness).

Anthropometry

Head-to-Toe Markers

• Facies: Expressionless facies with bilateral incomplete eye closure (lagophthalmos) and sagging mouth angles.
• Spine: Normal alignment; no vertebral tenderness or paraspinal muscle spasm.
• Extremities: No skin rashes, tick marks, trauma scars, or calf pseudo-hypertrophy.

Systemic Examination

CNS Examination

1. Cranial Nerves

• CN VII (Facial Nerve): Bilateral Lower Motor Neuron (LMN) Facial Palsy (Bifacial Weakness):
  • Inability to close both eyes tightly (sclera exposed / Bell's phenomenon visible bilaterally).
  • Flattening of forehead wrinkles bilaterally; inability to puff cheeks or whistle; droop of both mouth angles.
• CN IX, X (Bulbar Nerves): Gag reflex present; uvula central; no pooling of secretions or nasal regurgitation.
• CN III, IV, VI, XI, XII: Normal extraocular movements, normal sternocleidomastoid power, tongue protrudes in midline without wasting or fasciculations.

2. Motor System (Granular Power Charting)

3. Sensory & Cerebellar System

• Sensory Examination: Subjective complaints of stocking-and-glove paresthesias; objective pinprick, light touch, vibration, and joint position sensations are intact without a spinal sensory level.
• Cerebellar System: No nystagmus, intention tremor, or dysmetria.

other systems

• Respiratory System: Bilateral chest expansion slightly decreased (2.0 cm); vesicular breath sounds; no adventitious sounds.
• Cardiovascular System: Resting sinus tachycardia (108 bpm); normal heart sounds; no murmurs.
• Abdomen: Soft, non-tender; no urinary bladder distension; bowel sounds present.

Summary

Differential Diagnosis

Investigation Protocol & Diagnostic Workup

flowchart TD
    A["Suspected Guillain-Barré Syndrome"] --> B["1. Urgent Bedside Evaluation: Vital Capacity, Single Breath Count, ECG, Serum Electrolytes"]
    B --> C["2. Mandatory Stool Surveillance: 2 Stool Samples 24h apart for Poliovirus Isolation"]
    A --> D["3. Cerebrospinal Fluid (CSF) Analysis (after Day 7 of illness)"]
    D --> E["Cytoalbuminologic Dissociation: Elevated Protein (>100–300 mg/dL) with Normal Cells (<5–10 lymphocytes)"]
    A --> F["4. Nerve Conduction Velocity (NCV) Studies"]
    F -->|Demyelinating: Prolonged F-latencies, Conduction Block, Slow NCV| G["AIDP Variant Confirmed"]
    F -->|Axonal: Reduced CMAP amplitudes with normal velocities| H["AMAN / AMSAN Variant Confirmed"]

1. Bedside & Triage Investigations

• Single Breath Count (SBC) & Forced Vital Capacity (FVC):
  • SBC $<15$ or FVC $<20\text{ mL/kg}$ indicates severe diaphragmatic weakness requiring ICU admission and preparation for elective intubation.
• Serum Electrolytes (Na⁺, K⁺): Normal potassium ($4.2\text{ mEq/L}$) immediately excludes hypokalemic periodic paralysis.
• Continuous 12-Lead ECG Monitoring: Screen for dysautonomia (sinus tachycardia, bradyarrhythmias, heart blocks, fluctuating blood pressure).

2. Mandatory Poliovirus Surveillance Protocol

• Stool Samples for AFP Surveillance:
  • Two adequate stool samples collected at least 24 hours apart within 14 days of paralysis onset must be sent in reverse cold chain ($<4^\circ\text{C}$) to an accredited WHO laboratory for viral culture.

3. Cerebrospinal Fluid (CSF) Analysis

• Classic Cytoalbuminologic Dissociation:
  • Markedly elevated CSF Protein ($100\text{ to }400+\text{ mg/dL}$) with a normal CSF white cell count ($<5\text{ to }10\text{ cells/}\mu\text{L}$, all lymphocytes).
  • Timing Pearl: CSF protein may be normal during the first 3–7 days of illness; the peak protein elevation occurs in the 2nd to 3rd week.

4. Electrophysiological Nerve Conduction Studies (NCV / EMG)

• AIDP (Demyelinating Pattern): Prolonged distal motor latencies, markedly reduced conduction velocities ($<70\%$ of normal), conduction blocks, temporal dispersion, and prolonged or absent F-waves (earliest sign of proximal radiculopathy).
• AMAN (Axonal Pattern): Markedly reduced distal Compound Muscle Action Potential (CMAP) amplitudes with preserved conduction velocities.

Management Plan

flowchart LR
    A["Comprehensive GBS Care"] --> B["1. Specific Immunotherapy (IVIG / Plasmapheresis)"]
    A --> C["2. ICU Monitoring & Airway Protection"]
    A --> D["3. Dysautonomia & Pain Control"]
    A --> E["4. Physical Therapy & DVT Prophylaxis"]

1. Specific Immunotherapy (Gold Standard)

• Indications: Hughes Disability Grade $\ge 3$ (unable to walk $10\text{ meters}$ unaided), rapidly ascending weakness, bulbar palsy, or declining vital capacity.
• Option A (Intravenous Immunoglobulin - IVIG) (Preferred in Children):
  • Total Dose: $2.0\text{ g/kg}$ IV infusion:
    • Regimen: $0.4\text{ g/kg/day}$ infused over 4–6 hours daily for 5 consecutive days, OR $1.0\text{ g/kg/day}$ for 2 consecutive days.
    • Pre-medicate with IV paracetamol and chlorpheniramine; monitor for anaphylactoid reactions.
• Option B (Plasma Exchange / Plasmapheresis):
  • $200\text{–}250\text{ mL/kg}$ total exchange over 4–5 sessions every other day using 5% albumin as replacement fluid.
• Note: Corticosteroids are NOT effective in GBS and should not be administered.

2. Respiratory Monitoring & Intubation Criteria ("Rule of 20/30/40")

• Elective Intubation & Mechanical Ventilation Criteria:
  • Forced Vital Capacity $<20\text{ mL/kg}$ (or SBC $<10$).
  • Maximum Inspiratory Pressure (MIP) $<30\text{ cm H}_2\text{O}$.
  • Maximum Expiratory Pressure (MEP) $<40\text{ cm H}_2\text{O}$.
  • Inability to lift head off the bed (severe neck flexor weakness), severe bulbar palsy with aspiration risk, or paradoxical abdominal breathing.

3. Autonomic Instability & Supportive Care

• Cardiovascular Support: Short-acting beta-blockers (Esmolol) for severe hypertension/tachycardia; Atropine or temporary pacing for profound bradycardia; cautious isotonic fluid boluses for hypotension.
• Neuropathic Pain Management: Gabapentin ($10\text{–}30\text{ mg/kg/day}$) or Pregabalin for severe paraspinal and radicular limb aching.
• Nursing & Physical Therapy: Frequent 2-hourly turning, air-mattress, passive range-of-motion exercises, and Ankle-Foot Orthoses to prevent foot drop contractures.